fix(build-request): create proper accept header (#1981)

Set accept header according to the the produces content-types defined in the API.
This fix uses the content-type defined in the operation and sets the accept header, 
to contain all of these content-types. If the option responseContentType is provided,
only this value will be set as accept header.

Closes #1116

Author: Andy2003

src/execute/oas3/build-request.js

@@ -2,6 +2,7 @@
 // `src/execute/index.js#buildRequest`
 import assign from 'lodash/assign';
 import get from 'lodash/get';
+import isPlainObject from 'lodash/isPlainObject';
 import btoa from 'btoa';
 
 export default function buildRequest(options, req) {
@@ -37,6 +38,17 @@ export default function buildRequest(options, req) {
   } else if (requestContentType && isExplicitContentTypeValid) {
     req.headers['Content-Type'] = requestContentType;
   }
+  if (!options.responseContentType && operation.responses) {
+    const mediaTypes = Object.entries(operation.responses)
+      .filter(([key, value]) => {
+        const code = parseInt(key, 10);
+        return code >= 200 && code < 300 && isPlainObject(value.content);
+      })
+      .reduce((acc, [, value]) => acc.concat(Object.keys(value.content)), []);
+    if (mediaTypes.length > 0) {
+      req.headers.accept = mediaTypes.join(', ');
+    }
+  }
 
   // for OAS3: add requestBody to request
   if (requestBody) {

src/execute/swagger2/build-request.js

@@ -9,6 +9,7 @@ export default function buildRequest(options, req) {
     operation,
     securities,
     requestContentType,
+    responseContentType,
     attachContentTypeForEmptyPayload,
   } = options;
   // Add securities, which are applicable
@@ -47,6 +48,9 @@ export default function buildRequest(options, req) {
       req.headers['Content-Type'] = requestContentType;
     }
   }
+  if (!responseContentType && Array.isArray(operation.produces) && operation.produces.length > 0) {
+    req.headers.accept = operation.produces.join(', ');
+  }
 
   return req;
 }

test/execute/main.js

@@ -880,6 +880,7 @@ describe('execute', () => {
         method: 'PUT',
         credentials: 'same-origin',
         headers: {
+          accept: 'mime/silent-french-type',
           head: 'justTheHead',
         },
         body: {

test/oas3/execute/build-request.js

@@ -0,0 +1,84 @@
+// https://github.com/swagger-api/swagger-js/issues/1116
+import { buildRequest } from '../../../src/execute';
+
+describe('buildRequest - OAS 3.0.x', () => {
+  describe('test accept header', () => {
+    const spec = {
+      openapi: '3.0.0',
+      servers: [
+        {
+          url: 'https://test.com/v1',
+        },
+      ],
+      paths: {
+        '/getMultiple': {
+          get: {
+            operationId: 'getMultiple',
+            responses: {
+              200: {
+                content: {
+                  'application/xml': {
+                    schema: {
+                      type: 'array',
+                      items: 'string',
+                    },
+                  },
+                  'application/json': {
+                    schema: {
+                      type: 'array',
+                      items: 'string',
+                    },
+                  },
+                },
+              },
+              default: {
+                description: 'Unexpected error',
+                content: {
+                  'application/json': {
+                    schema: {
+                      type: 'array',
+                      items: 'string',
+                    },
+                  },
+                },
+              },
+            },
+          },
+        },
+      },
+    };
+
+    test('should generate accept header according to defined responses', () => {
+      const req = buildRequest({
+        spec,
+        operationId: 'getMultiple',
+      });
+
+      expect(req).toEqual({
+        url: 'https://test.com/v1/getMultiple',
+        method: 'GET',
+        credentials: 'same-origin',
+        headers: {
+          accept: 'application/xml, application/json',
+        },
+      });
+    });
+
+    test('should allow to override accept header according to defined responses', () => {
+      const req = buildRequest({
+        spec,
+        operationId: 'getMultiple',
+        responseContentType: 'application/xml',
+      });
+
+      expect(req).toEqual({
+        url: 'https://test.com/v1/getMultiple',
+        method: 'GET',
+        credentials: 'same-origin',
+        headers: {
+          accept: 'application/xml',
+        },
+      });
+    });
+  });
+});

test/swagger2/execute/build-request.js

@@ -284,4 +284,61 @@ describe('buildRequest - swagger 2.0', () => {
       });
     });
   });
+
+  describe('test accept header', () => {
+    const spec = {
+      host: 'test.com',
+      basePath: '/v1',
+      schemes: ['https'],
+      paths: {
+        '/getMultiple': {
+          get: {
+            operationId: 'getMultiple',
+            produces: ['application/xml', 'application/json'],
+            responses: {
+              200: {
+                schema: {
+                  type: 'array',
+                  items: 'string',
+                },
+              },
+            },
+          },
+        },
+      },
+    };
+
+    test('should generate accept header according to defined responses', () => {
+      const req = buildRequest({
+        spec,
+        operationId: 'getMultiple',
+      });
+
+      expect(req).toEqual({
+        url: 'https://test.com/v1/getMultiple',
+        method: 'GET',
+        credentials: 'same-origin',
+        headers: {
+          accept: 'application/xml, application/json',
+        },
+      });
+    });
+
+    test('should allow to override accept header according to defined responses', () => {
+      const req = buildRequest({
+        spec,
+        operationId: 'getMultiple',
+        responseContentType: 'application/xml',
+      });
+
+      expect(req).toEqual({
+        url: 'https://test.com/v1/getMultiple',
+        method: 'GET',
+        credentials: 'same-origin',
+        headers: {
+          accept: 'application/xml',
+        },
+      });
+    });
+  });
 });