JobController 1: Adding a new class HttpStreamFactoryImpl::JobController

net/http/http_stream_factory_impl_job_controller.cc

+// Copyright (c) 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "net/http/http_stream_factory_impl_job_controller.h"
+
+#include "base/strings/string_number_conversions.h"
+#include "base/strings/string_util.h"
+#include "net/base/host_mapping_rules.h"
+#include "net/http/bidirectional_stream_impl.h"
+#include "net/http/http_stream_factory_impl.h"
+#include "net/http/http_stream_factory_impl_job.h"
+#include "net/http/http_stream_factory_impl_request.h"
+#include "net/http/transport_security_state.h"
+#include "net/spdy/spdy_session.h"
+
+namespace net {
+
+HttpStreamFactoryImpl::JobController::JobController(
+    HttpStreamFactoryImpl* factory,
+    HttpStreamRequest::Delegate* delegate,
+    HttpNetworkSession* session)
+    : factory_(factory),
+      session_(session),
+      request_(nullptr),
+      delegate_(delegate),
+      is_preconnect_(false),
+      job_bound_(false),
+      bound_job_(nullptr) {
+  DCHECK(factory);
+}
+
+HttpStreamFactoryImpl::JobController::~JobController() {
+  main_job_.reset();
+  alternative_job_.reset();
+  bound_job_ = nullptr;
+}
+
+bool HttpStreamFactoryImpl::JobController::for_websockets() {
+  return factory_->for_websockets_;
+}
+
+HttpStreamFactoryImpl::Request* HttpStreamFactoryImpl::JobController::Start(
+    const HttpRequestInfo& request_info,
+    HttpStreamRequest::Delegate* delegate,
+    WebSocketHandshakeStreamBase::CreateHelper*
+        websocket_handshake_stream_create_helper,
+    const BoundNetLog& net_log,
+    HttpStreamRequest::StreamType stream_type,
+    RequestPriority priority,
+    const SSLConfig& server_ssl_config,
+    const SSLConfig& proxy_ssl_config) {
+  DCHECK(factory_);
+  DCHECK(!request_);
+
+  request_ = new Request(request_info.url, this, delegate,
+                         websocket_handshake_stream_create_helper, net_log,
+                         stream_type);
+
+  CreateJobs(request_info, priority, server_ssl_config, proxy_ssl_config,
+             delegate, stream_type, net_log);
+
+  return request_;
+}
+
+void HttpStreamFactoryImpl::JobController::Preconnect(
+    int num_streams,
+    const HttpRequestInfo& request_info,
+    const SSLConfig& server_ssl_config,
+    const SSLConfig& proxy_ssl_config) {
+  DCHECK(!main_job_);
+  DCHECK(!alternative_job_);
+
+  is_preconnect_ = true;
+  HostPortPair destination(HostPortPair::FromURL(request_info.url));
+  GURL origin_url = ApplyHostMappingRules(request_info.url, &destination);
+
+  const AlternativeService alternative_service = GetAlternativeServiceFor(
+      request_info, nullptr, HttpStreamRequest::HTTP_STREAM);
+
+  if (alternative_service.protocol != UNINITIALIZED_ALTERNATE_PROTOCOL) {
+    if (session_->params().quic_disable_preconnect_if_0rtt &&
+        alternative_service.protocol == QUIC &&
+        session_->quic_stream_factory()->ZeroRTTEnabledFor(QuicServerId(
+            alternative_service.host_port_pair(), request_info.privacy_mode))) {
+      MaybeNotifyFactoryOfCompletion();
+      return;
+    }
+    destination = alternative_service.host_port_pair();
+    ignore_result(ApplyHostMappingRules(request_info.url, &destination));
+  }
+
+  // Due to how the socket pools handle priorities and idle sockets, only IDLE
+  // priority currently makes sense for preconnects. The priority for
+  // preconnects is currently ignored (see RequestSocketsForPool()), but could
+  // be used at some point for proxy resolution or something.
+  main_job_.reset(new Job(this, PRECONNECT, session_, request_info, IDLE,
+                          server_ssl_config, proxy_ssl_config, destination,
+                          origin_url, alternative_service,
+                          session_->net_log()));
+  main_job_->Preconnect(num_streams);
+}
+
+LoadState HttpStreamFactoryImpl::JobController::GetLoadState() const {
+  DCHECK(request_);
+  if (bound_job_)
+    return bound_job_->GetLoadState();
+
+  // Just pick the first one.
+  return main_job_->GetLoadState();
+}
+
+void HttpStreamFactoryImpl::JobController::OnRequestComplete() {
+  CancelJobs();
+  DCHECK(request_);
+  request_ = nullptr;
+  if (bound_job_) {
+    if (bound_job_->job_type() == MAIN) {
+      main_job_.reset();
+    } else {
+      DCHECK(bound_job_->job_type() == ALTERNATIVE);
+      alternative_job_.reset();
+    }
+    bound_job_ = nullptr;
+  }
+  MaybeNotifyFactoryOfCompletion();
+}
+
+int HttpStreamFactoryImpl::JobController::RestartTunnelWithProxyAuth(
+    const AuthCredentials& credentials) {
+  DCHECK(bound_job_);
+  return bound_job_->RestartTunnelWithProxyAuth(credentials);
+}
+
+void HttpStreamFactoryImpl::JobController::SetPriority(
+    RequestPriority priority) {
+  if (main_job_) {
+    main_job_->SetPriority(priority);
+  }
+  if (alternative_job_) {
+    alternative_job_->SetPriority(priority);
+  }
+}
+
+void HttpStreamFactoryImpl::JobController::OnStreamReady(
+    Job* job,
+    const SSLConfig& used_ssl_config,
+    const ProxyInfo& used_proxy_info) {
+  DCHECK(job);
+
+  if (job_bound_ && bound_job_ != job) {
+    // We have bound a job to the associated Request, |job| has been orphaned.
+    OnOrphanedJobComplete(job);
+    return;
+  }
+  std::unique_ptr<HttpStream> stream = job->GetStream();
+  DCHECK(stream);
+
+  MarkRequestComplete(job->was_npn_negotiated(), job->protocol_negotiated(),
+                      job->using_spdy());
+
+  if (!request_)
+    return;
+  DCHECK(!factory_->for_websockets_);
+  DCHECK_EQ(HttpStreamRequest::HTTP_STREAM, request_->stream_type());
+  OnJobSucceeded(job);
+  request_->OnStreamReady(used_ssl_config, used_proxy_info, stream.release());
+}
+
+void HttpStreamFactoryImpl::JobController::OnBidirectionalStreamImplReady(
+    Job* job,
+    const SSLConfig& used_ssl_config,
+    const ProxyInfo& used_proxy_info) {
+  DCHECK(job);
+
+  if (job_bound_ && bound_job_ != job) {
+    // We have bound a job to the associated Request, |job| has been orphaned.
+    OnOrphanedJobComplete(job);
+    return;
+  }
+
+  MarkRequestComplete(job->was_npn_negotiated(), job->protocol_negotiated(),
+                      job->using_spdy());
+
+  if (!request_)
+    return;
+  std::unique_ptr<BidirectionalStreamImpl> stream =
+      job->GetBidirectionalStream();
+  DCHECK(stream);
+  DCHECK(!factory_->for_websockets_);
+  DCHECK_EQ(HttpStreamRequest::BIDIRECTIONAL_STREAM, request_->stream_type());
+
+  OnJobSucceeded(job);
+  request_->OnBidirectionalStreamImplReady(used_ssl_config, used_proxy_info,
+                                           stream.release());
+}
+
+void HttpStreamFactoryImpl::JobController::OnWebSocketHandshakeStreamReady(
+    Job* job,
+    const SSLConfig& used_ssl_config,
+    const ProxyInfo& used_proxy_info,
+    WebSocketHandshakeStreamBase* stream) {
+  DCHECK(job);
+
+  MarkRequestComplete(job->was_npn_negotiated(), job->protocol_negotiated(),
+                      job->using_spdy());
+
+  if (!request_)
+    return;
+  DCHECK(factory_->for_websockets_);
+  DCHECK_EQ(HttpStreamRequest::HTTP_STREAM, request_->stream_type());
+  DCHECK(stream);
+
+  OnJobSucceeded(job);
+  request_->OnWebSocketHandshakeStreamReady(used_ssl_config, used_proxy_info,
+                                            stream);
+}
+
+void HttpStreamFactoryImpl::JobController::OnStreamFailed(
+    Job* job,
+    int status,
+    const SSLConfig& used_ssl_config,
+    SSLFailureState ssl_failure_state) {
+  if (job_bound_ && bound_job_ != job) {
+    // We have bound a job to the associated Request, |job| has been orphaned.
+    OnOrphanedJobComplete(job);
+    return;
+  }
+
+  if (!request_)
+    return;
+  DCHECK_NE(OK, status);
+  DCHECK(job);
+
+  if (!bound_job_) {
+    if (main_job_ && alternative_job_) {
+      // Hey, we've got other jobs! Maybe one of them will succeed, let's just
+      // ignore this failure.
+      factory_->request_map_.erase(job);
+      // Notify all the other jobs that this one failed.
+      if (job->job_type() == MAIN) {
+        alternative_job_->MarkOtherJobComplete(*job);
+        main_job_.reset();
+      } else {
+        DCHECK(job->job_type() == ALTERNATIVE);
+        main_job_->MarkOtherJobComplete(*job);
+        alternative_job_.reset();
+      }
+      return;
+    } else {
+      BindJob(job);
+    }
+  }
+
+  request_->OnStreamFailed(status, used_ssl_config, ssl_failure_state);
+}
+
+void HttpStreamFactoryImpl::JobController::OnCertificateError(
+    Job* job,
+    int status,
+    const SSLConfig& used_ssl_config,
+    const SSLInfo& ssl_info) {
+  if (job_bound_ && bound_job_ != job) {
+    // We have bound a job to the associated Request, |job| has been orphaned.
+    OnOrphanedJobComplete(job);
+    return;
+  }
+
+  if (!request_)
+    return;
+  DCHECK_NE(OK, status);
+  if (!bound_job_)
+    BindJob(job);
+
+  request_->OnCertificateError(status, used_ssl_config, ssl_info);
+}
+
+void HttpStreamFactoryImpl::JobController::OnHttpsProxyTunnelResponse(
+    Job* job,
+    const HttpResponseInfo& response_info,
+    const SSLConfig& used_ssl_config,
+    const ProxyInfo& used_proxy_info,
+    HttpStream* stream) {
+  if (job_bound_ && bound_job_ != job) {
+    // We have bound a job to the associated Request, |job| has been orphaned.
+    OnOrphanedJobComplete(job);
+    return;
+  }
+
+  if (!bound_job_)
+    BindJob(job);
+  if (!request_)
+    return;
+  request_->OnHttpsProxyTunnelResponse(response_info, used_ssl_config,
+                                       used_proxy_info, stream);
+}
+
+void HttpStreamFactoryImpl::JobController::OnNeedsClientAuth(
+    Job* job,
+    const SSLConfig& used_ssl_config,
+    SSLCertRequestInfo* cert_info) {
+  if (job_bound_ && bound_job_ != job) {
+    // We have bound a job to the associated Request, |job| has been orphaned.
+    OnOrphanedJobComplete(job);
+    return;
+  }
+  if (!request_)
+    return;
+  if (!bound_job_)
+    BindJob(job);
+
+  request_->OnNeedsClientAuth(used_ssl_config, cert_info);
+}
+
+void HttpStreamFactoryImpl::JobController::OnNeedsProxyAuth(
+    Job* job,
+    const HttpResponseInfo& proxy_response,
+    const SSLConfig& used_ssl_config,
+    const ProxyInfo& used_proxy_info,
+    HttpAuthController* auth_controller) {
+  if (job_bound_ && bound_job_ != job) {
+    // We have bound a job to the associated Request, |job| has been orphaned.
+    OnOrphanedJobComplete(job);
+    return;
+  }
+
+  if (!request_)
+    return;
+  if (!bound_job_)
+    BindJob(job);
+  request_->OnNeedsProxyAuth(proxy_response, used_ssl_config, used_proxy_info,
+                             auth_controller);
+}
+
+void HttpStreamFactoryImpl::JobController::OnNewSpdySessionReady(
+    Job* job,
+    const base::WeakPtr<SpdySession>& spdy_session,
+    bool direct) {
+  DCHECK(job);
+  DCHECK(job->using_spdy());
+
+  bool is_job_orphaned = job_bound_ && bound_job_ != job;
+
+  // Cache these values in case the job gets deleted.
+  const SSLConfig used_ssl_config = job->server_ssl_config();
+  const ProxyInfo used_proxy_info = job->proxy_info();
+  const bool was_npn_negotiated = job->was_npn_negotiated();
+  const NextProto protocol_negotiated = job->protocol_negotiated();
+  const bool using_spdy = job->using_spdy();
+  const BoundNetLog net_log = job->net_log();
+
+  // Cache this so we can still use it if the JobController is deleted.
+  HttpStreamFactoryImpl* factory = factory_;
+
+  // Notify |request_|.
+  if (!is_preconnect_ && !is_job_orphaned) {
+    DCHECK(request_);
+
+    // The first case is the usual case.
+    if (!job_bound_) {
+      BindJob(job);
+    }
+
+    MarkRequestComplete(was_npn_negotiated, protocol_negotiated, using_spdy);
+
+    std::unique_ptr<HttpStream> stream;
+    std::unique_ptr<BidirectionalStreamImpl> bidirectional_stream_impl;
+
+    if (for_websockets()) {
+      // TODO(ricea): Re-instate this code when WebSockets over SPDY is
+      // implemented.
+      NOTREACHED();
+    } else if (job->stream_type() == HttpStreamRequest::BIDIRECTIONAL_STREAM) {
+      bidirectional_stream_impl = job->GetBidirectionalStream();
+      DCHECK(bidirectional_stream_impl);
+      delegate_->OnBidirectionalStreamImplReady(
+          used_ssl_config, used_proxy_info,
+          bidirectional_stream_impl.release());
+    } else {
+      stream = job->GetStream();
+      DCHECK(stream);
+      delegate_->OnStreamReady(used_ssl_config, used_proxy_info,
+                               stream.release());
+    }
+  }
+
+  // Notify |factory_|. |request_| and |bounded_job_| might be deleted already.
+  if (spdy_session && spdy_session->IsAvailable()) {
+    factory->OnNewSpdySessionReady(spdy_session, direct, used_ssl_config,
+                                   used_proxy_info, was_npn_negotiated,
+                                   protocol_negotiated, using_spdy, net_log);
+  }
+  if (is_job_orphaned) {
+    OnOrphanedJobComplete(job);
+  }
+}
+
+void HttpStreamFactoryImpl::JobController::OnPreconnectsComplete(Job* job) {
+  DCHECK_EQ(main_job_.get(), job);
+  main_job_.reset();
+  factory_->OnPreconnectsCompleteInternal();
+  MaybeNotifyFactoryOfCompletion();
+}
+
+void HttpStreamFactoryImpl::JobController::OnOrphanedJobComplete(
+    const Job* job) {
+  if (job->job_type() == MAIN) {
+    DCHECK_EQ(main_job_.get(), job);
+    main_job_.reset();
+  } else {
+    DCHECK_EQ(alternative_job_.get(), job);
+    alternative_job_.reset();
+  }
+
+  MaybeNotifyFactoryOfCompletion();
+}
+
+void HttpStreamFactoryImpl::JobController::AddConnectionAttemptsToRequest(
+    Job* job,
+    const ConnectionAttempts& attempts) {
+  if (is_preconnect_ || (job_bound_ && bound_job_ != job))
+    return;
+
+  DCHECK(request_);
+  request_->AddConnectionAttempts(attempts);
+}
+
+void HttpStreamFactoryImpl::JobController::SetSpdySessionKey(
+    Job* job,
+    const SpdySessionKey& spdy_session_key) {
+  if (is_preconnect_ || (job_bound_ && bound_job_ != job))
+    return;
+
+  DCHECK(request_);
+  if (!request_->HasSpdySessionKey()) {
+    RequestSet& request_set =
+        factory_->spdy_session_request_map_[spdy_session_key];
+    DCHECK(!ContainsKey(request_set, request_));
+    request_set.insert(request_);
+    request_->SetSpdySessionKey(spdy_session_key);
+  }
+}
+
+void HttpStreamFactoryImpl::JobController::
+    RemoveRequestFromSpdySessionRequestMapForJob(Job* job) {
+  if (is_preconnect_ || (job_bound_ && bound_job_ != job))
+    return;
+  DCHECK(request_);
+
+  RemoveRequestFromSpdySessionRequestMap();
+}
+
+void HttpStreamFactoryImpl::JobController::
+    RemoveRequestFromSpdySessionRequestMap() {
+  const SpdySessionKey* spdy_session_key = request_->spdy_session_key();
+  if (spdy_session_key) {
+    SpdySessionRequestMap& spdy_session_request_map =
+        factory_->spdy_session_request_map_;
+    DCHECK(ContainsKey(spdy_session_request_map, *spdy_session_key));
+    RequestSet& request_set = spdy_session_request_map[*spdy_session_key];
+    DCHECK(ContainsKey(request_set, request_));
+    request_set.erase(request_);
+    if (request_set.empty())
+      spdy_session_request_map.erase(*spdy_session_key);
+    request_->ResetSpdySessionKey();
+  }
+}
+
+const BoundNetLog* HttpStreamFactoryImpl::JobController::GetNetLog(
+    Job* job) const {
+  if (is_preconnect_ || (job_bound_ && bound_job_ != job))
+    return nullptr;
+  DCHECK(request_);
+  return &request_->net_log();
+}
+
+WebSocketHandshakeStreamBase::CreateHelper* HttpStreamFactoryImpl::
+    JobController::websocket_handshake_stream_create_helper() {
+  DCHECK(request_);
+  return request_->websocket_handshake_stream_create_helper();
+}
+
+void HttpStreamFactoryImpl::JobController::CreateJobs(
+    const HttpRequestInfo& request_info,
+    RequestPriority priority,
+    const SSLConfig& server_ssl_config,
+    const SSLConfig& proxy_ssl_config,
+    HttpStreamRequest::Delegate* delegate,
+    HttpStreamRequest::StreamType stream_type,
+    const BoundNetLog& net_log) {
+  DCHECK(!main_job_);
+  DCHECK(!alternative_job_);
+  HostPortPair destination(HostPortPair::FromURL(request_info.url));
+  GURL origin_url = ApplyHostMappingRules(request_info.url, &destination);
+
+  main_job_.reset(new Job(this, MAIN, session_, request_info, priority,
+                          server_ssl_config, proxy_ssl_config, destination,
+                          origin_url, net_log.net_log()));
+  AttachJob(main_job_.get());
+
+  // Create an alternative job if alternative service is set up for this domain.
+  const AlternativeService alternative_service =
+      GetAlternativeServiceFor(request_info, delegate, stream_type);
+
+  if (alternative_service.protocol != UNINITIALIZED_ALTERNATE_PROTOCOL) {
+    // Never share connection with other jobs for FTP requests.
+    DVLOG(1) << "Selected alternative service (host: "
+             << alternative_service.host_port_pair().host()
+             << " port: " << alternative_service.host_port_pair().port() << ")";
+
+    DCHECK(!request_info.url.SchemeIs("ftp"));
+    HostPortPair alternative_destination(alternative_service.host_port_pair());
+    ignore_result(
+        ApplyHostMappingRules(request_info.url, &alternative_destination));
+
+    alternative_job_.reset(
+        new Job(this, ALTERNATIVE, session_, request_info, priority,
+                server_ssl_config, proxy_ssl_config, alternative_destination,
+                origin_url, alternative_service, net_log.net_log()));
+    AttachJob(alternative_job_.get());
+
+    main_job_->WaitFor(alternative_job_.get());
+    // Make sure to wait until we call WaitFor(), before starting
+    // |alternative_job|, otherwise |alternative_job| will not notify |job|
+    // appropriately.
+    alternative_job_->Start(request_->stream_type());
+  }
+  // Even if |alternative_job| has already finished, it will not have notified
+  // the request yet, since we defer that to the next iteration of the
+  // MessageLoop, so starting |main_job_| is always safe.
+  main_job_->Start(request_->stream_type());
+}
+
+void HttpStreamFactoryImpl::JobController::AttachJob(Job* job) {
+  DCHECK(job);
+  factory_->request_map_[job] = request_;
+}
+
+void HttpStreamFactoryImpl::JobController::BindJob(Job* job) {
+  DCHECK(request_);
+  DCHECK(job);
+  DCHECK(job == alternative_job_.get() || job == main_job_.get());
+  DCHECK(!job_bound_);
+  DCHECK(!bound_job_);
+
+  job_bound_ = true;
+  bound_job_ = job;
+  factory_->request_map_.erase(job);
+
+  request_->net_log().AddEvent(
+      NetLog::TYPE_HTTP_STREAM_REQUEST_BOUND_TO_JOB,
+      job->net_log().source().ToEventParametersCallback());
+  job->net_log().AddEvent(
+      NetLog::TYPE_HTTP_STREAM_JOB_BOUND_TO_REQUEST,
+      request_->net_log().source().ToEventParametersCallback());
+
+  OrphanUnboundJob();
+}
+
+void HttpStreamFactoryImpl::JobController::CancelJobs() {
+  DCHECK(request_);
+  RemoveRequestFromSpdySessionRequestMap();
+  if (job_bound_)
+    return;
+  if (alternative_job_) {
+    factory_->request_map_.erase(alternative_job_.get());
+    alternative_job_.reset();
+  }
+  if (main_job_) {
+    factory_->request_map_.erase(main_job_.get());
+    main_job_.reset();
+  }
+}
+
+void HttpStreamFactoryImpl::JobController::OrphanUnboundJob() {
+  DCHECK(request_);
+  RemoveRequestFromSpdySessionRequestMap();
+
+  DCHECK(bound_job_);
+  if (bound_job_->job_type() == MAIN && alternative_job_) {
+    factory_->request_map_.erase(alternative_job_.get());
+    alternative_job_->Orphan();
+  } else if (bound_job_->job_type() == ALTERNATIVE && main_job_) {
+    // Orphan main job.
+    factory_->request_map_.erase(main_job_.get());
+    main_job_->Orphan();
+  }
+}
+
+void HttpStreamFactoryImpl::JobController::OnJobSucceeded(Job* job) {
+  // |job| should only be nullptr if we're being serviced by a late bound
+  // SpdySession (one that was not created by a job in our |jobs_| set).
+  if (!job) {
+    DCHECK(!bound_job_);
+    // NOTE(willchan): We do *NOT* call OrphanUnboundJob() here. The reason is
+    // because we *WANT* to cancel the unnecessary Jobs from other requests if
+    // another Job completes first.
+    // TODO(mbelshe): Revisit this when we implement ip connection pooling of
+    // SpdySessions. Do we want to orphan the jobs for a different hostname so
+    // they complete? Or do we want to prevent connecting a new SpdySession if
+    // we've already got one available for a different hostname where the ip
+    // address matches up?
+    CancelJobs();
+    return;
+  }
+  if (!bound_job_) {
+    if (main_job_ && alternative_job_) {
+      job->ReportJobSucceededForRequest();
+      // Notify all the other jobs that this one succeeded.
+      if (job->job_type() == MAIN) {
+        alternative_job_->MarkOtherJobComplete(*job);
+      } else {
+        DCHECK(job->job_type() == ALTERNATIVE);
+        main_job_->MarkOtherJobComplete(*job);
+      }
+    }
+    BindJob(job);
+    return;
+  }
+  DCHECK(bound_job_);
+}
+
+void HttpStreamFactoryImpl::JobController::MarkRequestComplete(
+    bool was_npn_negotiated,
+    NextProto protocol_negotiated,
+    bool using_spdy) {
+  if (request_)
+    request_->Complete(was_npn_negotiated, protocol_negotiated, using_spdy);
+}
+
+void HttpStreamFactoryImpl::JobController::MaybeNotifyFactoryOfCompletion() {
+  if (!request_ && !main_job_ && !alternative_job_) {
+    DCHECK(!bound_job_);
+    factory_->OnJobControllerComplete(this);
+  }
+}
+
+GURL HttpStreamFactoryImpl::JobController::ApplyHostMappingRules(
+    const GURL& url,
+    HostPortPair* endpoint) {
+  const HostMappingRules* mapping_rules = session_->params().host_mapping_rules;
+  if (mapping_rules && mapping_rules->RewriteHost(endpoint)) {
+    url::Replacements<char> replacements;
+    const std::string port_str = base::UintToString(endpoint->port());
+    replacements.SetPort(port_str.c_str(), url::Component(0, port_str.size()));
+    replacements.SetHost(endpoint->host().c_str(),
+                         url::Component(0, endpoint->host().size()));
+    return url.ReplaceComponents(replacements);
+  }
+  return url;
+}
+
+bool HttpStreamFactoryImpl::JobController::IsQuicWhitelistedForHost(
+    const std::string& host) {
+  bool whitelist_needed = false;
+  for (QuicVersion version : session_->params().quic_supported_versions) {
+    if (version <= QUIC_VERSION_30) {
+      whitelist_needed = true;
+      break;
+    }
+  }
+
+  // The QUIC whitelist is not needed in QUIC versions after 30.
+  if (!whitelist_needed)
+    return true;
+
+  if (session_->params().transport_security_state->IsGooglePinnedHost(host))
+    return true;
+
+  return ContainsKey(session_->params().quic_host_whitelist,
+                     base::ToLowerASCII(host));
+}
+
+AlternativeService
+HttpStreamFactoryImpl::JobController::GetAlternativeServiceFor(
+    const HttpRequestInfo& request_info,
+    HttpStreamRequest::Delegate* delegate,
+    HttpStreamRequest::StreamType stream_type) {
+  GURL original_url = request_info.url;
+
+  if (original_url.SchemeIs("ftp"))
+    return AlternativeService();
+
+  url::SchemeHostPort origin(original_url);
+  HttpServerProperties& http_server_properties =
+      *session_->http_server_properties();
+  const AlternativeServiceVector alternative_service_vector =
+      http_server_properties.GetAlternativeServices(origin);
+  if (alternative_service_vector.empty())
+    return AlternativeService();
+
+  bool quic_advertised = false;
+  bool quic_all_broken = true;
+
+  const bool enable_different_host =
+      session_->params().enable_alternative_service_with_different_host;
+
+  // First Alt-Svc that is not marked as broken.
+  AlternativeService first_alternative_service;
+
+  for (const AlternativeService& alternative_service :
+       alternative_service_vector) {
+    DCHECK(IsAlternateProtocolValid(alternative_service.protocol));
+    if (!quic_advertised && alternative_service.protocol == QUIC)
+      quic_advertised = true;
+    if (http_server_properties.IsAlternativeServiceBroken(
+            alternative_service)) {
+      HistogramAlternateProtocolUsage(ALTERNATE_PROTOCOL_USAGE_BROKEN);
+      continue;
+    }
+
+    if (origin.host() != alternative_service.host && !enable_different_host)
+      continue;
+
+    // Some shared unix systems may have user home directories (like
+    // http://foo.com/~mike) which allow users to emit headers.  This is a bad
+    // idea already, but with Alternate-Protocol, it provides the ability for a
+    // single user on a multi-user system to hijack the alternate protocol.
+    // These systems also enforce ports <1024 as restricted ports.  So don't
+    // allow protocol upgrades to user-controllable ports.
+    const int kUnrestrictedPort = 1024;
+    if (!session_->params().enable_user_alternate_protocol_ports &&
+        (alternative_service.port >= kUnrestrictedPort &&
+         origin.port() < kUnrestrictedPort))
+      continue;
+
+    if (alternative_service.protocol >= NPN_SPDY_MINIMUM_VERSION &&
+        alternative_service.protocol <= NPN_SPDY_MAXIMUM_VERSION) {
+      if (!HttpStreamFactory::spdy_enabled())
+        continue;
+
+      // Cache this entry if we don't have a non-broken Alt-Svc yet.
+      if (first_alternative_service.protocol ==
+          UNINITIALIZED_ALTERNATE_PROTOCOL)
+        first_alternative_service = alternative_service;
+      continue;
+    }
+
+    DCHECK_EQ(QUIC, alternative_service.protocol);
+    quic_all_broken = false;
+    if (!session_->params().enable_quic)
+      continue;
+
+    if (!IsQuicWhitelistedForHost(origin.host()))
+      continue;
+
+    if (stream_type == HttpStreamRequest::BIDIRECTIONAL_STREAM &&
+        session_->params().quic_disable_bidirectional_streams) {
+      continue;
+    }
+
+    if (session_->quic_stream_factory()->IsQuicDisabled(
+            alternative_service.port))
+      continue;
+
+    if (!original_url.SchemeIs("https"))
+      continue;
+
+    // Check whether there is an existing QUIC session to use for this origin.
+    HostPortPair destination(alternative_service.host_port_pair());
+    ignore_result(ApplyHostMappingRules(original_url, &destination));
+    QuicServerId server_id(destination, request_info.privacy_mode);
+
+    HostPortPair origin_copy(origin.host(), origin.port());
+    ignore_result(ApplyHostMappingRules(original_url, &origin_copy));
+
+    if (session_->quic_stream_factory()->CanUseExistingSession(
+            server_id, origin_copy.host())) {
+      return alternative_service;
+    }
+
+    // Cache this entry if we don't have a non-broken Alt-Svc yet.
+    if (first_alternative_service.protocol == UNINITIALIZED_ALTERNATE_PROTOCOL)
+      first_alternative_service = alternative_service;
+  }
+
+  // Ask delegate to mark QUIC as broken for the origin.
+  if (quic_advertised && quic_all_broken && delegate != nullptr)
+    delegate->OnQuicBroken();
+
+  return first_alternative_service;
+}
+}