[GO][Client] Multipart/form-data Request Support More Than One File (#10843)

* Instead of limiting a request to a single file when
performing an upload, use a slice of files so an
arbitrary number of files can be used in the form.

* Remove commented out line of code

* Update examples for multi-form file fix for multiple files

* Convert spaces to tabs for indentation

* Updated examples to have tabs instead of spaces

* Add an example of a multipart/form-data OA3 schema
that contains two files to be uploaded

modules/openapi-generator/src/main/resources/go/api.mustache

@@ -109,9 +109,7 @@ func (a *{{{classname}}}Service) {{nickname}}Execute(r {{#structPrefix}}{{&class
 	var (
 		localVarHTTPMethod   = _nethttp.Method{{httpMethod}}
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		{{#returnType}}
 		localVarReturnValue  {{{.}}}
 		{{/returnType}}
@@ -251,22 +249,28 @@ func (a *{{{classname}}}Service) {{nickname}}Execute(r {{#structPrefix}}{{&class
 {{/headerParams}}
 {{#formParams}}
 {{#isFile}}
-	localVarFormFileName = "{{baseName}}"
+	var {{paramName}}LocalVarFormFileName string
+	var {{paramName}}LocalVarFileName     string
+	var {{paramName}}LocalVarFileBytes    []byte
+
+	{{paramName}}LocalVarFormFileName = "{{baseName}}"
+
 {{#required}}
-	localVarFile := *r.{{paramName}}
+	{{paramName}}LocalVarFile := *r.{{paramName}}
 {{/required}}
 {{^required}}
-	var localVarFile {{dataType}}
+	var {{paramName}}LocalVarFile {{dataType}}
 	if r.{{paramName}} != nil {
-		localVarFile = *r.{{paramName}}
+		{{paramName}}LocalVarFile = *r.{{paramName}}
 	}
 {{/required}}
-	if localVarFile != nil {
+	if {{paramName}}LocalVarFile != nil {
-		fbs, _ := _ioutil.ReadAll(localVarFile)
+		fbs, _ := _ioutil.ReadAll({{paramName}}LocalVarFile)
-		localVarFileBytes = fbs
+		{{paramName}}LocalVarFileBytes = fbs
-		localVarFileName = localVarFile.Name()
+		{{paramName}}LocalVarFileName = {{paramName}}LocalVarFile.Name()
-		localVarFile.Close()
+		{{paramName}}LocalVarFile.Close()
 	}
+	formFiles = append(formFiles, formFile{fileBytes: {{paramName}}LocalVarFileBytes, fileName: {{paramName}}LocalVarFileName, formFileName: {{paramName}}LocalVarFormFileName})
 {{/isFile}}
 {{^isFile}}
 {{#required}}
@@ -330,7 +334,7 @@ func (a *{{{classname}}}Service) {{nickname}}Execute(r {{#structPrefix}}{{&class
 {{/isKeyInCookie}}
 {{/isApiKey}}
 {{/authMethods}}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return {{#returnType}}localVarReturnValue, {{/returnType}}nil, err
 	}

modules/openapi-generator/src/main/resources/go/client.mustache

@@ -196,6 +196,12 @@ func (c *APIClient) GetConfig() *Configuration {
 	return c.cfg
 }
 
+type formFile struct {
+		fileBytes []byte
+		fileName string
+		formFileName string
+}
+
 // prepareRequest build the request
 func (c *APIClient) prepareRequest(
 	ctx context.Context,
@@ -204,9 +210,7 @@ func (c *APIClient) prepareRequest(
 	headerParams map[string]string,
 	queryParams url.Values,
 	formParams url.Values,
-	formFileName string,
+	formFiles []formFile) (localVarRequest *http.Request, err error) {
-	fileName string,
-	fileBytes []byte) (localVarRequest *http.Request, err error) {
 
 	var body *bytes.Buffer
 
@@ -225,7 +229,7 @@ func (c *APIClient) prepareRequest(
 	}
 
 	// add form parameters and file if available.
-	if strings.HasPrefix(headerParams["Content-Type"], "multipart/form-data") && len(formParams) > 0 || (len(fileBytes) > 0 && fileName != "") {
+	if strings.HasPrefix(headerParams["Content-Type"], "multipart/form-data") && len(formParams) > 0 || (len(formFiles) > 0) {
 		if body != nil {
 			return nil, errors.New("Cannot specify postBody and multipart form at the same time.")
 		}
@@ -244,18 +248,19 @@ func (c *APIClient) prepareRequest(
 				}
 			}
 		}
-		if len(fileBytes) > 0 && fileName != "" {
+		for _, formFile := range formFiles {
+			if len(formFile.fileBytes) > 0 && formFile.fileName != "" {
 				w.Boundary()
-			//_, fileNm := filepath.Split(fileName)
+				part, err := w.CreateFormFile(formFile.formFileName, filepath.Base(formFile.fileName))
-			part, err := w.CreateFormFile(formFileName, filepath.Base(fileName))
 				if err != nil {
 						return nil, err
 				}
-			_, err = part.Write(fileBytes)
+				_, err = part.Write(formFile.fileBytes)
 				if err != nil {
 						return nil, err
 				}
 			}
+		}
 
 		// Set the Boundary in the Content-Type
 		headerParams["Content-Type"] = w.FormDataContentType()

samples/client/petstore/go/go-petstore/api_another_fake.go

@@ -80,9 +80,7 @@ func (a *AnotherFakeApiService) Call123TestSpecialTagsExecute(r ApiCall123TestSp
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPatch
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  Client
 	)
 
@@ -119,7 +117,7 @@ func (a *AnotherFakeApiService) Call123TestSpecialTagsExecute(r ApiCall123TestSp
 	}
 	// body params
 	localVarPostBody = r.body
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}

samples/client/petstore/go/go-petstore/api_fake.go

@@ -252,9 +252,7 @@ func (a *FakeApiService) CreateXmlItemExecute(r ApiCreateXmlItemRequest) (*_neth
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPost
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "FakeApiService.CreateXmlItem")
@@ -290,7 +288,7 @@ func (a *FakeApiService) CreateXmlItemExecute(r ApiCreateXmlItemRequest) (*_neth
 	}
 	// body params
 	localVarPostBody = r.xmlItem
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}
@@ -355,9 +353,7 @@ func (a *FakeApiService) FakeOuterBooleanSerializeExecute(r ApiFakeOuterBooleanS
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPost
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  bool
 	)
 
@@ -391,7 +387,7 @@ func (a *FakeApiService) FakeOuterBooleanSerializeExecute(r ApiFakeOuterBooleanS
 	}
 	// body params
 	localVarPostBody = r.body
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}
@@ -465,9 +461,7 @@ func (a *FakeApiService) FakeOuterCompositeSerializeExecute(r ApiFakeOuterCompos
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPost
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  OuterComposite
 	)
 
@@ -501,7 +495,7 @@ func (a *FakeApiService) FakeOuterCompositeSerializeExecute(r ApiFakeOuterCompos
 	}
 	// body params
 	localVarPostBody = r.body
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}
@@ -575,9 +569,7 @@ func (a *FakeApiService) FakeOuterNumberSerializeExecute(r ApiFakeOuterNumberSer
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPost
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  float32
 	)
 
@@ -611,7 +603,7 @@ func (a *FakeApiService) FakeOuterNumberSerializeExecute(r ApiFakeOuterNumberSer
 	}
 	// body params
 	localVarPostBody = r.body
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}
@@ -685,9 +677,7 @@ func (a *FakeApiService) FakeOuterStringSerializeExecute(r ApiFakeOuterStringSer
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPost
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  string
 	)
 
@@ -721,7 +711,7 @@ func (a *FakeApiService) FakeOuterStringSerializeExecute(r ApiFakeOuterStringSer
 	}
 	// body params
 	localVarPostBody = r.body
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}
@@ -793,9 +783,7 @@ func (a *FakeApiService) TestBodyWithFileSchemaExecute(r ApiTestBodyWithFileSche
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPut
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "FakeApiService.TestBodyWithFileSchema")
@@ -831,7 +819,7 @@ func (a *FakeApiService) TestBodyWithFileSchemaExecute(r ApiTestBodyWithFileSche
 	}
 	// body params
 	localVarPostBody = r.body
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}
@@ -897,9 +885,7 @@ func (a *FakeApiService) TestBodyWithQueryParamsExecute(r ApiTestBodyWithQueryPa
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPut
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "FakeApiService.TestBodyWithQueryParams")
@@ -939,7 +925,7 @@ func (a *FakeApiService) TestBodyWithQueryParamsExecute(r ApiTestBodyWithQueryPa
 	}
 	// body params
 	localVarPostBody = r.body
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}
@@ -1004,9 +990,7 @@ func (a *FakeApiService) TestClientModelExecute(r ApiTestClientModelRequest) (Cl
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPatch
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  Client
 	)
 
@@ -1043,7 +1027,7 @@ func (a *FakeApiService) TestClientModelExecute(r ApiTestClientModelRequest) (Cl
 	}
 	// body params
 	localVarPostBody = r.body
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}
@@ -1197,9 +1181,7 @@ func (a *FakeApiService) TestEndpointParametersExecute(r ApiTestEndpointParamete
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPost
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "FakeApiService.TestEndpointParameters")
@@ -1273,17 +1255,23 @@ func (a *FakeApiService) TestEndpointParametersExecute(r ApiTestEndpointParamete
 	}
 	localVarFormParams.Add("pattern_without_delimiter", parameterToString(*r.patternWithoutDelimiter, ""))
 	localVarFormParams.Add("byte", parameterToString(*r.byte_, ""))
-	localVarFormFileName = "binary"
+	var binaryLocalVarFormFileName string
-	var localVarFile *os.File
+	var binaryLocalVarFileName     string
+	var binaryLocalVarFileBytes    []byte
+
+	binaryLocalVarFormFileName = "binary"
+
+	var binaryLocalVarFile *os.File
 	if r.binary != nil {
-		localVarFile = *r.binary
+		binaryLocalVarFile = *r.binary
 	}
-	if localVarFile != nil {
+	if binaryLocalVarFile != nil {
-		fbs, _ := _ioutil.ReadAll(localVarFile)
+		fbs, _ := _ioutil.ReadAll(binaryLocalVarFile)
-		localVarFileBytes = fbs
+		binaryLocalVarFileBytes = fbs
-		localVarFileName = localVarFile.Name()
+		binaryLocalVarFileName = binaryLocalVarFile.Name()
-		localVarFile.Close()
+		binaryLocalVarFile.Close()
 	}
+	formFiles = append(formFiles, formFile{fileBytes: binaryLocalVarFileBytes, fileName: binaryLocalVarFileName, formFileName: binaryLocalVarFormFileName})
 	if r.date != nil {
 		localVarFormParams.Add("date", parameterToString(*r.date, ""))
 	}
@@ -1296,7 +1284,7 @@ func (a *FakeApiService) TestEndpointParametersExecute(r ApiTestEndpointParamete
 	if r.callback != nil {
 		localVarFormParams.Add("callback", parameterToString(*r.callback, ""))
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}
@@ -1402,9 +1390,7 @@ func (a *FakeApiService) TestEnumParametersExecute(r ApiTestEnumParametersReques
 	var (
 		localVarHTTPMethod   = _nethttp.MethodGet
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "FakeApiService.TestEnumParameters")
@@ -1459,7 +1445,7 @@ func (a *FakeApiService) TestEnumParametersExecute(r ApiTestEnumParametersReques
 	if r.enumFormString != nil {
 		localVarFormParams.Add("enum_form_string", parameterToString(*r.enumFormString, ""))
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}
@@ -1553,9 +1539,7 @@ func (a *FakeApiService) TestGroupParametersExecute(r ApiTestGroupParametersRequ
 	var (
 		localVarHTTPMethod   = _nethttp.MethodDelete
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "FakeApiService.TestGroupParameters")
@@ -1607,7 +1591,7 @@ func (a *FakeApiService) TestGroupParametersExecute(r ApiTestGroupParametersRequ
 	if r.booleanGroup != nil {
 		localVarHeaderParams["boolean_group"] = parameterToString(*r.booleanGroup, "")
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}
@@ -1669,9 +1653,7 @@ func (a *FakeApiService) TestInlineAdditionalPropertiesExecute(r ApiTestInlineAd
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPost
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "FakeApiService.TestInlineAdditionalProperties")
@@ -1707,7 +1689,7 @@ func (a *FakeApiService) TestInlineAdditionalPropertiesExecute(r ApiTestInlineAd
 	}
 	// body params
 	localVarPostBody = r.param
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}
@@ -1775,9 +1757,7 @@ func (a *FakeApiService) TestJsonFormDataExecute(r ApiTestJsonFormDataRequest) (
 	var (
 		localVarHTTPMethod   = _nethttp.MethodGet
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "FakeApiService.TestJsonFormData")
@@ -1816,7 +1796,7 @@ func (a *FakeApiService) TestJsonFormDataExecute(r ApiTestJsonFormDataRequest) (
 	}
 	localVarFormParams.Add("param", parameterToString(*r.param, ""))
 	localVarFormParams.Add("param2", parameterToString(*r.param2, ""))
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}
@@ -1899,9 +1879,7 @@ func (a *FakeApiService) TestQueryParameterCollectionFormatExecute(r ApiTestQuer
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPut
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "FakeApiService.TestQueryParameterCollectionFormat")
@@ -1962,7 +1940,7 @@ func (a *FakeApiService) TestQueryParameterCollectionFormatExecute(r ApiTestQuer
 	if localVarHTTPHeaderAccept != "" {
 		localVarHeaderParams["Accept"] = localVarHTTPHeaderAccept
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}

samples/client/petstore/go/go-petstore/api_fake_classname_tags123.go

@@ -80,9 +80,7 @@ func (a *FakeClassnameTags123ApiService) TestClassnameExecute(r ApiTestClassname
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPatch
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  Client
 	)
 
@@ -133,7 +131,7 @@ func (a *FakeClassnameTags123ApiService) TestClassnameExecute(r ApiTestClassname
 			}
 		}
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}

samples/client/petstore/go/go-petstore/api_pet.go

@@ -183,9 +183,7 @@ func (a *PetApiService) AddPetExecute(r ApiAddPetRequest) (*_nethttp.Response, e
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPost
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "PetApiService.AddPet")
@@ -221,7 +219,7 @@ func (a *PetApiService) AddPetExecute(r ApiAddPetRequest) (*_nethttp.Response, e
 	}
 	// body params
 	localVarPostBody = r.body
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}
@@ -285,9 +283,7 @@ func (a *PetApiService) DeletePetExecute(r ApiDeletePetRequest) (*_nethttp.Respo
 	var (
 		localVarHTTPMethod   = _nethttp.MethodDelete
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "PetApiService.DeletePet")
@@ -322,7 +318,7 @@ func (a *PetApiService) DeletePetExecute(r ApiDeletePetRequest) (*_nethttp.Respo
 	if r.apiKey != nil {
 		localVarHeaderParams["api_key"] = parameterToString(*r.apiKey, "")
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}
@@ -387,9 +383,7 @@ func (a *PetApiService) FindPetsByStatusExecute(r ApiFindPetsByStatusRequest) ([
 	var (
 		localVarHTTPMethod   = _nethttp.MethodGet
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  []Pet
 	)
 
@@ -425,7 +419,7 @@ func (a *PetApiService) FindPetsByStatusExecute(r ApiFindPetsByStatusRequest) ([
 	if localVarHTTPHeaderAccept != "" {
 		localVarHeaderParams["Accept"] = localVarHTTPHeaderAccept
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}
@@ -502,9 +496,7 @@ func (a *PetApiService) FindPetsByTagsExecute(r ApiFindPetsByTagsRequest) ([]Pet
 	var (
 		localVarHTTPMethod   = _nethttp.MethodGet
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  []Pet
 	)
 
@@ -540,7 +532,7 @@ func (a *PetApiService) FindPetsByTagsExecute(r ApiFindPetsByTagsRequest) ([]Pet
 	if localVarHTTPHeaderAccept != "" {
 		localVarHeaderParams["Accept"] = localVarHTTPHeaderAccept
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}
@@ -611,9 +603,7 @@ func (a *PetApiService) GetPetByIdExecute(r ApiGetPetByIdRequest) (Pet, *_nethtt
 	var (
 		localVarHTTPMethod   = _nethttp.MethodGet
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  Pet
 	)
 
@@ -660,7 +650,7 @@ func (a *PetApiService) GetPetByIdExecute(r ApiGetPetByIdRequest) (Pet, *_nethtt
 			}
 		}
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}
@@ -731,9 +721,7 @@ func (a *PetApiService) UpdatePetExecute(r ApiUpdatePetRequest) (*_nethttp.Respo
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPut
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "PetApiService.UpdatePet")
@@ -769,7 +757,7 @@ func (a *PetApiService) UpdatePetExecute(r ApiUpdatePetRequest) (*_nethttp.Respo
 	}
 	// body params
 	localVarPostBody = r.body
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}
@@ -840,9 +828,7 @@ func (a *PetApiService) UpdatePetWithFormExecute(r ApiUpdatePetWithFormRequest)
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPost
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "PetApiService.UpdatePetWithForm")
@@ -880,7 +866,7 @@ func (a *PetApiService) UpdatePetWithFormExecute(r ApiUpdatePetWithFormRequest)
 	if r.status != nil {
 		localVarFormParams.Add("status", parameterToString(*r.status, ""))
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}
@@ -952,9 +938,7 @@ func (a *PetApiService) UploadFileExecute(r ApiUploadFileRequest) (ApiResponse,
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPost
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  ApiResponse
 	)
 
@@ -990,18 +974,24 @@ func (a *PetApiService) UploadFileExecute(r ApiUploadFileRequest) (ApiResponse,
 	if r.additionalMetadata != nil {
 		localVarFormParams.Add("additionalMetadata", parameterToString(*r.additionalMetadata, ""))
 	}
-	localVarFormFileName = "file"
+	var fileLocalVarFormFileName string
-	var localVarFile *os.File
+	var fileLocalVarFileName     string
+	var fileLocalVarFileBytes    []byte
+
+	fileLocalVarFormFileName = "file"
+
+	var fileLocalVarFile *os.File
 	if r.file != nil {
-		localVarFile = *r.file
+		fileLocalVarFile = *r.file
 	}
-	if localVarFile != nil {
+	if fileLocalVarFile != nil {
-		fbs, _ := _ioutil.ReadAll(localVarFile)
+		fbs, _ := _ioutil.ReadAll(fileLocalVarFile)
-		localVarFileBytes = fbs
+		fileLocalVarFileBytes = fbs
-		localVarFileName = localVarFile.Name()
+		fileLocalVarFileName = fileLocalVarFile.Name()
-		localVarFile.Close()
+		fileLocalVarFile.Close()
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	formFiles = append(formFiles, formFile{fileBytes: fileLocalVarFileBytes, fileName: fileLocalVarFileName, formFileName: fileLocalVarFormFileName})
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}
@@ -1082,9 +1072,7 @@ func (a *PetApiService) UploadFileWithRequiredFileExecute(r ApiUploadFileWithReq
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPost
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  ApiResponse
 	)
 
@@ -1123,15 +1111,21 @@ func (a *PetApiService) UploadFileWithRequiredFileExecute(r ApiUploadFileWithReq
 	if r.additionalMetadata != nil {
 		localVarFormParams.Add("additionalMetadata", parameterToString(*r.additionalMetadata, ""))
 	}
-	localVarFormFileName = "requiredFile"
+	var requiredFileLocalVarFormFileName string
-	localVarFile := *r.requiredFile
+	var requiredFileLocalVarFileName     string
-	if localVarFile != nil {
+	var requiredFileLocalVarFileBytes    []byte
-		fbs, _ := _ioutil.ReadAll(localVarFile)
+
-		localVarFileBytes = fbs
+	requiredFileLocalVarFormFileName = "requiredFile"
-		localVarFileName = localVarFile.Name()
+
-		localVarFile.Close()
+	requiredFileLocalVarFile := *r.requiredFile
+	if requiredFileLocalVarFile != nil {
+		fbs, _ := _ioutil.ReadAll(requiredFileLocalVarFile)
+		requiredFileLocalVarFileBytes = fbs
+		requiredFileLocalVarFileName = requiredFileLocalVarFile.Name()
+		requiredFileLocalVarFile.Close()
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	formFiles = append(formFiles, formFile{fileBytes: requiredFileLocalVarFileBytes, fileName: requiredFileLocalVarFileName, formFileName: requiredFileLocalVarFormFileName})
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}

samples/client/petstore/go/go-petstore/api_store.go

@@ -118,9 +118,7 @@ func (a *StoreApiService) DeleteOrderExecute(r ApiDeleteOrderRequest) (*_nethttp
 	var (
 		localVarHTTPMethod   = _nethttp.MethodDelete
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "StoreApiService.DeleteOrder")
@@ -152,7 +150,7 @@ func (a *StoreApiService) DeleteOrderExecute(r ApiDeleteOrderRequest) (*_nethttp
 	if localVarHTTPHeaderAccept != "" {
 		localVarHeaderParams["Accept"] = localVarHTTPHeaderAccept
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}
@@ -211,9 +209,7 @@ func (a *StoreApiService) GetInventoryExecute(r ApiGetInventoryRequest) (map[str
 	var (
 		localVarHTTPMethod   = _nethttp.MethodGet
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  map[string]int32
 	)
 
@@ -259,7 +255,7 @@ func (a *StoreApiService) GetInventoryExecute(r ApiGetInventoryRequest) (map[str
 			}
 		}
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}
@@ -330,9 +326,7 @@ func (a *StoreApiService) GetOrderByIdExecute(r ApiGetOrderByIdRequest) (Order,
 	var (
 		localVarHTTPMethod   = _nethttp.MethodGet
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  Order
 	)
 
@@ -371,7 +365,7 @@ func (a *StoreApiService) GetOrderByIdExecute(r ApiGetOrderByIdRequest) (Order,
 	if localVarHTTPHeaderAccept != "" {
 		localVarHeaderParams["Accept"] = localVarHTTPHeaderAccept
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}
@@ -443,9 +437,7 @@ func (a *StoreApiService) PlaceOrderExecute(r ApiPlaceOrderRequest) (Order, *_ne
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPost
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  Order
 	)
 
@@ -482,7 +474,7 @@ func (a *StoreApiService) PlaceOrderExecute(r ApiPlaceOrderRequest) (Order, *_ne
 	}
 	// body params
 	localVarPostBody = r.body
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}

samples/client/petstore/go/go-petstore/api_user.go

@@ -165,9 +165,7 @@ func (a *UserApiService) CreateUserExecute(r ApiCreateUserRequest) (*_nethttp.Re
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPost
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "UserApiService.CreateUser")
@@ -203,7 +201,7 @@ func (a *UserApiService) CreateUserExecute(r ApiCreateUserRequest) (*_nethttp.Re
 	}
 	// body params
 	localVarPostBody = r.body
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}
@@ -265,9 +263,7 @@ func (a *UserApiService) CreateUsersWithArrayInputExecute(r ApiCreateUsersWithAr
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPost
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "UserApiService.CreateUsersWithArrayInput")
@@ -303,7 +299,7 @@ func (a *UserApiService) CreateUsersWithArrayInputExecute(r ApiCreateUsersWithAr
 	}
 	// body params
 	localVarPostBody = r.body
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}
@@ -365,9 +361,7 @@ func (a *UserApiService) CreateUsersWithListInputExecute(r ApiCreateUsersWithLis
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPost
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "UserApiService.CreateUsersWithListInput")
@@ -403,7 +397,7 @@ func (a *UserApiService) CreateUsersWithListInputExecute(r ApiCreateUsersWithLis
 	}
 	// body params
 	localVarPostBody = r.body
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}
@@ -464,9 +458,7 @@ func (a *UserApiService) DeleteUserExecute(r ApiDeleteUserRequest) (*_nethttp.Re
 	var (
 		localVarHTTPMethod   = _nethttp.MethodDelete
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "UserApiService.DeleteUser")
@@ -498,7 +490,7 @@ func (a *UserApiService) DeleteUserExecute(r ApiDeleteUserRequest) (*_nethttp.Re
 	if localVarHTTPHeaderAccept != "" {
 		localVarHeaderParams["Accept"] = localVarHTTPHeaderAccept
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}
@@ -558,9 +550,7 @@ func (a *UserApiService) GetUserByNameExecute(r ApiGetUserByNameRequest) (User,
 	var (
 		localVarHTTPMethod   = _nethttp.MethodGet
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  User
 	)
 
@@ -593,7 +583,7 @@ func (a *UserApiService) GetUserByNameExecute(r ApiGetUserByNameRequest) (User,
 	if localVarHTTPHeaderAccept != "" {
 		localVarHeaderParams["Accept"] = localVarHTTPHeaderAccept
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}
@@ -671,9 +661,7 @@ func (a *UserApiService) LoginUserExecute(r ApiLoginUserRequest) (string, *_neth
 	var (
 		localVarHTTPMethod   = _nethttp.MethodGet
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  string
 	)
 
@@ -713,7 +701,7 @@ func (a *UserApiService) LoginUserExecute(r ApiLoginUserRequest) (string, *_neth
 	if localVarHTTPHeaderAccept != "" {
 		localVarHeaderParams["Accept"] = localVarHTTPHeaderAccept
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}
@@ -778,9 +766,7 @@ func (a *UserApiService) LogoutUserExecute(r ApiLogoutUserRequest) (*_nethttp.Re
 	var (
 		localVarHTTPMethod   = _nethttp.MethodGet
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "UserApiService.LogoutUser")
@@ -811,7 +797,7 @@ func (a *UserApiService) LogoutUserExecute(r ApiLogoutUserRequest) (*_nethttp.Re
 	if localVarHTTPHeaderAccept != "" {
 		localVarHeaderParams["Accept"] = localVarHTTPHeaderAccept
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}
@@ -878,9 +864,7 @@ func (a *UserApiService) UpdateUserExecute(r ApiUpdateUserRequest) (*_nethttp.Re
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPut
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "UserApiService.UpdateUser")
@@ -917,7 +901,7 @@ func (a *UserApiService) UpdateUserExecute(r ApiUpdateUserRequest) (*_nethttp.Re
 	}
 	// body params
 	localVarPostBody = r.body
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}

samples/client/petstore/go/go-petstore/client.go

@@ -204,6 +204,12 @@ func (c *APIClient) GetConfig() *Configuration {
 	return c.cfg
 }
 
+type formFile struct {
+		fileBytes []byte
+		fileName string
+		formFileName string
+}
+
 // prepareRequest build the request
 func (c *APIClient) prepareRequest(
 	ctx context.Context,
@@ -212,9 +218,7 @@ func (c *APIClient) prepareRequest(
 	headerParams map[string]string,
 	queryParams url.Values,
 	formParams url.Values,
-	formFileName string,
+	formFiles []formFile) (localVarRequest *http.Request, err error) {
-	fileName string,
-	fileBytes []byte) (localVarRequest *http.Request, err error) {
 
 	var body *bytes.Buffer
 
@@ -233,7 +237,7 @@ func (c *APIClient) prepareRequest(
 	}
 
 	// add form parameters and file if available.
-	if strings.HasPrefix(headerParams["Content-Type"], "multipart/form-data") && len(formParams) > 0 || (len(fileBytes) > 0 && fileName != "") {
+	if strings.HasPrefix(headerParams["Content-Type"], "multipart/form-data") && len(formParams) > 0 || (len(formFiles) > 0) {
 		if body != nil {
 			return nil, errors.New("Cannot specify postBody and multipart form at the same time.")
 		}
@@ -252,18 +256,19 @@ func (c *APIClient) prepareRequest(
 				}
 			}
 		}
-		if len(fileBytes) > 0 && fileName != "" {
+		for _, formFile := range formFiles {
+			if len(formFile.fileBytes) > 0 && formFile.fileName != "" {
 				w.Boundary()
-			//_, fileNm := filepath.Split(fileName)
+				part, err := w.CreateFormFile(formFile.formFileName, filepath.Base(formFile.fileName))
-			part, err := w.CreateFormFile(formFileName, filepath.Base(fileName))
 				if err != nil {
 						return nil, err
 				}
-			_, err = part.Write(fileBytes)
+				_, err = part.Write(formFile.fileBytes)
 				if err != nil {
 						return nil, err
 				}
 			}
+		}
 
 		// Set the Boundary in the Content-Type
 		headerParams["Content-Type"] = w.FormDataContentType()

samples/openapi3/client/extensions/x-auth-id-alias/go-experimental/api_usage.go

@@ -57,9 +57,7 @@ func (a *UsageApiService) AnyKeyExecute(r ApiAnyKeyRequest) (map[string]interfac
 	var (
 		localVarHTTPMethod   = _nethttp.MethodGet
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  map[string]interface{}
 	)
 
@@ -119,7 +117,7 @@ func (a *UsageApiService) AnyKeyExecute(r ApiAnyKeyRequest) (map[string]interfac
 			}
 		}
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}
@@ -187,9 +185,7 @@ func (a *UsageApiService) BothKeysExecute(r ApiBothKeysRequest) (map[string]inte
 	var (
 		localVarHTTPMethod   = _nethttp.MethodGet
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  map[string]interface{}
 	)
 
@@ -249,7 +245,7 @@ func (a *UsageApiService) BothKeysExecute(r ApiBothKeysRequest) (map[string]inte
 			}
 		}
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}
@@ -317,9 +313,7 @@ func (a *UsageApiService) KeyInHeaderExecute(r ApiKeyInHeaderRequest) (map[strin
 	var (
 		localVarHTTPMethod   = _nethttp.MethodGet
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  map[string]interface{}
 	)
 
@@ -365,7 +359,7 @@ func (a *UsageApiService) KeyInHeaderExecute(r ApiKeyInHeaderRequest) (map[strin
 			}
 		}
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}
@@ -433,9 +427,7 @@ func (a *UsageApiService) KeyInQueryExecute(r ApiKeyInQueryRequest) (map[string]
 	var (
 		localVarHTTPMethod   = _nethttp.MethodGet
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  map[string]interface{}
 	)
 
@@ -481,7 +473,7 @@ func (a *UsageApiService) KeyInQueryExecute(r ApiKeyInQueryRequest) (map[string]
 			}
 		}
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}

samples/openapi3/client/extensions/x-auth-id-alias/go-experimental/client.go

@@ -189,6 +189,12 @@ func (c *APIClient) GetConfig() *Configuration {
 	return c.cfg
 }
 
+type formFile struct {
+		fileBytes []byte
+		fileName string
+		formFileName string
+}
+
 // prepareRequest build the request
 func (c *APIClient) prepareRequest(
 	ctx context.Context,
@@ -197,9 +203,7 @@ func (c *APIClient) prepareRequest(
 	headerParams map[string]string,
 	queryParams url.Values,
 	formParams url.Values,
-	formFileName string,
+	formFiles []formFile) (localVarRequest *http.Request, err error) {
-	fileName string,
-	fileBytes []byte) (localVarRequest *http.Request, err error) {
 
 	var body *bytes.Buffer
 
@@ -218,7 +222,7 @@ func (c *APIClient) prepareRequest(
 	}
 
 	// add form parameters and file if available.
-	if strings.HasPrefix(headerParams["Content-Type"], "multipart/form-data") && len(formParams) > 0 || (len(fileBytes) > 0 && fileName != "") {
+	if strings.HasPrefix(headerParams["Content-Type"], "multipart/form-data") && len(formParams) > 0 || (len(formFiles) > 0) {
 		if body != nil {
 			return nil, errors.New("Cannot specify postBody and multipart form at the same time.")
 		}
@@ -237,18 +241,19 @@ func (c *APIClient) prepareRequest(
 				}
 			}
 		}
-		if len(fileBytes) > 0 && fileName != "" {
+		for _, formFile := range formFiles {
+			if len(formFile.fileBytes) > 0 && formFile.fileName != "" {
 				w.Boundary()
-			//_, fileNm := filepath.Split(fileName)
+				part, err := w.CreateFormFile(formFile.formFileName, filepath.Base(formFile.fileName))
-			part, err := w.CreateFormFile(formFileName, filepath.Base(fileName))
 				if err != nil {
 						return nil, err
 				}
-			_, err = part.Write(fileBytes)
+				_, err = part.Write(formFile.fileBytes)
 				if err != nil {
 						return nil, err
 				}
 			}
+		}
 
 		// Set the Boundary in the Content-Type
 		headerParams["Content-Type"] = w.FormDataContentType()

samples/openapi3/client/features/mulitple-data-in-forms/.gitignore

@@ -0,0 +1,24 @@
+# Compiled Object files, Static and Dynamic libs (Shared Objects)
+*.o
+*.a
+*.so
+
+# Folders
+_obj
+_test
+
+# Architecture specific extensions/prefixes
+*.[568vq]
+[568vq].out
+
+*.cgo1.go
+*.cgo2.c
+_cgo_defun.c
+_cgo_gotypes.go
+_cgo_export.*
+
+_testmain.go
+
+*.exe
+*.test
+*.prof

samples/openapi3/client/features/mulitple-data-in-forms/.openapi-generator-ignore

@@ -0,0 +1,23 @@
+# OpenAPI Generator Ignore
+# Generated by openapi-generator https://github.com/openapitools/openapi-generator
+
+# Use this file to prevent files from being overwritten by the generator.
+# The patterns follow closely to .gitignore or .dockerignore.
+
+# As an example, the C# client generator defines ApiClient.cs.
+# You can make changes and tell OpenAPI Generator to ignore just this file by uncommenting the following line:
+#ApiClient.cs
+
+# You can match any string of characters against a directory, file or extension with a single asterisk (*):
+#foo/*/qux
+# The above matches foo/bar/qux and foo/baz/qux, but not foo/bar/baz/qux
+
+# You can recursively match patterns against a directory, file or extension with a double asterisk (**):
+#foo/**/qux
+# This matches foo/bar/qux, foo/baz/qux, and foo/bar/baz/qux
+
+# You can also negate patterns with an exclamation (!).
+# For example, you can ignore all files in a docs folder with the file extension .md:
+#docs/*.md
+# Then explicitly reverse the ignore rule for a single file:
+#!docs/README.md

samples/openapi3/client/features/mulitple-data-in-forms/.openapi-generator/FILES

@@ -0,0 +1,16 @@
+.gitignore
+.openapi-generator-ignore
+.travis.yml
+README.md
+api/openapi.yaml
+api_default.go
+client.go
+configuration.go
+docs/ApiResponse.md
+docs/DefaultApi.md
+git_push.sh
+go.mod
+go.sum
+model_api_response.go
+response.go
+utils.go

samples/openapi3/client/features/mulitple-data-in-forms/.openapi-generator/VERSION

@@ -0,0 +1 @@
+5.3.1-SNAPSHOT

samples/openapi3/client/features/mulitple-data-in-forms/.travis.yml

@@ -0,0 +1,8 @@
+language: go
+
+install:
+  - go get -d -v .
+
+script:
+  - go build -v ./
+

samples/openapi3/client/features/mulitple-data-in-forms/README.md

@@ -0,0 +1,113 @@
+# Go API client for openapi
+
+This is a sample server with a single endpoint that accepts two files via a multipart/form-data POST request.
+
+## Overview
+This API client was generated by the [OpenAPI Generator](https://openapi-generator.tech) project.  By using the [OpenAPI-spec](https://www.openapis.org/) from a remote server, you can easily generate an API client.
+
+- API version: 1.0.0
+- Package version: 1.0.0
+- Build package: org.openapitools.codegen.languages.GoClientCodegen
+
+## Installation
+
+Install the following dependencies:
+
+```shell
+go get github.com/stretchr/testify/assert
+go get golang.org/x/oauth2
+go get golang.org/x/net/context
+```
+
+Put the package under your project folder and add the following in import:
+
+```golang
+import sw "./openapi"
+```
+
+To use a proxy, set the environment variable `HTTP_PROXY`:
+
+```golang
+os.Setenv("HTTP_PROXY", "http://proxy_name:proxy_port")
+```
+
+## Configuration of Server URL
+
+Default configuration comes with `Servers` field that contains server objects as defined in the OpenAPI specification.
+
+### Select Server Configuration
+
+For using other server than the one defined on index 0 set context value `sw.ContextServerIndex` of type `int`.
+
+```golang
+ctx := context.WithValue(context.Background(), sw.ContextServerIndex, 1)
+```
+
+### Templated Server URL
+
+Templated server URL is formatted using default variables from configuration or from context value `sw.ContextServerVariables` of type `map[string]string`.
+
+```golang
+ctx := context.WithValue(context.Background(), sw.ContextServerVariables, map[string]string{
+	"basePath": "v2",
+})
+```
+
+Note, enum values are always validated and all unused variables are silently ignored.
+
+### URLs Configuration per Operation
+
+Each operation can use different server URL defined using `OperationServers` map in the `Configuration`.
+An operation is uniquely identified by `"{classname}Service.{nickname}"` string.
+Similar rules for overriding default operation server index and variables applies by using `sw.ContextOperationServerIndices` and `sw.ContextOperationServerVariables` context maps.
+
+```
+ctx := context.WithValue(context.Background(), sw.ContextOperationServerIndices, map[string]int{
+	"{classname}Service.{nickname}": 2,
+})
+ctx = context.WithValue(context.Background(), sw.ContextOperationServerVariables, map[string]map[string]string{
+	"{classname}Service.{nickname}": {
+		"port": "8443",
+	},
+})
+```
+
+## Documentation for API Endpoints
+
+All URIs are relative to *http://example.com*
+
+Class | Method | HTTP request | Description
+------------ | ------------- | ------------- | -------------
+*DefaultApi* | [**UploadFiles**](docs/DefaultApi.md#uploadfiles) | **Post** /uploadFiles | uploads two files
+
+
+## Documentation For Models
+
+ - [ApiResponse](docs/ApiResponse.md)
+
+
+## Documentation For Authorization
+
+ Endpoints do not require authorization.
+
+
+## Documentation for Utility Methods
+
+Due to the fact that model structure members are all pointers, this package contains
+a number of utility functions to easily obtain pointers to values of basic types.
+Each of these functions takes a value of the given basic type and returns a pointer to it:
+
+* `PtrBool`
+* `PtrInt`
+* `PtrInt32`
+* `PtrInt64`
+* `PtrFloat`
+* `PtrFloat32`
+* `PtrFloat64`
+* `PtrString`
+* `PtrTime`
+
+## Author
+
+
+

samples/openapi3/client/features/mulitple-data-in-forms/api/openapi.yaml

@@ -0,0 +1,73 @@
+openapi: 3.0.0
+info:
+  description: This is a sample server with a single endpoint that accepts two files
+    via a multipart/form-data POST request.
+  license:
+    name: Apache-2.0
+    url: https://www.apache.org/licenses/LICENSE-2.0.html
+  title: Multiple Files via form-data
+  version: 1.0.0
+servers:
+- url: http://example.com
+paths:
+  /uploadFiles:
+    post:
+      operationId: uploadFiles
+      requestBody:
+        $ref: '#/components/requestBodies/inline_object'
+        content:
+          multipart/form-data:
+            schema:
+              properties:
+                file:
+                  description: file to upload
+                  format: binary
+                  type: string
+                secondFile:
+                  description: another file to upload
+                  format: binary
+                  type: string
+              type: object
+      responses:
+        "200":
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/ApiResponse'
+          description: successful operation
+      summary: uploads two files
+components:
+  requestBodies:
+    inline_object:
+      content:
+        multipart/form-data:
+          schema:
+            $ref: '#/components/schemas/inline_object'
+  schemas:
+    ApiResponse:
+      description: Describes the result of uploading files
+      example:
+        code: 0
+        type: type
+        message: message
+      properties:
+        code:
+          format: int32
+          type: integer
+        type:
+          type: string
+        message:
+          type: string
+      title: An uploaded response
+      type: object
+    inline_object:
+      properties:
+        file:
+          description: file to upload
+          format: binary
+          type: string
+        secondFile:
+          description: another file to upload
+          format: binary
+          type: string
+      type: object

samples/openapi3/client/features/mulitple-data-in-forms/api_default.go

@@ -0,0 +1,172 @@
+/*
+Multiple Files via form-data
+
+This is a sample server with a single endpoint that accepts two files via a multipart/form-data POST request.
+
+API version: 1.0.0
+*/
+
+// Code generated by OpenAPI Generator (https://openapi-generator.tech); DO NOT EDIT.
+
+package openapi
+
+import (
+	"bytes"
+	_context "context"
+	_ioutil "io/ioutil"
+	_nethttp "net/http"
+	_neturl "net/url"
+	"os"
+)
+
+// Linger please
+var (
+	_ _context.Context
+)
+
+// DefaultApiService DefaultApi service
+type DefaultApiService service
+
+type ApiUploadFilesRequest struct {
+	ctx _context.Context
+	ApiService *DefaultApiService
+	file **os.File
+	secondFile **os.File
+}
+
+// file to upload
+func (r ApiUploadFilesRequest) File(file *os.File) ApiUploadFilesRequest {
+	r.file = &file
+	return r
+}
+// another file to upload
+func (r ApiUploadFilesRequest) SecondFile(secondFile *os.File) ApiUploadFilesRequest {
+	r.secondFile = &secondFile
+	return r
+}
+
+func (r ApiUploadFilesRequest) Execute() (ApiResponse, *_nethttp.Response, error) {
+	return r.ApiService.UploadFilesExecute(r)
+}
+
+/*
+UploadFiles uploads two files
+
+ @param ctx _context.Context - for authentication, logging, cancellation, deadlines, tracing, etc. Passed from http.Request or context.Background().
+ @return ApiUploadFilesRequest
+*/
+func (a *DefaultApiService) UploadFiles(ctx _context.Context) ApiUploadFilesRequest {
+	return ApiUploadFilesRequest{
+		ApiService: a,
+		ctx: ctx,
+	}
+}
+
+// Execute executes the request
+//  @return ApiResponse
+func (a *DefaultApiService) UploadFilesExecute(r ApiUploadFilesRequest) (ApiResponse, *_nethttp.Response, error) {
+	var (
+		localVarHTTPMethod   = _nethttp.MethodPost
+		localVarPostBody     interface{}
+		formFiles            []formFile
+		localVarReturnValue  ApiResponse
+	)
+
+	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "DefaultApiService.UploadFiles")
+	if err != nil {
+		return localVarReturnValue, nil, GenericOpenAPIError{error: err.Error()}
+	}
+
+	localVarPath := localBasePath + "/uploadFiles"
+
+	localVarHeaderParams := make(map[string]string)
+	localVarQueryParams := _neturl.Values{}
+	localVarFormParams := _neturl.Values{}
+
+	// to determine the Content-Type header
+	localVarHTTPContentTypes := []string{"multipart/form-data"}
+
+	// set Content-Type header
+	localVarHTTPContentType := selectHeaderContentType(localVarHTTPContentTypes)
+	if localVarHTTPContentType != "" {
+		localVarHeaderParams["Content-Type"] = localVarHTTPContentType
+	}
+
+	// to determine the Accept header
+	localVarHTTPHeaderAccepts := []string{"application/json"}
+
+	// set Accept header
+	localVarHTTPHeaderAccept := selectHeaderAccept(localVarHTTPHeaderAccepts)
+	if localVarHTTPHeaderAccept != "" {
+		localVarHeaderParams["Accept"] = localVarHTTPHeaderAccept
+	}
+	var fileLocalVarFormFileName string
+	var fileLocalVarFileName     string
+	var fileLocalVarFileBytes    []byte
+
+	fileLocalVarFormFileName = "file"
+
+	var fileLocalVarFile *os.File
+	if r.file != nil {
+		fileLocalVarFile = *r.file
+	}
+	if fileLocalVarFile != nil {
+		fbs, _ := _ioutil.ReadAll(fileLocalVarFile)
+		fileLocalVarFileBytes = fbs
+		fileLocalVarFileName = fileLocalVarFile.Name()
+		fileLocalVarFile.Close()
+	}
+	formFiles = append(formFiles, formFile{fileBytes: fileLocalVarFileBytes, fileName: fileLocalVarFileName, formFileName: fileLocalVarFormFileName})
+	var secondFileLocalVarFormFileName string
+	var secondFileLocalVarFileName     string
+	var secondFileLocalVarFileBytes    []byte
+
+	secondFileLocalVarFormFileName = "secondFile"
+
+	var secondFileLocalVarFile *os.File
+	if r.secondFile != nil {
+		secondFileLocalVarFile = *r.secondFile
+	}
+	if secondFileLocalVarFile != nil {
+		fbs, _ := _ioutil.ReadAll(secondFileLocalVarFile)
+		secondFileLocalVarFileBytes = fbs
+		secondFileLocalVarFileName = secondFileLocalVarFile.Name()
+		secondFileLocalVarFile.Close()
+	}
+	formFiles = append(formFiles, formFile{fileBytes: secondFileLocalVarFileBytes, fileName: secondFileLocalVarFileName, formFileName: secondFileLocalVarFormFileName})
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
+	if err != nil {
+		return localVarReturnValue, nil, err
+	}
+
+	localVarHTTPResponse, err := a.client.callAPI(req)
+	if err != nil || localVarHTTPResponse == nil {
+		return localVarReturnValue, localVarHTTPResponse, err
+	}
+
+	localVarBody, err := _ioutil.ReadAll(localVarHTTPResponse.Body)
+	localVarHTTPResponse.Body.Close()
+	localVarHTTPResponse.Body = _ioutil.NopCloser(bytes.NewBuffer(localVarBody))
+	if err != nil {
+		return localVarReturnValue, localVarHTTPResponse, err
+	}
+
+	if localVarHTTPResponse.StatusCode >= 300 {
+		newErr := GenericOpenAPIError{
+			body:  localVarBody,
+			error: localVarHTTPResponse.Status,
+		}
+		return localVarReturnValue, localVarHTTPResponse, newErr
+	}
+
+	err = a.client.decode(&localVarReturnValue, localVarBody, localVarHTTPResponse.Header.Get("Content-Type"))
+	if err != nil {
+		newErr := GenericOpenAPIError{
+			body:  localVarBody,
+			error: err.Error(),
+		}
+		return localVarReturnValue, localVarHTTPResponse, newErr
+	}
+
+	return localVarReturnValue, localVarHTTPResponse, nil
+}

samples/openapi3/client/features/mulitple-data-in-forms/client.go

@@ -0,0 +1,553 @@
+/*
+Multiple Files via form-data
+
+This is a sample server with a single endpoint that accepts two files via a multipart/form-data POST request.
+
+API version: 1.0.0
+*/
+
+// Code generated by OpenAPI Generator (https://openapi-generator.tech); DO NOT EDIT.
+
+package openapi
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"encoding/xml"
+	"errors"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"log"
+	"mime/multipart"
+	"net/http"
+	"net/http/httputil"
+	"net/url"
+	"os"
+	"path/filepath"
+	"reflect"
+	"regexp"
+	"strconv"
+	"strings"
+	"time"
+	"unicode/utf8"
+
+	"golang.org/x/oauth2"
+)
+
+var (
+	jsonCheck = regexp.MustCompile(`(?i:(?:application|text)/(?:vnd\.[^;]+\+)?json)`)
+	xmlCheck  = regexp.MustCompile(`(?i:(?:application|text)/xml)`)
+)
+
+// APIClient manages communication with the Multiple Files via form-data API v1.0.0
+// In most cases there should be only one, shared, APIClient.
+type APIClient struct {
+	cfg    *Configuration
+	common service // Reuse a single struct instead of allocating one for each service on the heap.
+
+	// API Services
+
+	DefaultApi *DefaultApiService
+}
+
+type service struct {
+	client *APIClient
+}
+
+// NewAPIClient creates a new API client. Requires a userAgent string describing your application.
+// optionally a custom http.Client to allow for advanced features such as caching.
+func NewAPIClient(cfg *Configuration) *APIClient {
+	if cfg.HTTPClient == nil {
+		cfg.HTTPClient = http.DefaultClient
+	}
+
+	c := &APIClient{}
+	c.cfg = cfg
+	c.common.client = c
+
+	// API Services
+	c.DefaultApi = (*DefaultApiService)(&c.common)
+
+	return c
+}
+
+func atoi(in string) (int, error) {
+	return strconv.Atoi(in)
+}
+
+// selectHeaderContentType select a content type from the available list.
+func selectHeaderContentType(contentTypes []string) string {
+	if len(contentTypes) == 0 {
+		return ""
+	}
+	if contains(contentTypes, "application/json") {
+		return "application/json"
+	}
+	return contentTypes[0] // use the first content type specified in 'consumes'
+}
+
+// selectHeaderAccept join all accept types and return
+func selectHeaderAccept(accepts []string) string {
+	if len(accepts) == 0 {
+		return ""
+	}
+
+	if contains(accepts, "application/json") {
+		return "application/json"
+	}
+
+	return strings.Join(accepts, ",")
+}
+
+// contains is a case insensitive match, finding needle in a haystack
+func contains(haystack []string, needle string) bool {
+	for _, a := range haystack {
+		if strings.ToLower(a) == strings.ToLower(needle) {
+			return true
+		}
+	}
+	return false
+}
+
+// Verify optional parameters are of the correct type.
+func typeCheckParameter(obj interface{}, expected string, name string) error {
+	// Make sure there is an object.
+	if obj == nil {
+		return nil
+	}
+
+	// Check the type is as expected.
+	if reflect.TypeOf(obj).String() != expected {
+		return fmt.Errorf("Expected %s to be of type %s but received %s.", name, expected, reflect.TypeOf(obj).String())
+	}
+	return nil
+}
+
+// parameterToString convert interface{} parameters to string, using a delimiter if format is provided.
+func parameterToString(obj interface{}, collectionFormat string) string {
+	var delimiter string
+
+	switch collectionFormat {
+	case "pipes":
+		delimiter = "|"
+	case "ssv":
+		delimiter = " "
+	case "tsv":
+		delimiter = "\t"
+	case "csv":
+		delimiter = ","
+	}
+
+	if reflect.TypeOf(obj).Kind() == reflect.Slice {
+		return strings.Trim(strings.Replace(fmt.Sprint(obj), " ", delimiter, -1), "[]")
+	} else if t, ok := obj.(time.Time); ok {
+		return t.Format(time.RFC3339)
+	}
+
+	return fmt.Sprintf("%v", obj)
+}
+
+// helper for converting interface{} parameters to json strings
+func parameterToJson(obj interface{}) (string, error) {
+	jsonBuf, err := json.Marshal(obj)
+	if err != nil {
+		return "", err
+	}
+	return string(jsonBuf), err
+}
+
+// callAPI do the request.
+func (c *APIClient) callAPI(request *http.Request) (*http.Response, error) {
+	if c.cfg.Debug {
+		dump, err := httputil.DumpRequestOut(request, true)
+		if err != nil {
+			return nil, err
+		}
+		log.Printf("\n%s\n", string(dump))
+	}
+
+	resp, err := c.cfg.HTTPClient.Do(request)
+	if err != nil {
+		return resp, err
+	}
+
+	if c.cfg.Debug {
+		dump, err := httputil.DumpResponse(resp, true)
+		if err != nil {
+			return resp, err
+		}
+		log.Printf("\n%s\n", string(dump))
+	}
+	return resp, err
+}
+
+// Allow modification of underlying config for alternate implementations and testing
+// Caution: modifying the configuration while live can cause data races and potentially unwanted behavior
+func (c *APIClient) GetConfig() *Configuration {
+	return c.cfg
+}
+
+type formFile struct {
+		fileBytes []byte
+		fileName string
+		formFileName string
+}
+
+// prepareRequest build the request
+func (c *APIClient) prepareRequest(
+	ctx context.Context,
+	path string, method string,
+	postBody interface{},
+	headerParams map[string]string,
+	queryParams url.Values,
+	formParams url.Values,
+	formFiles []formFile) (localVarRequest *http.Request, err error) {
+
+	var body *bytes.Buffer
+
+	// Detect postBody type and post.
+	if postBody != nil {
+		contentType := headerParams["Content-Type"]
+		if contentType == "" {
+			contentType = detectContentType(postBody)
+			headerParams["Content-Type"] = contentType
+		}
+
+		body, err = setBody(postBody, contentType)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	// add form parameters and file if available.
+	if strings.HasPrefix(headerParams["Content-Type"], "multipart/form-data") && len(formParams) > 0 || (len(formFiles) > 0) {
+		if body != nil {
+			return nil, errors.New("Cannot specify postBody and multipart form at the same time.")
+		}
+		body = &bytes.Buffer{}
+		w := multipart.NewWriter(body)
+
+		for k, v := range formParams {
+			for _, iv := range v {
+				if strings.HasPrefix(k, "@") { // file
+					err = addFile(w, k[1:], iv)
+					if err != nil {
+						return nil, err
+					}
+				} else { // form value
+					w.WriteField(k, iv)
+				}
+			}
+		}
+		for _, formFile := range formFiles {
+			if len(formFile.fileBytes) > 0 && formFile.fileName != "" {
+				w.Boundary()
+				part, err := w.CreateFormFile(formFile.formFileName, filepath.Base(formFile.fileName))
+				if err != nil {
+						return nil, err
+				}
+				_, err = part.Write(formFile.fileBytes)
+				if err != nil {
+						return nil, err
+				}
+			}
+		}
+
+		// Set the Boundary in the Content-Type
+		headerParams["Content-Type"] = w.FormDataContentType()
+
+		// Set Content-Length
+		headerParams["Content-Length"] = fmt.Sprintf("%d", body.Len())
+		w.Close()
+	}
+
+	if strings.HasPrefix(headerParams["Content-Type"], "application/x-www-form-urlencoded") && len(formParams) > 0 {
+		if body != nil {
+			return nil, errors.New("Cannot specify postBody and x-www-form-urlencoded form at the same time.")
+		}
+		body = &bytes.Buffer{}
+		body.WriteString(formParams.Encode())
+		// Set Content-Length
+		headerParams["Content-Length"] = fmt.Sprintf("%d", body.Len())
+	}
+
+	// Setup path and query parameters
+	url, err := url.Parse(path)
+	if err != nil {
+		return nil, err
+	}
+
+	// Override request host, if applicable
+	if c.cfg.Host != "" {
+		url.Host = c.cfg.Host
+	}
+
+	// Override request scheme, if applicable
+	if c.cfg.Scheme != "" {
+		url.Scheme = c.cfg.Scheme
+	}
+
+	// Adding Query Param
+	query := url.Query()
+	for k, v := range queryParams {
+		for _, iv := range v {
+			query.Add(k, iv)
+		}
+	}
+
+	// Encode the parameters.
+	url.RawQuery = query.Encode()
+
+	// Generate a new request
+	if body != nil {
+		localVarRequest, err = http.NewRequest(method, url.String(), body)
+	} else {
+		localVarRequest, err = http.NewRequest(method, url.String(), nil)
+	}
+	if err != nil {
+		return nil, err
+	}
+
+	// add header parameters, if any
+	if len(headerParams) > 0 {
+		headers := http.Header{}
+		for h, v := range headerParams {
+			headers.Set(h, v)
+		}
+		localVarRequest.Header = headers
+	}
+
+	// Add the user agent to the request.
+	localVarRequest.Header.Add("User-Agent", c.cfg.UserAgent)
+
+	if ctx != nil {
+		// add context to the request
+		localVarRequest = localVarRequest.WithContext(ctx)
+
+		// Walk through any authentication.
+
+		// OAuth2 authentication
+		if tok, ok := ctx.Value(ContextOAuth2).(oauth2.TokenSource); ok {
+			// We were able to grab an oauth2 token from the context
+			var latestToken *oauth2.Token
+			if latestToken, err = tok.Token(); err != nil {
+				return nil, err
+			}
+
+			latestToken.SetAuthHeader(localVarRequest)
+		}
+
+		// Basic HTTP Authentication
+		if auth, ok := ctx.Value(ContextBasicAuth).(BasicAuth); ok {
+			localVarRequest.SetBasicAuth(auth.UserName, auth.Password)
+		}
+
+		// AccessToken Authentication
+		if auth, ok := ctx.Value(ContextAccessToken).(string); ok {
+			localVarRequest.Header.Add("Authorization", "Bearer "+auth)
+		}
+
+	}
+
+	for header, value := range c.cfg.DefaultHeader {
+		localVarRequest.Header.Add(header, value)
+	}
+	return localVarRequest, nil
+}
+
+func (c *APIClient) decode(v interface{}, b []byte, contentType string) (err error) {
+	if len(b) == 0 {
+		return nil
+	}
+	if s, ok := v.(*string); ok {
+		*s = string(b)
+		return nil
+	}
+	if f, ok := v.(**os.File); ok {
+		*f, err = ioutil.TempFile("", "HttpClientFile")
+		if err != nil {
+			return
+		}
+		_, err = (*f).Write(b)
+		if err != nil {
+			return
+		}
+		_, err = (*f).Seek(0, io.SeekStart)
+		return
+	}
+	if xmlCheck.MatchString(contentType) {
+		if err = xml.Unmarshal(b, v); err != nil {
+			return err
+		}
+		return nil
+	}
+	if jsonCheck.MatchString(contentType) {
+		if actualObj, ok := v.(interface{ GetActualInstance() interface{} }); ok { // oneOf, anyOf schemas
+			if unmarshalObj, ok := actualObj.(interface{ UnmarshalJSON([]byte) error }); ok { // make sure it has UnmarshalJSON defined
+				if err = unmarshalObj.UnmarshalJSON(b); err != nil {
+					return err
+				}
+			} else {
+				return errors.New("Unknown type with GetActualInstance but no unmarshalObj.UnmarshalJSON defined")
+			}
+		} else if err = json.Unmarshal(b, v); err != nil { // simple model
+			return err
+		}
+		return nil
+	}
+	return errors.New("undefined response type")
+}
+
+// Add a file to the multipart request
+func addFile(w *multipart.Writer, fieldName, path string) error {
+	file, err := os.Open(path)
+	if err != nil {
+		return err
+	}
+	defer file.Close()
+
+	part, err := w.CreateFormFile(fieldName, filepath.Base(path))
+	if err != nil {
+		return err
+	}
+	_, err = io.Copy(part, file)
+
+	return err
+}
+
+// Prevent trying to import "fmt"
+func reportError(format string, a ...interface{}) error {
+	return fmt.Errorf(format, a...)
+}
+
+// Set request body from an interface{}
+func setBody(body interface{}, contentType string) (bodyBuf *bytes.Buffer, err error) {
+	if bodyBuf == nil {
+		bodyBuf = &bytes.Buffer{}
+	}
+
+	if reader, ok := body.(io.Reader); ok {
+		_, err = bodyBuf.ReadFrom(reader)
+	} else if fp, ok := body.(**os.File); ok {
+		_, err = bodyBuf.ReadFrom(*fp)
+	} else if b, ok := body.([]byte); ok {
+		_, err = bodyBuf.Write(b)
+	} else if s, ok := body.(string); ok {
+		_, err = bodyBuf.WriteString(s)
+	} else if s, ok := body.(*string); ok {
+		_, err = bodyBuf.WriteString(*s)
+	} else if jsonCheck.MatchString(contentType) {
+		err = json.NewEncoder(bodyBuf).Encode(body)
+	} else if xmlCheck.MatchString(contentType) {
+		err = xml.NewEncoder(bodyBuf).Encode(body)
+	}
+
+	if err != nil {
+		return nil, err
+	}
+
+	if bodyBuf.Len() == 0 {
+		err = fmt.Errorf("Invalid body type %s\n", contentType)
+		return nil, err
+	}
+	return bodyBuf, nil
+}
+
+// detectContentType method is used to figure out `Request.Body` content type for request header
+func detectContentType(body interface{}) string {
+	contentType := "text/plain; charset=utf-8"
+	kind := reflect.TypeOf(body).Kind()
+
+	switch kind {
+	case reflect.Struct, reflect.Map, reflect.Ptr:
+		contentType = "application/json; charset=utf-8"
+	case reflect.String:
+		contentType = "text/plain; charset=utf-8"
+	default:
+		if b, ok := body.([]byte); ok {
+			contentType = http.DetectContentType(b)
+		} else if kind == reflect.Slice {
+			contentType = "application/json; charset=utf-8"
+		}
+	}
+
+	return contentType
+}
+
+// Ripped from https://github.com/gregjones/httpcache/blob/master/httpcache.go
+type cacheControl map[string]string
+
+func parseCacheControl(headers http.Header) cacheControl {
+	cc := cacheControl{}
+	ccHeader := headers.Get("Cache-Control")
+	for _, part := range strings.Split(ccHeader, ",") {
+		part = strings.Trim(part, " ")
+		if part == "" {
+			continue
+		}
+		if strings.ContainsRune(part, '=') {
+			keyval := strings.Split(part, "=")
+			cc[strings.Trim(keyval[0], " ")] = strings.Trim(keyval[1], ",")
+		} else {
+			cc[part] = ""
+		}
+	}
+	return cc
+}
+
+// CacheExpires helper function to determine remaining time before repeating a request.
+func CacheExpires(r *http.Response) time.Time {
+	// Figure out when the cache expires.
+	var expires time.Time
+	now, err := time.Parse(time.RFC1123, r.Header.Get("date"))
+	if err != nil {
+		return time.Now()
+	}
+	respCacheControl := parseCacheControl(r.Header)
+
+	if maxAge, ok := respCacheControl["max-age"]; ok {
+		lifetime, err := time.ParseDuration(maxAge + "s")
+		if err != nil {
+			expires = now
+		} else {
+			expires = now.Add(lifetime)
+		}
+	} else {
+		expiresHeader := r.Header.Get("Expires")
+		if expiresHeader != "" {
+			expires, err = time.Parse(time.RFC1123, expiresHeader)
+			if err != nil {
+				expires = now
+			}
+		}
+	}
+	return expires
+}
+
+func strlen(s string) int {
+	return utf8.RuneCountInString(s)
+}
+
+// GenericOpenAPIError Provides access to the body, error and model on returned errors.
+type GenericOpenAPIError struct {
+	body  []byte
+	error string
+	model interface{}
+}
+
+// Error returns non-empty string if there was an error.
+func (e GenericOpenAPIError) Error() string {
+	return e.error
+}
+
+// Body returns the raw bytes of the response
+func (e GenericOpenAPIError) Body() []byte {
+	return e.body
+}
+
+// Model returns the unpacked model of the error
+func (e GenericOpenAPIError) Model() interface{} {
+	return e.model
+}

samples/openapi3/client/features/mulitple-data-in-forms/configuration.go

@@ -0,0 +1,230 @@
+/*
+Multiple Files via form-data
+
+This is a sample server with a single endpoint that accepts two files via a multipart/form-data POST request.
+
+API version: 1.0.0
+*/
+
+// Code generated by OpenAPI Generator (https://openapi-generator.tech); DO NOT EDIT.
+
+package openapi
+
+import (
+	"context"
+	"fmt"
+	"net/http"
+	"strings"
+)
+
+// contextKeys are used to identify the type of value in the context.
+// Since these are string, it is possible to get a short description of the
+// context key for logging and debugging using key.String().
+
+type contextKey string
+
+func (c contextKey) String() string {
+	return "auth " + string(c)
+}
+
+var (
+	// ContextOAuth2 takes an oauth2.TokenSource as authentication for the request.
+	ContextOAuth2 = contextKey("token")
+
+	// ContextBasicAuth takes BasicAuth as authentication for the request.
+	ContextBasicAuth = contextKey("basic")
+
+	// ContextAccessToken takes a string oauth2 access token as authentication for the request.
+	ContextAccessToken = contextKey("accesstoken")
+
+	// ContextAPIKeys takes a string apikey as authentication for the request
+	ContextAPIKeys = contextKey("apiKeys")
+
+	// ContextHttpSignatureAuth takes HttpSignatureAuth as authentication for the request.
+	ContextHttpSignatureAuth = contextKey("httpsignature")
+
+	// ContextServerIndex uses a server configuration from the index.
+	ContextServerIndex = contextKey("serverIndex")
+
+	// ContextOperationServerIndices uses a server configuration from the index mapping.
+	ContextOperationServerIndices = contextKey("serverOperationIndices")
+
+	// ContextServerVariables overrides a server configuration variables.
+	ContextServerVariables = contextKey("serverVariables")
+
+	// ContextOperationServerVariables overrides a server configuration variables using operation specific values.
+	ContextOperationServerVariables = contextKey("serverOperationVariables")
+)
+
+// BasicAuth provides basic http authentication to a request passed via context using ContextBasicAuth
+type BasicAuth struct {
+	UserName string `json:"userName,omitempty"`
+	Password string `json:"password,omitempty"`
+}
+
+// APIKey provides API key based authentication to a request passed via context using ContextAPIKey
+type APIKey struct {
+	Key    string
+	Prefix string
+}
+
+// ServerVariable stores the information about a server variable
+type ServerVariable struct {
+	Description  string
+	DefaultValue string
+	EnumValues   []string
+}
+
+// ServerConfiguration stores the information about a server
+type ServerConfiguration struct {
+	URL string
+	Description string
+	Variables map[string]ServerVariable
+}
+
+// ServerConfigurations stores multiple ServerConfiguration items
+type ServerConfigurations []ServerConfiguration
+
+// Configuration stores the configuration of the API client
+type Configuration struct {
+	Host             string            `json:"host,omitempty"`
+	Scheme           string            `json:"scheme,omitempty"`
+	DefaultHeader    map[string]string `json:"defaultHeader,omitempty"`
+	UserAgent        string            `json:"userAgent,omitempty"`
+	Debug            bool              `json:"debug,omitempty"`
+	Servers          ServerConfigurations
+	OperationServers map[string]ServerConfigurations
+	HTTPClient       *http.Client
+}
+
+// NewConfiguration returns a new Configuration object
+func NewConfiguration() *Configuration {
+	cfg := &Configuration{
+		DefaultHeader:    make(map[string]string),
+		UserAgent:        "OpenAPI-Generator/1.0.0/go",
+		Debug:            false,
+		Servers:          ServerConfigurations{
+			{
+				URL: "http://example.com",
+				Description: "No description provided",
+			},
+		},
+		OperationServers: map[string]ServerConfigurations{
+		},
+	}
+	return cfg
+}
+
+// AddDefaultHeader adds a new HTTP header to the default header in the request
+func (c *Configuration) AddDefaultHeader(key string, value string) {
+	c.DefaultHeader[key] = value
+}
+
+// URL formats template on a index using given variables
+func (sc ServerConfigurations) URL(index int, variables map[string]string) (string, error) {
+	if index < 0 || len(sc) <= index {
+		return "", fmt.Errorf("Index %v out of range %v", index, len(sc)-1)
+	}
+	server := sc[index]
+	url := server.URL
+
+	// go through variables and replace placeholders
+	for name, variable := range server.Variables {
+		if value, ok := variables[name]; ok {
+			found := bool(len(variable.EnumValues) == 0)
+			for _, enumValue := range variable.EnumValues {
+				if value == enumValue {
+					found = true
+				}
+			}
+			if !found {
+				return "", fmt.Errorf("The variable %s in the server URL has invalid value %v. Must be %v", name, value, variable.EnumValues)
+			}
+			url = strings.Replace(url, "{"+name+"}", value, -1)
+		} else {
+			url = strings.Replace(url, "{"+name+"}", variable.DefaultValue, -1)
+		}
+	}
+	return url, nil
+}
+
+// ServerURL returns URL based on server settings
+func (c *Configuration) ServerURL(index int, variables map[string]string) (string, error) {
+	return c.Servers.URL(index, variables)
+}
+
+func getServerIndex(ctx context.Context) (int, error) {
+	si := ctx.Value(ContextServerIndex)
+	if si != nil {
+		if index, ok := si.(int); ok {
+			return index, nil
+		}
+		return 0, reportError("Invalid type %T should be int", si)
+	}
+	return 0, nil
+}
+
+func getServerOperationIndex(ctx context.Context, endpoint string) (int, error) {
+	osi := ctx.Value(ContextOperationServerIndices)
+	if osi != nil {
+		if operationIndices, ok := osi.(map[string]int); !ok {
+			return 0, reportError("Invalid type %T should be map[string]int", osi)
+		} else {
+			index, ok := operationIndices[endpoint]
+			if ok {
+				return index, nil
+			}
+		}
+	}
+	return getServerIndex(ctx)
+}
+
+func getServerVariables(ctx context.Context) (map[string]string, error) {
+	sv := ctx.Value(ContextServerVariables)
+	if sv != nil {
+		if variables, ok := sv.(map[string]string); ok {
+			return variables, nil
+		}
+		return nil, reportError("ctx value of ContextServerVariables has invalid type %T should be map[string]string", sv)
+	}
+	return nil, nil
+}
+
+func getServerOperationVariables(ctx context.Context, endpoint string) (map[string]string, error) {
+	osv := ctx.Value(ContextOperationServerVariables)
+	if osv != nil {
+		if operationVariables, ok := osv.(map[string]map[string]string); !ok {
+			return nil, reportError("ctx value of ContextOperationServerVariables has invalid type %T should be map[string]map[string]string", osv)
+		} else {
+			variables, ok := operationVariables[endpoint]
+			if ok {
+				return variables, nil
+			}
+		}
+	}
+	return getServerVariables(ctx)
+}
+
+// ServerURLWithContext returns a new server URL given an endpoint
+func (c *Configuration) ServerURLWithContext(ctx context.Context, endpoint string) (string, error) {
+	sc, ok := c.OperationServers[endpoint]
+	if !ok {
+		sc = c.Servers
+	}
+
+	if ctx == nil {
+		return sc.URL(0, nil)
+	}
+
+	index, err := getServerOperationIndex(ctx, endpoint)
+	if err != nil {
+		return "", err
+	}
+
+	variables, err := getServerOperationVariables(ctx, endpoint)
+	if err != nil {
+		return "", err
+	}
+
+	return sc.URL(index, variables)
+}

samples/openapi3/client/features/mulitple-data-in-forms/docs/ApiResponse.md

@@ -0,0 +1,108 @@
+# ApiResponse
+
+## Properties
+
+Name | Type | Description | Notes
+------------ | ------------- | ------------- | -------------
+**Code** | Pointer to **int32** |  | [optional] 
+**Type** | Pointer to **string** |  | [optional] 
+**Message** | Pointer to **string** |  | [optional] 
+
+## Methods
+
+### NewApiResponse
+
+`func NewApiResponse() *ApiResponse`
+
+NewApiResponse instantiates a new ApiResponse object
+This constructor will assign default values to properties that have it defined,
+and makes sure properties required by API are set, but the set of arguments
+will change when the set of required properties is changed
+
+### NewApiResponseWithDefaults
+
+`func NewApiResponseWithDefaults() *ApiResponse`
+
+NewApiResponseWithDefaults instantiates a new ApiResponse object
+This constructor will only assign default values to properties that have it defined,
+but it doesn't guarantee that properties required by API are set
+
+### GetCode
+
+`func (o *ApiResponse) GetCode() int32`
+
+GetCode returns the Code field if non-nil, zero value otherwise.
+
+### GetCodeOk
+
+`func (o *ApiResponse) GetCodeOk() (*int32, bool)`
+
+GetCodeOk returns a tuple with the Code field if it's non-nil, zero value otherwise
+and a boolean to check if the value has been set.
+
+### SetCode
+
+`func (o *ApiResponse) SetCode(v int32)`
+
+SetCode sets Code field to given value.
+
+### HasCode
+
+`func (o *ApiResponse) HasCode() bool`
+
+HasCode returns a boolean if a field has been set.
+
+### GetType
+
+`func (o *ApiResponse) GetType() string`
+
+GetType returns the Type field if non-nil, zero value otherwise.
+
+### GetTypeOk
+
+`func (o *ApiResponse) GetTypeOk() (*string, bool)`
+
+GetTypeOk returns a tuple with the Type field if it's non-nil, zero value otherwise
+and a boolean to check if the value has been set.
+
+### SetType
+
+`func (o *ApiResponse) SetType(v string)`
+
+SetType sets Type field to given value.
+
+### HasType
+
+`func (o *ApiResponse) HasType() bool`
+
+HasType returns a boolean if a field has been set.
+
+### GetMessage
+
+`func (o *ApiResponse) GetMessage() string`
+
+GetMessage returns the Message field if non-nil, zero value otherwise.
+
+### GetMessageOk
+
+`func (o *ApiResponse) GetMessageOk() (*string, bool)`
+
+GetMessageOk returns a tuple with the Message field if it's non-nil, zero value otherwise
+and a boolean to check if the value has been set.
+
+### SetMessage
+
+`func (o *ApiResponse) SetMessage(v string)`
+
+SetMessage sets Message field to given value.
+
+### HasMessage
+
+`func (o *ApiResponse) HasMessage() bool`
+
+HasMessage returns a boolean if a field has been set.
+
+
+[[Back to Model list]](../README.md#documentation-for-models) [[Back to API list]](../README.md#documentation-for-api-endpoints) [[Back to README]](../README.md)
+
+

samples/openapi3/client/features/mulitple-data-in-forms/docs/DefaultApi.md

@@ -0,0 +1,75 @@
+# \DefaultApi
+
+All URIs are relative to *http://example.com*
+
+Method | HTTP request | Description
+------------- | ------------- | -------------
+[**UploadFiles**](DefaultApi.md#UploadFiles) | **Post** /uploadFiles | uploads two files
+
+
+
+## UploadFiles
+
+> ApiResponse UploadFiles(ctx).File(file).SecondFile(secondFile).Execute()
+
+uploads two files
+
+### Example
+
+```go
+package main
+
+import (
+    "context"
+    "fmt"
+    "os"
+    openapiclient "./openapi"
+)
+
+func main() {
+    file := os.NewFile(1234, "some_file") // *os.File | file to upload (optional)
+    secondFile := os.NewFile(1234, "some_file") // *os.File | another file to upload (optional)
+
+    configuration := openapiclient.NewConfiguration()
+    api_client := openapiclient.NewAPIClient(configuration)
+    resp, r, err := api_client.DefaultApi.UploadFiles(context.Background()).File(file).SecondFile(secondFile).Execute()
+    if err != nil {
+        fmt.Fprintf(os.Stderr, "Error when calling `DefaultApi.UploadFiles``: %v\n", err)
+        fmt.Fprintf(os.Stderr, "Full HTTP response: %v\n", r)
+    }
+    // response from `UploadFiles`: ApiResponse
+    fmt.Fprintf(os.Stdout, "Response from `DefaultApi.UploadFiles`: %v\n", resp)
+}
+```
+
+### Path Parameters
+
+
+
+### Other Parameters
+
+Other parameters are passed through a pointer to a apiUploadFilesRequest struct via the builder pattern
+
+
+Name | Type | Description  | Notes
+------------- | ------------- | ------------- | -------------
+ **file** | ***os.File** | file to upload | 
+ **secondFile** | ***os.File** | another file to upload | 
+
+### Return type
+
+[**ApiResponse**](ApiResponse.md)
+
+### Authorization
+
+No authorization required
+
+### HTTP request headers
+
+- **Content-Type**: multipart/form-data
+- **Accept**: application/json
+
+[[Back to top]](#) [[Back to API list]](../README.md#documentation-for-api-endpoints)
+[[Back to Model list]](../README.md#documentation-for-models)
+[[Back to README]](../README.md)
+

samples/openapi3/client/features/mulitple-data-in-forms/git_push.sh

@@ -0,0 +1,57 @@
+#!/bin/sh
+# ref: https://help.github.com/articles/adding-an-existing-project-to-github-using-the-command-line/
+#
+# Usage example: /bin/sh ./git_push.sh wing328 openapi-petstore-perl "minor update" "gitlab.com"
+
+git_user_id=$1
+git_repo_id=$2
+release_note=$3
+git_host=$4
+
+if [ "$git_host" = "" ]; then
+    git_host="github.com"
+    echo "[INFO] No command line input provided. Set \$git_host to $git_host"
+fi
+
+if [ "$git_user_id" = "" ]; then
+    git_user_id="GIT_USER_ID"
+    echo "[INFO] No command line input provided. Set \$git_user_id to $git_user_id"
+fi
+
+if [ "$git_repo_id" = "" ]; then
+    git_repo_id="GIT_REPO_ID"
+    echo "[INFO] No command line input provided. Set \$git_repo_id to $git_repo_id"
+fi
+
+if [ "$release_note" = "" ]; then
+    release_note="Minor update"
+    echo "[INFO] No command line input provided. Set \$release_note to $release_note"
+fi
+
+# Initialize the local directory as a Git repository
+git init
+
+# Adds the files in the local repository and stages them for commit.
+git add .
+
+# Commits the tracked changes and prepares them to be pushed to a remote repository.
+git commit -m "$release_note"
+
+# Sets the new remote
+git_remote=$(git remote)
+if [ "$git_remote" = "" ]; then # git remote not defined
+
+    if [ "$GIT_TOKEN" = "" ]; then
+        echo "[INFO] \$GIT_TOKEN (environment variable) is not set. Using the git credential in your environment."
+        git remote add origin https://${git_host}/${git_user_id}/${git_repo_id}.git
+    else
+        git remote add origin https://${git_user_id}:"${GIT_TOKEN}"@${git_host}/${git_user_id}/${git_repo_id}.git
+    fi
+
+fi
+
+git pull origin master
+
+# Pushes (Forces) the changes in the local repository up to the remote repository
+echo "Git pushing to https://${git_host}/${git_user_id}/${git_repo_id}.git"
+git push origin master 2>&1 | grep -v 'To https'

samples/openapi3/client/features/mulitple-data-in-forms/go.mod

@@ -0,0 +1,7 @@
+module github.com/GIT_USER_ID/GIT_REPO_ID
+
+go 1.13
+
+require (
+	golang.org/x/oauth2 v0.0.0-20210218202405-ba52d332ba99
+)

samples/openapi3/client/features/mulitple-data-in-forms/go.sum

@@ -0,0 +1,13 @@
+cloud.google.com/go v0.34.0/go.mod h1:aQUYkXzVsufM+DwF1aE+0xfcU+56JwCaLick0ClmMTw=
+github.com/golang/protobuf v1.2.0 h1:P3YflyNX/ehuJFLhxviNdFxQPkGK5cDcApsge1SqnvM=
+github.com/golang/protobuf v1.2.0/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
+golang.org/x/net v0.0.0-20180724234803-3673e40ba225/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
+golang.org/x/net v0.0.0-20190108225652-1e06a53dbb7e h1:bRhVy7zSSasaqNksaRZiA5EEI+Ei4I1nO5Jh72wfHlg=
+golang.org/x/net v0.0.0-20190108225652-1e06a53dbb7e/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
+golang.org/x/oauth2 v0.0.0-20190604053449-0f29369cfe45 h1:SVwTIAaPC2U/AvvLNZ2a7OVsmBpC8L5BlwK1whH3hm0=
+golang.org/x/oauth2 v0.0.0-20190604053449-0f29369cfe45/go.mod h1:gOpvHmFTYa4IltrdGE7lF6nIHvwfUNPOp7c8zoXwtLw=
+golang.org/x/sync v0.0.0-20181221193216-37e7f081c4d4 h1:YUO/7uOKsKeq9UokNS62b8FYywz3ker1l1vDZRCRefw=
+golang.org/x/sync v0.0.0-20181221193216-37e7f081c4d4/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
+google.golang.org/appengine v1.4.0 h1:/wp5JvzpHIxhs/dumFmF7BXTf3Z+dd4uXta4kVyO508=
+google.golang.org/appengine v1.4.0/go.mod h1:xpcJRLb0r/rnEns0DIKYYv+WjYCduHsrkT7/EB5XEv4=

samples/openapi3/client/features/mulitple-data-in-forms/model_api_response.go

@@ -0,0 +1,187 @@
+/*
+Multiple Files via form-data
+
+This is a sample server with a single endpoint that accepts two files via a multipart/form-data POST request.
+
+API version: 1.0.0
+*/
+
+// Code generated by OpenAPI Generator (https://openapi-generator.tech); DO NOT EDIT.
+
+package openapi
+
+import (
+	"encoding/json"
+)
+
+// ApiResponse Describes the result of uploading files
+type ApiResponse struct {
+	Code *int32 `json:"code,omitempty"`
+	Type *string `json:"type,omitempty"`
+	Message *string `json:"message,omitempty"`
+}
+
+// NewApiResponse instantiates a new ApiResponse object
+// This constructor will assign default values to properties that have it defined,
+// and makes sure properties required by API are set, but the set of arguments
+// will change when the set of required properties is changed
+func NewApiResponse() *ApiResponse {
+	this := ApiResponse{}
+	return &this
+}
+
+// NewApiResponseWithDefaults instantiates a new ApiResponse object
+// This constructor will only assign default values to properties that have it defined,
+// but it doesn't guarantee that properties required by API are set
+func NewApiResponseWithDefaults() *ApiResponse {
+	this := ApiResponse{}
+	return &this
+}
+
+// GetCode returns the Code field value if set, zero value otherwise.
+func (o *ApiResponse) GetCode() int32 {
+	if o == nil || o.Code == nil {
+		var ret int32
+		return ret
+	}
+	return *o.Code
+}
+
+// GetCodeOk returns a tuple with the Code field value if set, nil otherwise
+// and a boolean to check if the value has been set.
+func (o *ApiResponse) GetCodeOk() (*int32, bool) {
+	if o == nil || o.Code == nil {
+		return nil, false
+	}
+	return o.Code, true
+}
+
+// HasCode returns a boolean if a field has been set.
+func (o *ApiResponse) HasCode() bool {
+	if o != nil && o.Code != nil {
+		return true
+	}
+
+	return false
+}
+
+// SetCode gets a reference to the given int32 and assigns it to the Code field.
+func (o *ApiResponse) SetCode(v int32) {
+	o.Code = &v
+}
+
+// GetType returns the Type field value if set, zero value otherwise.
+func (o *ApiResponse) GetType() string {
+	if o == nil || o.Type == nil {
+		var ret string
+		return ret
+	}
+	return *o.Type
+}
+
+// GetTypeOk returns a tuple with the Type field value if set, nil otherwise
+// and a boolean to check if the value has been set.
+func (o *ApiResponse) GetTypeOk() (*string, bool) {
+	if o == nil || o.Type == nil {
+		return nil, false
+	}
+	return o.Type, true
+}
+
+// HasType returns a boolean if a field has been set.
+func (o *ApiResponse) HasType() bool {
+	if o != nil && o.Type != nil {
+		return true
+	}
+
+	return false
+}
+
+// SetType gets a reference to the given string and assigns it to the Type field.
+func (o *ApiResponse) SetType(v string) {
+	o.Type = &v
+}
+
+// GetMessage returns the Message field value if set, zero value otherwise.
+func (o *ApiResponse) GetMessage() string {
+	if o == nil || o.Message == nil {
+		var ret string
+		return ret
+	}
+	return *o.Message
+}
+
+// GetMessageOk returns a tuple with the Message field value if set, nil otherwise
+// and a boolean to check if the value has been set.
+func (o *ApiResponse) GetMessageOk() (*string, bool) {
+	if o == nil || o.Message == nil {
+		return nil, false
+	}
+	return o.Message, true
+}
+
+// HasMessage returns a boolean if a field has been set.
+func (o *ApiResponse) HasMessage() bool {
+	if o != nil && o.Message != nil {
+		return true
+	}
+
+	return false
+}
+
+// SetMessage gets a reference to the given string and assigns it to the Message field.
+func (o *ApiResponse) SetMessage(v string) {
+	o.Message = &v
+}
+
+func (o ApiResponse) MarshalJSON() ([]byte, error) {
+	toSerialize := map[string]interface{}{}
+	if o.Code != nil {
+		toSerialize["code"] = o.Code
+	}
+	if o.Type != nil {
+		toSerialize["type"] = o.Type
+	}
+	if o.Message != nil {
+		toSerialize["message"] = o.Message
+	}
+	return json.Marshal(toSerialize)
+}
+
+type NullableApiResponse struct {
+	value *ApiResponse
+	isSet bool
+}
+
+func (v NullableApiResponse) Get() *ApiResponse {
+	return v.value
+}
+
+func (v *NullableApiResponse) Set(val *ApiResponse) {
+	v.value = val
+	v.isSet = true
+}
+
+func (v NullableApiResponse) IsSet() bool {
+	return v.isSet
+}
+
+func (v *NullableApiResponse) Unset() {
+	v.value = nil
+	v.isSet = false
+}
+
+func NewNullableApiResponse(val *ApiResponse) *NullableApiResponse {
+	return &NullableApiResponse{value: val, isSet: true}
+}
+
+func (v NullableApiResponse) MarshalJSON() ([]byte, error) {
+	return json.Marshal(v.value)
+}
+
+func (v *NullableApiResponse) UnmarshalJSON(src []byte) error {
+	v.isSet = true
+	return json.Unmarshal(src, &v.value)
+}
+
+

samples/openapi3/client/features/mulitple-data-in-forms/multiple-files-forms.yaml

@@ -0,0 +1,52 @@
+openapi: 3.0.0
+servers:
+  - url: "http://example.com"
+info:
+  description: >-
+    This is a sample server with a single endpoint that accepts two files via a multipart/form-data POST request.
+  version: 1.0.0
+  title: Multiple Files via form-data
+  license:
+    name: Apache-2.0
+    url: "https://www.apache.org/licenses/LICENSE-2.0.html"
+paths:
+  "/uploadFiles":
+    post:
+      summary: uploads two files
+      description: ""
+      operationId: uploadFiles
+      responses:
+        "200":
+          description: successful operation
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/ApiResponse"
+      requestBody:
+        content:
+          multipart/form-data:
+            schema:
+              type: object
+              properties:
+                file:
+                  description: file to upload
+                  type: string
+                  format: binary
+                secondFile:
+                  description: another file to upload
+                  type: string
+                  format: binary
+components:
+  schemas:
+    ApiResponse:
+      title: An uploaded response
+      description: Describes the result of uploading files
+      type: object
+      properties:
+        code:
+          type: integer
+          format: int32
+        type:
+          type: string
+        message:
+          type: string

samples/openapi3/client/features/mulitple-data-in-forms/response.go

@@ -0,0 +1,47 @@
+/*
+Multiple Files via form-data
+
+This is a sample server with a single endpoint that accepts two files via a multipart/form-data POST request.
+
+API version: 1.0.0
+*/
+
+// Code generated by OpenAPI Generator (https://openapi-generator.tech); DO NOT EDIT.
+
+package openapi
+
+import (
+	"net/http"
+)
+
+// APIResponse stores the API response returned by the server.
+type APIResponse struct {
+	*http.Response `json:"-"`
+	Message        string `json:"message,omitempty"`
+	// Operation is the name of the OpenAPI operation.
+	Operation string `json:"operation,omitempty"`
+	// RequestURL is the request URL. This value is always available, even if the
+	// embedded *http.Response is nil.
+	RequestURL string `json:"url,omitempty"`
+	// Method is the HTTP method used for the request.  This value is always
+	// available, even if the embedded *http.Response is nil.
+	Method string `json:"method,omitempty"`
+	// Payload holds the contents of the response body (which may be nil or empty).
+	// This is provided here as the raw response.Body() reader will have already
+	// been drained.
+	Payload []byte `json:"-"`
+}
+
+// NewAPIResponse returns a new APIResponse object.
+func NewAPIResponse(r *http.Response) *APIResponse {
+
+	response := &APIResponse{Response: r}
+	return response
+}
+
+// NewAPIResponseWithError returns a new APIResponse object with the provided error message.
+func NewAPIResponseWithError(errorMessage string) *APIResponse {
+
+	response := &APIResponse{Message: errorMessage}
+	return response
+}

samples/openapi3/client/features/mulitple-data-in-forms/utils.go

@@ -0,0 +1,328 @@
+/*
+Multiple Files via form-data
+
+This is a sample server with a single endpoint that accepts two files via a multipart/form-data POST request.
+
+API version: 1.0.0
+*/
+
+// Code generated by OpenAPI Generator (https://openapi-generator.tech); DO NOT EDIT.
+
+package openapi
+
+import (
+	"encoding/json"
+	"time"
+)
+
+// PtrBool is a helper routine that returns a pointer to given boolean value.
+func PtrBool(v bool) *bool { return &v }
+
+// PtrInt is a helper routine that returns a pointer to given integer value.
+func PtrInt(v int) *int { return &v }
+
+// PtrInt32 is a helper routine that returns a pointer to given integer value.
+func PtrInt32(v int32) *int32 { return &v }
+
+// PtrInt64 is a helper routine that returns a pointer to given integer value.
+func PtrInt64(v int64) *int64 { return &v }
+
+// PtrFloat32 is a helper routine that returns a pointer to given float value.
+func PtrFloat32(v float32) *float32 { return &v }
+
+// PtrFloat64 is a helper routine that returns a pointer to given float value.
+func PtrFloat64(v float64) *float64 { return &v }
+
+// PtrString is a helper routine that returns a pointer to given string value.
+func PtrString(v string) *string { return &v }
+
+// PtrTime is helper routine that returns a pointer to given Time value.
+func PtrTime(v time.Time) *time.Time { return &v }
+
+type NullableBool struct {
+	value *bool
+	isSet bool
+}
+
+func (v NullableBool) Get() *bool {
+	return v.value
+}
+
+func (v *NullableBool) Set(val *bool) {
+	v.value = val
+	v.isSet = true
+}
+
+func (v NullableBool) IsSet() bool {
+	return v.isSet
+}
+
+func (v *NullableBool) Unset() {
+	v.value = nil
+	v.isSet = false
+}
+
+func NewNullableBool(val *bool) *NullableBool {
+	return &NullableBool{value: val, isSet: true}
+}
+
+func (v NullableBool) MarshalJSON() ([]byte, error) {
+	return json.Marshal(v.value)
+}
+
+func (v *NullableBool) UnmarshalJSON(src []byte) error {
+	v.isSet = true
+	return json.Unmarshal(src, &v.value)
+}
+
+type NullableInt struct {
+	value *int
+	isSet bool
+}
+
+func (v NullableInt) Get() *int {
+	return v.value
+}
+
+func (v *NullableInt) Set(val *int) {
+	v.value = val
+	v.isSet = true
+}
+
+func (v NullableInt) IsSet() bool {
+	return v.isSet
+}
+
+func (v *NullableInt) Unset() {
+	v.value = nil
+	v.isSet = false
+}
+
+func NewNullableInt(val *int) *NullableInt {
+	return &NullableInt{value: val, isSet: true}
+}
+
+func (v NullableInt) MarshalJSON() ([]byte, error) {
+	return json.Marshal(v.value)
+}
+
+func (v *NullableInt) UnmarshalJSON(src []byte) error {
+	v.isSet = true
+	return json.Unmarshal(src, &v.value)
+}
+
+type NullableInt32 struct {
+	value *int32
+	isSet bool
+}
+
+func (v NullableInt32) Get() *int32 {
+	return v.value
+}
+
+func (v *NullableInt32) Set(val *int32) {
+	v.value = val
+	v.isSet = true
+}
+
+func (v NullableInt32) IsSet() bool {
+	return v.isSet
+}
+
+func (v *NullableInt32) Unset() {
+	v.value = nil
+	v.isSet = false
+}
+
+func NewNullableInt32(val *int32) *NullableInt32 {
+	return &NullableInt32{value: val, isSet: true}
+}
+
+func (v NullableInt32) MarshalJSON() ([]byte, error) {
+	return json.Marshal(v.value)
+}
+
+func (v *NullableInt32) UnmarshalJSON(src []byte) error {
+	v.isSet = true
+	return json.Unmarshal(src, &v.value)
+}
+
+type NullableInt64 struct {
+	value *int64
+	isSet bool
+}
+
+func (v NullableInt64) Get() *int64 {
+	return v.value
+}
+
+func (v *NullableInt64) Set(val *int64) {
+	v.value = val
+	v.isSet = true
+}
+
+func (v NullableInt64) IsSet() bool {
+	return v.isSet
+}
+
+func (v *NullableInt64) Unset() {
+	v.value = nil
+	v.isSet = false
+}
+
+func NewNullableInt64(val *int64) *NullableInt64 {
+	return &NullableInt64{value: val, isSet: true}
+}
+
+func (v NullableInt64) MarshalJSON() ([]byte, error) {
+	return json.Marshal(v.value)
+}
+
+func (v *NullableInt64) UnmarshalJSON(src []byte) error {
+	v.isSet = true
+	return json.Unmarshal(src, &v.value)
+}
+
+type NullableFloat32 struct {
+	value *float32
+	isSet bool
+}
+
+func (v NullableFloat32) Get() *float32 {
+	return v.value
+}
+
+func (v *NullableFloat32) Set(val *float32) {
+	v.value = val
+	v.isSet = true
+}
+
+func (v NullableFloat32) IsSet() bool {
+	return v.isSet
+}
+
+func (v *NullableFloat32) Unset() {
+	v.value = nil
+	v.isSet = false
+}
+
+func NewNullableFloat32(val *float32) *NullableFloat32 {
+	return &NullableFloat32{value: val, isSet: true}
+}
+
+func (v NullableFloat32) MarshalJSON() ([]byte, error) {
+	return json.Marshal(v.value)
+}
+
+func (v *NullableFloat32) UnmarshalJSON(src []byte) error {
+	v.isSet = true
+	return json.Unmarshal(src, &v.value)
+}
+
+type NullableFloat64 struct {
+	value *float64
+	isSet bool
+}
+
+func (v NullableFloat64) Get() *float64 {
+	return v.value
+}
+
+func (v *NullableFloat64) Set(val *float64) {
+	v.value = val
+	v.isSet = true
+}
+
+func (v NullableFloat64) IsSet() bool {
+	return v.isSet
+}
+
+func (v *NullableFloat64) Unset() {
+	v.value = nil
+	v.isSet = false
+}
+
+func NewNullableFloat64(val *float64) *NullableFloat64 {
+	return &NullableFloat64{value: val, isSet: true}
+}
+
+func (v NullableFloat64) MarshalJSON() ([]byte, error) {
+	return json.Marshal(v.value)
+}
+
+func (v *NullableFloat64) UnmarshalJSON(src []byte) error {
+	v.isSet = true
+	return json.Unmarshal(src, &v.value)
+}
+
+type NullableString struct {
+	value *string
+	isSet bool
+}
+
+func (v NullableString) Get() *string {
+	return v.value
+}
+
+func (v *NullableString) Set(val *string) {
+	v.value = val
+	v.isSet = true
+}
+
+func (v NullableString) IsSet() bool {
+	return v.isSet
+}
+
+func (v *NullableString) Unset() {
+	v.value = nil
+	v.isSet = false
+}
+
+func NewNullableString(val *string) *NullableString {
+	return &NullableString{value: val, isSet: true}
+}
+
+func (v NullableString) MarshalJSON() ([]byte, error) {
+	return json.Marshal(v.value)
+}
+
+func (v *NullableString) UnmarshalJSON(src []byte) error {
+	v.isSet = true
+	return json.Unmarshal(src, &v.value)
+}
+
+type NullableTime struct {
+	value *time.Time
+	isSet bool
+}
+
+func (v NullableTime) Get() *time.Time {
+	return v.value
+}
+
+func (v *NullableTime) Set(val *time.Time) {
+	v.value = val
+	v.isSet = true
+}
+
+func (v NullableTime) IsSet() bool {
+	return v.isSet
+}
+
+func (v *NullableTime) Unset() {
+	v.value = nil
+	v.isSet = false
+}
+
+func NewNullableTime(val *time.Time) *NullableTime {
+	return &NullableTime{value: val, isSet: true}
+}
+
+func (v NullableTime) MarshalJSON() ([]byte, error) {
+	return v.value.MarshalJSON()
+}
+
+func (v *NullableTime) UnmarshalJSON(src []byte) error {
+	v.isSet = true
+	return json.Unmarshal(src, &v.value)
+}

samples/openapi3/client/petstore/go/go-petstore/api_another_fake.go

@@ -80,9 +80,7 @@ func (a *AnotherFakeApiService) Call123TestSpecialTagsExecute(r ApiCall123TestSp
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPatch
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  Client
 	)
 
@@ -119,7 +117,7 @@ func (a *AnotherFakeApiService) Call123TestSpecialTagsExecute(r ApiCall123TestSp
 	}
 	// body params
 	localVarPostBody = r.client
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}

samples/openapi3/client/petstore/go/go-petstore/api_default.go

@@ -70,9 +70,7 @@ func (a *DefaultApiService) FooGetExecute(r ApiFooGetRequest) (InlineResponseDef
 	var (
 		localVarHTTPMethod   = _nethttp.MethodGet
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  InlineResponseDefault
 	)
 
@@ -104,7 +102,7 @@ func (a *DefaultApiService) FooGetExecute(r ApiFooGetRequest) (InlineResponseDef
 	if localVarHTTPHeaderAccept != "" {
 		localVarHeaderParams["Accept"] = localVarHTTPHeaderAccept
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}

samples/openapi3/client/petstore/go/go-petstore/api_fake.go

@@ -259,9 +259,7 @@ func (a *FakeApiService) FakeHealthGetExecute(r ApiFakeHealthGetRequest) (Health
 	var (
 		localVarHTTPMethod   = _nethttp.MethodGet
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  HealthCheckResult
 	)
 
@@ -293,7 +291,7 @@ func (a *FakeApiService) FakeHealthGetExecute(r ApiFakeHealthGetRequest) (Health
 	if localVarHTTPHeaderAccept != "" {
 		localVarHeaderParams["Accept"] = localVarHTTPHeaderAccept
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}
@@ -367,9 +365,7 @@ func (a *FakeApiService) FakeOuterBooleanSerializeExecute(r ApiFakeOuterBooleanS
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPost
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  bool
 	)
 
@@ -403,7 +399,7 @@ func (a *FakeApiService) FakeOuterBooleanSerializeExecute(r ApiFakeOuterBooleanS
 	}
 	// body params
 	localVarPostBody = r.body
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}
@@ -477,9 +473,7 @@ func (a *FakeApiService) FakeOuterCompositeSerializeExecute(r ApiFakeOuterCompos
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPost
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  OuterComposite
 	)
 
@@ -513,7 +507,7 @@ func (a *FakeApiService) FakeOuterCompositeSerializeExecute(r ApiFakeOuterCompos
 	}
 	// body params
 	localVarPostBody = r.outerComposite
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}
@@ -587,9 +581,7 @@ func (a *FakeApiService) FakeOuterNumberSerializeExecute(r ApiFakeOuterNumberSer
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPost
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  float32
 	)
 
@@ -623,7 +615,7 @@ func (a *FakeApiService) FakeOuterNumberSerializeExecute(r ApiFakeOuterNumberSer
 	}
 	// body params
 	localVarPostBody = r.body
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}
@@ -697,9 +689,7 @@ func (a *FakeApiService) FakeOuterStringSerializeExecute(r ApiFakeOuterStringSer
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPost
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  string
 	)
 
@@ -733,7 +723,7 @@ func (a *FakeApiService) FakeOuterStringSerializeExecute(r ApiFakeOuterStringSer
 	}
 	// body params
 	localVarPostBody = r.body
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}
@@ -805,9 +795,7 @@ func (a *FakeApiService) TestBodyWithFileSchemaExecute(r ApiTestBodyWithFileSche
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPut
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "FakeApiService.TestBodyWithFileSchema")
@@ -843,7 +831,7 @@ func (a *FakeApiService) TestBodyWithFileSchemaExecute(r ApiTestBodyWithFileSche
 	}
 	// body params
 	localVarPostBody = r.fileSchemaTestClass
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}
@@ -909,9 +897,7 @@ func (a *FakeApiService) TestBodyWithQueryParamsExecute(r ApiTestBodyWithQueryPa
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPut
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "FakeApiService.TestBodyWithQueryParams")
@@ -951,7 +937,7 @@ func (a *FakeApiService) TestBodyWithQueryParamsExecute(r ApiTestBodyWithQueryPa
 	}
 	// body params
 	localVarPostBody = r.user
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}
@@ -1016,9 +1002,7 @@ func (a *FakeApiService) TestClientModelExecute(r ApiTestClientModelRequest) (Cl
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPatch
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  Client
 	)
 
@@ -1055,7 +1039,7 @@ func (a *FakeApiService) TestClientModelExecute(r ApiTestClientModelRequest) (Cl
 	}
 	// body params
 	localVarPostBody = r.client
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}
@@ -1210,9 +1194,7 @@ func (a *FakeApiService) TestEndpointParametersExecute(r ApiTestEndpointParamete
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPost
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "FakeApiService.TestEndpointParameters")
@@ -1286,17 +1268,23 @@ func (a *FakeApiService) TestEndpointParametersExecute(r ApiTestEndpointParamete
 	}
 	localVarFormParams.Add("pattern_without_delimiter", parameterToString(*r.patternWithoutDelimiter, ""))
 	localVarFormParams.Add("byte", parameterToString(*r.byte_, ""))
-	localVarFormFileName = "binary"
+	var binaryLocalVarFormFileName string
-	var localVarFile *os.File
+	var binaryLocalVarFileName     string
+	var binaryLocalVarFileBytes    []byte
+
+	binaryLocalVarFormFileName = "binary"
+
+	var binaryLocalVarFile *os.File
 	if r.binary != nil {
-		localVarFile = *r.binary
+		binaryLocalVarFile = *r.binary
 	}
-	if localVarFile != nil {
+	if binaryLocalVarFile != nil {
-		fbs, _ := _ioutil.ReadAll(localVarFile)
+		fbs, _ := _ioutil.ReadAll(binaryLocalVarFile)
-		localVarFileBytes = fbs
+		binaryLocalVarFileBytes = fbs
-		localVarFileName = localVarFile.Name()
+		binaryLocalVarFileName = binaryLocalVarFile.Name()
-		localVarFile.Close()
+		binaryLocalVarFile.Close()
 	}
+	formFiles = append(formFiles, formFile{fileBytes: binaryLocalVarFileBytes, fileName: binaryLocalVarFileName, formFileName: binaryLocalVarFormFileName})
 	if r.date != nil {
 		localVarFormParams.Add("date", parameterToString(*r.date, ""))
 	}
@@ -1309,7 +1297,7 @@ func (a *FakeApiService) TestEndpointParametersExecute(r ApiTestEndpointParamete
 	if r.callback != nil {
 		localVarFormParams.Add("callback", parameterToString(*r.callback, ""))
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}
@@ -1415,9 +1403,7 @@ func (a *FakeApiService) TestEnumParametersExecute(r ApiTestEnumParametersReques
 	var (
 		localVarHTTPMethod   = _nethttp.MethodGet
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "FakeApiService.TestEnumParameters")
@@ -1480,7 +1466,7 @@ func (a *FakeApiService) TestEnumParametersExecute(r ApiTestEnumParametersReques
 	if r.enumFormString != nil {
 		localVarFormParams.Add("enum_form_string", parameterToString(*r.enumFormString, ""))
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}
@@ -1574,9 +1560,7 @@ func (a *FakeApiService) TestGroupParametersExecute(r ApiTestGroupParametersRequ
 	var (
 		localVarHTTPMethod   = _nethttp.MethodDelete
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "FakeApiService.TestGroupParameters")
@@ -1628,7 +1612,7 @@ func (a *FakeApiService) TestGroupParametersExecute(r ApiTestGroupParametersRequ
 	if r.booleanGroup != nil {
 		localVarHeaderParams["boolean_group"] = parameterToString(*r.booleanGroup, "")
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}
@@ -1690,9 +1674,7 @@ func (a *FakeApiService) TestInlineAdditionalPropertiesExecute(r ApiTestInlineAd
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPost
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "FakeApiService.TestInlineAdditionalProperties")
@@ -1728,7 +1710,7 @@ func (a *FakeApiService) TestInlineAdditionalPropertiesExecute(r ApiTestInlineAd
 	}
 	// body params
 	localVarPostBody = r.requestBody
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}
@@ -1796,9 +1778,7 @@ func (a *FakeApiService) TestJsonFormDataExecute(r ApiTestJsonFormDataRequest) (
 	var (
 		localVarHTTPMethod   = _nethttp.MethodGet
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "FakeApiService.TestJsonFormData")
@@ -1837,7 +1817,7 @@ func (a *FakeApiService) TestJsonFormDataExecute(r ApiTestJsonFormDataRequest) (
 	}
 	localVarFormParams.Add("param", parameterToString(*r.param, ""))
 	localVarFormParams.Add("param2", parameterToString(*r.param2, ""))
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}
@@ -1920,9 +1900,7 @@ func (a *FakeApiService) TestQueryParameterCollectionFormatExecute(r ApiTestQuer
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPut
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "FakeApiService.TestQueryParameterCollectionFormat")
@@ -1993,7 +1971,7 @@ func (a *FakeApiService) TestQueryParameterCollectionFormatExecute(r ApiTestQuer
 	if localVarHTTPHeaderAccept != "" {
 		localVarHeaderParams["Accept"] = localVarHTTPHeaderAccept
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}
@@ -2062,9 +2040,7 @@ func (a *FakeApiService) TestUniqueItemsHeaderAndQueryParameterCollectionFormatE
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPut
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  []Pet
 	)
 
@@ -2114,7 +2090,7 @@ func (a *FakeApiService) TestUniqueItemsHeaderAndQueryParameterCollectionFormatE
 		localVarHeaderParams["Accept"] = localVarHTTPHeaderAccept
 	}
 	localVarHeaderParams["headerUnique"] = parameterToString(*r.headerUnique, "csv")
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}

samples/openapi3/client/petstore/go/go-petstore/api_fake_classname_tags123.go

@@ -80,9 +80,7 @@ func (a *FakeClassnameTags123ApiService) TestClassnameExecute(r ApiTestClassname
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPatch
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  Client
 	)
 
@@ -133,7 +131,7 @@ func (a *FakeClassnameTags123ApiService) TestClassnameExecute(r ApiTestClassname
 			}
 		}
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}

samples/openapi3/client/petstore/go/go-petstore/api_pet.go

@@ -183,9 +183,7 @@ func (a *PetApiService) AddPetExecute(r ApiAddPetRequest) (*_nethttp.Response, e
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPost
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "PetApiService.AddPet")
@@ -221,7 +219,7 @@ func (a *PetApiService) AddPetExecute(r ApiAddPetRequest) (*_nethttp.Response, e
 	}
 	// body params
 	localVarPostBody = r.pet
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}
@@ -285,9 +283,7 @@ func (a *PetApiService) DeletePetExecute(r ApiDeletePetRequest) (*_nethttp.Respo
 	var (
 		localVarHTTPMethod   = _nethttp.MethodDelete
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "PetApiService.DeletePet")
@@ -322,7 +318,7 @@ func (a *PetApiService) DeletePetExecute(r ApiDeletePetRequest) (*_nethttp.Respo
 	if r.apiKey != nil {
 		localVarHeaderParams["api_key"] = parameterToString(*r.apiKey, "")
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}
@@ -388,9 +384,7 @@ func (a *PetApiService) FindPetsByStatusExecute(r ApiFindPetsByStatusRequest) ([
 	var (
 		localVarHTTPMethod   = _nethttp.MethodGet
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  []Pet
 	)
 
@@ -426,7 +420,7 @@ func (a *PetApiService) FindPetsByStatusExecute(r ApiFindPetsByStatusRequest) ([
 	if localVarHTTPHeaderAccept != "" {
 		localVarHeaderParams["Accept"] = localVarHTTPHeaderAccept
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}
@@ -503,9 +497,7 @@ func (a *PetApiService) FindPetsByTagsExecute(r ApiFindPetsByTagsRequest) ([]Pet
 	var (
 		localVarHTTPMethod   = _nethttp.MethodGet
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  []Pet
 	)
 
@@ -541,7 +533,7 @@ func (a *PetApiService) FindPetsByTagsExecute(r ApiFindPetsByTagsRequest) ([]Pet
 	if localVarHTTPHeaderAccept != "" {
 		localVarHeaderParams["Accept"] = localVarHTTPHeaderAccept
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}
@@ -612,9 +604,7 @@ func (a *PetApiService) GetPetByIdExecute(r ApiGetPetByIdRequest) (Pet, *_nethtt
 	var (
 		localVarHTTPMethod   = _nethttp.MethodGet
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  Pet
 	)
 
@@ -661,7 +651,7 @@ func (a *PetApiService) GetPetByIdExecute(r ApiGetPetByIdRequest) (Pet, *_nethtt
 			}
 		}
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}
@@ -732,9 +722,7 @@ func (a *PetApiService) UpdatePetExecute(r ApiUpdatePetRequest) (*_nethttp.Respo
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPut
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "PetApiService.UpdatePet")
@@ -770,7 +758,7 @@ func (a *PetApiService) UpdatePetExecute(r ApiUpdatePetRequest) (*_nethttp.Respo
 	}
 	// body params
 	localVarPostBody = r.pet
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}
@@ -841,9 +829,7 @@ func (a *PetApiService) UpdatePetWithFormExecute(r ApiUpdatePetWithFormRequest)
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPost
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "PetApiService.UpdatePetWithForm")
@@ -881,7 +867,7 @@ func (a *PetApiService) UpdatePetWithFormExecute(r ApiUpdatePetWithFormRequest)
 	if r.status != nil {
 		localVarFormParams.Add("status", parameterToString(*r.status, ""))
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}
@@ -953,9 +939,7 @@ func (a *PetApiService) UploadFileExecute(r ApiUploadFileRequest) (ApiResponse,
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPost
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  ApiResponse
 	)
 
@@ -991,18 +975,24 @@ func (a *PetApiService) UploadFileExecute(r ApiUploadFileRequest) (ApiResponse,
 	if r.additionalMetadata != nil {
 		localVarFormParams.Add("additionalMetadata", parameterToString(*r.additionalMetadata, ""))
 	}
-	localVarFormFileName = "file"
+	var fileLocalVarFormFileName string
-	var localVarFile *os.File
+	var fileLocalVarFileName     string
+	var fileLocalVarFileBytes    []byte
+
+	fileLocalVarFormFileName = "file"
+
+	var fileLocalVarFile *os.File
 	if r.file != nil {
-		localVarFile = *r.file
+		fileLocalVarFile = *r.file
 	}
-	if localVarFile != nil {
+	if fileLocalVarFile != nil {
-		fbs, _ := _ioutil.ReadAll(localVarFile)
+		fbs, _ := _ioutil.ReadAll(fileLocalVarFile)
-		localVarFileBytes = fbs
+		fileLocalVarFileBytes = fbs
-		localVarFileName = localVarFile.Name()
+		fileLocalVarFileName = fileLocalVarFile.Name()
-		localVarFile.Close()
+		fileLocalVarFile.Close()
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	formFiles = append(formFiles, formFile{fileBytes: fileLocalVarFileBytes, fileName: fileLocalVarFileName, formFileName: fileLocalVarFormFileName})
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}
@@ -1083,9 +1073,7 @@ func (a *PetApiService) UploadFileWithRequiredFileExecute(r ApiUploadFileWithReq
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPost
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  ApiResponse
 	)
 
@@ -1124,15 +1112,21 @@ func (a *PetApiService) UploadFileWithRequiredFileExecute(r ApiUploadFileWithReq
 	if r.additionalMetadata != nil {
 		localVarFormParams.Add("additionalMetadata", parameterToString(*r.additionalMetadata, ""))
 	}
-	localVarFormFileName = "requiredFile"
+	var requiredFileLocalVarFormFileName string
-	localVarFile := *r.requiredFile
+	var requiredFileLocalVarFileName     string
-	if localVarFile != nil {
+	var requiredFileLocalVarFileBytes    []byte
-		fbs, _ := _ioutil.ReadAll(localVarFile)
+
-		localVarFileBytes = fbs
+	requiredFileLocalVarFormFileName = "requiredFile"
-		localVarFileName = localVarFile.Name()
+
-		localVarFile.Close()
+	requiredFileLocalVarFile := *r.requiredFile
+	if requiredFileLocalVarFile != nil {
+		fbs, _ := _ioutil.ReadAll(requiredFileLocalVarFile)
+		requiredFileLocalVarFileBytes = fbs
+		requiredFileLocalVarFileName = requiredFileLocalVarFile.Name()
+		requiredFileLocalVarFile.Close()
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	formFiles = append(formFiles, formFile{fileBytes: requiredFileLocalVarFileBytes, fileName: requiredFileLocalVarFileName, formFileName: requiredFileLocalVarFormFileName})
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}

samples/openapi3/client/petstore/go/go-petstore/api_store.go

@@ -118,9 +118,7 @@ func (a *StoreApiService) DeleteOrderExecute(r ApiDeleteOrderRequest) (*_nethttp
 	var (
 		localVarHTTPMethod   = _nethttp.MethodDelete
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "StoreApiService.DeleteOrder")
@@ -152,7 +150,7 @@ func (a *StoreApiService) DeleteOrderExecute(r ApiDeleteOrderRequest) (*_nethttp
 	if localVarHTTPHeaderAccept != "" {
 		localVarHeaderParams["Accept"] = localVarHTTPHeaderAccept
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}
@@ -211,9 +209,7 @@ func (a *StoreApiService) GetInventoryExecute(r ApiGetInventoryRequest) (map[str
 	var (
 		localVarHTTPMethod   = _nethttp.MethodGet
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  map[string]int32
 	)
 
@@ -259,7 +255,7 @@ func (a *StoreApiService) GetInventoryExecute(r ApiGetInventoryRequest) (map[str
 			}
 		}
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}
@@ -330,9 +326,7 @@ func (a *StoreApiService) GetOrderByIdExecute(r ApiGetOrderByIdRequest) (Order,
 	var (
 		localVarHTTPMethod   = _nethttp.MethodGet
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  Order
 	)
 
@@ -371,7 +365,7 @@ func (a *StoreApiService) GetOrderByIdExecute(r ApiGetOrderByIdRequest) (Order,
 	if localVarHTTPHeaderAccept != "" {
 		localVarHeaderParams["Accept"] = localVarHTTPHeaderAccept
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}
@@ -443,9 +437,7 @@ func (a *StoreApiService) PlaceOrderExecute(r ApiPlaceOrderRequest) (Order, *_ne
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPost
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  Order
 	)
 
@@ -482,7 +474,7 @@ func (a *StoreApiService) PlaceOrderExecute(r ApiPlaceOrderRequest) (Order, *_ne
 	}
 	// body params
 	localVarPostBody = r.order
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}

samples/openapi3/client/petstore/go/go-petstore/api_user.go

@@ -165,9 +165,7 @@ func (a *UserApiService) CreateUserExecute(r ApiCreateUserRequest) (*_nethttp.Re
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPost
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "UserApiService.CreateUser")
@@ -203,7 +201,7 @@ func (a *UserApiService) CreateUserExecute(r ApiCreateUserRequest) (*_nethttp.Re
 	}
 	// body params
 	localVarPostBody = r.user
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}
@@ -265,9 +263,7 @@ func (a *UserApiService) CreateUsersWithArrayInputExecute(r ApiCreateUsersWithAr
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPost
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "UserApiService.CreateUsersWithArrayInput")
@@ -303,7 +299,7 @@ func (a *UserApiService) CreateUsersWithArrayInputExecute(r ApiCreateUsersWithAr
 	}
 	// body params
 	localVarPostBody = r.user
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}
@@ -365,9 +361,7 @@ func (a *UserApiService) CreateUsersWithListInputExecute(r ApiCreateUsersWithLis
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPost
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "UserApiService.CreateUsersWithListInput")
@@ -403,7 +397,7 @@ func (a *UserApiService) CreateUsersWithListInputExecute(r ApiCreateUsersWithLis
 	}
 	// body params
 	localVarPostBody = r.user
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}
@@ -464,9 +458,7 @@ func (a *UserApiService) DeleteUserExecute(r ApiDeleteUserRequest) (*_nethttp.Re
 	var (
 		localVarHTTPMethod   = _nethttp.MethodDelete
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "UserApiService.DeleteUser")
@@ -498,7 +490,7 @@ func (a *UserApiService) DeleteUserExecute(r ApiDeleteUserRequest) (*_nethttp.Re
 	if localVarHTTPHeaderAccept != "" {
 		localVarHeaderParams["Accept"] = localVarHTTPHeaderAccept
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}
@@ -558,9 +550,7 @@ func (a *UserApiService) GetUserByNameExecute(r ApiGetUserByNameRequest) (User,
 	var (
 		localVarHTTPMethod   = _nethttp.MethodGet
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  User
 	)
 
@@ -593,7 +583,7 @@ func (a *UserApiService) GetUserByNameExecute(r ApiGetUserByNameRequest) (User,
 	if localVarHTTPHeaderAccept != "" {
 		localVarHeaderParams["Accept"] = localVarHTTPHeaderAccept
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}
@@ -671,9 +661,7 @@ func (a *UserApiService) LoginUserExecute(r ApiLoginUserRequest) (string, *_neth
 	var (
 		localVarHTTPMethod   = _nethttp.MethodGet
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 		localVarReturnValue  string
 	)
 
@@ -713,7 +701,7 @@ func (a *UserApiService) LoginUserExecute(r ApiLoginUserRequest) (string, *_neth
 	if localVarHTTPHeaderAccept != "" {
 		localVarHeaderParams["Accept"] = localVarHTTPHeaderAccept
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return localVarReturnValue, nil, err
 	}
@@ -778,9 +766,7 @@ func (a *UserApiService) LogoutUserExecute(r ApiLogoutUserRequest) (*_nethttp.Re
 	var (
 		localVarHTTPMethod   = _nethttp.MethodGet
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "UserApiService.LogoutUser")
@@ -811,7 +797,7 @@ func (a *UserApiService) LogoutUserExecute(r ApiLogoutUserRequest) (*_nethttp.Re
 	if localVarHTTPHeaderAccept != "" {
 		localVarHeaderParams["Accept"] = localVarHTTPHeaderAccept
 	}
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}
@@ -878,9 +864,7 @@ func (a *UserApiService) UpdateUserExecute(r ApiUpdateUserRequest) (*_nethttp.Re
 	var (
 		localVarHTTPMethod   = _nethttp.MethodPut
 		localVarPostBody     interface{}
-		localVarFormFileName string
+		formFiles            []formFile
-		localVarFileName     string
-		localVarFileBytes    []byte
 	)
 
 	localBasePath, err := a.client.cfg.ServerURLWithContext(r.ctx, "UserApiService.UpdateUser")
@@ -917,7 +901,7 @@ func (a *UserApiService) UpdateUserExecute(r ApiUpdateUserRequest) (*_nethttp.Re
 	}
 	// body params
 	localVarPostBody = r.user
-	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, localVarFormFileName, localVarFileName, localVarFileBytes)
+	req, err := a.client.prepareRequest(r.ctx, localVarPath, localVarHTTPMethod, localVarPostBody, localVarHeaderParams, localVarQueryParams, localVarFormParams, formFiles)
 	if err != nil {
 		return nil, err
 	}

samples/openapi3/client/petstore/go/go-petstore/client.go

@@ -207,6 +207,12 @@ func (c *APIClient) GetConfig() *Configuration {
 	return c.cfg
 }
 
+type formFile struct {
+		fileBytes []byte
+		fileName string
+		formFileName string
+}
+
 // prepareRequest build the request
 func (c *APIClient) prepareRequest(
 	ctx context.Context,
@@ -215,9 +221,7 @@ func (c *APIClient) prepareRequest(
 	headerParams map[string]string,
 	queryParams url.Values,
 	formParams url.Values,
-	formFileName string,
+	formFiles []formFile) (localVarRequest *http.Request, err error) {
-	fileName string,
-	fileBytes []byte) (localVarRequest *http.Request, err error) {
 
 	var body *bytes.Buffer
 
@@ -236,7 +240,7 @@ func (c *APIClient) prepareRequest(
 	}
 
 	// add form parameters and file if available.
-	if strings.HasPrefix(headerParams["Content-Type"], "multipart/form-data") && len(formParams) > 0 || (len(fileBytes) > 0 && fileName != "") {
+	if strings.HasPrefix(headerParams["Content-Type"], "multipart/form-data") && len(formParams) > 0 || (len(formFiles) > 0) {
 		if body != nil {
 			return nil, errors.New("Cannot specify postBody and multipart form at the same time.")
 		}
@@ -255,18 +259,19 @@ func (c *APIClient) prepareRequest(
 				}
 			}
 		}
-		if len(fileBytes) > 0 && fileName != "" {
+		for _, formFile := range formFiles {
+			if len(formFile.fileBytes) > 0 && formFile.fileName != "" {
 				w.Boundary()
-			//_, fileNm := filepath.Split(fileName)
+				part, err := w.CreateFormFile(formFile.formFileName, filepath.Base(formFile.fileName))
-			part, err := w.CreateFormFile(formFileName, filepath.Base(fileName))
 				if err != nil {
 						return nil, err
 				}
-			_, err = part.Write(fileBytes)
+				_, err = part.Write(formFile.fileBytes)
 				if err != nil {
 						return nil, err
 				}
 			}
+		}
 
 		// Set the Boundary in the Content-Type
 		headerParams["Content-Type"] = w.FormDataContentType()