Working version

README.md

@@ -1,2 +1,7 @@
 # standard-redirects-for-cloudfront
-A Lambda@Edge function that implements standard web server redirects
+
+A Lambda@Edge function that implements standard web server redirects:
+
+URIs ending with a slash (e.g. "/something/") are "internally" redirected to "/something/index.html".
+
+URIs without a suffix (and not ending with a slash) will redirect with an HTTP status 301 Moved Permanently to the same URL with a slash appended.

index.js

@@ -0,0 +1,41 @@
+'use strict';
+
+/*
+  Copyright 2017 DigitalSailors e.K.
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+*/
+
+const http = require('http');
+
+exports.handler = (event, context, callback) => {
+  const request = event.Records[0].cf.request;
+    
+  if (request.uri.endsWith('/')) {
+    request.uri += 'index.html';
+    callback(null, request);
+  } else if (request.uri.match('/[^/.]*$')) {
+    const response = {
+      status: '302',
+      statusDescription: 'Found',
+      headers: {
+        location: [{
+          key: 'Location', value: request.uri + '/',
+        }],
+      }
+    };
+    callback(null, response);
+  } else {
+    callback(null, request);
+  }
+}