Pull args, intl, logging, shelf, and source_maps out of the SDK.

pkg/shelf/lib/shelf_io.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.
-
-/// A Shelf adapter for handling [HttpRequest] objects from `dart:io`.
-///
-/// One can provide an instance of [HttpServer] as the `requests` parameter in
-/// [serveRequests].
-///
-/// The `dart:io` adapter supports request hijacking; see [Request.hijack].
-library shelf.io;
-
-import 'dart:async';
-import 'dart:io';
-
-import 'package:stack_trace/stack_trace.dart';
-
-import 'shelf.dart';
-import 'src/util.dart';
-
-/// Starts an [HttpServer] that listens on the specified [address] and
-/// [port] and sends requests to [handler].
-///
-/// See the documentation for [HttpServer.bind] for more details on [address],
-/// [port], and [backlog].
-Future<HttpServer> serve(Handler handler, address, int port,
-    {int backlog}) {
-  if (backlog == null) backlog = 0;
-  return HttpServer.bind(address, port, backlog: backlog).then((server) {
-    serveRequests(server, handler);
-    return server;
-  });
-}
-
-/// Serve a [Stream] of [HttpRequest]s.
-///
-/// [HttpServer] implements [Stream<HttpRequest>] so it can be passed directly
-/// to [serveRequests].
-///
-/// Errors thrown by [handler] while serving a request will be printed to the
-/// console and cause a 500 response with no body. Errors thrown asynchronously
-/// by [handler] will be printed to the console or, if there's an active error
-/// zone, passed to that zone.
-void serveRequests(Stream<HttpRequest> requests, Handler handler) {
-  catchTopLevelErrors(() {
-    requests.listen((request) => handleRequest(request, handler));
-  }, (error, stackTrace) {
-    _logError('Asynchronous error\n$error', stackTrace);
-  });
-}
-
-/// Uses [handler] to handle [request].
-///
-/// Returns a [Future] which completes when the request has been handled.
-Future handleRequest(HttpRequest request, Handler handler) {
-  var shelfRequest;
-  try {
-    shelfRequest = _fromHttpRequest(request);
-  } catch (error, stackTrace) {
-    var response = _logError('Error parsing request.\n$error', stackTrace);
-    return _writeResponse(response, request.response);
-  }
-
-  // TODO(nweiz): abstract out hijack handling to make it easier to implement an
-  // adapter.
-  return syncFuture(() => handler(shelfRequest))
-      .catchError((error, stackTrace) {
-    if (error is HijackException) {
-      // A HijackException should bypass the response-writing logic entirely.
-      if (!shelfRequest.canHijack) throw error;
-
-      // If the request wasn't hijacked, we shouldn't be seeing this exception.
-      return _logError(
-          "Caught HijackException, but the request wasn't hijacked.",
-          stackTrace);
-    }
-
-    return _logError('Error thrown by handler.\n$error', stackTrace);
-  }).then((response) {
-    if (response == null) {
-      response = _logError('null response from handler.');
-    } else if (!shelfRequest.canHijack) {
-      var message = new StringBuffer()
-          ..writeln("Got a response for hijacked request "
-              "${shelfRequest.method} ${shelfRequest.requestedUri}:")
-          ..writeln(response.statusCode);
-      response.headers.forEach((key, value) =>
-          message.writeln("${key}: ${value}"));
-      throw new Exception(message.toString().trim());
-    }
-
-    return _writeResponse(response, request.response);
-  }).catchError((error, stackTrace) {
-    // Ignore HijackExceptions.
-    if (error is! HijackException) throw error;
-  });
-}
-
-/// Creates a new [Request] from the provided [HttpRequest].
-Request _fromHttpRequest(HttpRequest request) {
-  var headers = {};
-  request.headers.forEach((k, v) {
-    // Multiple header values are joined with commas.
-    // See http://tools.ietf.org/html/draft-ietf-httpbis-p1-messaging-21#page-22
-    headers[k] = v.join(',');
-  });
-
-  onHijack(callback) {
-    return request.response.detachSocket(writeHeaders: false)
-        .then((socket) => callback(socket, socket));
-  }
-
-  return new Request(request.method, request.requestedUri,
-      protocolVersion: request.protocolVersion, headers: headers,
-      body: request, onHijack: onHijack);
-}
-
-Future _writeResponse(Response response, HttpResponse httpResponse) {
-  httpResponse.statusCode = response.statusCode;
-
-  response.headers.forEach((header, value) {
-    if (value == null) return;
-    httpResponse.headers.set(header, value);
-  });
-
-  if (!response.headers.containsKey(HttpHeaders.SERVER)) {
-    httpResponse.headers.set(HttpHeaders.SERVER, 'dart:io with Shelf');
-  }
-
-  if (!response.headers.containsKey(HttpHeaders.DATE)) {
-    httpResponse.headers.date = new DateTime.now().toUtc();
-  }
-
-  return httpResponse.addStream(response.read())
-      .then((_) => httpResponse.close());
-}
-
-// TODO(kevmoo) A developer mode is needed to include error info in response
-// TODO(kevmoo) Make error output plugable. stderr, logging, etc
-Response _logError(String message, [StackTrace stackTrace]) {
-  var chain = new Chain.current();
-  if (stackTrace != null) {
-    chain = new Chain.forTrace(stackTrace);
-  }
-  chain = chain
-      .foldFrames((frame) => frame.isCore || frame.package == 'shelf')
-      .terse;
-
-  stderr.writeln('ERROR - ${new DateTime.now()}');
-  stderr.writeln(message);
-  stderr.writeln(chain);
-  return new Response.internalServerError();
-}