| // Copyright (c) 2013 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 "chrome/browser/net/connect_interceptor.h" |
| |
| #include "chrome/browser/net/predictor.h" |
| #include "net/base/load_flags.h" |
| #include "net/url_request/url_request.h" |
| |
| namespace chrome_browser_net { |
| |
| ConnectInterceptor::ConnectInterceptor(Predictor* predictor) |
| : timed_cache_(base::TimeDelta::FromSeconds( |
| Predictor::kMaxUnusedSocketLifetimeSecondsWithoutAGet)), |
| predictor_(predictor) { |
| DCHECK(predictor); |
| } |
| |
| ConnectInterceptor::~ConnectInterceptor() { |
| } |
| |
| void ConnectInterceptor::WitnessURLRequest(net::URLRequest* request) { |
| GURL request_scheme_host(Predictor::CanonicalizeUrl(request->url())); |
| if (request_scheme_host == GURL::EmptyGURL()) |
| return; |
| |
| // Learn what URLs are likely to be needed during next startup. |
| predictor_->LearnAboutInitialNavigation(request_scheme_host); |
| |
| bool redirected_host = false; |
| bool is_subresource = !(request->load_flags() & net::LOAD_MAIN_FRAME); |
| if (request->referrer().empty()) { |
| if (request->url() != request->original_url()) { |
| // This request was completed with a redirect. |
| GURL original_scheme_host(request->original_url().GetWithEmptyPath()); |
| if (request_scheme_host != original_scheme_host) { |
| redirected_host = true; |
| // Don't learn from redirects that take path as an argument, but do |
| // learn from short-hand typing entries, such as "cnn.com" redirects to |
| // "www.cnn.com". We can't just check for has_path(), as a mere "/" |
| // will count as a path, so we check that the path is at most a "/" |
| // (1 character long) to decide the redirect is "definitive" and has no |
| // significant path. |
| // TODO(jar): It may be ok to learn from all redirects, as the adaptive |
| // system will not respond until several identical redirects have taken |
| // place. Hence a use of a path (that changes) wouldn't really be |
| // learned from anyway. |
| if (request->original_url().path().length() <= 1 && |
| timed_cache_.WasRecentlySeen(original_scheme_host)) { |
| // TODO(jar): These definite redirects could be learned much faster. |
| predictor_->LearnFromNavigation(original_scheme_host, |
| request_scheme_host); |
| } |
| } |
| } |
| } else { |
| GURL referring_scheme_host = GURL(request->referrer()).GetWithEmptyPath(); |
| // Learn about our referring URL, for use in the future. |
| if (is_subresource && timed_cache_.WasRecentlySeen(referring_scheme_host)) |
| predictor_->LearnFromNavigation(referring_scheme_host, |
| request_scheme_host); |
| if (referring_scheme_host == request_scheme_host) { |
| // We've already made any/all predictions when we navigated to the |
| // referring host, so we can bail out here. |
| // We don't update the RecentlySeen() time because any preconnections |
| // need to be made at the first navigation (i.e., when referer was loaded) |
| // and wouldn't have waited for this current request navigation. |
| return; |
| } |
| } |
| timed_cache_.SetRecentlySeen(request_scheme_host); |
| |
| predictor_->RecordPreconnectNavigationStat(request->url_chain(), |
| is_subresource); |
| |
| // Subresources for main frames usually get predicted when we detected the |
| // main frame request - way back in RenderViewHost::Navigate. So only handle |
| // predictions now for subresources or for redirected hosts. |
| if ((request->load_flags() & net::LOAD_SUB_FRAME) || redirected_host) |
| predictor_->PredictFrameSubresources(request_scheme_host, |
| request->first_party_for_cookies()); |
| return; |
| } |
| |
| } // namespace chrome_browser_net |