reverse index.html implemented

.gitignore

@@ -0,0 +1,7 @@
+node_modules
+.DS_Store
+node_modules
+npm-debug.log
+*.log
+git-commit.json
+.vscode

README.md

@@ -2,6 +2,31 @@
 
 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 ending with a slash (e.g. "/something/") are "internally" redirected to "/something/index.html", i.e. the browser sees "/something/" but on the server-side the content is taken from "/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.
+URIs without an extension (and not ending with a slash) will redirect with an HTTP status 301 (Moved Permanently) to the same URL with a slash appended.
+
+## Examples
+
+  / -> internal redirect -> /index.html
+  /foo/bar/ -> internal redirect -> /foo/bar/index.html
+  /foo -> external redirect (301) -> /foo/
+  /foo.html -> no redirect
+  /foo/bar.html -> no redirect
+  /foo/index.html -> external redirect (301) -> /foo/
+
+## Notes
+
+This URL scheme is somewhat opinionated. It tries to balance SEO requirements with server-side tooling. (E.g. S3 tooling tries to infer the content-type from the file extension.)
+
+It allows you to have very nice outward facing URLs like "/cooltopic", that internally use a file with a correct extension: "cooltopic/index.html". To have content other than index.html in a folder, you need to expose the file extension: "/cooltopic/somecontent.html"
+
+## Installation
+
+1. Create a function called "LATE-standard-redirects-for-cloudfront" in N. Virginia (us-east-1)
+2. Run "npm run deploy"
+
+This function assumes that your CloudFront distribution handles the URL "/" directly by having the property "Default Root Object"
+set to "index.html". 
+
+TODO: IAM, SAM

index.js

@@ -20,13 +20,26 @@ const http = require('http');
 
 exports.handler = (event, context, callback) => {
   const request = event.Records[0].cf.request;
-    
-  if (request.uri.endsWith('/')) {
+  
+  let prefixPath; // needed for 2nd condition
+
+  if (request.uri.match('.+/$')) {
     request.uri += 'index.html';
     callback(null, request);
-  } else if (request.uri.match('/[^/.]*$')) {
+  } else if (prefixPath = request.uri.match('(.+)/index.html')) {
     const response = {
-      status: '302',
+      status: '301',
+      statusDescription: 'Found',
+      headers: {
+        location: [{
+          key: 'Location', value: prefixPath[1] + '/',
+        }],
+      }
+    };
+    callback(null, response);
+  } else if (request.uri.match('/[^/.]+$')) {
+    const response = {
+      status: '301',
       statusDescription: 'Found',
       headers: {
         location: [{

package.json

@@ -0,0 +1,22 @@
+{
+  "name": "standard-redirects-for-cloudfront",
+  "version": "1.0.0",
+  "description": "",
+  "main": "index.js",
+  "scripts": {
+    "test": "mocha",
+    "test-coverage": "istanbul cover _mocha",
+    "predeploy": "git log -1 --pretty=format:'{ \"date\":\"%cI\", \"commit\":\"%H\" }' > git-commit.json",
+    "deploy": "zip -r LATE-standard-redirects-for-cloudfront.zip . -i \\*.js -i git-commit.json -i node_modules/\\* -x test/\\* -x node_modules/aws-sdk/\\* -x node_modules/mocha/\\* && echo Uploading... && aws lambda update-function-code --region us-east-1 --function-name LATE-standard-redirects-for-cloudfront --zip-file fileb://LATE-standard-redirects-for-cloudfront.zip --publish"
+  },
+  "dependencies": {},
+  "license": "Apache-2.0",
+  "author": {
+    "name": "DigitalSailors e.K.",
+    "email": "contact@digital-sailors.de",
+    "url": "https://www.digital-sailors.de"
+  },
+  "devDependencies": {
+    "mocha": "^4.0.1"
+  }
+}

test/unit.js

@@ -0,0 +1,109 @@
+'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 assert = require('assert');
+
+const index = require('../index.js');
+
+describe('Testing index.js', function() {
+  it('/ -> no redirect', function(done) {
+    const event = {
+      Records:[{ cf: {
+          request:  {
+            uri: '/'
+          }
+        } }] };
+    index.handler(event, {}, (err, data) => {
+      done(assert(data.uri === '/'));
+    });
+  });
+
+  it('/foo/ -> internal redirect -> /foo/index.html', function(done) {
+    const event = {
+      Records:[{ cf: {
+          request:  {
+            uri: '/foo/'
+          }
+        } }] };
+    index.handler(event, {}, (err, data) => {
+      done(assert.strictEqual(data.uri, '/foo/index.html'));
+    });
+  });
+
+  it('/foo/bar/ -> internal redirect -> /foo/bar/index.html', function(done) {
+    const event = {
+      Records:[{ cf: {
+          request:  {
+            uri: '/foo/bar/'
+          }
+        } }] };
+    index.handler(event, {}, (err, data) => {
+      done(assert.strictEqual(data.uri, '/foo/bar/index.html'));
+    });
+  });
+  
+  it('/foo -> external redirect (301) -> /foo/', function(done) {
+    const event = {
+      Records:[{ cf: {
+          request:  {
+            uri: '/foo'
+          }
+        } }] };
+    index.handler(event, {}, (err, data) => {
+      done(assert.strictEqual(data.status, '301') 
+          || assert.strictEqual(data.headers.location[0].key, 'Location')
+          || assert.strictEqual(data.headers.location[0].value, '/foo/'));
+    });
+  });
+
+  it('/foo.html -> no redirect', function(done) {
+    const event = {
+      Records:[{ cf: {
+          request:  {
+            uri: '/foo.html'
+          }
+        } }] };
+    index.handler(event, {}, (err, data) => {
+      done(assert.strictEqual(data.uri, '/foo.html'));    });
+  });
+
+  it('/foo/bar.html -> no redirect', function(done) {
+    const event = {
+      Records:[{ cf: {
+          request:  {
+            uri: '/foo/bar.html'
+          }
+        } }] };
+    index.handler(event, {}, (err, data) => {
+      done(assert.strictEqual(data.uri, '/foo/bar.html'));    });
+  });
+
+  it('/foo/index.html -> external redirect (301) -> /foo/', function(done) {
+    const event = {
+      Records:[{ cf: {
+          request:  {
+            uri: '/foo/index.html'
+          }
+        } }] };
+    index.handler(event, {}, (err, data) => {
+      done(assert.strictEqual(data.status, '301') 
+          || assert.strictEqual(data.headers.location[0].key, 'Location')
+          || assert.strictEqual(data.headers.location[0].value, '/foo/'));
+    });
+  });
+});