Add appengine/gcloud/mustache dependencies.

pkg/appengine/lib/src/server/assets.dart

+// Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+library appengine.assets;
+
+import 'dart:async';
+import 'dart:io';
+
+import 'package:http_server/http_server.dart' show VirtualDirectory;
+import 'package:path/path.dart' show normalize;
+
+import '../appengine_context.dart';
+import '../client_context.dart';
+
+class AssetsManager {
+  static final root = 'build/web';
+
+  final Uri pubServeUrl;
+  final bool usePubServe;
+  final client = new HttpClient();
+  final VirtualDirectory vd = new VirtualDirectory(root);
+
+  AssetsManager(Uri pubServeUrl, bool isDevEnvironment)
+      : usePubServe = isDevEnvironment && pubServeUrl != null,
+        pubServeUrl = pubServeUrl;
+
+  Future _proxyToPub(HttpRequest request, String path) {
+    const RESPONSE_HEADERS = const [
+        HttpHeaders.CONTENT_LENGTH,
+        HttpHeaders.CONTENT_TYPE ];
+
+    var uri = pubServeUrl.resolve(path);
+    return client.openUrl(request.method, uri)
+        .then((proxyRequest) {
+          proxyRequest.headers.removeAll(HttpHeaders.ACCEPT_ENCODING);
+          return proxyRequest.close();
+        })
+        .then((proxyResponse) {
+          proxyResponse.headers.forEach((name, values) {
+            if (RESPONSE_HEADERS.contains(name)) {
+              request.response.headers.set(name, values);
+            }
+          });
+          request.response.statusCode = proxyResponse.statusCode;
+          request.response.reasonPhrase = proxyResponse.reasonPhrase;
+          return proxyResponse.pipe(request.response);
+        })
+        .catchError((e) {
+          // TODO(kevmoo) Use logging here
+          print("Unable to connect to 'pub serve' for '${request.uri}': $e");
+          throw new AssetError(
+              "Unable to connect to 'pub serve' for '${request.uri}': $e");
+        });
+  }
+
+  Future _serveFromFile(HttpRequest request, String path) {
+    // Check if the request path is pointing to a static resource.
+    path = normalize(path);
+    return FileSystemEntity.isFile(root + path).then((exists) {
+      if (exists) {
+        return vd.serveFile(new File(root + path), request);
+      } else {
+        return _serve404(request);
+      }
+    });
+  }
+
+  Future<Stream<List<int>>> _readFromPub(String path) {
+    var uri = pubServeUrl.resolve(path);
+    return client.openUrl('GET', uri)
+        .then((request) => request.close())
+        .then((response) {
+          if (response.statusCode == HttpStatus.OK) {
+            return response;
+          } else {
+            throw new AssetError(
+                "Failed to fetch asset '$path' from pub: "
+                "${response.statusCode}.");
+          }
+        })
+        .catchError((error) {
+          if (error is! AssetError) {
+            error = new AssetError(
+                "Failed to fetch asset '$path' from pub: '${path}': $error");
+          }
+          throw error;
+        });
+  }
+
+  Future<Stream<List<int>>> _readFromFile(String path) {
+    path = normalize(path);
+    return FileSystemEntity.isFile(root + path).then((exists) {
+      if (exists) {
+        return new File(root + path).openRead();
+      } else {
+        throw new AssetError("Asset '$path' not found");
+      }
+    });
+  }
+
+  Future _serve404(HttpRequest request) {
+    // Serve 404.
+    return request.drain().then((_) {
+      request.response.statusCode = HttpStatus.NOT_FOUND;
+      return request.response.close();
+    });
+  }
+
+  Future<Stream<List<int>>> read(String path) {
+    if (usePubServe) {
+      return _readFromPub(path);
+    } else {
+      return _readFromFile(path);
+    }
+  }
+
+  Future serve(HttpRequest request, String path) {
+    if (usePubServe) {
+      return _proxyToPub(request, path);
+    } else {
+      return _serveFromFile(request, path);
+    }
+  }
+}
+
+class AssetsImpl implements Assets {
+  final HttpRequest request;
+  final AppengineContext appengineContext;
+
+  AssetsImpl(this.request, this.appengineContext);
+
+  Future<Stream<List<int>>> read([String path]) {
+    return appengineContext.assets.read(
+        path == null ? request.uri.path : path);
+  }
+
+  void serve([String path]) {
+    appengineContext.assets.serve(request,
+        path == null ? request.uri.path : path);
+  }
+}