Fix headers; Small improvements; Add integration tests;

.gitignore

@@ -60,3 +60,6 @@ typings/
 # dotenv environment variables file
 .env
 
+# IDE
+.idea/
+

integration/__snapshots__/index.test.js.snap

@@ -0,0 +1,25 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`fetches google.com 1`] = `
+Object {
+  "status": 200,
+  "statusText": "OK",
+  "url": "https://www.google.com/",
+}
+`;
+
+exports[`returns error when href is invalid 1`] = `
+Object {
+  "error": Object {
+    "message": "Only absolute URLs are supported",
+  },
+}
+`;
+
+exports[`returns error when href is not passed 1`] = `
+Object {
+  "error": Object {
+    "message": "Cannot read property 'href' of null",
+  },
+}
+`;

integration/index.test.js

@@ -0,0 +1,79 @@
+const childProcess = require('child_process');
+const fetch = require('node-fetch');
+
+let samProcess;
+const port = 5000;
+let lambdaUrl = `http://127.0.0.1:${port}/`;
+function localApiStarted(processOutput) {
+  // Example output when local function started - "Running on http://127.0.0.1:5000/"
+  const urlRegex = /(Running on )(https?:\/\/(www\.)?[-a-zA-Z0-9@:%._\+~#=]{1,256}\.[a-zA-Z0-9()]{1,6}\b([-a-zA-Z0-9()@:%_\+.~#?&//=]*))/gm;
+  const matches = urlRegex.exec(processOutput);
+  return matches && matches.length >= 3;
+}
+
+function startLambda(done) {
+  samProcess = childProcess.spawn(
+    'sam',
+    ['local', 'start-api', '--port', port]
+  );
+  // The runtime output (for example, logs) is output to stderr, and the Lambda function result is output to stdout.
+  // https://docs.aws.amazon.com/serverless-application-model/latest/developerguide/sam-cli-command-reference-sam-local-invoke.html
+  samProcess.stderr.on('data', data => {
+    if (localApiStarted(data.toString())) {
+      done();
+    }
+  });
+  samProcess.on('error', error => {
+    done(new Error(`SAM invoke error: ${error}`));
+  });
+}
+
+function stopLambda() {
+  samProcess.kill();
+}
+
+beforeAll((done) => {
+  startLambda(done);
+});
+
+afterAll(() => {
+  stopLambda();
+});
+
+test('returns error when href is not passed', (done) => {
+  fetch(lambdaUrl)
+    .then(res => {
+      expect(res.status).toEqual(500);
+      return res.json();
+    })
+    .then(res => {
+      expect(res).toMatchSnapshot();
+      done();
+    });
+});
+
+test('returns error when href is invalid', (done) => {
+  const qs = new URLSearchParams({ href: 'google.com' });
+  fetch(`${lambdaUrl}?${qs}`)
+    .then(res => {
+      expect(res.status).toEqual(500);
+      return res.json();
+    })
+    .then(res => {
+      expect(res).toMatchSnapshot();
+      done();
+    });
+});
+
+test('fetches google.com', (done) => {
+  const qs = new URLSearchParams({ href: 'https://google.com' });
+  fetch(`${lambdaUrl}?${qs}`)
+    .then(res => {
+      expect(res.status).toEqual(200);
+      return res.json();
+    })
+    .then(res => {
+      expect(res).toMatchSnapshot();
+      done();
+    });
+});

jest.config.integration.js

@@ -0,0 +1,7 @@
+module.exports = {
+  testEnvironment: 'node',
+  testMatch: [
+    '**/integration/**/*.test.js'
+  ],
+  "rootDir": "./"
+};

jest.config.js

@@ -11,5 +11,9 @@ module.exports = {
     '/node_modules/(?!@)/'
   ],
 
-  "rootDir": "./"
-}
+  "rootDir": "./",
+
+  "modulePathIgnorePatterns": [
+    'integration'
+  ]
+};

package.json

@@ -11,7 +11,9 @@
     "test:debug": "echo '/*' && echo '  Navigate to about:inspect in Chrome' && echo '*/' && node --inspect node_modules/.bin/jest --runInBand",
     "test:ci": "CI=true jest --verbose=false --config ./jest.config.js",
     "test:watch": "jest --watch --verbose=false --config ./jest.config.js",
-    "start": "sam local start-api --port 5000",
+    "test:integration": "npm run build && jest --verbose=false --config ./jest.config.integration.js",
+    "test:watch:integration": "npm run build && jest --watch --verbose=false --config ./jest.config.integration.js",
+    "start": "sam local start-api --port 5000 2>&1 | tr \"\\r\" \"\\n\"",
     "dist": "rm -f dist.zip && zip -jq dist.zip build/index.js",
     "update": "aws lambda update-function-code --function-name FooBarExample --zip-file fileb://dist.zip --publish",
     "deploy": "npm run build && npm run test:ci && npm run dist && npm run update"

src/index.js

@@ -1,29 +1,27 @@
 import fetch from 'node-fetch';
 
-exports.handler = async (event, context, callback) => {
-  // Request headers for a mock 200 response
-  const request = fetch(decodeURIComponent(event.queryStringParameters.href), {
-    method: 'HEAD'
-  });
+function createResponse(statusCode, body) {
+  return {
+    statusCode: statusCode,
+    headers: {'Content-Type': 'application/json'},
+    body: JSON.stringify(body)
+  }
+}
 
-  let data;
+exports.handler = async ({queryStringParameters}, context) => {
+  // TODO: Validate body or query params with some kind of json schema. AJV?
   try {
-    const response = await request;
+    // Request headers for a mock 200 response
+    const response = await fetch(decodeURIComponent(queryStringParameters.href), {
+      method: 'HEAD'
+    });
 
-    data = {
+    return createResponse(200, {
       url: response.url,
       status: response.status,
       statusText: response.statusText
-    };
-  } catch (e) {
-    console.log(e);
+    });
+  } catch (error) {
+    return createResponse(500, {error: {message: error.message}});
   }
-
-  return callback(null, {
-    statusCode: 200,
-    header: {
-      'Content-Type': 'application/json'
-    },
-    body: JSON.stringify(data)
-  });
-}
+};

src/index.test.js

@@ -1,8 +1,6 @@
 import event from '../event.json';
 import { handler } from './index.js';
 
-function callback (error, response) { return error || response }
-
 beforeEach(() => {
   // reset event.json
   jest.resetModules();
@@ -12,10 +10,26 @@ test('Handler does not explode on import', () => {
   expect(true).toBe(true);
 });
 
+test('returns error when href is not provided', async () => {
+  event.queryStringParameters.href = null;
+
+  const response = await handler(event, null);
+
+  expect(response.statusCode).toBe(500);
+});
+
+test('returns error when href is invalid', async () => {
+  event.queryStringParameters.href = 'google.com';
+
+  const response = await handler(event, null);
+
+  expect(response.statusCode).toBe(500);
+});
+
 test('Fetch google.com', async () => {
   event.queryStringParameters.href = encodeURIComponent('https://google.com');
 
-  const response = await handler(event, null, callback)
+  const response = await handler(event, null);
 
   expect(response.statusCode).toBe(200);
-});
+});