Fix 'Maximum call stack size exceeded' issue with OpenAPI & swagger c…

…ircular references

src/processors/JsonSchemaInputProcessor.ts

@@ -105,6 +105,7 @@ export class JsonSchemaInputProcessor extends AbstractInputProcessor {
     input = JsonSchemaInputProcessor.reflectSchemaNames(
       input,
       {},
+      new Set(),
       'root',
       true
     );
@@ -134,6 +135,7 @@ export class JsonSchemaInputProcessor extends AbstractInputProcessor {
     input = JsonSchemaInputProcessor.reflectSchemaNames(
       input,
       {},
+      new Set(),
       'root',
       true
     );
@@ -163,6 +165,7 @@ export class JsonSchemaInputProcessor extends AbstractInputProcessor {
     input = JsonSchemaInputProcessor.reflectSchemaNames(
       input,
       {},
+      new Set(),
       'root',
       true
     );
@@ -258,7 +261,8 @@ export class JsonSchemaInputProcessor extends AbstractInputProcessor {
    * This reflects all the common keywords that are shared between draft-4, draft-7 and Swagger 2.0 Schema
    *
    * @param schema to process
-   * @param namesStack is a aggegator of previous used names
+   * @param namesStack is a aggregator of previous used names
+   * @param seenSchemas is a set of schema already seen and named
    * @param name to infer
    * @param isRoot indicates if performed schema is a root schema
    */
@@ -272,14 +276,28 @@ export class JsonSchemaInputProcessor extends AbstractInputProcessor {
       | OpenapiV3Schema
       | boolean,
     namesStack: Record<string, number>,
+    seenSchemas: Set<
+      | Draft4Schema
+      | Draft6Schema
+      | Draft7Schema
+      | SwaggerV2Schema
+      | OpenapiV3Schema
+    >,
     name?: string,
     isRoot?: boolean
   ): any {
     if (typeof schema === 'boolean') {
       return schema;
     }
 
+    // short-circuit circular references
+    if (seenSchemas.has(schema)) {
+      return schema;
+    }
+    seenSchemas.add(schema);
+
     schema = { ...schema };
+
     if (isRoot) {
       namesStack[String(name)] = 0;
       (schema as any)[this.MODELGEN_INFFERED_NAME] = name;
@@ -304,6 +322,7 @@ export class JsonSchemaInputProcessor extends AbstractInputProcessor {
         this.reflectSchemaNames(
           item,
           namesStack,
+          seenSchemas,
           this.ensureNamePattern(name, 'allOf', idx)
         )
       );
@@ -313,6 +332,7 @@ export class JsonSchemaInputProcessor extends AbstractInputProcessor {
         this.reflectSchemaNames(
           item,
           namesStack,
+          seenSchemas,
           this.ensureNamePattern(name, 'oneOf', idx)
         )
       );
@@ -322,6 +342,7 @@ export class JsonSchemaInputProcessor extends AbstractInputProcessor {
         this.reflectSchemaNames(
           item,
           namesStack,
+          seenSchemas,
           this.ensureNamePattern(name, 'anyOf', idx)
         )
       );
@@ -330,6 +351,7 @@ export class JsonSchemaInputProcessor extends AbstractInputProcessor {
       schema.not = this.reflectSchemaNames(
         schema.not,
         namesStack,
+        seenSchemas,
         this.ensureNamePattern(name, 'not')
       );
     }
@@ -340,6 +362,7 @@ export class JsonSchemaInputProcessor extends AbstractInputProcessor {
       schema.additionalItems = this.reflectSchemaNames(
         schema.additionalItems,
         namesStack,
+        seenSchemas,
         this.ensureNamePattern(name, 'additionalItem')
       );
     }
@@ -350,6 +373,7 @@ export class JsonSchemaInputProcessor extends AbstractInputProcessor {
       schema.additionalProperties = this.reflectSchemaNames(
         schema.additionalProperties,
         namesStack,
+        seenSchemas,
         this.ensureNamePattern(name, 'additionalProperty')
       );
     }
@@ -360,13 +384,15 @@ export class JsonSchemaInputProcessor extends AbstractInputProcessor {
             this.reflectSchemaNames(
               item,
               namesStack,
+              seenSchemas,
               this.ensureNamePattern(name, 'item', idx)
             )
         );
       } else {
         schema.items = this.reflectSchemaNames(
           schema.items,
           namesStack,
+          seenSchemas,
           this.ensureNamePattern(name, 'item')
         );
       }
@@ -380,6 +406,7 @@ export class JsonSchemaInputProcessor extends AbstractInputProcessor {
         properties[String(propertyName)] = this.reflectSchemaNames(
           propertySchema,
           namesStack,
+          seenSchemas,
           this.ensureNamePattern(name, propertyName)
         );
       }
@@ -394,6 +421,7 @@ export class JsonSchemaInputProcessor extends AbstractInputProcessor {
           dependencies[String(dependencyName)] = this.reflectSchemaNames(
             dependency as any,
             namesStack,
+            seenSchemas,
             this.ensureNamePattern(name, dependencyName)
           );
         } else {
@@ -412,6 +440,7 @@ export class JsonSchemaInputProcessor extends AbstractInputProcessor {
           this.reflectSchemaNames(
             patternProperty as any,
             namesStack,
+            seenSchemas,
             this.ensureNamePattern(name, 'pattern_property', idx)
           );
       }
@@ -425,6 +454,7 @@ export class JsonSchemaInputProcessor extends AbstractInputProcessor {
         definitions[String(definitionName)] = this.reflectSchemaNames(
           definition,
           namesStack,
+          seenSchemas,
           this.ensureNamePattern(name, definitionName)
         );
       }
@@ -437,13 +467,15 @@ export class JsonSchemaInputProcessor extends AbstractInputProcessor {
         schema.contains = this.reflectSchemaNames(
           schema.contains,
           namesStack,
+          seenSchemas,
           this.ensureNamePattern(name, 'contain')
         );
       }
       if (schema.propertyNames !== undefined) {
         schema.propertyNames = this.reflectSchemaNames(
           schema.propertyNames,
           namesStack,
+          seenSchemas,
           this.ensureNamePattern(name, 'propertyName')
         );
       }
@@ -453,20 +485,23 @@ export class JsonSchemaInputProcessor extends AbstractInputProcessor {
           schema.if = this.reflectSchemaNames(
             schema.if,
             namesStack,
+            seenSchemas,
             this.ensureNamePattern(name, 'if')
           );
         }
         if (schema.then !== undefined) {
           schema.then = this.reflectSchemaNames(
             schema.then,
             namesStack,
+            seenSchemas,
             this.ensureNamePattern(name, 'then')
           );
         }
         if (schema.else !== undefined) {
           schema.else = this.reflectSchemaNames(
             schema.else,
             namesStack,
+            seenSchemas,
             this.ensureNamePattern(name, 'else')
           );
         }

src/processors/OpenAPIInputProcessor.ts

@@ -271,6 +271,7 @@ export class OpenAPIInputProcessor extends AbstractInputProcessor {
     const namedSchema = JsonSchemaInputProcessor.reflectSchemaNames(
       schema,
       {},
+      new Set(),
       name,
       true
     );

src/processors/SwaggerInputProcessor.ts

@@ -172,6 +172,7 @@ export class SwaggerInputProcessor extends AbstractInputProcessor {
     schema = JsonSchemaInputProcessor.reflectSchemaNames(
       schema,
       {},
+      new Set(),
       name,
       true
     );

test/processors/JsonSchemaInputProcessor.spec.ts

@@ -385,6 +385,7 @@ describe('JsonSchemaInputProcessor', () => {
       const expected = JsonSchemaInputProcessor.reflectSchemaNames(
         schema,
         {},
+        new Set(),
         'root',
         true
       ) as any;

test/processors/OpenAPIInputProcessor.spec.ts

@@ -8,6 +8,12 @@ const basicDoc = JSON.parse(
     'utf8'
   )
 );
+const circularDoc = JSON.parse(
+  fs.readFileSync(
+    path.resolve(__dirname, './OpenAPIInputProcessor/references_circular.json'),
+    'utf8'
+  )
+);
 jest.mock('../../src/utils/LoggingInterface');
 const processorSpy = jest.spyOn(
   OpenAPIInputProcessor,
@@ -134,5 +140,11 @@ describe('OpenAPIInputProcessor', () => {
         'test_parameters_header_path_parameter'
       ]);
     });
+    test('should be able to use $ref when circular', async () => {
+      const processor = new OpenAPIInputProcessor();
+      const commonInputModel = await processor.process(circularDoc);
+      expect(commonInputModel).toMatchSnapshot();
+      expect(processorSpy.mock.calls).toMatchSnapshot();
+    });
   });
 });

test/processors/OpenAPIInputProcessor/references_circular.json

@@ -0,0 +1,54 @@
+{
+  "openapi": "3.0.3",
+  "info": {
+    "title": "circular api"
+  },
+  "paths": {
+    "/test": {
+      "get": {
+        "requestBody": {
+          "content": {
+            "application/json": {
+              "schema": {
+                "$ref": "#/components/ApiResponse"
+              }
+            }
+          },
+          "required": true
+        },
+        "responses": {
+          "200": {
+            "description": "Successful operation",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/ApiResponse"
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  },
+  "components": {
+    "ApiResponse": {
+      "type": "object",
+      "properties": {
+        "code": {
+          "type": "integer",
+          "format": "int32"
+        },
+        "type": {
+          "type": "string"
+        },
+        "message": {
+          "type": "string"
+        },
+        "loop": {
+          "$ref": "#/components/ApiResponse"
+        }
+      }
+    }
+  }
+}

test/processors/SwaggerInputProcessor.spec.ts

@@ -9,6 +9,12 @@ const basicDoc = JSON.parse(
     'utf8'
   )
 );
+const circularDoc = JSON.parse(
+  fs.readFileSync(
+    path.resolve(__dirname, './SwaggerInputProcessor/references_circular.json'),
+    'utf8'
+  )
+);
 jest.mock('../../src/utils/LoggingInterface');
 jest.spyOn(SwaggerInputProcessor, 'convertToInternalSchema');
 const mockedReturnModels = [new CommonModel()];
@@ -27,6 +33,9 @@ jest.mock('../../src/interpreter/Interpreter', () => {
 });
 
 describe('SwaggerInputProcessor', () => {
+  beforeEach(() => {
+    jest.resetAllMocks();
+  });
   afterAll(() => {
     jest.restoreAllMocks();
   });
@@ -77,5 +86,20 @@ describe('SwaggerInputProcessor', () => {
         ).mock.calls
       ).toMatchSnapshot();
     });
+    test('should be able to use $ref when circular', async () => {
+      JsonSchemaInputProcessor.convertSchemaToMetaModel = jest
+        .fn()
+        .mockImplementation(() => {
+          return mockedMetaModel;
+        });
+      const processor = new SwaggerInputProcessor();
+      const commonInputModel = await processor.process(circularDoc);
+      expect(commonInputModel).toMatchSnapshot();
+      expect(
+        (
+          SwaggerInputProcessor.convertToInternalSchema as any as jest.SpyInstance
+        ).mock.calls
+      ).toMatchSnapshot();
+    });
   });
 });

test/processors/SwaggerInputProcessor/references_circular.json

@@ -0,0 +1,40 @@
+{
+  "swagger": "2.0",
+  "info": {
+    "title": "circular api"
+  },
+  "paths": {
+    "/test": {
+      "get": {
+        "responses": {
+          "200": {
+            "description": "successful operation",
+            "schema": {
+              "$ref": "#/definitions/ApiResponse"
+            }
+          }
+        }
+      }
+    }
+  },
+  "definitions": {
+    "ApiResponse": {
+      "type": "object",
+      "properties": {
+        "code": {
+          "type": "integer",
+          "format": "int32"
+        },
+        "type": {
+          "type": "string"
+        },
+        "message": {
+          "type": "string"
+        },
+        "loop": {
+          "$ref": "#/definitions/ApiResponse"
+        }
+      }
+    }
+  }
+}