[Go-Server] Support for an endpoint returning a file to the client - #15206 (#16748)

* Support for an endpoint returning a file to a client.

* Spaces to tabs conversion

* Add an example endpoint for download a file

* Regenerate after merging main

.gitignore

@@ -49,6 +49,8 @@ nb-configuration.xml
 /target
 /generated-files
 test-output/
+nbactions.xml
+test-output/
 
 # website
 website/build/
@@ -71,6 +73,7 @@ samples/client/petstore/build
 samples/client/petstore/cpp-qt/PetStore/moc_*
 samples/client/petstore/cpp-qt/PetStore/*.o
 samples/client/petstore/cpp-qt/build-*
+samples/client/petstore/cpp-qt/build-*
 samples/client/petstore/cpp-qt/PetStore/PetStore
 samples/client/petstore/cpp-qt/PetStore/Makefile
 samples/client/petstore/cpp-qt/PetStore/PetStore.pro.user
@@ -97,7 +100,9 @@ samples/client/petstore/java/jersey2/build/
 samples/client/petstore/java/okhttp-gson/.gradle/
 samples/client/petstore/java/okhttp-gson/build/
 samples/client/petstore/java/feign/build/
+samples/client/petstore/java/feign10x/build/
 samples/client/petstore/java/feign/project/
+samples/client/petstore/java/feign10x/project/
 samples/client/petstore/java/retrofit/build/
 samples/client/petstore/java/retrofit2/build/
 samples/client/petstore/java/retrofit2/hello.txt
@@ -105,6 +110,7 @@ samples/client/petstore/java/retrofit2rx/build/
 samples/client/petstore/java/default/build/
 samples/client/petstore/scala/build/
 samples/client/petstore/java/resttemplate/hello.txt
+samples/client/petstore/java/retrofit2/hello.txt
 samples/client/petstore/java/feign/hello.txt
 samples/client/petstore/java/jersey2-java6/project/
 samples/client/petstore/java/jersey2-java8/project/
@@ -187,7 +193,6 @@ samples/server/petstore/php-slim4/composer.lock
 samples/server/petstore/php-symfony/SymfonyBundle-php/composer.lock
 samples/server/petstore/php-mezzio-ph/composer.lock
 samples/server/petstore/php-mezzio-ph-modern/composer.lock
-samples/client/petstore/php-nextgen/OpenAPIClient-php/.phplint.cache/
 
 # ts
 samples/client/petstore/typescript-angular2/npm/npm-debug.log

modules/openapi-generator/src/main/resources/go-server/routers.mustache

@@ -89,18 +89,33 @@ func NewRouter(routers ...Router) {{#routers}}{{#mux}}*mux.Router{{/mux}}{{#chi}
 
 // EncodeJSONResponse uses the json encoder to write an interface to the http response with an optional status code
 func EncodeJSONResponse(i interface{}, status *int,{{#addResponseHeaders}} headers map[string][]string,{{/addResponseHeaders}} w http.ResponseWriter) error {
-	{{#addResponseHeaders}}
 	wHeader := w.Header()
+	{{#addResponseHeaders}}
 	for key, values := range headers {
 		for _, value := range values {
 			wHeader.Add(key, value)
 		}
 	}
+	{{/addResponseHeaders}}
+
+	f, ok := i.(*os.File)
+	if ok {
+		data, err := io.ReadAll(f)
+		if err != nil {
+			return err
+		}
+		wHeader.Set("Content-Type", http.DetectContentType(data))
+		wHeader.Set("Content-Disposition", "attachment; filename="+f.Name())
+		if status != nil {
+			w.WriteHeader(*status)
+		} else {
+			w.WriteHeader(http.StatusOK)
+		}
+		_, err = w.Write(data)
+		return err
+	}
 	wHeader.Set("Content-Type", "application/json; charset=UTF-8")
-	{{/addResponseHeaders}}
-	{{^addResponseHeaders}}
-	w.Header().Set("Content-Type", "application/json; charset=UTF-8")
-	{{/addResponseHeaders}}
+
 	if status != nil {
 		w.WriteHeader(*status)
 	} else {

modules/openapi-generator/src/test/resources/3_0/go-server/petstore.yaml

@@ -332,6 +332,32 @@ paths:
                   description: file to upload
                   type: string
                   format: binary
+    get:
+      tags:
+        - pet
+      summary: Returns the image for the Pet that has been previously uploaded
+      description: Returns the image for the Pet that has been previously uploaded
+      operationId: getPetImageById
+      parameters:
+        - name: petId
+          in: path
+          description: ID of pet to return
+          required: true
+          schema:
+            type: integer
+            format: int64
+      responses:
+        '200':
+          description: successful operation
+          content:
+            image/jpeg:
+              schema:
+                type: string
+                format: binary
+        '400':
+          description: Invalid ID supplied
+        '404':
+          description: Pet not found
   /store/inventory:
     get:
       tags:

samples/openapi3/server/petstore/go/go-petstore/go/routers.go

@@ -64,7 +64,25 @@ func EncodeJSONResponse(i interface{}, status *int, headers map[string][]string,
 			wHeader.Add(key, value)
 		}
 	}
+
+	f, ok := i.(*os.File)
+	if ok {
+		data, err := io.ReadAll(f)
+		if err != nil {
+			return err
+		}
+		wHeader.Set("Content-Type", http.DetectContentType(data))
+		wHeader.Set("Content-Disposition", "attachment; filename="+f.Name())
+		if status != nil {
+			w.WriteHeader(*status)
+		} else {
+			w.WriteHeader(http.StatusOK)
+		}
+		_, err = w.Write(data)
+		return err
+	}
 	wHeader.Set("Content-Type", "application/json; charset=UTF-8")
+
 	if status != nil {
 		w.WriteHeader(*status)
 	} else {

samples/server/petstore/go-api-server/api/openapi.yaml

@@ -298,6 +298,34 @@ paths:
       tags:
       - pet
   /pet/{petId}/uploadImage:
+    get:
+      description: Returns the image for the Pet that has been previously uploaded
+      operationId: getPetImageById
+      parameters:
+      - description: ID of pet to return
+        explode: false
+        in: path
+        name: petId
+        required: true
+        schema:
+          format: int64
+          type: integer
+        style: simple
+      responses:
+        "200":
+          content:
+            image/jpeg:
+              schema:
+                format: binary
+                type: string
+          description: successful operation
+        "400":
+          description: Invalid ID supplied
+        "404":
+          description: Pet not found
+      summary: Returns the image for the Pet that has been previously uploaded
+      tags:
+      - pet
     post:
       description: ""
       operationId: uploadFile

samples/server/petstore/go-api-server/go/api.go

@@ -28,6 +28,7 @@ type PetAPIRouter interface {
 	// Deprecated
 	FindPetsByTags(http.ResponseWriter, *http.Request)
 	GetPetById(http.ResponseWriter, *http.Request)
+	GetPetImageById(http.ResponseWriter, *http.Request)
 	UpdatePet(http.ResponseWriter, *http.Request)
 	UpdatePetWithForm(http.ResponseWriter, *http.Request)
 	UploadFile(http.ResponseWriter, *http.Request)
@@ -69,6 +70,7 @@ type PetAPIServicer interface {
 	// Deprecated
 	FindPetsByTags(context.Context, []string) (ImplResponse, error)
 	GetPetById(context.Context, int64) (ImplResponse, error)
+	GetPetImageById(context.Context, int64) (ImplResponse, error)
 	UpdatePet(context.Context, Pet) (ImplResponse, error)
 	UpdatePetWithForm(context.Context, int64, string, string) (ImplResponse, error)
 	UploadFile(context.Context, int64, string, *os.File) (ImplResponse, error)

samples/server/petstore/go-api-server/go/api_pet.go

@@ -80,6 +80,11 @@ func (c *PetAPIController) Routes() Routes {
 			"/v2/pet/{petId}",
 			c.GetPetById,
 		},
+		"GetPetImageById": Route{
+			strings.ToUpper("Get"),
+			"/v2/pet/{petId}/uploadImage",
+			c.GetPetImageById,
+		},
 		"UpdatePet": Route{
 			strings.ToUpper("Put"),
 			"/v2/pet",
@@ -249,6 +254,27 @@ func (c *PetAPIController) GetPetById(w http.ResponseWriter, r *http.Request) {
 	EncodeJSONResponse(result.Body, &result.Code, result.Headers, w)
 }
 
+// GetPetImageById - Returns the image for the Pet that has been previously uploaded
+func (c *PetAPIController) GetPetImageById(w http.ResponseWriter, r *http.Request) {
+	params := mux.Vars(r)
+	petIdParam, err := parseNumericParameter[int64](
+		params["petId"],
+		WithRequire[int64](parseInt64),
+	)
+	if err != nil {
+		c.errorHandler(w, r, &ParsingError{Err: err}, nil)
+		return
+	}
+	result, err := c.service.GetPetImageById(r.Context(), petIdParam)
+	// If an error occurred, encode the error with the status code
+	if err != nil {
+		c.errorHandler(w, r, err, &result)
+		return
+	}
+	// If no error, encode the body and the result code
+	EncodeJSONResponse(result.Body, &result.Code, result.Headers, w)
+}
+
 // UpdatePet - Update an existing pet
 func (c *PetAPIController) UpdatePet(w http.ResponseWriter, r *http.Request) {
 	petParam := Pet{}

samples/server/petstore/go-api-server/go/api_pet_service.go

@@ -112,6 +112,23 @@ func (s *PetAPIService) GetPetById(ctx context.Context, petId int64) (ImplRespon
 	return Response(http.StatusNotImplemented, nil), errors.New("GetPetById method not implemented")
 }
 
+// GetPetImageById - Returns the image for the Pet that has been previously uploaded
+func (s *PetAPIService) GetPetImageById(ctx context.Context, petId int64) (ImplResponse, error) {
+	// TODO - update GetPetImageById with the required logic for this service method.
+	// Add api_pet_service.go to the .openapi-generator-ignore to avoid overwriting this service implementation when updating open api generation.
+
+	// TODO: Uncomment the next line to return response Response(200, *os.File{}) or use other options such as http.Ok ...
+	// return Response(200, *os.File{}), nil
+
+	// TODO: Uncomment the next line to return response Response(400, {}) or use other options such as http.Ok ...
+	// return Response(400, nil),nil
+
+	// TODO: Uncomment the next line to return response Response(404, {}) or use other options such as http.Ok ...
+	// return Response(404, nil),nil
+
+	return Response(http.StatusNotImplemented, nil), errors.New("GetPetImageById method not implemented")
+}
+
 // UpdatePet - Update an existing pet
 func (s *PetAPIService) UpdatePet(ctx context.Context, pet Pet) (ImplResponse, error) {
 	// TODO - update UpdatePet with the required logic for this service method.

samples/server/petstore/go-api-server/go/routers.go

@@ -68,7 +68,25 @@ func EncodeJSONResponse(i interface{}, status *int, headers map[string][]string,
 			wHeader.Add(key, value)
 		}
 	}
+
+	f, ok := i.(*os.File)
+	if ok {
+		data, err := io.ReadAll(f)
+		if err != nil {
+			return err
+		}
+		wHeader.Set("Content-Type", http.DetectContentType(data))
+		wHeader.Set("Content-Disposition", "attachment; filename="+f.Name())
+		if status != nil {
+			w.WriteHeader(*status)
+		} else {
+			w.WriteHeader(http.StatusOK)
+		}
+		_, err = w.Write(data)
+		return err
+	}
 	wHeader.Set("Content-Type", "application/json; charset=UTF-8")
+
 	if status != nil {
 		w.WriteHeader(*status)
 	} else {

samples/server/petstore/go-chi-server/api/openapi.yaml

@@ -298,6 +298,34 @@ paths:
       tags:
       - pet
   /pet/{petId}/uploadImage:
+    get:
+      description: Returns the image for the Pet that has been previously uploaded
+      operationId: getPetImageById
+      parameters:
+      - description: ID of pet to return
+        explode: false
+        in: path
+        name: petId
+        required: true
+        schema:
+          format: int64
+          type: integer
+        style: simple
+      responses:
+        "200":
+          content:
+            image/jpeg:
+              schema:
+                format: binary
+                type: string
+          description: successful operation
+        "400":
+          description: Invalid ID supplied
+        "404":
+          description: Pet not found
+      summary: Returns the image for the Pet that has been previously uploaded
+      tags:
+      - pet
     post:
       description: ""
       operationId: uploadFile

samples/server/petstore/go-chi-server/go/api.go

@@ -28,6 +28,7 @@ type PetAPIRouter interface {
 	// Deprecated
 	FindPetsByTags(http.ResponseWriter, *http.Request)
 	GetPetById(http.ResponseWriter, *http.Request)
+	GetPetImageById(http.ResponseWriter, *http.Request)
 	UpdatePet(http.ResponseWriter, *http.Request)
 	UpdatePetWithForm(http.ResponseWriter, *http.Request)
 	UploadFile(http.ResponseWriter, *http.Request)
@@ -69,6 +70,7 @@ type PetAPIServicer interface {
 	// Deprecated
 	FindPetsByTags(context.Context, []string) (ImplResponse, error)
 	GetPetById(context.Context, int64) (ImplResponse, error)
+	GetPetImageById(context.Context, int64) (ImplResponse, error)
 	UpdatePet(context.Context, Pet) (ImplResponse, error)
 	UpdatePetWithForm(context.Context, int64, string, string) (ImplResponse, error)
 	UploadFile(context.Context, int64, string, *os.File) (ImplResponse, error)

samples/server/petstore/go-chi-server/go/api_pet.go

@@ -80,6 +80,11 @@ func (c *PetAPIController) Routes() Routes {
 			"/v2/pet/{petId}",
 			c.GetPetById,
 		},
+		"GetPetImageById": Route{
+			strings.ToUpper("Get"),
+			"/v2/pet/{petId}/uploadImage",
+			c.GetPetImageById,
+		},
 		"UpdatePet": Route{
 			strings.ToUpper("Put"),
 			"/v2/pet",
@@ -246,6 +251,26 @@ func (c *PetAPIController) GetPetById(w http.ResponseWriter, r *http.Request) {
 	EncodeJSONResponse(result.Body, &result.Code, result.Headers, w)
 }
 
+// GetPetImageById - Returns the image for the Pet that has been previously uploaded
+func (c *PetAPIController) GetPetImageById(w http.ResponseWriter, r *http.Request) {
+	petIdParam, err := parseNumericParameter[int64](
+		chi.URLParam(r, "petId"),
+		WithRequire[int64](parseInt64),
+	)
+	if err != nil {
+		c.errorHandler(w, r, &ParsingError{Err: err}, nil)
+		return
+	}
+	result, err := c.service.GetPetImageById(r.Context(), petIdParam)
+	// If an error occurred, encode the error with the status code
+	if err != nil {
+		c.errorHandler(w, r, err, &result)
+		return
+	}
+	// If no error, encode the body and the result code
+	EncodeJSONResponse(result.Body, &result.Code, result.Headers, w)
+}
+
 // UpdatePet - Update an existing pet
 func (c *PetAPIController) UpdatePet(w http.ResponseWriter, r *http.Request) {
 	petParam := Pet{}

samples/server/petstore/go-chi-server/go/api_pet_service.go

@@ -112,6 +112,23 @@ func (s *PetAPIService) GetPetById(ctx context.Context, petId int64) (ImplRespon
 	return Response(http.StatusNotImplemented, nil), errors.New("GetPetById method not implemented")
 }
 
+// GetPetImageById - Returns the image for the Pet that has been previously uploaded
+func (s *PetAPIService) GetPetImageById(ctx context.Context, petId int64) (ImplResponse, error) {
+	// TODO - update GetPetImageById with the required logic for this service method.
+	// Add api_pet_service.go to the .openapi-generator-ignore to avoid overwriting this service implementation when updating open api generation.
+
+	// TODO: Uncomment the next line to return response Response(200, *os.File{}) or use other options such as http.Ok ...
+	// return Response(200, *os.File{}), nil
+
+	// TODO: Uncomment the next line to return response Response(400, {}) or use other options such as http.Ok ...
+	// return Response(400, nil),nil
+
+	// TODO: Uncomment the next line to return response Response(404, {}) or use other options such as http.Ok ...
+	// return Response(404, nil),nil
+
+	return Response(http.StatusNotImplemented, nil), errors.New("GetPetImageById method not implemented")
+}
+
 // UpdatePet - Update an existing pet
 func (s *PetAPIService) UpdatePet(ctx context.Context, pet Pet) (ImplResponse, error) {
 	// TODO - update UpdatePet with the required logic for this service method.

samples/server/petstore/go-chi-server/go/routers.go

@@ -64,7 +64,25 @@ func EncodeJSONResponse(i interface{}, status *int, headers map[string][]string,
 			wHeader.Add(key, value)
 		}
 	}
+
+	f, ok := i.(*os.File)
+	if ok {
+		data, err := io.ReadAll(f)
+		if err != nil {
+			return err
+		}
+		wHeader.Set("Content-Type", http.DetectContentType(data))
+		wHeader.Set("Content-Disposition", "attachment; filename="+f.Name())
+		if status != nil {
+			w.WriteHeader(*status)
+		} else {
+			w.WriteHeader(http.StatusOK)
+		}
+		_, err = w.Write(data)
+		return err
+	}
 	wHeader.Set("Content-Type", "application/json; charset=UTF-8")
+
 	if status != nil {
 		w.WriteHeader(*status)
 	} else {