fix: don't add charset to usdz file type (#357)

Author: gpoitch

lib/middleware.js

@@ -5,6 +5,10 @@ const mime = require('mime');
 const DevMiddlewareError = require('./DevMiddlewareError');
 const { getFilenameFromUrl, handleRangeHeaders, handleRequest, ready } = require('./util');
 
+// Do not add a charset to the Content-Type header of these file types
+// otherwise the client will fail to render them correctly.
+const NonCharsetFileTypes = /\.(wasm|usdz)$/;
+
 module.exports = function wrapper(context) {
   return function middleware(req, res, next) {
     // fixes #282. credit @cexoso. in certain edge situations res.locals is
@@ -71,8 +75,7 @@ module.exports = function wrapper(context) {
 
         let contentType = mime.getType(filename) || '';
 
-        // do not add charset to WebAssembly files, otherwise compileStreaming will fail in the client
-        if (!/\.wasm$/.test(filename)) {
+        if (!NonCharsetFileTypes.test(filename)) {
           contentType += '; charset=UTF-8';
         }
 

test/tests/server.js

@@ -312,17 +312,21 @@ describe('Server', () => {
     });
   });
 
-  describe('WebAssembly', () => {
+  describe('Special file type headers', () => {
     before((done) => {
       app = express();
       const compiler = webpack(webpackConfig);
       instance = middleware(compiler, {
         stats: 'errors-only',
-        logLevel
+        logLevel,
+        mimeTypes: {
+          'model/vnd.pixar.usd': ['usdz']
+        }
       });
       app.use(instance);
       listen = listenShorthand(done);
       instance.fileSystem.writeFileSync('/hello.wasm', 'welcome');
+      instance.fileSystem.writeFileSync('/3dAr.usdz', '010101');
     });
     after(close);
 
@@ -332,6 +336,13 @@ describe('Server', () => {
         .expect('welcome')
         .expect(200, done);
     });
+
+    it('request to 3dAr.usdz', (done) => {
+      request(app).get('/3dAr.usdz')
+        .expect('Content-Type', 'model/vnd.pixar.usd')
+        .expect('010101')
+        .expect(200, done);
+    });
   });
 
   describe('MultiCompiler', () => {