[flutter_tools] ensure etag headers are ascii (flutter#55704)

jonahwilliams · web-flow · commit 2aa90166527d · 2020-04-27T15:02:15.000-07:00
diff --git a/packages/flutter_tools/lib/src/build_runner/devfs_web.dart b/packages/flutter_tools/lib/src/build_runner/devfs_web.dart
@@ -350,7 +350,8 @@ class WebAssetServer implements AssetReader {
 
     // For real files, use a serialized file stat plus path as a revision.
     // This allows us to update between canvaskit and non-canvaskit SDKs.
-    final String etag = file.lastModifiedSync().toIso8601String() + file.path;
+    final String etag = file.lastModifiedSync().toIso8601String()
+      + Uri.encodeComponent(file.path);
     if (ifNoneMatch == etag) {
       return shelf.Response.notModified();
     }
diff --git a/packages/flutter_tools/test/general.shard/web/devfs_web_test.dart b/packages/flutter_tools/test/general.shard/web/devfs_web_test.dart
@@ -324,6 +324,18 @@ void main() {
     expect((await response.read().toList()).first, source.readAsBytesSync());
   }));
 
+  test('serves valid etag header for asset files with non-ascii chracters', () => testbed.run(() async {
+    globals.fs.file(globals.fs.path.join('build', 'flutter_assets', 'fooπ'))
+      ..createSync(recursive: true)
+      ..writeAsBytesSync(<int>[1, 2, 3]);
+
+    final Response response = await webAssetServer
+      .handleRequest(Request('GET', Uri.parse('http://foobar/assets/fooπ')));
+    final String etag = response.headers[HttpHeaders.etagHeader];
+
+    expect(etag.runes, everyElement(predicate((int char) => char < 255)));
+  }));
+
   test('handles serving missing asset file', () => testbed.run(() async {
     final Response response = await webAssetServer
       .handleRequest(Request('GET', Uri.parse('http://foobar/assets/foo')));

Original file line number	Diff line number	Diff line change
`@@ -350,7 +350,8 @@ class WebAssetServer implements AssetReader {`
`350`	`350`
`351`	`351`	`// For real files, use a serialized file stat plus path as a revision.`
`352`	`352`	`// This allows us to update between canvaskit and non-canvaskit SDKs.`
`353`		`- final String etag = file.lastModifiedSync().toIso8601String() + file.path;`
	`353`	`+ final String etag = file.lastModifiedSync().toIso8601String()`
	`354`	`+ + Uri.encodeComponent(file.path);`
`354`	`355`	`if (ifNoneMatch == etag) {`
`355`	`356`	`return shelf.Response.notModified();`
`356`	`357`	`}`