[R] add streaming support (#12821)

* add streaming option to r client * support callback function to process data stream * add stream test, minor bug fixes * fix api client * return void earlier if streaming, add tests
2022-07-11 00:19:07 +08:00
parent 84ac06abdc
commit 20420e5e14
11 changed files with 488 additions and 114 deletions
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/RClientCodegen.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/RClientCodegen.java
@@ -224,11 +224,9 @@ public class RClientCodegen extends DefaultCodegen implements CodegenConfig {
        additionalProperties.put(CodegenConstants.PACKAGE_NAME, packageName);
        additionalProperties.put(CodegenConstants.PACKAGE_VERSION, packageVersion);
        additionalProperties.put(CodegenConstants.EXCEPTION_ON_FAILURE, returnExceptionOnFailure);
-
        additionalProperties.put(USE_DEFAULT_EXCEPTION, this.useDefaultExceptionHandling);
        additionalProperties.put(USE_RLANG_EXCEPTION, this.useRlangExceptionHandling);

-
        additionalProperties.put("apiDocPath", apiDocPath);
        additionalProperties.put("modelDocPath", modelDocPath);

--- a/modules/openapi-generator/src/main/resources/r/api.mustache
+++ b/modules/openapi-generator/src/main/resources/r/api.mustache
@@ -177,14 +177,23 @@
    {{#optionalParams}}
    #' @param {{{paramName}}} (optional) {{{description}}}{{#defaultValue}} (default value: {{{.}}}){{/defaultValue}}
    {{/optionalParams}}
+    {{#vendorExtensions.x-streaming}}
+    #' @param stream_callback (optional) callback function to process the data stream
+    {{/vendorExtensions.x-streaming}}
    {{#returnType}}
    #' @param data_file (optional) name of the data file to save the result
    {{/returnType}}
    #' @param ... Other optional arguments
    #' @return {{{returnType}}}{{^returnType}}void{{/returnType}}
    #' @export
-    {{{operationId}}} = function({{#requiredParams}}{{paramName}}, {{/requiredParams}}{{#optionalParams}}{{paramName}}={{^defaultValue}}NULL{{/defaultValue}}{{{defaultValue}}}, {{/optionalParams}}{{#returnType}}data_file=NULL, {{/returnType}}...) {
-      api_response <- self${{{operationId}}}WithHttpInfo({{#allParams}}{{paramName}}, {{/allParams}}{{#returnType}}data_file = data_file, {{/returnType}}...)
+    {{{operationId}}} = function({{#requiredParams}}{{paramName}}, {{/requiredParams}}{{#optionalParams}}{{paramName}}={{^defaultValue}}NULL{{/defaultValue}}{{{defaultValue}}}, {{/optionalParams}}{{#vendorExtensions.x-streaming}}stream_callback=NULL, {{/vendorExtensions.x-streaming}}{{#returnType}}data_file=NULL, {{/returnType}}...) {
+      api_response <- self${{{operationId}}}WithHttpInfo({{#allParams}}{{paramName}}, {{/allParams}}{{#vendorExtensions.x-streaming}}stream_callback = stream_callback, {{/vendorExtensions.x-streaming}}{{#returnType}}data_file = data_file, {{/returnType}}...)
+      {{#vendorExtensions.x-streaming}}
+      if (typeof(stream_callback) == "closure") { # return void if streaming is enabled
+        return(invisible(NULL))
+      }
+
+      {{/vendorExtensions.x-streaming}}
      resp <- api_response$response
      if (httr::status_code(resp) >= 200 && httr::status_code(resp) <= 299) {
        api_response$content
@@ -207,13 +216,16 @@
    {{#optionalParams}}
    #' @param {{{paramName}}} (optional) {{{description}}}{{#defaultValue}} (default value: {{{.}}}){{/defaultValue}}
    {{/optionalParams}}
+    {{#vendorExtensions.x-streaming}}
+    #' @param stream_callback (optional) callback function to process the data stream
+    {{/vendorExtensions.x-streaming}}
    {{#returnType}}
    #' @param data_file (optional) name of the data file to save the result
    {{/returnType}}
    #' @param ... Other optional arguments
    #' @return API response ({{{returnType}}}{{^returnType}}void{{/returnType}}) with additional information such as HTTP status code, headers
    #' @export
-    {{{operationId}}}WithHttpInfo = function({{#requiredParams}}{{paramName}}, {{/requiredParams}}{{#optionalParams}}{{paramName}}={{^defaultValue}}NULL{{/defaultValue}}{{{defaultValue}}}, {{/optionalParams}}{{#returnType}}data_file = NULL, {{/returnType}}...) {
+    {{{operationId}}}WithHttpInfo = function({{#requiredParams}}{{paramName}}, {{/requiredParams}}{{#optionalParams}}{{paramName}}={{^defaultValue}}NULL{{/defaultValue}}{{{defaultValue}}}, {{/optionalParams}}{{#vendorExtensions.x-streaming}}stream_callback=NULL, {{/vendorExtensions.x-streaming}}{{#returnType}}data_file = NULL, {{/returnType}}...) {
      args <- list(...)
      query_params <- list()
      header_params <- c()
@@ -311,8 +323,17 @@
                                 query_params = query_params,
                                 header_params = header_params,
                                 body = body,
+                                 {{#vendorExtensions.x-streaming}}
+                                 stream_callback = stream_callback,
+                                 {{/vendorExtensions.x-streaming}}
                                 ...)

+      {{#vendorExtensions.x-streaming}}
+      if (typeof(stream_callback) == "closure") { # return void if streaming is enabled
+        return(invisible(NULL))
+      }
+
+      {{/vendorExtensions.x-streaming}}
      if (httr::status_code(resp) >= 200 && httr::status_code(resp) <= 299) {
        {{#returnType}}
        {{#isPrimitiveType}}
--- a/modules/openapi-generator/src/main/resources/r/api_client.mustache
+++ b/modules/openapi-generator/src/main/resources/r/api_client.mustache
@@ -128,9 +128,9 @@ ApiClient  <- R6::R6Class(
    #' @param ... Other optional arguments.
    #' @return HTTP response
    #' @export
-    CallApi = function(url, method, query_params, header_params, body, ...) {
+    CallApi = function(url, method, query_params, header_params, body, stream_callback = NULL, ...) {

-      resp <- self$Execute(url, method, query_params, header_params, body, ...)
+      resp <- self$Execute(url, method, query_params, header_params, body, stream_callback = stream_callback, ...)
      status_code <- httr::status_code(resp)

      if (is.null(self$max_retry_attempts)) {
@@ -142,7 +142,7 @@ ApiClient  <- R6::R6Class(
        for (i in 1 : self$max_retry_attempts) {
          if (status_code %in% self$retry_status_codes) {
            Sys.sleep((2 ^ i) + stats::runif(n = 1, min = 0, max = 1))
-            resp <- self$Execute(url, method, query_params, header_params, body, ...)
+            resp <- self$Execute(url, method, query_params, header_params, body, stream_callback = stream_callback, ...)
            status_code <- httr::status_code(resp)
          } else {
            break;
@@ -162,10 +162,11 @@ ApiClient  <- R6::R6Class(
    #' @param query_params The query parameters.
    #' @param header_params The header parameters.
    #' @param body The HTTP request body.
+    #' @param stream_callback callback function to process data stream
    #' @param ... Other optional arguments.
    #' @return HTTP response
    #' @export
-    Execute = function(url, method, query_params, header_params, body, ...) {
+    Execute = function(url, method, query_params, header_params, body, stream_callback = NULL, ...) {
      headers <- httr::add_headers(c(header_params, self$default_headers))

      {{! Adding timeout that can be set at the apiClient object level}}
@@ -175,17 +176,41 @@ ApiClient  <- R6::R6Class(
      }

      if (method == "GET") {
-        httr::GET(url, query = query_params, headers, http_timeout, httr::user_agent(self$`user_agent`), ...)
+        if (typeof(stream_callback) == "closure") {
+          httr::GET(url, query = query_params, headers, http_timeout, httr::user_agent(self$`user_agent`), write_stream(stream_callback), ...)
+        } else {
+          httr::GET(url, query = query_params, headers, http_timeout, httr::user_agent(self$`user_agent`), ...)
+        }
      } else if (method == "POST") {
-        httr::POST(url, query = query_params, headers, body = body, httr::content_type("application/json"), http_timeout, httr::user_agent(self$`user_agent`), ...)
+        if (typeof(stream_callback) == "closure") {
+          httr::POST(url, query = query_params, headers, body = body, httr::content_type("application/json"), http_timeout, httr::user_agent(self$`user_agent`), write_stream(stream_callback), ...)
+        } else {
+          httr::POST(url, query = query_params, headers, body = body, httr::content_type("application/json"), http_timeout, httr::user_agent(self$`user_agent`), ...)
+        }
      } else if (method == "PUT") {
-        httr::PUT(url, query = query_params, headers, body = body, httr::content_type("application/json"), http_timeout, http_timeout, httr::user_agent(self$`user_agent`), ...)
+        if (typeof(stream_callback) == "closure") {
+          httr::PUT(url, query = query_params, headers, body = body, httr::content_type("application/json"), http_timeout, http_timeout, httr::user_agent(self$`user_agent`), write_stream(stream_callback), ...)
+        } else {
+          httr::PUT(url, query = query_params, headers, body = body, httr::content_type("application/json"), http_timeout, http_timeout, httr::user_agent(self$`user_agent`), ...)
+        }
      } else if (method == "PATCH") {
-        httr::PATCH(url, query = query_params, headers, body = body, httr::content_type("application/json"), http_timeout, http_timeout, httr::user_agent(self$`user_agent`), ...)
+        if (typeof(stream_callback) == "closure") {
+          httr::PATCH(url, query = query_params, headers, body = body, httr::content_type("application/json"), http_timeout, http_timeout, httr::user_agent(self$`user_agent`), write_stream(stream_callback), ...)
+        } else {
+          httr::PATCH(url, query = query_params, headers, body = body, httr::content_type("application/json"), http_timeout, http_timeout, httr::user_agent(self$`user_agent`), ...)
+        }
      } else if (method == "HEAD") {
-        httr::HEAD(url, query = query_params, headers, http_timeout, http_timeout, httr::user_agent(self$`user_agent`), ...)
+        if (typeof(stream_callback) == "closure") {
+          httr::HEAD(url, query = query_params, headers, http_timeout, http_timeout, httr::user_agent(self$`user_agent`), write_stream(stream_callback), ...)
+        } else {
+          httr::HEAD(url, query = query_params, headers, http_timeout, http_timeout, httr::user_agent(self$`user_agent`), ...)
+        }
      } else if (method == "DELETE") {
-        httr::DELETE(url, query = query_params, headers, http_timeout, http_timeout, httr::user_agent(self$`user_agent`), ...)
+        if (typeof(stream_callback) == "closure") {
+          httr::DELETE(url, query = query_params, headers, http_timeout, http_timeout, httr::user_agent(self$`user_agent`), write_stream(stream_callback), ...)
+        } else {
+          httr::DELETE(url, query = query_params, headers, http_timeout, http_timeout, httr::user_agent(self$`user_agent`), ...)
+        }
      } else {
        err_msg <- "Http method must be `GET`, `HEAD`, `OPTIONS`, `POST`, `PATCH`, `PUT` or `DELETE`."
        {{#useDefaultExceptionHandling}}
--- a/modules/openapi-generator/src/main/resources/r/api_doc.mustache
+++ b/modules/openapi-generator/src/main/resources/r/api_doc.mustache
@@ -53,7 +53,7 @@ result <- tryCatch(
             # to save the result into a file, simply add the optional `data_file` parameter, e.g.
             # api_instance${{{operationId}}}({{#requiredParams}}var_{{{paramName}}}{{^-last}}, {{/-last}}{{/requiredParams}}{{#optionalParams}}{{#-first}}{{#requiredParams.0}}, {{/requiredParams.0}}{{/-first}}{{{paramName}}} = var_{{{paramName}}}{{^-last}}, {{/-last}}{{/optionalParams}}{{#allParams}}{{#-first}}, {{/-first}}{{/allParams}}data_file = "result.txt"),
             {{/returnType}}
-             api_instance${{{operationId}}}({{#requiredParams}}var_{{{paramName}}}{{^-last}}, {{/-last}}{{/requiredParams}}{{#optionalParams}}{{#-first}}{{#requiredParams.0}}, {{/requiredParams.0}}{{/-first}}{{{paramName}}} = var_{{{paramName}}}{{^-last}}, {{/-last}}{{/optionalParams}}),
+             api_instance${{{operationId}}}({{#requiredParams}}var_{{{paramName}}}{{^-last}}, {{/-last}}{{/requiredParams}}{{#optionalParams}}{{#-first}}{{#requiredParams.0}}, {{/requiredParams.0}}{{/-first}}{{{paramName}}} = var_{{{paramName}}}{{^-last}}, {{/-last}}{{/optionalParams}}{{#vendorExtensions.x-streaming}}, stream_callback = function(x){ print(length(x)) }{{/vendorExtensions.x-streaming}}),
             ApiException = function(ex) ex
          )
 # In case of error, print the error object
--- a/modules/openapi-generator/src/test/resources/3_0/r/petstore.yaml
+++ b/modules/openapi-generator/src/test/resources/3_0/r/petstore.yaml
@@ -185,6 +185,38 @@ paths:
          description: Pet not found
      security:
        - api_key: []
+  '/pet/{petId}?streaming':
+    get:
+      tags:
+        - pet
+      summary: Find pet by ID (streaming)
+      description: Returns a single pet
+      operationId: getPetByIdStreaming
+      x-streaming: true
+      parameters:
+        - name: petId
+          in: path
+          description: ID of pet to return
+          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: []
    post:
      tags:
        - pet
--- a/samples/client/petstore/R/R/api_client.R
+++ b/samples/client/petstore/R/R/api_client.R
@@ -133,9 +133,9 @@ ApiClient  <- R6::R6Class(
    #' @param ... Other optional arguments.
    #' @return HTTP response
    #' @export
-    CallApi = function(url, method, query_params, header_params, body, ...) {
+    CallApi = function(url, method, query_params, header_params, body, stream_callback = NULL, ...) {

-      resp <- self$Execute(url, method, query_params, header_params, body, ...)
+      resp <- self$Execute(url, method, query_params, header_params, body, stream_callback = stream_callback, ...)
      status_code <- httr::status_code(resp)

      if (is.null(self$max_retry_attempts)) {
@@ -147,7 +147,7 @@ ApiClient  <- R6::R6Class(
        for (i in 1 : self$max_retry_attempts) {
          if (status_code %in% self$retry_status_codes) {
            Sys.sleep((2 ^ i) + stats::runif(n = 1, min = 0, max = 1))
-            resp <- self$Execute(url, method, query_params, header_params, body, ...)
+            resp <- self$Execute(url, method, query_params, header_params, body, stream_callback = stream_callback, ...)
            status_code <- httr::status_code(resp)
          } else {
            break;
@@ -167,10 +167,11 @@ ApiClient  <- R6::R6Class(
    #' @param query_params The query parameters.
    #' @param header_params The header parameters.
    #' @param body The HTTP request body.
+    #' @param stream_callback callback function to process data stream
    #' @param ... Other optional arguments.
    #' @return HTTP response
    #' @export
-    Execute = function(url, method, query_params, header_params, body, ...) {
+    Execute = function(url, method, query_params, header_params, body, stream_callback = NULL, ...) {
      headers <- httr::add_headers(c(header_params, self$default_headers))

      http_timeout <- NULL
@@ -179,17 +180,41 @@ ApiClient  <- R6::R6Class(
      }

      if (method == "GET") {
-        httr::GET(url, query = query_params, headers, http_timeout, httr::user_agent(self$`user_agent`), ...)
+        if (typeof(stream_callback) == "closure") {
+          httr::GET(url, query = query_params, headers, http_timeout, httr::user_agent(self$`user_agent`), write_stream(stream_callback), ...)
+        } else {
+          httr::GET(url, query = query_params, headers, http_timeout, httr::user_agent(self$`user_agent`), ...)
+        }
      } else if (method == "POST") {
-        httr::POST(url, query = query_params, headers, body = body, httr::content_type("application/json"), http_timeout, httr::user_agent(self$`user_agent`), ...)
+        if (typeof(stream_callback) == "closure") {
+          httr::POST(url, query = query_params, headers, body = body, httr::content_type("application/json"), http_timeout, httr::user_agent(self$`user_agent`), write_stream(stream_callback), ...)
+        } else {
+          httr::POST(url, query = query_params, headers, body = body, httr::content_type("application/json"), http_timeout, httr::user_agent(self$`user_agent`), ...)
+        }
      } else if (method == "PUT") {
-        httr::PUT(url, query = query_params, headers, body = body, httr::content_type("application/json"), http_timeout, http_timeout, httr::user_agent(self$`user_agent`), ...)
+        if (typeof(stream_callback) == "closure") {
+          httr::PUT(url, query = query_params, headers, body = body, httr::content_type("application/json"), http_timeout, http_timeout, httr::user_agent(self$`user_agent`), write_stream(stream_callback), ...)
+        } else {
+          httr::PUT(url, query = query_params, headers, body = body, httr::content_type("application/json"), http_timeout, http_timeout, httr::user_agent(self$`user_agent`), ...)
+        }
      } else if (method == "PATCH") {
-        httr::PATCH(url, query = query_params, headers, body = body, httr::content_type("application/json"), http_timeout, http_timeout, httr::user_agent(self$`user_agent`), ...)
+        if (typeof(stream_callback) == "closure") {
+          httr::PATCH(url, query = query_params, headers, body = body, httr::content_type("application/json"), http_timeout, http_timeout, httr::user_agent(self$`user_agent`), write_stream(stream_callback), ...)
+        } else {
+          httr::PATCH(url, query = query_params, headers, body = body, httr::content_type("application/json"), http_timeout, http_timeout, httr::user_agent(self$`user_agent`), ...)
+        }
      } else if (method == "HEAD") {
-        httr::HEAD(url, query = query_params, headers, http_timeout, http_timeout, httr::user_agent(self$`user_agent`), ...)
+        if (typeof(stream_callback) == "closure") {
+          httr::HEAD(url, query = query_params, headers, http_timeout, http_timeout, httr::user_agent(self$`user_agent`), write_stream(stream_callback), ...)
+        } else {
+          httr::HEAD(url, query = query_params, headers, http_timeout, http_timeout, httr::user_agent(self$`user_agent`), ...)
+        }
      } else if (method == "DELETE") {
-        httr::DELETE(url, query = query_params, headers, http_timeout, http_timeout, httr::user_agent(self$`user_agent`), ...)
+        if (typeof(stream_callback) == "closure") {
+          httr::DELETE(url, query = query_params, headers, http_timeout, http_timeout, httr::user_agent(self$`user_agent`), write_stream(stream_callback), ...)
+        } else {
+          httr::DELETE(url, query = query_params, headers, http_timeout, http_timeout, httr::user_agent(self$`user_agent`), ...)
+        }
      } else {
        err_msg <- "Http method must be `GET`, `HEAD`, `OPTIONS`, `POST`, `PATCH`, `PUT` or `DELETE`."
        rlang::abort(message = err_msg, .subclass = "ApiException", ApiException = ApiException$new(status = 0, reason = err_msg))
--- a/samples/client/petstore/R/R/pet_api.R
+++ b/samples/client/petstore/R/R/pet_api.R
@@ -139,6 +139,38 @@
 #' }
 #' }
 #'
+#' \strong{ GetPetByIdStreaming } \emph{ Find pet by ID (streaming) }
+#' Returns a single pet
+#'
+#' \itemize{
+#' \item \emph{ @param } pet_id integer
+#' \item \emph{ @returnType } \link{Pet} \cr
+#'
+#' \item On encountering errors, an error of subclass ApiException will be thrown.
+#'
+#' \item status code : 200 | successful operation
+#'
+#' \item return type : Pet 
+#' \item response headers :
+#'
+#' \tabular{ll}{
+#' }
+#' \item status code : 400 | Invalid ID supplied
+#'
+#'
+#' \item response headers :
+#'
+#' \tabular{ll}{
+#' }
+#' \item status code : 404 | Pet not found
+#'
+#'
+#' \item response headers :
+#'
+#' \tabular{ll}{
+#' }
+#' }
+#'
 #' \strong{ UpdatePet } \emph{ Update an existing pet }
 #' 
 #'
@@ -361,6 +393,34 @@
 #' }
 #'
 #'
+#' ####################  GetPetByIdStreaming  ####################
+#'
+#' library(petstore)
+#' var.pet_id <- 56 # integer | ID of pet to return
+#'
+#' #Find pet by ID (streaming)
+#' api.instance <- PetApi$new()
+#'
+#' #Configure API key authorization: api_key
+#' api.instance$api_client$api_keys['api_key'] <- 'TODO_YOUR_API_KEY';
+#'
+#'result <- tryCatch(
+#'             api.instance$GetPetByIdStreaming(var.pet_id),
+#'             ApiException = function(ex) ex
+#'          )
+#' # In case of error, print the error object
+#' if(!is.null(result$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)
@@ -606,7 +666,7 @@ PetApi <- R6::R6Class(
      }

      body <- NULL
-      url_path <- "/pet/{petId}"
+      url_path <- "/pet/{petId}?streaming"
      if (!missing(`pet_id`)) {
        url_path <- gsub(paste0("\\{", "petId", "\\}"), URLencode(as.character(`pet_id`), reserved = TRUE), url_path)
      }
@@ -910,6 +970,110 @@ PetApi <- R6::R6Class(
        rlang::abort(message = error_msg, .subclass = "ApiException", ApiException = ApiException$new(http_response = resp))
      }
    },
+    #' Find pet by ID (streaming)
+    #'
+    #' @description
+    #' Find pet by ID (streaming)
+    #'
+    #' @param pet_id ID of pet to return
+    #' @param stream_callback (optional) callback function to process the data stream
+    #' @param data_file (optional) name of the data file to save the result
+    #' @param ... Other optional arguments
+    #' @return Pet
+    #' @export
+    GetPetByIdStreaming = function(pet_id, stream_callback=NULL, data_file=NULL, ...) {
+      api_response <- self$GetPetByIdStreamingWithHttpInfo(pet_id, stream_callback = stream_callback, data_file = data_file, ...)
+      if (typeof(stream_callback) == "closure") { # return void if streaming is enabled
+        return(invisible(NULL))
+      }
+
+      resp <- api_response$response
+      if (httr::status_code(resp) >= 200 && httr::status_code(resp) <= 299) {
+        api_response$content
+      } else if (httr::status_code(resp) >= 300 && httr::status_code(resp) <= 399) {
+        api_response
+      } else if (httr::status_code(resp) >= 400 && httr::status_code(resp) <= 499) {
+        api_response
+      } else if (httr::status_code(resp) >= 500 && httr::status_code(resp) <= 599) {
+        api_response
+      }
+    },
+    #' Find pet by ID (streaming)
+    #'
+    #' @description
+    #' Find pet by ID (streaming)
+    #'
+    #' @param pet_id ID of pet to return
+    #' @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
+    GetPetByIdStreamingWithHttpInfo = function(pet_id, stream_callback=NULL, data_file = NULL, ...) {
+      args <- list(...)
+      query_params <- list()
+      header_params <- c()
+
+      if (missing(`pet_id`)) {
+        rlang::abort(message = "Missing required parameter `pet_id`.", .subclass = "ApiException", ApiException = ApiException$new(status = 0, reason = "Missing required parameter `pet_id`."))
+      }
+
+      body <- NULL
+      url_path <- "/pet/{petId}?streaming"
+      if (!missing(`pet_id`)) {
+        url_path <- gsub(paste0("\\{", "petId", "\\}"), URLencode(as.character(`pet_id`), reserved = TRUE), url_path)
+      }
+
+      # API key authentication
+      if ("api_key" %in% names(self$api_client$api_keys) && nchar(self$api_client$api_keys["api_key"]) > 0) {
+        header_params["api_key"] <- paste(unlist(self$api_client$api_keys["api_key"]), collapse = "")
+      }
+
+      resp <- self$api_client$CallApi(url = paste0(self$api_client$base_path, url_path),
+                                 method = "GET",
+                                 query_params = query_params,
+                                 header_params = header_params,
+                                 body = body,
+                                 stream_callback = stream_callback,
+                                 ...)
+
+      if (typeof(stream_callback) == "closure") { # return void if streaming is enabled
+        return(invisible(NULL))
+      }
+
+      if (httr::status_code(resp) >= 200 && httr::status_code(resp) <= 299) {
+        # save response in a file
+        if (!is.null(data_file)) {
+            write(httr::content(resp, "text", encoding = "UTF-8", simplifyVector = FALSE), data_file)
+        }
+
+        deserialized_resp_obj <- tryCatch(
+          self$api_client$deserialize(resp, "Pet", loadNamespace("petstore")),
+          error = function(e) {
+             rlang::abort(message = "Failed to deserialize response", .subclass = "ApiException", ApiException = ApiException$new(http_response = resp))
+          }
+        )
+        ApiResponse$new(deserialized_resp_obj, resp)
+      } else if (httr::status_code(resp) >= 300 && httr::status_code(resp) <= 399) {
+        error_msg <- toString(content(resp))
+        if(error_msg == "") {
+          error_msg <- paste("Server returned ", httr::status_code(resp), " response status code.")
+        }
+        rlang::abort(message = error_msg, .subclass = "ApiException", ApiException = ApiException$new(http_response = resp))
+      } else if (httr::status_code(resp) >= 400 && httr::status_code(resp) <= 499) {
+        error_msg <- toString(content(resp))
+        if(error_msg == "") {
+          error_msg <- "Api client exception encountered."
+        }
+        rlang::abort(message = error_msg, .subclass = "ApiException", ApiException = ApiException$new(http_response = resp))
+      } else if (httr::status_code(resp) >= 500 && httr::status_code(resp) <= 599) {
+        error_msg <- toString(content(resp))
+        if(error_msg == "") {
+          error_msg <- "Api server exception encountered."
+        }
+        rlang::abort(message = error_msg, .subclass = "ApiException", ApiException = ApiException$new(http_response = resp))
+      }
+    },
    #' Update an existing pet
    #'
    #' @description
@@ -1051,7 +1215,7 @@ PetApi <- R6::R6Class(
        "status" = status
      )

-      url_path <- "/pet/{petId}"
+      url_path <- "/pet/{petId}?streaming"
      if (!missing(`pet_id`)) {
        url_path <- gsub(paste0("\\{", "petId", "\\}"), URLencode(as.character(`pet_id`), reserved = TRUE), url_path)
      }
--- a/samples/client/petstore/R/README.md
+++ b/samples/client/petstore/R/README.md
@@ -63,12 +63,13 @@ Class | Method | HTTP request | Description
 ------------ | ------------- | ------------- | -------------
 *FakeApi* | [**FakeDataFile**](docs/FakeApi.md#FakeDataFile) | **GET** /fake/data_file | test data_file to ensure it's escaped correctly
 *PetApi* | [**AddPet**](docs/PetApi.md#AddPet) | **POST** /pet | Add a new pet to the store
-*PetApi* | [**DeletePet**](docs/PetApi.md#DeletePet) | **DELETE** /pet/{petId} | Deletes a pet
+*PetApi* | [**DeletePet**](docs/PetApi.md#DeletePet) | **DELETE** /pet/{petId}?streaming | Deletes a pet
 *PetApi* | [**FindPetsByStatus**](docs/PetApi.md#FindPetsByStatus) | **GET** /pet/findByStatus | Finds Pets by status
 *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* | [**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* | [**UpdatePetWithForm**](docs/PetApi.md#UpdatePetWithForm) | **POST** /pet/{petId}?streaming | Updates a pet in the store with form data
 *PetApi* | [**UploadFile**](docs/PetApi.md#UploadFile) | **POST** /pet/{petId}/uploadImage | uploads an image
 *StoreApi* | [**DeleteOrder**](docs/StoreApi.md#DeleteOrder) | **DELETE** /store/order/{orderId} | Delete purchase order by ID
 *StoreApi* | [**GetInventory**](docs/StoreApi.md#GetInventory) | **GET** /store/inventory | Returns pet inventories by status
--- a/samples/client/petstore/R/docs/PetApi.md
+++ b/samples/client/petstore/R/docs/PetApi.md
@@ -5,12 +5,13 @@ All URIs are relative to *http://petstore.swagger.io/v2*
 Method | HTTP request | Description
 ------------- | ------------- | -------------
 [**AddPet**](PetApi.md#AddPet) | **POST** /pet | Add a new pet to the store
-[**DeletePet**](PetApi.md#DeletePet) | **DELETE** /pet/{petId} | Deletes a pet
+[**DeletePet**](PetApi.md#DeletePet) | **DELETE** /pet/{petId}?streaming | Deletes a pet
 [**FindPetsByStatus**](PetApi.md#FindPetsByStatus) | **GET** /pet/findByStatus | Finds Pets by status
 [**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)
 [**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
+[**UpdatePetWithForm**](PetApi.md#UpdatePetWithForm) | **POST** /pet/{petId}?streaming | Updates a pet in the store with form data
 [**UploadFile**](PetApi.md#UploadFile) | **POST** /pet/{petId}/uploadImage | uploads an image


@@ -317,6 +318,68 @@ Name | Type | Description  | Notes
 | **400** | Invalid ID supplied |  -  |
 | **404** | Pet not found |  -  |

+# **GetPetByIdStreaming**
+> Pet GetPetByIdStreaming(pet_id)
+
+Find pet by ID (streaming)
+
+Returns a single pet
+
+### Example
+```R
+library(petstore)
+
+var_pet_id <- 56 # integer | ID of pet to return
+
+#Find pet by ID (streaming)
+api_instance <- PetApi$new()
+# Configure API key authorization: api_key
+api_instance$api_client$api_keys['api_key'] <- 'TODO_YOUR_API_KEY';
+result <- tryCatch(
+             # to save the result into a file, simply add the optional `data_file` parameter, e.g.
+             # api_instance$GetPetByIdStreaming(var_pet_id, data_file = "result.txt"),
+             api_instance$GetPetByIdStreaming(var_pet_id, stream_callback = function(x){ print(length(x)) }),
+             ApiException = function(ex) ex
+          )
+# In case of error, print the error object
+if (!is.null(result$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
+}
+```
+
+### Parameters
+
+Name | Type | Description  | Notes
+------------- | ------------- | ------------- | -------------
+ **pet_id** | **integer**| ID of pet to return | 
+
+### 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)

--- a/samples/client/petstore/R/test_petstore.R
+++ b/samples/client/petstore/R/test_petstore.R
@@ -2,25 +2,35 @@
 install.packages("petstore_1.0.0.tar.gz",repos=NULL, type="source")
 library(petstore)

-#errorMsg <- "{\"code\":1,\"type\":\"error\",\"message\":\"Pet not found\"}"
-##errorMsg <- '{"code": 404, "message": "Not found"}'
-#a <- ModelApiResponse$new()$fromJSONString(errorMsg)
-#dput(a)
-#
-#var_pet_id <- 1231256 # integer | ID of pet to return
-#
-##Find pet by ID
-#api_instance <- PetApi$new()
-## Configure API key authorization: api_key
-#api_instance$api_client$api_keys['api_key'] <- 'TODO_YOUR_API_KEY';
-#result <- tryCatch(
-#             api_instance$GetPetById(var_pet_id),
-#             ApiException = function(ex) ex
-#          )
-## In case of error, print the error object
-#if(!is.null(result$ApiException)) {
+var_pet <- Pet$new("name_example", list("photoUrls_example"), 56, Category$new(56, "name_example"), list(Tag$new(56, "name_example")), "available") # Pet | Pet object that needs to be added to the store
+
+#Add a new pet to the store
+api_instance <- PetApi$new()
+# Configure OAuth2 access token for authorization: petstore_auth
+api_instance$api_client$access_token <- 'TODO_YOUR_ACCESS_TOKEN';
+result <- tryCatch(
+             # to save the result into a file, simply add the optional `data_file` parameter, e.g.
+             # api_instance$AddPet(var_pet, data_file = "result.txt"),
+             api_instance$AddPet(var_pet),
+             ApiException = function(ex) ex
+          )
+
+var_pet_id <- 56 # integer | ID of pet to return
+
+#Find pet by ID (streaming)
+api_instance <- PetApi$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$GetPetByIdStreaming(var_pet_id, data_file = "result.txt"),
+             api_instance$GetPetByIdStreaming(var_pet_id, stream_callback = function(x) { print(x) }),
+             ApiException = function(ex) ex
+          )
+# In case of error, print the error object
+#if (!is.null(result$ApiException)) {
 #  cat(result$ApiException$toString())
-#} else {
+#} #else {
 #  # deserialized response object
 #  response.object <- result$content
 #  # response headers
@@ -29,75 +39,103 @@ library(petstore)
 #  response.status.code <- result$response$status_code
 #}

-json2 <-
-'{"name": "pet", "photoUrls" : ["http://a.com", "http://b.com"]}'

-jsonlite::minify(json2)
-
-pet_api <- PetApi$new()
-pet_id <- 123321
-pet <- Pet$new("name_test",
-  photoUrls = list("photo_test", "second test"),
-  category = Category$new(id = 450, name = "test_cat"),
-  id = pet_id,
-  tags = list(
-    Tag$new(id = 123, name = "tag_test"), Tag$new(id = 456, name = "unknown")
-  ),
-  status = "available"
-)
-
-#jsonlite::minify(pet$toJSONString())
-#cat(pet$toJSONString())
-toString(pet$toString())
-
-#json <-
-#'[
-#  {"Name" : "Mario", "Age" : 32, "Occupation" : "Plumber"}, 
-#  {"Name" : "Peach", "Age" : 21, "Occupation" : "Princess"},
-#  {},
-#  {"Name" : "Bowser", "Occupation" : "Koopa"}
-#]'
+##errorMsg <- "{\"code\":1,\"type\":\"error\",\"message\":\"Pet not found\"}"
+###errorMsg <- '{"code": 404, "message": "Not found"}'
+##a <- ModelApiResponse$new()$fromJSONString(errorMsg)
+##dput(a)
+##
+##var_pet_id <- 1231256 # integer | ID of pet to return
+##
+###Find pet by ID
+##api_instance <- PetApi$new()
+### Configure API key authorization: api_key
+##api_instance$api_client$api_keys['api_key'] <- 'TODO_YOUR_API_KEY';
+##result <- tryCatch(
+##             api_instance$GetPetById(var_pet_id),
+##             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
+##}
 #
+#json2 <-
+#'{"name": "pet", "photoUrls" : ["http://a.com", "http://b.com"]}'
 #
-##Pet$public_methods
-##Pet$public_methods$fromJSON(json)
-##Pet$public_methods$toJson()
-##Pet$public_methods$validateJSON(json2)
-##Pet$public_methods$validateJson(json)
-##Pet$my_static_method <- function(x) { x + 2}
-##Pet$public_methods$my_static_method(1)
+#jsonlite::minify(json2)
 #
-  basque_pig_json <-
-  '{"className2": "BasquePig", "color": "red"}'
-# 
-#  danish_pig_json <-
-#  '{"className2": "DanishPig", "size": 7}'
-# 
-#  wrong_json <- 
-#  '[
-#    {"Name" : "Tom", "Age" : 32, "Occupation" : "Consultant"}, 
-#    {},
-#    {"Name" : "Ada", "Occupation" : "Engineer"}
-#  ]'
+#pet_api <- PetApi$new()
+#pet_id <- 123321
+#pet <- Pet$new("name_test",
+#  photoUrls = list("photo_test", "second test"),
+#  category = Category$new(id = 450, name = "test_cat"),
+#  id = pet_id,
+#  tags = list(
+#    Tag$new(id = 123, name = "tag_test"), Tag$new(id = 456, name = "unknown")
+#  ),
+#  status = "available"
+#)
 #
-#  print("==========") 
-  pig <- Pig$new()
-  basque_pig <- pig$fromJSON(basque_pig_json)
-#  #print(basque_pig$actual_instance$color)
-#  #expect_equal(basque_pig$actual_type, "BasquePig")
-#  pig$fromJSON(danish_pig_json)
-#  #pig$fromJSON(wrong_json)
-#  pig$toJSON()
+##jsonlite::minify(pet$toJSONString())
+##cat(pet$toJSONString())
+#toString(pet$toString())
 #
-#  #d <- DanishPig$new()
-#  #dp <- d$validateJSON(danish_pig_json)
+##json <-
+##'[
+##  {"Name" : "Mario", "Age" : 32, "Occupation" : "Plumber"}, 
+##  {"Name" : "Peach", "Age" : 21, "Occupation" : "Princess"},
+##  {},
+##  {"Name" : "Bowser", "Occupation" : "Koopa"}
+##]'
+##
+##
+###Pet$public_methods
+###Pet$public_methods$fromJSON(json)
+###Pet$public_methods$toJson()
+###Pet$public_methods$validateJSON(json2)
+###Pet$public_methods$validateJson(json)
+###Pet$my_static_method <- function(x) { x + 2}
+###Pet$public_methods$my_static_method(1)
+##
+#  basque_pig_json <-
+#  '{"className2": "BasquePig", "color": "red"}'
+## 
+##  danish_pig_json <-
+##  '{"className2": "DanishPig", "size": 7}'
+## 
+##  wrong_json <- 
+##  '[
+##    {"Name" : "Tom", "Age" : 32, "Occupation" : "Consultant"}, 
+##    {},
+##    {"Name" : "Ada", "Occupation" : "Engineer"}
+##  ]'
+##
+##  print("==========") 
+#  pig <- Pig$new()
+#  basque_pig <- pig$fromJSON(basque_pig_json)
+##  #print(basque_pig$actual_instance$color)
+##  #expect_equal(basque_pig$actual_type, "BasquePig")
+##  pig$fromJSON(danish_pig_json)
+##  #pig$fromJSON(wrong_json)
+##  pig$toJSON()
+##
+##  #d <- DanishPig$new()
+##  #dp <- d$validateJSON(danish_pig_json)
+##
+##
 #
+## test nested oneOf
+#nested_oneof <- NestedOneOf$new()
+#nested_oneof$nested_pig <- pig
+#nested_oneof$size <- 15
+#
+#cat(nested_oneof$toJSONString())
 #
-
-# test nested oneOf
-nested_oneof <- NestedOneOf$new()
-nested_oneof$nested_pig <- pig
-nested_oneof$size <- 15
-
-cat(nested_oneof$toJSONString())
-
--- a/samples/client/petstore/R/tests/testthat/test_petstore.R
+++ b/samples/client/petstore/R/tests/testthat/test_petstore.R
@@ -92,6 +92,13 @@ test_that("GetPetById", {
  )
 })

+test_that("GetPetByIdStreaming", {
+  result <- tryCatch(
+               pet_api$GetPetByIdStreaming(pet_id, stream_callback = function(x) { print(x) }),
+               ApiException = function(ex) ex
+            )
+})
+
 #test_that("test GetPetById exception", {
 #  # test exception 
 #  result <- tryCatch(petApi$GetPetById(98765), # petId not exist