Issue #36 Upgrade to Middy v1.0

- Updated dependencies, imports, and unit tests
- Updated documentation
- Bumped to v3.0.0 for breaking change.

Author: Adam Fanello

docs/source/lambda_utils.rst

@@ -34,17 +34,11 @@ Used with API Gateway, the included middlewares:
      instance will not be destroyed and suffer a cold start on the next invocation.
 - Leverages async syntax.
 
-See `Middy middlewares <https://middy.js.org/docs/middlewares.html>`_ for details on those.
+See `Middy middlewares <https://middy.js.org/#available-middlewares>`_ for details on those.
 Not all Middy middlewares are in this implementation, only common ones that are generally useful in all
 APIs. You may extend LambdaUtils's ``wrapApiHandler()`` function in your projects,
 or use it as an example to write your own, to add more middleware!
 
-**WARNING**: Middy has, historically, introduced some `breaking changes <https://github.com/onicagroup/sailplane/issues/16>`_
-in previous minor version bumps. LambdaUtils has been built and tested with Middy
-0.29.0, and should continue to work with future versions, but bumping your
-Middy version beyond 0.29.0 may produce some weird errors.
-
-
 ``LambdaUtils`` depends on two other utilities to work:
 
 - :doc:`logger`
@@ -53,9 +47,26 @@ Middy version beyond 0.29.0 may produce some weird errors.
 Install
 ^^^^^^^
 
+**To use LambdaUtils v3.x with Middy v1.x.x (latest):**
+
+.. code-block:: shell
+
+    npm install @sailplane/lambda-utils@3 @sailplane/logger @middy/core @middy/http-cors @middy/http-event-normalizer @middy/http-header-normalizer @middy/http-json-body-parser
+
+The extra @middy/ middleware packages are optional if you write your own wrapper function that does not use them. See below.
+
+**To use LambdaUtils v2.x with Middy v0.x.x:**
+
 .. code-block:: shell
 
-    npm install @sailplane/lambda-utils @sailplane/logger middy
+    npm install @sailplane/lambda-utils@2 @sailplane/logger middy
+
+Upgrading
+^^^^^^^^^
+
+To upgrade from lambda-utils v1.x or v2.x to the latest, remove the old with ``npm rm middy``
+and then follow the install instructions above to install the latest. See also the
+`Middy upgrade instructions <https://middy.js.org/UPGRADE.html>`_.
 
 Examples
 ^^^^^^^^

lambda-utils/lib/lambda-utils.test.ts

@@ -12,9 +12,7 @@ describe("LambdaUtils", () => {
 
         test("wrapApiHandler apiSuccess", (endTest) => {
             // GIVEN
-            const expectResult = { hello: 'world' };
-
-            const handler = LambdaUtils.wrapApiHandler(async (event: APIGatewayEvent): Promise<APIGatewayProxyResult> => {
+            const handler = LambdaUtils.wrapApiHandler(async (event: LambdaUtils.APIGatewayProxyEvent): Promise<APIGatewayProxyResult> => {
                 // Echo the event back
                 return LambdaUtils.apiSuccess(event);
             });
@@ -52,10 +50,10 @@ describe("LambdaUtils", () => {
                 expect(resultEvent.body).toEqual(body);
 
                 // Headers are normalized in request event
-                expect(resultEvent.headers['content-length']).toBeUndefined();
-                expect(resultEvent.headers['Content-Length']).toEqual('0');
+                expect(resultEvent.headers['Content-Length']).toBeUndefined();
+                expect(resultEvent.headers['content-length']).toEqual('0');
                 expect(resultEvent.headers["CONTENT-TYPE"]).toBeUndefined();
-                expect(resultEvent.headers['Content-Type']).toEqual("application/json");
+                expect(resultEvent.headers['content-type']).toEqual("application/json");
 
                 // pathParameters and queryStringParameters are expanded to empty objects
                 expect(resultEvent.pathParameters).toEqual({});
@@ -67,9 +65,7 @@ describe("LambdaUtils", () => {
 
         test("wrapApiHandler promise object success", (endTest) => {
             // GIVEN
-            const expectResult = { hello: 'world' };
-
-            const handler = LambdaUtils.wrapApiHandler(async (event: APIGatewayEvent): Promise<any> => {
+            const handler = LambdaUtils.wrapApiHandler(async (): Promise<any> => {
                 return {message: 'Hello'};
             });
 
@@ -103,9 +99,7 @@ describe("LambdaUtils", () => {
 
         test("wrapApiHandler promise empty success", (endTest) => {
             // GIVEN
-            const expectResult = { hello: 'world' };
-
-            const handler = LambdaUtils.wrapApiHandler(async (event: APIGatewayEvent): Promise<any> => {
+            const handler = LambdaUtils.wrapApiHandler(async (): Promise<any> => {
                 return;
             });
 
@@ -139,7 +133,7 @@ describe("LambdaUtils", () => {
 
         test("wrapApiHandler throw Error", (endTest) => {
             // GIVEN
-            const handler = LambdaUtils.wrapApiHandler(async (event: APIGatewayEvent): Promise<APIGatewayProxyResult> => {
+            const handler = LambdaUtils.wrapApiHandler(async (): Promise<APIGatewayProxyResult> => {
                 throw new Error("oops");
             });
 
@@ -157,7 +151,7 @@ describe("LambdaUtils", () => {
 
         test("wrapApiHandler throw http-error", (endTest) => {
             // GIVEN
-            const handler = LambdaUtils.wrapApiHandler(async (event: APIGatewayEvent): Promise<APIGatewayProxyResult> => {
+            const handler = LambdaUtils.wrapApiHandler(async (): Promise<APIGatewayProxyResult> => {
                 throw new createError.NotFound();
             });
 

lambda-utils/lib/lambda-utils.ts

@@ -4,8 +4,12 @@ import {
     Context,
     ProxyResult
 } from "aws-lambda";
-import * as middy from "middy";
-import {cors, httpEventNormalizer, httpHeaderNormalizer, jsonBodyParser} from "middy/middlewares";
+
+import middy from '@middy/core';
+import cors from '@middy/http-cors';
+import httpEventNormalizer from '@middy/http-event-normalizer';
+import httpHeaderNormalizer from '@middy/http-header-normalizer';
+import httpJsonBodyParser from '@middy/http-json-body-parser';
 import {Logger} from "@sailplane/logger";
 
 const logger = new Logger('lambda-utils');
@@ -40,7 +44,7 @@ export type AsyncProxyHandler = (event: APIGatewayProxyEvent, context: Context)
  * Fine tuned to work better than the Middy version.
  */
 export const unhandledExceptionMiddleware = () => ({
-    onError: (handler: middy.HandlerLambda<APIGatewayEvent,ProxyResult>, next: middy.NextFunction) => {
+    onError: (handler: middy.HandlerLambda<APIGatewayEvent, ProxyResult>, next: middy.NextFunction) => {
 
         logger.error('Unhandled exception:', handler.error);
 
@@ -62,7 +66,7 @@ export const unhandledExceptionMiddleware = () => ({
  * Must be registered as the last (thus first to run) "after" middleware.
  */
 export const resolvedPromiseIsSuccessMiddleware = () => ({
-    after: (handler: middy.HandlerLambda<APIGatewayEvent,ProxyResult>, next: middy.NextFunction) => {
+    after: (handler: middy.HandlerLambda<APIGatewayEvent, ProxyResult>, next: middy.NextFunction) => {
         // If response isn't a proper API result object, convert it into one.
         let r = handler.response;
         if (!r || typeof r !== 'object' || (!r.statusCode && !r.body)) {
@@ -96,9 +100,9 @@ export const resolvedPromiseIsSuccessMiddleware = () => ({
  * @see https://middy.js.org/docs/middlewares.html
  * @see https://www.npmjs.com/package/http-errors
  */
-export function wrapApiHandler(handler: AsyncProxyHandler): middy.Middy<APIGatewayEvent,ProxyResult> {
+export function wrapApiHandler(handler: AsyncProxyHandler): middy.Middy<AWS_APIGatewayProxyEvent, ProxyResult> {
     return middy(handler)
-        .use(httpEventNormalizer()).use(httpHeaderNormalizer()).use(jsonBodyParser())
+        .use(httpEventNormalizer()).use(httpHeaderNormalizer()).use(httpJsonBodyParser())
         .use(cors())
         .use(resolvedPromiseIsSuccessMiddleware())
         .use(unhandledExceptionMiddleware());