Revert "Revert "Use native async/await support in pub.""

sdk/lib/_internal/pub_generated/lib/src/barback/barback_server.dart

Index: sdk/lib/_internal/pub_generated/lib/src/barback/barback_server.dart
diff --git a/sdk/lib/_internal/pub_generated/lib/src/barback/barback_server.dart b/sdk/lib/_internal/pub_generated/lib/src/barback/barback_server.dart
deleted file mode 100644
index 24658e22592e090fdf4139ee289248bc70c63f1d..0000000000000000000000000000000000000000
--- a/sdk/lib/_internal/pub_generated/lib/src/barback/barback_server.dart
+++ /dev/null
@@ -1,211 +0,0 @@
-// Copyright (c) 2013, 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 pub.barback.server;
-
-import 'dart:async';
-import 'dart:io';
-
-import 'package:barback/barback.dart';
-import 'package:mime/mime.dart';
-import 'package:path/path.dart' as path;
-import 'package:shelf/shelf.dart' as shelf;
-import 'package:stack_trace/stack_trace.dart';
-
-import '../barback.dart';
-import '../io.dart';
-import '../log.dart' as log;
-import '../utils.dart';
-import 'base_server.dart';
-import 'asset_environment.dart';
-
-/// Callback for determining if an asset with [id] should be served or not.
-typedef bool AllowAsset(AssetId id);
-
-/// A server that serves assets transformed by barback.
-class BarbackServer extends BaseServer<BarbackServerResult> {
-  /// The package whose assets are being served.
-  final String package;
-
-  /// The directory in the root which will serve as the root of this server as
-  /// a native platform path.
-  ///
-  /// This may be `null` in which case no files in the root package can be
-  /// served and only assets in "lib" directories are available.
-  final String rootDirectory;
-
-  /// Optional callback to determine if an asset should be served.
-  ///
-  /// This can be set to allow outside code to filter out assets. Pub serve
-  /// uses this after plug-ins are loaded to avoid serving ".dart" files in
-  /// release mode.
-  ///
-  /// If this is `null`, all assets may be served.
-  AllowAsset allowAsset;
-
-  /// Creates a new server and binds it to [port] of [host].
-  ///
-  /// This server serves assets from [barback], and uses [rootDirectory]
-  /// (which is relative to the root directory of [package]) as the root
-  /// directory. If [rootDirectory] is omitted, the bound server can only be
-  /// used to serve assets from packages' lib directories (i.e. "packages/..."
-  /// URLs). If [package] is omitted, it defaults to the entrypoint package.
-  static Future<BarbackServer> bind(AssetEnvironment environment, String host,
-      int port, {String package, String rootDirectory}) {
-    if (package == null) package = environment.rootPackage.name;
-    return bindServer(host, port).then((server) {
-      if (rootDirectory == null) {
-        log.fine('Serving packages on $host:$port.');
-      } else {
-        log.fine('Bound "$rootDirectory" to $host:$port.');
-      }
-      return new BarbackServer._(environment, server, package, rootDirectory);
-    });
-  }
-
-  BarbackServer._(AssetEnvironment environment, HttpServer server, this.package,
-      this.rootDirectory)
-      : super(environment, server);
-
-  /// Converts a [url] served by this server into an [AssetId] that can be
-  /// requested from barback.
-  AssetId urlToId(Uri url) {
-    // See if it's a URL to a public directory in a dependency.
-    var id = packagesUrlToId(url);
-    if (id != null) return id;
-
-    if (rootDirectory == null) {
-      throw new FormatException(
-          "This server cannot serve out of the root directory. Got $url.");
-    }
-
-    // Otherwise, it's a path in current package's [rootDirectory].
-    var parts = path.url.split(url.path);
-
-    // Strip the leading "/" from the URL.
-    if (parts.isNotEmpty && parts.first == "/") parts = parts.skip(1);
-
-    var relativePath = path.url.join(rootDirectory, path.url.joinAll(parts));
-    return new AssetId(package, relativePath);
-  }
-
-  /// Handles an HTTP request.
-  handleRequest(shelf.Request request) {
-    if (request.method != "GET" && request.method != "HEAD") {
-      return methodNotAllowed(request);
-    }
-
-    var id;
-    try {
-      id = urlToId(request.url);
-    } on FormatException catch (ex) {
-      // If we got here, we had a path like "/packages" which is a special
-      // directory, but not a valid path since it lacks a following package
-      // name.
-      return notFound(request, error: ex.message);
-    }
-
-    // See if the asset should be blocked.
-    if (allowAsset != null && !allowAsset(id)) {
-      return notFound(
-          request,
-          error: "Asset $id is not available in this configuration.",
-          asset: id);
-    }
-
-    return environment.barback.getAssetById(id).then((result) {
-      return result;
-    }).then((asset) => _serveAsset(request, asset)).catchError((error, trace) {
-      if (error is! AssetNotFoundException) throw error;
-      return environment.barback.getAssetById(
-          id.addExtension("/index.html")).then((asset) {
-        if (request.url.path.endsWith('/')) return _serveAsset(request, asset);
-
-        // We only want to serve index.html if the URL explicitly ends in a
-        // slash. For other URLs, we redirect to one with the slash added to
-        // implicitly support that too. This follows Apache's behavior.
-        logRequest(request, "302 Redirect to ${request.url}/");
-        return new shelf.Response.found('${request.url}/');
-      }).catchError((newError, newTrace) {
-        // If we find neither the original file or the index, we should report
-        // the error about the original to the user.
-        throw newError is AssetNotFoundException ? error : newError;
-      });
-    }).catchError((error, trace) {
-      if (error is! AssetNotFoundException) {
-        trace = new Chain.forTrace(trace);
-        logRequest(request, "$error\n$trace");
-
-        addError(error, trace);
-        close();
-        return new shelf.Response.internalServerError();
-      }
-
-      addResult(new BarbackServerResult._failure(request.url, id, error));
-      return notFound(request, asset: id);
-    }).then((response) {
-      // Allow requests of any origin to access "pub serve". This is useful for
-      // running "pub serve" in parallel with another development server. Since
-      // "pub serve" is only used as a development server and doesn't require
-      // any sort of credentials anyway, this is secure.
-      return response.change(headers: const {
-        "Access-Control-Allow-Origin": "*"
-      });
-    });
-  }
-
-  /// Returns the body of [asset] as a response to [request].
-  Future<shelf.Response> _serveAsset(shelf.Request request, Asset asset) {
-    return validateStream(asset.read()).then((stream) {
-      addResult(new BarbackServerResult._success(request.url, asset.id));
-      var headers = {};
-      var mimeType = lookupMimeType(asset.id.path);
-      if (mimeType != null) headers['Content-Type'] = mimeType;
-      return new shelf.Response.ok(stream, headers: headers);
-    }).catchError((error, trace) {
-      addResult(new BarbackServerResult._failure(request.url, asset.id, error));
-
-      // If we couldn't read the asset, handle the error gracefully.
-      if (error is FileSystemException) {
-        // Assume this means the asset was a file-backed source asset
-        // and we couldn't read it, so treat it like a missing asset.
-        return notFound(request, error: error.toString(), asset: asset.id);
-      }
-
-      trace = new Chain.forTrace(trace);
-      logRequest(request, "$error\n$trace");
-
-      // Otherwise, it's some internal error.
-      return new shelf.Response.internalServerError(body: error.toString());
-    });
-  }
-}
-
-/// The result of the server handling a URL.
-///
-/// Only requests for which an asset was requested from barback will emit a
-/// result. Malformed requests will be handled internally.
-class BarbackServerResult {
-  /// The requested url.
-  final Uri url;
-
-  /// The id that [url] identifies.
-  final AssetId id;
-
-  /// The error thrown by barback.
-  ///
-  /// If the request was served successfully, this will be null.
-  final error;
-
-  /// Whether the request was served successfully.
-  bool get isSuccess => error == null;
-
-  /// Whether the request was served unsuccessfully.
-  bool get isFailure => !isSuccess;
-
-  BarbackServerResult._success(this.url, this.id)
-      : error = null;
-
-  BarbackServerResult._failure(this.url, this.id, this.error);
-}