feat(integrations): Call toJSON of originalException to extract more data (#4038)

* feat(integrations): Call toJSON of originalException to extract more data

Author: kamilogorek

packages/integrations/src/extraerrordata.ts

@@ -74,20 +74,43 @@ export class ExtraErrorData implements Integration {
   /**
    * Extract extra information from the Error object
    */
-  private _extractErrorData(error: ExtendedError): { [key: string]: unknown } | null {
+  private _extractErrorData(error: ExtendedError): Record<string, unknown> | null {
     // We are trying to enhance already existing event, so no harm done if it won't succeed
     try {
-      const nativeKeys = ['name', 'message', 'stack', 'line', 'column', 'fileName', 'lineNumber', 'columnNumber'];
-      const errorKeys = Object.getOwnPropertyNames(error).filter(key => nativeKeys.indexOf(key) === -1);
+      const nativeKeys = [
+        'name',
+        'message',
+        'stack',
+        'line',
+        'column',
+        'fileName',
+        'lineNumber',
+        'columnNumber',
+        'toJSON',
+      ];
 
-      if (errorKeys.length) {
-        const extraErrorInfo: { [key: string]: unknown } = {};
-        for (const key of errorKeys) {
-          const value = error[key];
+      const extraErrorInfo: Record<string, unknown> = {};
+
+      // We want only enumerable properties, thus `getOwnPropertyNames` is redundant here, as we filter keys anyway.
+      for (const key of Object.keys(error)) {
+        if (nativeKeys.indexOf(key) !== -1) {
+          continue;
+        }
+        const value = error[key];
+        extraErrorInfo[key] = isError(value) ? (value as Error).toString() : value;
+      }
+
+      // Check if someone attached `toJSON` method to grab even more properties (eg. axios is doing that)
+      if (typeof error.toJSON === 'function') {
+        const serializedError = error.toJSON() as Record<string, unknown>;
+
+        for (const key of Object.keys(serializedError)) {
+          const value = serializedError[key];
           extraErrorInfo[key] = isError(value) ? (value as Error).toString() : value;
         }
-        return extraErrorInfo;
       }
+
+      return extraErrorInfo;
     } catch (oO) {
       logger.error('Unable to extract extra data from the Error object:', oO);
     }

packages/integrations/test/extraerrordata.test.ts

@@ -88,4 +88,70 @@ describe('ExtraErrorData()', () => {
 
     expect(enhancedEvent).toEqual(event);
   });
+
+  it('should call toJSON of original exception and add its properties', () => {
+    const error = new TypeError('foo') as ExtendedError;
+    error.baz = 42;
+    error.foo = 'bar';
+    error.toJSON = function() {
+      return {
+        bar: 1337,
+        qux: `${this.message} but nicer`,
+      };
+    };
+
+    const enhancedEvent = extraErrorData.enhanceEventWithErrorData(event, {
+      originalException: error,
+    });
+
+    expect(enhancedEvent.contexts).toEqual({
+      TypeError: {
+        bar: 1337,
+        baz: 42,
+        foo: 'bar',
+        qux: 'foo but nicer',
+      },
+    });
+  });
+
+  it('toJSON props should have priority over directly assigned ones', () => {
+    const error = new TypeError('foo') as ExtendedError;
+    error.baz = 42;
+    error.toJSON = function() {
+      return {
+        baz: 1337,
+      };
+    };
+
+    const enhancedEvent = extraErrorData.enhanceEventWithErrorData(event, {
+      originalException: error,
+    });
+
+    expect(enhancedEvent.contexts).toEqual({
+      TypeError: {
+        baz: 1337,
+      },
+    });
+  });
+
+  it('toJSON props should allow for usage of native names', () => {
+    const error = new TypeError('foo') as ExtendedError;
+    error.baz = 42;
+    error.toJSON = function() {
+      return {
+        message: 'bar',
+      };
+    };
+
+    const enhancedEvent = extraErrorData.enhanceEventWithErrorData(event, {
+      originalException: error,
+    });
+
+    expect(enhancedEvent.contexts).toEqual({
+      TypeError: {
+        baz: 42,
+        message: 'bar',
+      },
+    });
+  });
 });