[R][httr2] fix HTTP header (#13066)

* add test for header parameters

* fix header parameter in r httr2 client

modules/openapi-generator/src/main/resources/r/libraries/httr2/api_client.mustache

@@ -185,14 +185,10 @@ ApiClient  <- R6::R6Class(
 
       ## add headers and default headers
       if (!is.null(header_params) && length(header_params) != 0) {
-        for (http_header in names(header_params)) {
+        req <- req %>% req_headers(!!!header_params)
-          req <- req %>% req_headers(http_header = header_params[http_header])
-        }
       }
       if (!is.null(self$default_headers) && length(self$default_headers) != 0) {
-        for (http_header in names(header_params)) {
+        req <- req %>% req_headers(!!!self$default_headers)
-          req <- req %>% req_headers(http_header = self$default_headers[http_header])
-        }
       }
 
       # set HTTP accept header

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

@@ -242,6 +242,38 @@ paths:
         - petstore_auth:
             - 'write:pets'
             - 'read:pets'
+  '/pet_header_test':
+    get:
+      tags:
+        - pet
+      summary: Header test
+      description: Header test
+      operationId: test_header
+      x-streaming: true
+      parameters:
+        - name: header_test_int
+          in: header
+          description: header test int
+          required: true
+          schema:
+            type: integer
+            format: int64
+      responses:
+        '200':
+          description: successful operation
+          content:
+            application/xml:
+              schema:
+                $ref: '#/components/schemas/Pet'
+            application/json:
+              schema:
+                $ref: '#/components/schemas/Pet'
+        '400':
+          description: Invalid ID supplied
+        '404':
+          description: Pet not found
+      security:
+        - api_key: []
   '/pet/{petId}?streaming':
     get:
       tags:

samples/client/petstore/R-httr2/R/api_client.R

@@ -190,14 +190,10 @@ ApiClient  <- R6::R6Class(
 
       ## add headers and default headers
       if (!is.null(header_params) && length(header_params) != 0) {
-        for (http_header in names(header_params)) {
+        req <- req %>% req_headers(!!!header_params)
-          req <- req %>% req_headers(http_header = header_params[http_header])
-        }
       }
       if (!is.null(self$default_headers) && length(self$default_headers) != 0) {
-        for (http_header in names(header_params)) {
+        req <- req %>% req_headers(!!!self$default_headers)
-          req <- req %>% req_headers(http_header = self$default_headers[http_header])
-        }
       }
 
       # set HTTP accept header

samples/client/petstore/R-httr2/R/pet_api.R

@@ -171,6 +171,38 @@
 #' }
 #' }
 #'
+#' \strong{ test_header } \emph{ Header test }
+#' Header test
+#'
+#' \itemize{
+#' \item \emph{ @param } header_test_int integer
+#' \item \emph{ @returnType } \link{Pet} \cr
+#'
+#' \item On encountering errors, an error of subclass ApiException will be thrown.
+#'
+#' \item status code : 200 | successful operation
+#'
+#' \item return type : Pet
+#' \item response headers :
+#'
+#' \tabular{ll}{
+#' }
+#' \item status code : 400 | Invalid ID supplied
+#'
+#'
+#' \item response headers :
+#'
+#' \tabular{ll}{
+#' }
+#' \item status code : 404 | Pet not found
+#'
+#'
+#' \item response headers :
+#'
+#' \tabular{ll}{
+#' }
+#' }
+#'
 #' \strong{ update_pet } \emph{ Update an existing pet }
 #' 
 #'
@@ -424,6 +456,34 @@
 #' }
 #'
 #'
+#' ####################  test_header  ####################
+#'
+#' library(petstore)
+#' var.header_test_int <- 56 # integer | header test int
+#'
+#' #Header test
+#' api.instance <- PetApi$new()
+#'
+#' #Configure API key authorization: api_key
+#' api.instance$api_client$api_keys['api_key'] <- 'TODO_YOUR_API_KEY';
+#'
+#'result <- tryCatch(
+#'             api.instance$test_header(var.header_test_int),
+#'             ApiException = function(ex) ex
+#'          )
+#' # In case of error, print the error object
+#' if(!is.null(result$ApiException)) {
+#'   cat(result$ApiException$toString())
+#' } else {
+#' # deserialized response object
+#' response.object <- result$content
+#' # response headers
+#' response.headers <- result$response$headers
+#' # response status code
+#' response.status.code <- result$response$status_code
+#' }
+#'
+#'
 #' ####################  update_pet  ####################
 #'
 #' library(petstore)
@@ -1197,6 +1257,127 @@ PetApi <- R6::R6Class(
                      ApiException = ApiException$new(http_response = local_var_resp))
       }
     },
+    #' Header test
+    #'
+    #' @description
+    #' Header test
+    #'
+    #' @param header_test_int header test int
+    #' @param stream_callback (optional) callback function to process the data stream
+    #' @param data_file (optional) name of the data file to save the result
+    #' @param ... Other optional arguments
+    #' @return Pet
+    #' @export
+    test_header = function(header_test_int, stream_callback = NULL, data_file = NULL, ...) {
+      local_var_response <- self$test_header_with_http_info(header_test_int, stream_callback = stream_callback, data_file = data_file, ...)
+      if (typeof(stream_callback) == "closure") { # return void if streaming is enabled
+        return(invisible(NULL))
+      }
+
+      if (local_var_response$status_code >= 200 && local_var_response$status_code <= 299) {
+        local_var_response$content
+      } else if (local_var_response$status_code >= 300 && local_var_response$status_code <= 399) {
+        local_var_response
+      } else if (local_var_response$status_code >= 400 && local_var_response$status_code <= 499) {
+        local_var_response
+      } else if (local_var_response$status_code >= 500 && local_var_response$status_code <= 599) {
+        local_var_response
+      }
+    },
+    #' Header test
+    #'
+    #' @description
+    #' Header test
+    #'
+    #' @param header_test_int header test int
+    #' @param stream_callback (optional) callback function to process the data stream
+    #' @param data_file (optional) name of the data file to save the result
+    #' @param ... Other optional arguments
+    #' @return API response (Pet) with additional information such as HTTP status code, headers
+    #' @export
+    test_header_with_http_info = function(header_test_int, stream_callback = NULL, data_file = NULL, ...) {
+      args <- list(...)
+      query_params <- list()
+      header_params <- c()
+
+      if (missing(`header_test_int`)) {
+        rlang::abort(message = "Missing required parameter `header_test_int`.",
+                     .subclass = "ApiException",
+                     ApiException = ApiException$new(status = 0,
+                                                     reason = "Missing required parameter `header_test_int`."))
+      }
+
+      header_params["header_test_int"] <- `header_test_int`
+
+      local_var_body <- NULL
+      local_var_url_path <- "/pet_header_test"
+      # API key authentication
+      if ("api_key" %in% names(self$api_client$api_keys) && nchar(self$api_client$api_keys["api_key"]) > 0) {
+        header_params["api_key"] <- paste(unlist(self$api_client$api_keys["api_key"]), collapse = "")
+      }
+
+      # The Accept request HTTP header
+      local_var_accepts = list("application/xml", "application/json")
+
+      # The Content-Type representation header
+      local_var_content_types = list()
+
+      local_var_resp <- self$api_client$CallApi(url = paste0(self$api_client$base_path, local_var_url_path),
+                                 method = "GET",
+                                 query_params = query_params,
+                                 header_params = header_params,
+                                 accepts = local_var_accepts,
+                                 content_types = local_var_content_types,
+                                 body = local_var_body,
+                                 stream_callback = stream_callback,
+                                 ...)
+
+      if (typeof(stream_callback) == "closure") { # return void if streaming is enabled
+        return(invisible(NULL))
+      }
+
+      if (local_var_resp$status_code >= 200 && local_var_resp$status_code <= 299) {
+        # save response in a file
+        if (!is.null(data_file)) {
+            write(local_var_resp$response, data_file)
+        }
+
+        deserialized_resp_obj <- tryCatch(
+          self$api_client$deserialize(local_var_resp$response, "Pet", loadNamespace("petstore")),
+          error = function(e) {
+             rlang::abort(message = "Failed to deserialize response",
+                          .subclass = "ApiException",
+                          ApiException = ApiException$new(http_response = local_var_resp))
+          }
+        )
+        local_var_resp$content <- deserialized_resp_obj
+        local_var_resp
+      } else if (local_var_resp$status_code >= 300 && local_var_resp$status_code <= 399) {
+        local_var_error_msg <- local_var_resp$response
+        if (local_var_error_msg == "") {
+          local_var_error_msg <- paste("Server returned ", local_var_resp$status_code, " response status code.")
+        }
+        rlang::abort(message = local_var_error_msg,
+                     .subclass = "ApiException",
+                     ApiException = ApiException$new(http_response = local_var_resp))
+      } else if (local_var_resp$status_code >= 400 && local_var_resp$status_code <= 499) {
+        local_var_error_msg <- local_var_resp$response
+        if (local_var_error_msg == "") {
+          local_var_error_msg <- "Api client exception encountered."
+        }
+        rlang::abort(message = local_var_error_msg,
+                     .subclass = "ApiException",
+                     ApiException = ApiException$new(http_response = local_var_resp))
+      } else if (local_var_resp$status_code >= 500 && local_var_resp$status_code <= 599) {
+        local_var_error_msg <- local_var_resp$response
+        if (local_var_error_msg == "") {
+          local_var_error_msg <- "Api server exception encountered."
+        }
+        rlang::abort(message = error_msg,
+                     .subclass = "ApiException",
+                     ApiException = ApiException$new(http_response = local_var_resp))
+      }
+    },
     #' Update an existing pet
     #'
     #' @description

samples/client/petstore/R-httr2/README.md

@@ -68,6 +68,7 @@ Class | Method | HTTP request | Description
 *PetApi* | [**find_pets_by_tags**](docs/PetApi.md#find_pets_by_tags) | **GET** /pet/findByTags | Finds Pets by tags
 *PetApi* | [**get_pet_by_id**](docs/PetApi.md#get_pet_by_id) | **GET** /pet/{petId} | Find pet by ID
 *PetApi* | [**get_pet_by_id_streaming**](docs/PetApi.md#get_pet_by_id_streaming) | **GET** /pet/{petId}?streaming | Find pet by ID (streaming)
+*PetApi* | [**test_header**](docs/PetApi.md#test_header) | **GET** /pet_header_test | Header test
 *PetApi* | [**update_pet**](docs/PetApi.md#update_pet) | **PUT** /pet | Update an existing pet
 *PetApi* | [**update_pet_with_form**](docs/PetApi.md#update_pet_with_form) | **POST** /pet/{petId} | Updates a pet in the store with form data
 *PetApi* | [**upload_file**](docs/PetApi.md#upload_file) | **POST** /pet/{petId}/uploadImage | uploads an image

samples/client/petstore/R-httr2/docs/PetApi.md

@@ -10,6 +10,7 @@ Method | HTTP request | Description
 [**find_pets_by_tags**](PetApi.md#find_pets_by_tags) | **GET** /pet/findByTags | Finds Pets by tags
 [**get_pet_by_id**](PetApi.md#get_pet_by_id) | **GET** /pet/{petId} | Find pet by ID
 [**get_pet_by_id_streaming**](PetApi.md#get_pet_by_id_streaming) | **GET** /pet/{petId}?streaming | Find pet by ID (streaming)
+[**test_header**](PetApi.md#test_header) | **GET** /pet_header_test | Header test
 [**update_pet**](PetApi.md#update_pet) | **PUT** /pet | Update an existing pet
 [**update_pet_with_form**](PetApi.md#update_pet_with_form) | **POST** /pet/{petId} | Updates a pet in the store with form data
 [**upload_file**](PetApi.md#upload_file) | **POST** /pet/{petId}/uploadImage | uploads an image
@@ -395,6 +396,72 @@ Name | Type | Description  | Notes
 | **400** | Invalid ID supplied |  -  |
 | **404** | Pet not found |  -  |
 
+# **test_header**
+> Pet test_header(header_test_int)
+
+Header test
+
+Header test
+
+### Example
+```R
+library(petstore)
+
+var_header_test_int <- 56 # integer | header test int
+
+#Header test
+api_instance <- PetApi$new()
+# Configure API key authorization: api_key
+api_instance$api_client$api_keys['api_key'] <- 'TODO_YOUR_API_KEY';
+result <- tryCatch(
+             # to save the result into a file, simply add the optional `data_file` parameter, e.g.
+             # api_instance$test_header(var_header_test_int, data_file = "result.txt"),
+             # this endpoint supports data streaming via a callback function using the optional `stream_callback` parameter, e.g.
+             # api_instance$test_header(var_header_test_int, stream_callback = function(x){ print(length(x)) }),
+             api_instance$test_header(var_header_test_int),
+             ApiException = function(ex) ex
+          )
+# In case of error, print the error object
+if (!is.null(result$ApiException)) {
+  dput(result$ApiException)
+  # error object
+  dput(result$ApiException$error_object)
+} else {
+  # deserialized response object
+  dput(result$content)
+  # response headers
+  dput(result$response$headers)
+  # response status code
+  dput(result$response$status_code)
+}
+```
+
+### Parameters
+
+Name | Type | Description  | Notes
+------------- | ------------- | ------------- | -------------
+ **header_test_int** | **integer**| header test int | 
+
+### Return type
+
+[**Pet**](Pet.md)
+
+### Authorization
+
+[api_key](../README.md#api_key)
+
+### HTTP request headers
+
+ - **Content-Type**: Not defined
+ - **Accept**: application/xml, application/json
+
+### HTTP response details
+| Status code | Description | Response headers |
+|-------------|-------------|------------------|
+| **200** | successful operation |  -  |
+| **400** | Invalid ID supplied |  -  |
+| **404** | Pet not found |  -  |
+
 # **update_pet**
 > Pet update_pet(pet)
 

samples/client/petstore/R-httr2/tests/testthat/test_petstore.R

@@ -101,6 +101,21 @@ test_that("get_pet_by_id_streaming", {
             )
 })
 
+test_that("Test header parameters", {
+  # test exception 
+  result <- tryCatch(pet_api$test_header(45345), 
+          ApiException = function(ex) ex
+  )
+
+  expect_true(!is.null(result))
+  expect_true(!is.null(result$ApiException))
+  expect_equal(result$ApiException$status, 404)
+  # test error object `ApiResponse`
+  #expect_equal(result$ApiException$error_object$toString(), "{\"code\":404,\"type\":\"unknown\",\"message\":\"null for uri: http://pet\n  x[1]: store.swagger.io/v2/pet_header_test\"}")
+  expect_equal(result$ApiException$error_object$code, 404)
+})
+
+
 test_that("Test GetPetById exception", {
   # test exception
   result <- tryCatch(pet_api$get_pet_by_id(98765), # petId not exist

samples/client/petstore/R/R/pet_api.R

@@ -171,6 +171,38 @@
 #' }
 #' }
 #'
+#' \strong{ TestHeader } \emph{ Header test }
+#' Header test
+#'
+#' \itemize{
+#' \item \emph{ @param } header_test_int integer
+#' \item \emph{ @returnType } \link{Pet} \cr
+#'
+#' \item On encountering errors, an error of subclass ApiException will be thrown.
+#'
+#' \item status code : 200 | successful operation
+#'
+#' \item return type : Pet
+#' \item response headers :
+#'
+#' \tabular{ll}{
+#' }
+#' \item status code : 400 | Invalid ID supplied
+#'
+#'
+#' \item response headers :
+#'
+#' \tabular{ll}{
+#' }
+#' \item status code : 404 | Pet not found
+#'
+#'
+#' \item response headers :
+#'
+#' \tabular{ll}{
+#' }
+#' }
+#'
 #' \strong{ UpdatePet } \emph{ Update an existing pet }
 #' 
 #'
@@ -424,6 +456,34 @@
 #' }
 #'
 #'
+#' ####################  TestHeader  ####################
+#'
+#' library(petstore)
+#' var.header_test_int <- 56 # integer | header test int
+#'
+#' #Header test
+#' api.instance <- PetApi$new()
+#'
+#' #Configure API key authorization: api_key
+#' api.instance$api_client$api_keys['api_key'] <- 'TODO_YOUR_API_KEY';
+#'
+#'result <- tryCatch(
+#'             api.instance$TestHeader(var.header_test_int),
+#'             ApiException = function(ex) ex
+#'          )
+#' # In case of error, print the error object
+#' if(!is.null(result$ApiException)) {
+#'   cat(result$ApiException$toString())
+#' } else {
+#' # deserialized response object
+#' response.object <- result$content
+#' # response headers
+#' response.headers <- result$response$headers
+#' # response status code
+#' response.status.code <- result$response$status_code
+#' }
+#'
+#'
 #' ####################  UpdatePet  ####################
 #'
 #' library(petstore)
@@ -1197,6 +1257,127 @@ PetApi <- R6::R6Class(
                      ApiException = ApiException$new(http_response = local_var_resp))
       }
     },
+    #' Header test
+    #'
+    #' @description
+    #' Header test
+    #'
+    #' @param header_test_int header test int
+    #' @param stream_callback (optional) callback function to process the data stream
+    #' @param data_file (optional) name of the data file to save the result
+    #' @param ... Other optional arguments
+    #' @return Pet
+    #' @export
+    TestHeader = function(header_test_int, stream_callback = NULL, data_file = NULL, ...) {
+      local_var_response <- self$TestHeaderWithHttpInfo(header_test_int, stream_callback = stream_callback, data_file = data_file, ...)
+      if (typeof(stream_callback) == "closure") { # return void if streaming is enabled
+        return(invisible(NULL))
+      }
+
+      if (local_var_response$status_code >= 200 && local_var_response$status_code <= 299) {
+        local_var_response$content
+      } else if (local_var_response$status_code >= 300 && local_var_response$status_code <= 399) {
+        local_var_response
+      } else if (local_var_response$status_code >= 400 && local_var_response$status_code <= 499) {
+        local_var_response
+      } else if (local_var_response$status_code >= 500 && local_var_response$status_code <= 599) {
+        local_var_response
+      }
+    },
+    #' Header test
+    #'
+    #' @description
+    #' Header test
+    #'
+    #' @param header_test_int header test int
+    #' @param stream_callback (optional) callback function to process the data stream
+    #' @param data_file (optional) name of the data file to save the result
+    #' @param ... Other optional arguments
+    #' @return API response (Pet) with additional information such as HTTP status code, headers
+    #' @export
+    TestHeaderWithHttpInfo = function(header_test_int, stream_callback = NULL, data_file = NULL, ...) {
+      args <- list(...)
+      query_params <- list()
+      header_params <- c()
+
+      if (missing(`header_test_int`)) {
+        rlang::abort(message = "Missing required parameter `header_test_int`.",
+                     .subclass = "ApiException",
+                     ApiException = ApiException$new(status = 0,
+                                                     reason = "Missing required parameter `header_test_int`."))
+      }
+
+      header_params["header_test_int"] <- `header_test_int`
+
+      local_var_body <- NULL
+      local_var_url_path <- "/pet_header_test"
+      # API key authentication
+      if ("api_key" %in% names(self$api_client$api_keys) && nchar(self$api_client$api_keys["api_key"]) > 0) {
+        header_params["api_key"] <- paste(unlist(self$api_client$api_keys["api_key"]), collapse = "")
+      }
+
+      # The Accept request HTTP header
+      local_var_accepts = list("application/xml", "application/json")
+
+      # The Content-Type representation header
+      local_var_content_types = list()
+
+      local_var_resp <- self$api_client$CallApi(url = paste0(self$api_client$base_path, local_var_url_path),
+                                 method = "GET",
+                                 query_params = query_params,
+                                 header_params = header_params,
+                                 accepts = local_var_accepts,
+                                 content_types = local_var_content_types,
+                                 body = local_var_body,
+                                 stream_callback = stream_callback,
+                                 ...)
+
+      if (typeof(stream_callback) == "closure") { # return void if streaming is enabled
+        return(invisible(NULL))
+      }
+
+      if (local_var_resp$status_code >= 200 && local_var_resp$status_code <= 299) {
+        # save response in a file
+        if (!is.null(data_file)) {
+            write(local_var_resp$response, data_file)
+        }
+
+        deserialized_resp_obj <- tryCatch(
+          self$api_client$deserialize(local_var_resp$response, "Pet", loadNamespace("petstore")),
+          error = function(e) {
+             rlang::abort(message = "Failed to deserialize response",
+                          .subclass = "ApiException",
+                          ApiException = ApiException$new(http_response = local_var_resp))
+          }
+        )
+        local_var_resp$content <- deserialized_resp_obj
+        local_var_resp
+      } else if (local_var_resp$status_code >= 300 && local_var_resp$status_code <= 399) {
+        local_var_error_msg <- local_var_resp$response
+        if (local_var_error_msg == "") {
+          local_var_error_msg <- paste("Server returned ", local_var_resp$status_code, " response status code.")
+        }
+        rlang::abort(message = local_var_error_msg,
+                     .subclass = "ApiException",
+                     ApiException = ApiException$new(http_response = local_var_resp))
+      } else if (local_var_resp$status_code >= 400 && local_var_resp$status_code <= 499) {
+        local_var_error_msg <- local_var_resp$response
+        if (local_var_error_msg == "") {
+          local_var_error_msg <- "Api client exception encountered."
+        }
+        rlang::abort(message = local_var_error_msg,
+                     .subclass = "ApiException",
+                     ApiException = ApiException$new(http_response = local_var_resp))
+      } else if (local_var_resp$status_code >= 500 && local_var_resp$status_code <= 599) {
+        local_var_error_msg <- local_var_resp$response
+        if (local_var_error_msg == "") {
+          local_var_error_msg <- "Api server exception encountered."
+        }
+        rlang::abort(message = error_msg,
+                     .subclass = "ApiException",
+                     ApiException = ApiException$new(http_response = local_var_resp))
+      }
+    },
     #' Update an existing pet
     #'
     #' @description

samples/client/petstore/R/README.md

@@ -68,6 +68,7 @@ Class | Method | HTTP request | Description
 *PetApi* | [**FindPetsByTags**](docs/PetApi.md#FindPetsByTags) | **GET** /pet/findByTags | Finds Pets by tags
 *PetApi* | [**GetPetById**](docs/PetApi.md#GetPetById) | **GET** /pet/{petId} | Find pet by ID
 *PetApi* | [**GetPetByIdStreaming**](docs/PetApi.md#GetPetByIdStreaming) | **GET** /pet/{petId}?streaming | Find pet by ID (streaming)
+*PetApi* | [**TestHeader**](docs/PetApi.md#TestHeader) | **GET** /pet_header_test | Header test
 *PetApi* | [**UpdatePet**](docs/PetApi.md#UpdatePet) | **PUT** /pet | Update an existing pet
 *PetApi* | [**UpdatePetWithForm**](docs/PetApi.md#UpdatePetWithForm) | **POST** /pet/{petId} | Updates a pet in the store with form data
 *PetApi* | [**UploadFile**](docs/PetApi.md#UploadFile) | **POST** /pet/{petId}/uploadImage | uploads an image

samples/client/petstore/R/docs/PetApi.md

@@ -10,6 +10,7 @@ Method | HTTP request | Description
 [**FindPetsByTags**](PetApi.md#FindPetsByTags) | **GET** /pet/findByTags | Finds Pets by tags
 [**GetPetById**](PetApi.md#GetPetById) | **GET** /pet/{petId} | Find pet by ID
 [**GetPetByIdStreaming**](PetApi.md#GetPetByIdStreaming) | **GET** /pet/{petId}?streaming | Find pet by ID (streaming)
+[**TestHeader**](PetApi.md#TestHeader) | **GET** /pet_header_test | Header test
 [**UpdatePet**](PetApi.md#UpdatePet) | **PUT** /pet | Update an existing pet
 [**UpdatePetWithForm**](PetApi.md#UpdatePetWithForm) | **POST** /pet/{petId} | Updates a pet in the store with form data
 [**UploadFile**](PetApi.md#UploadFile) | **POST** /pet/{petId}/uploadImage | uploads an image
@@ -395,6 +396,72 @@ Name | Type | Description  | Notes
 | **400** | Invalid ID supplied |  -  |
 | **404** | Pet not found |  -  |
 
+# **TestHeader**
+> Pet TestHeader(header_test_int)
+
+Header test
+
+Header test
+
+### Example
+```R
+library(petstore)
+
+var_header_test_int <- 56 # integer | header test int
+
+#Header test
+api_instance <- PetApi$new()
+# Configure API key authorization: api_key
+api_instance$api_client$api_keys['api_key'] <- 'TODO_YOUR_API_KEY';
+result <- tryCatch(
+             # to save the result into a file, simply add the optional `data_file` parameter, e.g.
+             # api_instance$TestHeader(var_header_test_int, data_file = "result.txt"),
+             # this endpoint supports data streaming via a callback function using the optional `stream_callback` parameter, e.g.
+             # api_instance$TestHeader(var_header_test_int, stream_callback = function(x){ print(length(x)) }),
+             api_instance$TestHeader(var_header_test_int),
+             ApiException = function(ex) ex
+          )
+# In case of error, print the error object
+if (!is.null(result$ApiException)) {
+  dput(result$ApiException)
+  # error object
+  dput(result$ApiException$error_object)
+} else {
+  # deserialized response object
+  dput(result$content)
+  # response headers
+  dput(result$response$headers)
+  # response status code
+  dput(result$response$status_code)
+}
+```
+
+### Parameters
+
+Name | Type | Description  | Notes
+------------- | ------------- | ------------- | -------------
+ **header_test_int** | **integer**| header test int | 
+
+### Return type
+
+[**Pet**](Pet.md)
+
+### Authorization
+
+[api_key](../README.md#api_key)
+
+### HTTP request headers
+
+ - **Content-Type**: Not defined
+ - **Accept**: application/xml, application/json
+
+### HTTP response details
+| Status code | Description | Response headers |
+|-------------|-------------|------------------|
+| **200** | successful operation |  -  |
+| **400** | Invalid ID supplied |  -  |
+| **404** | Pet not found |  -  |
+
 # **UpdatePet**
 > Pet UpdatePet(pet)
 

samples/client/petstore/R/tests/testthat/test_petstore.R

@@ -107,6 +107,20 @@ test_that("GetPetByIdStreaming", {
             )
 })
 
+test_that("Test header parameters", {
+  # test exception 
+  result <- tryCatch(pet_api$TestHeader(45345), 
+          ApiException = function(ex) ex
+  )
+
+  expect_true(!is.null(result))
+  expect_true(!is.null(result$ApiException))
+  expect_equal(result$ApiException$status, 404)
+  # test error object `ApiResponse`
+  #expect_equal(result$ApiException$error_object$toString(), "{\"code\":404,\"type\":\"unknown\",\"message\":\"null for uri: http://pet\n  x[1]: store.swagger.io/v2/pet_header_test\"}")
+  expect_equal(result$ApiException$error_object$code, 404)
+})
+
 test_that("Test GetPetById exception", {
   # test exception 
   result <- tryCatch(pet_api$GetPetById(98765), # petId not exist