fix(error-handling-middleware): handle str error as ApiError

Author: naorpeled

README.md

@@ -1310,7 +1310,7 @@ api.use(errorHandler1,errorHandler2)
 
 ### Error Types
 
-Lambda API provides several different types of errors that can be used by your application. `RouteError`, `MethodError`, `ResponseError`, and `FileError` will all be passed to your error middleware. `ConfigurationError`s will throw an exception when you attempt to `.run()` your route and can be caught in a `try/catch` block. Most error types contain additional properties that further detail the issue.
+Lambda API provides several different types of errors that can be used by your application. `ApiError`, `RouteError`, `MethodError`, `ResponseError`, and `FileError` will all be passed to your error middleware. `ConfigurationError`s will throw an exception when you attempt to `.run()` your route and can be caught in a `try/catch` block. Most error types contain additional properties that further detail the issue.
 
 ```javascript
 const errorHandler = (err,req,res,next) => {

__tests__/errorHandling.unit.js

@@ -369,6 +369,13 @@ export declare class ResponseError extends Error {
   constructor(message: string, code: number);
 }
 
+export declare class ApiError extends Error {
+  constructor(message: string, code?: number, detail?: any);
+  name: 'ApiError';
+  code?: number;
+  detail?: any;
+}
+
 export declare class FileError extends Error {
   constructor(message: string, err: object);
 }

index.d.ts

@@ -10,8 +10,8 @@ const RESPONSE = require('./lib/response');
 const UTILS = require('./lib/utils');
 const LOGGER = require('./lib/logger');
 const S3 = () => require('./lib/s3-service');
+const { ConfigurationError, ApiError } = require('./lib/errors');
 const prettyPrint = require('./lib/prettyPrint');
-const { ConfigurationError } = require('./lib/errors');
 
 class API {
   constructor(props) {
@@ -328,26 +328,21 @@ class API {
 
   // Catch all async/sync errors
   async catchErrors(e, response, code, detail) {
-    // Error messages should respect the app's base64 configuration
     response._isBase64 = this._isBase64;
 
-    // Strip the headers, keep whitelist
     const strippedHeaders = Object.entries(response._headers).reduce(
       (acc, [headerName, value]) => {
         if (!this._errorHeaderWhitelist.includes(headerName.toLowerCase())) {
           return acc;
         }
-
         return Object.assign(acc, { [headerName]: value });
       },
       {}
     );
 
     response._headers = Object.assign(strippedHeaders, this._headers);
-
     let message;
 
-    // Set the status code
     response.status(code ? code : this._errorStatus);
 
     let info = {
@@ -357,13 +352,15 @@ class API {
       stack: (this._logger.stack && e.stack) || undefined,
     };
 
-    if (e instanceof Error) {
+    const isApiError = e instanceof ApiError;
+
+    if (e instanceof Error && !isApiError) {
       message = e.message;
       if (this._logger.errorLogging) {
         this.log.fatal(message, info);
       }
     } else {
-      message = e;
+      message = e instanceof Error ? e.message : e;
       if (this._logger.errorLogging) {
         this.log.error(message, info);
       }
@@ -387,7 +384,7 @@ class API {
           if (rtn) response.send(rtn);
           r();
         });
-      } // end for
+      }
     }
 
     // Throw standard error unless callback has already been executed

index.js

@@ -17,6 +17,7 @@ import {
   ConfigurationError,
   ResponseError,
   FileError,
+  ApiError,
 } from './index';
 import {
   APIGatewayProxyEvent,
@@ -255,3 +256,12 @@ const fileError = new FileError('File not found', {
   syscall: 'open',
 });
 expectType<FileError>(fileError);
+expectType<string>(fileError.message);
+expectType<string>(fileError.name);
+expectType<string | undefined>(fileError.stack);
+
+const apiError = new ApiError('Api error', 500);
+expectType<ApiError>(apiError);
+expectType<string>(apiError.message);
+expectType<number | undefined>(apiError.code);
+expectType<any>(apiError.detail);

index.test-d.ts

@@ -41,6 +41,17 @@ class ResponseError extends Error {
   }
 }
 
+class ApiError extends Error {
+  constructor(message, code, detail) {
+    super(message);
+    this.name = 'ApiError';
+    this.code = typeof code === 'number' ? code : 500;
+    if (detail !== undefined) {
+      this.detail = detail;
+    }
+  }
+}
+
 class FileError extends Error {
   constructor(message, err) {
     super(message);
@@ -55,5 +66,6 @@ module.exports = {
   MethodError,
   ConfigurationError,
   ResponseError,
+  ApiError,
   FileError,
 };

lib/errors.js

@@ -10,7 +10,7 @@ const UTILS = require('./utils.js');
 const fs = require('fs'); // Require Node.js file system
 const path = require('path'); // Require Node.js path
 const compression = require('./compression'); // Require compression lib
-const { ResponseError, FileError } = require('./errors'); // Require custom errors
+const { ResponseError, FileError, ApiError } = require('./errors'); // Require custom errors
 
 // Lazy load AWS S3 service
 const S3 = () => require('./s3-service');
@@ -248,7 +248,7 @@ class RESPONSE {
     // secure (Boolean): Marks the cookie to be used with HTTPS only
     cookieString += opts.secure && opts.secure === true ? '; Secure' : '';
 
-    // sameSite (Boolean or String) Value of the “SameSite” Set-Cookie attribute
+    // sameSite (Boolean or String) Value of the "SameSite" Set-Cookie attribute
     // see https://tools.ietf.org/html/draft-ietf-httpbis-cookie-same-site-00#section-4.1.1.
     cookieString +=
       opts.sameSite !== undefined
@@ -594,10 +594,17 @@ class RESPONSE {
 
   // Trigger API error
   error(code, e, detail) {
-    detail = typeof code !== 'number' && e !== undefined ? e : detail;
-    e = typeof code !== 'number' ? code : e;
-    code = typeof code === 'number' ? code : undefined;
-    this.app.catchErrors(e, this, code, detail);
+    const message = typeof code !== 'number' ? code : e;
+    const statusCode = typeof code === 'number' ? code : undefined;
+    const errorDetail =
+      typeof code !== 'number' && e !== undefined ? e : detail;
+
+    const errorToSend =
+      typeof message === 'string'
+        ? new ApiError(message, statusCode, errorDetail)
+        : message;
+
+    this.app.catchErrors(errorToSend, this, statusCode, errorDetail);
   } // end error
 } // end Response class