Added serving of brotli versions of files

closes #76

Author: jtmthf

Readme.md

@@ -22,6 +22,7 @@ $ npm install koa-send
  - `hidden` Allow transfer of hidden files. (defaults to `false`)
  - [`root`](#root-path) Root directory to restrict file access
  - `gzip` Try to serve the gzipped version of a file automatically when `gzip` is supported by a client and if the requested file with `.gz` extension exists. defaults to true.
+ - `brotli` Try to serve the brotli version of a file automatically when `brotli` is supported by a client and if the requested file with `.br` extension exists. defaults to true.
  - `format` If not `false` (defaults to `true`), format the path to serve static file servers and not require a trailing slash for directories, so that you can do both `/directory` and `/directory/`
  - [`setHeaders`](#setheaders) Function to set custom headers on response.
  - `extensions` Try to match extensions from passed array to search for file when no extension is sufficed in URL. First found is served. (defaults to `false`)

index.js

@@ -48,15 +48,14 @@ async function send(ctx, path, opts = {}) {
   const hidden = opts.hidden || false;
   const format = opts.format === false ? false : true;
   const extensions = Array.isArray(opts.extensions) ? opts.extensions : false;
+  const brotli = opts.brotli === false ? false : true;
   const gzip = opts.gzip === false ? false : true;
   const setHeaders = opts.setHeaders;
 
   if (setHeaders && typeof setHeaders !== 'function') {
     throw new TypeError('option setHeaders must be function')
   }
 
-  const encoding = ctx.acceptsEncodings('gzip', 'deflate', 'identity');
-
   // normalize path
   path = decode(path);
 
@@ -70,8 +69,12 @@ async function send(ctx, path, opts = {}) {
   // hidden file support, ignore
   if (!hidden && isHidden(root, path)) return;
 
-  // serve gzipped file when possible
-  if (encoding === 'gzip' && gzip && (await fs.exists(path + '.gz'))) {
+  // serve brotli file when possible otherwise gzipped file when possible
+  if (ctx.acceptsEncodings('br', 'deflate', 'identity') === 'br' && brotli && (await fs.exists(path + '.br'))) {
+    path = path + '.br';
+    ctx.set('Content-Encoding', 'br');
+    ctx.res.removeHeader('Content-Length');
+  } else if (ctx.acceptsEncodings('gzip', 'deflate', 'identity') === 'gzip' && gzip && (await fs.exists(path + '.gz'))) {
     path = path + '.gz';
     ctx.set('Content-Encoding', 'gzip');
     ctx.res.removeHeader('Content-Length');

package.json

@@ -13,6 +13,7 @@
     "index.js"
   ],
   "devDependencies": {
+    "iltorb": "^1.2.1",
     "istanbul": "0",
     "koa": "2",
     "mocha": "3",

test/fixtures/gzip.json.br

@@ -0,0 +1 @@
+��{ "name": "tobi" }

test/index.js

@@ -4,6 +4,7 @@ const send = require('..');
 const path = require('path');
 const Koa = require('koa');
 const assert = require('assert');
+const decompress = require('iltorb').decompress;
 
 describe('send(ctx, file)', function(){
   describe('with no .root', function(){
@@ -372,6 +373,95 @@ describe('send(ctx, file)', function(){
       })
     })
 
+    describe('or .br version when requested and if possible', function(){
+      it('should return path', function(done){
+        const app = new Koa();
+
+        app.use(async (ctx) => {
+          await send(ctx, '/test/fixtures/gzip.json');
+        });
+
+        request(app.listen())
+        .get('/')
+        .set('Accept-Encoding', 'deflate, identity')
+        .expect('Content-Length', '18')
+        .expect('{ "name": "tobi" }')
+        .expect(200, done);
+      })
+
+      it('should return .br path (brotli option defaults to true)', function(done){
+        const app = new Koa();
+
+        app.use(async (ctx) => {
+          await send(ctx, '/test/fixtures/gzip.json');
+        });
+
+        request(app.listen())
+        .get('/')
+        .set('Accept-Encoding', 'br, deflate, identity')
+        .expect('Content-Length', '22')
+        .expect(200)
+        .then(({body}) => {
+          decompress(body, (err, output) => {
+            assert.strictEqual(err, null);
+            assert.deepStrictEqual(output.toString(), '{ "name": "tobi" }');
+            done();
+          });
+        });
+      })
+
+      it('should return .br path when brotli option is turned on', function(done){
+        const app = new Koa();
+
+        app.use(async (ctx) => {
+          await send(ctx, '/test/fixtures/gzip.json', { brotli: true });
+        });
+
+        request(app.listen())
+        .get('/')
+        .set('Accept-Encoding', 'br, deflate, identity')
+        .expect('Content-Length', '22')
+        .expect(200)
+        .then(({body}) => {
+          decompress(body, (err, output) => {
+            assert.strictEqual(err, null);
+            assert.deepStrictEqual(output.toString(), '{ "name": "tobi" }');
+            done();
+          });
+        });
+      })
+
+      it('should not return .br path when brotli option is false', function(done){
+        const app = new Koa();
+
+        app.use(async (ctx) => {
+          await send(ctx, '/test/fixtures/gzip.json', { brotli: false });
+        });
+
+        request(app.listen())
+        .get('/')
+        .set('Accept-Encoding', 'br, deflate, identity')
+        .expect('Content-Length', '18')
+        .expect('{ "name": "tobi" }')
+        .expect(200, done);
+      })
+
+      it('should return .gz path when brotli option is turned off', function(done){
+        const app = new Koa();
+
+        app.use(async (ctx) => {
+          await send(ctx, '/test/fixtures/gzip.json', { brotli: false });
+        });
+
+        request(app.listen())
+        .get('/')
+        .set('Accept-Encoding', 'br, gzip, deflate, identity')
+        .expect('Content-Length', '48')
+        .expect('{ "name": "tobi" }')
+        .expect(200, done);
+      })
+    })
+
     describe('and max age is specified', function(){
       it('should set max-age in seconds', function(done){
         const app = new Koa();