fix: send request body for OpenAPI 3.x operations that declare parameters

src/codegen/inputs/openapi/generators/payloads.ts

@@ -152,22 +152,26 @@ function extractPayloadsFromOperations(
         path: pathKey
       });
 
-      // Extract request payload schema
+      // Extract request payload schema.
+      // Prefer the 3.x `requestBody`: 3.x operations also carry a `parameters`
+      // array (path/query/header), so presence of `parameters` cannot be used
+      // to detect 2.0 - doing so would drop the body on any 3.x operation that
+      // declares parameters. The 2.0 body lives in a `parameters` entry with
+      // `in: 'body'`, so fall back to that only when there is no `requestBody`.
       let requestSchema: any = null;
 
-      // Check if this is OpenAPI 2.0 vs 3.x based on the structure
-      if ('parameters' in operationObj && operationObj.parameters) {
-        // OpenAPI 2.0 style
-        requestSchema = extractOpenAPI2RequestSchema(
-          operationObj.parameters as OpenAPIV2.ParameterObject[]
-        );
-      } else if ('requestBody' in operationObj && operationObj.requestBody) {
+      if ('requestBody' in operationObj && operationObj.requestBody) {
         // OpenAPI 3.x style
         requestSchema = extractOpenAPI3RequestSchema(
           operationObj.requestBody as
             | OpenAPIV3.RequestBodyObject
             | OpenAPIV3_1.RequestBodyObject
         );
+      } else if ('parameters' in operationObj && operationObj.parameters) {
+        // OpenAPI 2.0 style (body carried as a `in: 'body'` parameter)
+        requestSchema = extractOpenAPI2RequestSchema(
+          operationObj.parameters as OpenAPIV2.ParameterObject[]
+        );
       }
 
       if (requestSchema) {

test/codegen/generators/typescript/payload.spec.ts

@@ -193,6 +193,10 @@ describe('payloads', () => {
           key: "createUsersWithListInput",
           value: "CreateUsersWithListInputRequest",
         },
+        {
+          key: "updateUser",
+          value: "AUser",
+        },
         {
           key: "addPet_Response",
           value: "APet",
@@ -277,6 +281,10 @@ describe('payloads', () => {
           key: "createUsersWithListInput",
           value: "CreateUsersWithListInputRequest",
         },
+        {
+          key: "updateUser",
+          value: "AUser",
+        },
         {
           key: "addPet_Response",
           value: "APet",

test/codegen/inputs/openapi/payloads.spec.ts

@@ -0,0 +1,60 @@
+import {OpenAPIV3} from 'openapi-types';
+import {processOpenAPIPayloads} from '../../../../src/codegen/inputs/openapi/generators/payloads';
+
+describe('OpenAPI payload extraction', () => {
+  describe('processOpenAPIPayloads', () => {
+    it('extracts the request body of a 3.x operation that also declares parameters', () => {
+      // Regression: a 3.x operation carrying both `parameters` (header/path/query)
+      // and a `requestBody` must not be mistaken for OpenAPI 2.0 - the body was
+      // previously dropped whenever any parameter was present.
+      const document: OpenAPIV3.Document = {
+        openapi: '3.0.0',
+        info: {title: 'Test API', version: '1.0.0'},
+        paths: {
+          '/things': {
+            post: {
+              parameters: [
+                {
+                  name: 'X-Correlation-Id',
+                  in: 'header',
+                  schema: {type: 'string'}
+                }
+              ],
+              requestBody: {
+                required: true,
+                content: {
+                  'application/json': {
+                    schema: {
+                      type: 'object',
+                      properties: {name: {type: 'string'}}
+                    }
+                  }
+                }
+              },
+              responses: {
+                200: {
+                  description: 'OK',
+                  content: {
+                    'application/json': {
+                      schema: {type: 'object', properties: {id: {type: 'string'}}}
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      };
+
+      const {operationPayloads} = processOpenAPIPayloads(document);
+
+      // The request body surfaces as an operation payload whose schema id ends
+      // in `Request`; before the fix only the `Response` payload was present.
+      const schemaIds = Object.values(operationPayloads).map(
+        (payload) => payload.schemaId
+      );
+      expect(schemaIds.some((id) => id.endsWith('Request'))).toBe(true);
+      expect(schemaIds.some((id) => id.endsWith('Response'))).toBe(true);
+    });
+  });
+});