src/sync/internal_api/http_bridge.cc

   1 // Copyright 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "sync/internal_api/public/http_bridge.h"
   6
   7 #include "base/message_loop/message_loop.h"
   8 #include "base/message_loop/message_loop_proxy.h"
   9 #include "base/strings/string_number_conversions.h"
  10 #include "net/base/load_flags.h"
  11 #include "net/base/net_errors.h"
  12 #include "net/cookies/cookie_monster.h"
  13 #include "net/dns/host_resolver.h"
  14 #include "net/http/http_cache.h"
  15 #include "net/http/http_network_layer.h"
  16 #include "net/http/http_response_headers.h"
  17 #include "net/proxy/proxy_service.h"
  18 #include "net/url_request/static_http_user_agent_settings.h"
  19 #include "net/url_request/url_fetcher.h"
  20 #include "net/url_request/url_request_context.h"
  21 #include "net/url_request/url_request_status.h"
  22 #include "sync/internal_api/public/base/cancelation_signal.h"
  23
  24 namespace syncer {
  25
  26 HttpBridge::RequestContextGetter::RequestContextGetter(
  27     net::URLRequestContextGetter* baseline_context_getter,
  28     const std::string& user_agent)
  29     : baseline_context_getter_(baseline_context_getter),
  30       network_task_runner_(
  31           baseline_context_getter_->GetNetworkTaskRunner()),
  32       user_agent_(user_agent) {
  33   DCHECK(baseline_context_getter_.get());
  34   DCHECK(network_task_runner_.get());
  35   DCHECK(!user_agent_.empty());
  36 }
  37
  38 HttpBridge::RequestContextGetter::~RequestContextGetter() {}
  39
  40 net::URLRequestContext*
  41 HttpBridge::RequestContextGetter::GetURLRequestContext() {
  42   // Lazily create the context.
  43   if (!context_) {
  44     net::URLRequestContext* baseline_context =
  45         baseline_context_getter_->GetURLRequestContext();
  46     context_.reset(
  47         new RequestContext(baseline_context, GetNetworkTaskRunner(),
  48                            user_agent_));
  49     baseline_context_getter_ = NULL;
  50   }
  51
  52   return context_.get();
  53 }
  54
  55 scoped_refptr<base::SingleThreadTaskRunner>
  56 HttpBridge::RequestContextGetter::GetNetworkTaskRunner() const {
  57   return network_task_runner_;
  58 }
  59
  60 HttpBridgeFactory::HttpBridgeFactory(
  61     net::URLRequestContextGetter* baseline_context_getter,
  62     const NetworkTimeUpdateCallback& network_time_update_callback,
  63     CancelationSignal* cancelation_signal)
  64     : baseline_request_context_getter_(baseline_context_getter),
  65       network_time_update_callback_(network_time_update_callback),
  66       cancelation_signal_(cancelation_signal) {
  67   // Registration should never fail.  This should happen on the UI thread during
  68   // init.  It would be impossible for a shutdown to have been requested at this
  69   // point.
  70   bool result = cancelation_signal_->TryRegisterHandler(this);
  71   DCHECK(result);
  72 }
  73
  74 HttpBridgeFactory::~HttpBridgeFactory() {
  75   cancelation_signal_->UnregisterHandler(this);
  76 }
  77
  78 void HttpBridgeFactory::Init(const std::string& user_agent) {
  79   base::AutoLock lock(context_getter_lock_);
  80
  81   if (!baseline_request_context_getter_.get()) {
  82     // Uh oh.  We've been aborted before we finished initializing.  There's no
  83     // point in initializating further; let's just return right away.
  84     return;
  85   }
  86
  87   request_context_getter_ =
  88       new HttpBridge::RequestContextGetter(
  89           baseline_request_context_getter_, user_agent);
  90 }
  91
  92 HttpPostProviderInterface* HttpBridgeFactory::Create() {
  93   base::AutoLock lock(context_getter_lock_);
  94
  95   // If we've been asked to shut down (something which may happen asynchronously
  96   // and at pretty much any time), then we won't have a request_context_getter_.
  97   // Some external mechanism must ensure that this function is not called after
  98   // we've been asked to shut down.
  99   CHECK(request_context_getter_.get());
 100
 101   HttpBridge* http = new HttpBridge(request_context_getter_.get(),
 102                                     network_time_update_callback_);
 103   http->AddRef();
 104   return http;
 105 }
 106
 107 void HttpBridgeFactory::Destroy(HttpPostProviderInterface* http) {
 108   static_cast<HttpBridge*>(http)->Release();
 109 }
 110
 111 void HttpBridgeFactory::OnSignalReceived() {
 112   base::AutoLock lock(context_getter_lock_);
 113   // Release |baseline_request_context_getter_| as soon as possible so that it
 114   // is destroyed in the right order on its network task runner.  The
 115   // |request_context_getter_| has a reference to the baseline, so we must
 116   // drop our reference to it, too.
 117   baseline_request_context_getter_ = NULL;
 118   request_context_getter_ = NULL;
 119 }
 120
 121 HttpBridge::RequestContext::RequestContext(
 122     net::URLRequestContext* baseline_context,
 123     const scoped_refptr<base::SingleThreadTaskRunner>&
 124         network_task_runner,
 125     const std::string& user_agent)
 126     : baseline_context_(baseline_context),
 127       network_task_runner_(network_task_runner) {
 128   DCHECK(!user_agent.empty());
 129
 130   // Create empty, in-memory cookie store.
 131   set_cookie_store(new net::CookieMonster(NULL, NULL));
 132
 133   // We don't use a cache for bridged loads, but we do want to share proxy info.
 134   set_host_resolver(baseline_context->host_resolver());
 135   set_proxy_service(baseline_context->proxy_service());
 136   set_ssl_config_service(baseline_context->ssl_config_service());
 137
 138   // We want to share the HTTP session data with the network layer factory,
 139   // which includes auth_cache for proxies.
 140   // Session is not refcounted so we need to be careful to not lose the parent
 141   // context.
 142   net::HttpNetworkSession* session =
 143       baseline_context->http_transaction_factory()->GetSession();
 144   DCHECK(session);
 145   set_http_transaction_factory(new net::HttpNetworkLayer(session));
 146
 147   // TODO(timsteele): We don't currently listen for pref changes of these
 148   // fields or CookiePolicy; I'm not sure we want to strictly follow the
 149   // default settings, since for example if the user chooses to block all
 150   // cookies, sync will start failing. Also it seems like accept_lang/charset
 151   // should be tied to whatever the sync servers expect (if anything). These
 152   // fields should probably just be settable by sync backend; though we should
 153   // figure out if we need to give the user explicit control over policies etc.
 154   std::string accepted_language_list;
 155   if (baseline_context->http_user_agent_settings()) {
 156     accepted_language_list =
 157         baseline_context->http_user_agent_settings()->GetAcceptLanguage();
 158   }
 159   http_user_agent_settings_.reset(new net::StaticHttpUserAgentSettings(
 160       accepted_language_list,
 161       user_agent));
 162   set_http_user_agent_settings(http_user_agent_settings_.get());
 163
 164   set_net_log(baseline_context->net_log());
 165 }
 166
 167 HttpBridge::RequestContext::~RequestContext() {
 168   DCHECK(network_task_runner_->BelongsToCurrentThread());
 169   delete http_transaction_factory();
 170 }
 171
 172 HttpBridge::URLFetchState::URLFetchState() : url_poster(NULL),
 173                                              aborted(false),
 174                                              request_completed(false),
 175                                              request_succeeded(false),
 176                                              http_response_code(-1),
 177                                              error_code(-1) {}
 178 HttpBridge::URLFetchState::~URLFetchState() {}
 179
 180 HttpBridge::HttpBridge(
 181     HttpBridge::RequestContextGetter* context_getter,
 182     const NetworkTimeUpdateCallback& network_time_update_callback)
 183     : created_on_loop_(base::MessageLoop::current()),
 184       http_post_completed_(false, false),
 185       context_getter_for_request_(context_getter),
 186       network_task_runner_(
 187           context_getter_for_request_->GetNetworkTaskRunner()),
 188       network_time_update_callback_(network_time_update_callback) {
 189 }
 190
 191 HttpBridge::~HttpBridge() {
 192 }
 193
 194 void HttpBridge::SetExtraRequestHeaders(const char * headers) {
 195   DCHECK(extra_headers_.empty())
 196       << "HttpBridge::SetExtraRequestHeaders called twice.";
 197   extra_headers_.assign(headers);
 198 }
 199
 200 void HttpBridge::SetURL(const char* url, int port) {
 201 #if DCHECK_IS_ON
 202   DCHECK_EQ(base::MessageLoop::current(), created_on_loop_);
 203   {
 204     base::AutoLock lock(fetch_state_lock_);
 205     DCHECK(!fetch_state_.request_completed);
 206   }
 207   DCHECK(url_for_request_.is_empty())
 208       << "HttpBridge::SetURL called more than once?!";
 209 #endif
 210   GURL temp(url);
 211   GURL::Replacements replacements;
 212   std::string port_str = base::IntToString(port);
 213   replacements.SetPort(port_str.c_str(), url::Component(0, port_str.length()));
 214   url_for_request_ = temp.ReplaceComponents(replacements);
 215 }
 216
 217 void HttpBridge::SetPostPayload(const char* content_type,
 218                                 int content_length,
 219                                 const char* content) {
 220 #if DCHECK_IS_ON
 221   DCHECK_EQ(base::MessageLoop::current(), created_on_loop_);
 222   {
 223     base::AutoLock lock(fetch_state_lock_);
 224     DCHECK(!fetch_state_.request_completed);
 225   }
 226   DCHECK(content_type_.empty()) << "Bridge payload already set.";
 227   DCHECK_GE(content_length, 0) << "Content length < 0";
 228 #endif
 229   content_type_ = content_type;
 230   if (!content || (content_length == 0)) {
 231     DCHECK_EQ(content_length, 0);
 232     request_content_ = " ";  // TODO(timsteele): URLFetcher requires non-empty
 233                              // content for POSTs whereas CURL does not, for now
 234                              // we hack this to support the sync backend.
 235   } else {
 236     request_content_.assign(content, content_length);
 237   }
 238 }
 239
 240 bool HttpBridge::MakeSynchronousPost(int* error_code, int* response_code) {
 241 #if DCHECK_IS_ON
 242   DCHECK_EQ(base::MessageLoop::current(), created_on_loop_);
 243   {
 244     base::AutoLock lock(fetch_state_lock_);
 245     DCHECK(!fetch_state_.request_completed);
 246   }
 247   DCHECK(url_for_request_.is_valid()) << "Invalid URL for request";
 248   DCHECK(!content_type_.empty()) << "Payload not set";
 249 #endif
 250
 251   if (!network_task_runner_->PostTask(
 252           FROM_HERE,
 253           base::Bind(&HttpBridge::CallMakeAsynchronousPost, this))) {
 254     // This usually happens when we're in a unit test.
 255     LOG(WARNING) << "Could not post CallMakeAsynchronousPost task";
 256     return false;
 257   }
 258
 259   // Block until network request completes or is aborted. See
 260   // OnURLFetchComplete and Abort.
 261   http_post_completed_.Wait();
 262
 263   base::AutoLock lock(fetch_state_lock_);
 264   DCHECK(fetch_state_.request_completed || fetch_state_.aborted);
 265   *error_code = fetch_state_.error_code;
 266   *response_code = fetch_state_.http_response_code;
 267   return fetch_state_.request_succeeded;
 268 }
 269
 270 void HttpBridge::MakeAsynchronousPost() {
 271   DCHECK(network_task_runner_->BelongsToCurrentThread());
 272   base::AutoLock lock(fetch_state_lock_);
 273   DCHECK(!fetch_state_.request_completed);
 274   if (fetch_state_.aborted)
 275     return;
 276
 277   DCHECK(context_getter_for_request_.get());
 278   fetch_state_.url_poster = net::URLFetcher::Create(
 279       url_for_request_, net::URLFetcher::POST, this);
 280   fetch_state_.url_poster->SetRequestContext(context_getter_for_request_.get());
 281   fetch_state_.url_poster->SetUploadData(content_type_, request_content_);
 282   fetch_state_.url_poster->SetExtraRequestHeaders(extra_headers_);
 283   fetch_state_.url_poster->SetLoadFlags(net::LOAD_DO_NOT_SEND_COOKIES);
 284   fetch_state_.start_time = base::Time::Now();
 285   fetch_state_.url_poster->Start();
 286 }
 287
 288 int HttpBridge::GetResponseContentLength() const {
 289   DCHECK_EQ(base::MessageLoop::current(), created_on_loop_);
 290   base::AutoLock lock(fetch_state_lock_);
 291   DCHECK(fetch_state_.request_completed);
 292   return fetch_state_.response_content.size();
 293 }
 294
 295 const char* HttpBridge::GetResponseContent() const {
 296   DCHECK_EQ(base::MessageLoop::current(), created_on_loop_);
 297   base::AutoLock lock(fetch_state_lock_);
 298   DCHECK(fetch_state_.request_completed);
 299   return fetch_state_.response_content.data();
 300 }
 301
 302 const std::string HttpBridge::GetResponseHeaderValue(
 303     const std::string& name) const {
 304
 305   DCHECK_EQ(base::MessageLoop::current(), created_on_loop_);
 306   base::AutoLock lock(fetch_state_lock_);
 307   DCHECK(fetch_state_.request_completed);
 308
 309   std::string value;
 310   fetch_state_.response_headers->EnumerateHeader(NULL, name, &value);
 311   return value;
 312 }
 313
 314 void HttpBridge::Abort() {
 315   base::AutoLock lock(fetch_state_lock_);
 316
 317   // Release |request_context_getter_| as soon as possible so that it is
 318   // destroyed in the right order on its network task runner.
 319   context_getter_for_request_ = NULL;
 320
 321   DCHECK(!fetch_state_.aborted);
 322   if (fetch_state_.aborted || fetch_state_.request_completed)
 323     return;
 324
 325   fetch_state_.aborted = true;
 326   if (!network_task_runner_->PostTask(
 327           FROM_HERE,
 328           base::Bind(&HttpBridge::DestroyURLFetcherOnIOThread, this,
 329                      fetch_state_.url_poster))) {
 330     // Madness ensues.
 331     NOTREACHED() << "Could not post task to delete URLFetcher";
 332   }
 333
 334   fetch_state_.url_poster = NULL;
 335   fetch_state_.error_code = net::ERR_ABORTED;
 336   http_post_completed_.Signal();
 337 }
 338
 339 void HttpBridge::DestroyURLFetcherOnIOThread(net::URLFetcher* fetcher) {
 340   DCHECK(network_task_runner_->BelongsToCurrentThread());
 341   delete fetcher;
 342 }
 343
 344 void HttpBridge::OnURLFetchComplete(const net::URLFetcher* source) {
 345   DCHECK(network_task_runner_->BelongsToCurrentThread());
 346   base::AutoLock lock(fetch_state_lock_);
 347   if (fetch_state_.aborted)
 348     return;
 349
 350   fetch_state_.end_time = base::Time::Now();
 351   fetch_state_.request_completed = true;
 352   fetch_state_.request_succeeded =
 353       (net::URLRequestStatus::SUCCESS == source->GetStatus().status());
 354   fetch_state_.http_response_code = source->GetResponseCode();
 355   fetch_state_.error_code = source->GetStatus().error();
 356
 357   // Use a real (non-debug) log to facilitate troubleshooting in the wild.
 358   VLOG(2) << "HttpBridge::OnURLFetchComplete for: "
 359           << fetch_state_.url_poster->GetURL().spec();
 360   VLOG(1) << "HttpBridge received response code: "
 361           << fetch_state_.http_response_code;
 362
 363   source->GetResponseAsString(&fetch_state_.response_content);
 364   fetch_state_.response_headers = source->GetResponseHeaders();
 365   UpdateNetworkTime();
 366
 367   // End of the line for url_poster_. It lives only on the IO loop.
 368   // We defer deletion because we're inside a callback from a component of the
 369   // URLFetcher, so it seems most natural / "polite" to let the stack unwind.
 370   base::MessageLoop::current()->DeleteSoon(FROM_HERE, fetch_state_.url_poster);
 371   fetch_state_.url_poster = NULL;
 372
 373   // Wake the blocked syncer thread in MakeSynchronousPost.
 374   // WARNING: DONT DO ANYTHING AFTER THIS CALL! |this| may be deleted!
 375   http_post_completed_.Signal();
 376 }
 377
 378 net::URLRequestContextGetter* HttpBridge::GetRequestContextGetterForTest()
 379     const {
 380   base::AutoLock lock(fetch_state_lock_);
 381   return context_getter_for_request_.get();
 382 }
 383
 384 void HttpBridge::UpdateNetworkTime() {
 385   std::string sane_time_str;
 386   if (!fetch_state_.request_succeeded || fetch_state_.start_time.is_null() ||
 387       fetch_state_.end_time < fetch_state_.start_time ||
 388       !fetch_state_.response_headers->EnumerateHeader(NULL, "Sane-Time-Millis",
 389                                                       &sane_time_str)) {
 390     return;
 391   }
 392
 393   int64 sane_time_ms = 0;
 394   if (base::StringToInt64(sane_time_str, &sane_time_ms)) {
 395     network_time_update_callback_.Run(
 396         base::Time::FromJsTime(sane_time_ms),
 397         base::TimeDelta::FromMilliseconds(1),
 398         fetch_state_.end_time - fetch_state_.start_time);
 399   }
 400 }
 401
 402 }  // namespace syncer