1// Copyright (c) 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 "chrome/browser/renderer_host/offline_resource_throttle.h"
6
7#include <vector>
8
9#include "base/bind.h"
10#include "base/logging.h"
11#include "base/memory/singleton.h"
12#include "base/metrics/histogram.h"
13#include "base/strings/string_util.h"
14#include "chrome/browser/chromeos/offline/offline_load_page.h"
15#include "content/public/browser/appcache_service.h"
16#include "content/public/browser/browser_thread.h"
17#include "content/public/browser/render_view_host.h"
18#include "content/public/browser/resource_controller.h"
19#include "content/public/browser/resource_request_info.h"
20#include "content/public/browser/web_contents.h"
21#include "net/base/net_errors.h"
22#include "net/base/net_util.h"
23#include "net/base/network_change_notifier.h"
24#include "net/url_request/url_request.h"
25#include "net/url_request/url_request_context.h"
26#include "url/url_constants.h"
27
28using content::BrowserThread;
29using content::RenderViewHost;
30using content::WebContents;
31
32namespace {
33
34void ShowOfflinePage(
35    int render_process_id,
36    int render_view_id,
37    const GURL& url,
38    const chromeos::OfflineLoadPage::CompletionCallback& callback) {
39  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
40
41  // Check again on UI thread and proceed if it's connected.
42  if (!net::NetworkChangeNotifier::IsOffline()) {
43    BrowserThread::PostTask(
44        BrowserThread::IO, FROM_HERE, base::Bind(callback, true));
45  } else {
46    RenderViewHost* render_view_host =
47        RenderViewHost::FromID(render_process_id, render_view_id);
48    WebContents* web_contents = render_view_host ?
49        WebContents::FromRenderViewHost(render_view_host) : NULL;
50    // There is a chance that the tab closed after we decided to show
51    // the offline page on the IO thread and before we actually show the
52    // offline page here on the UI thread.
53    if (web_contents)
54      (new chromeos::OfflineLoadPage(web_contents, url, callback))->Show();
55  }
56}
57
58}  // namespace
59
60OfflineResourceThrottle::OfflineResourceThrottle(
61    net::URLRequest* request,
62    content::AppCacheService* appcache_service)
63    : request_(request),
64      appcache_service_(appcache_service) {
65  DCHECK(appcache_service);
66}
67
68OfflineResourceThrottle::~OfflineResourceThrottle() {
69  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
70
71  if (!appcache_completion_callback_.IsCancelled())
72    appcache_completion_callback_.Cancel();
73}
74
75void OfflineResourceThrottle::WillStartRequest(bool* defer) {
76  if (!ShouldShowOfflinePage(request_->url()))
77    return;
78
79  DVLOG(1) << "WillStartRequest: this=" << this << ", url=" << request_->url();
80
81  const GURL* url = &(request_->url());
82  const GURL* first_party = &(request_->first_party_for_cookies());
83
84  // Anticipate a client-side HSTS based redirect from HTTP to HTTPS, and
85  // ask the appcache about the HTTPS url instead of the HTTP url.
86  GURL redirect_url;
87  if (request_->GetHSTSRedirect(&redirect_url)) {
88    if (url->GetOrigin() == first_party->GetOrigin())
89      first_party = &redirect_url;
90    url = &redirect_url;
91  }
92
93  DCHECK(appcache_completion_callback_.IsCancelled());
94
95  appcache_completion_callback_.Reset(
96      base::Bind(&OfflineResourceThrottle::OnCanHandleOfflineComplete,
97                 AsWeakPtr()));
98  appcache_service_->CanHandleMainResourceOffline(
99      *url, *first_party,
100      appcache_completion_callback_.callback());
101
102  *defer = true;
103}
104
105const char* OfflineResourceThrottle::GetNameForLogging() const {
106  return "OfflineResourceThrottle";
107}
108
109void OfflineResourceThrottle::OnBlockingPageComplete(bool proceed) {
110  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
111
112  if (proceed) {
113    controller()->Resume();
114  } else {
115    controller()->Cancel();
116  }
117}
118
119bool OfflineResourceThrottle::IsRemote(const GURL& url) const {
120  return !net::IsLocalhost(url.host()) && (url.SchemeIs(url::kFtpScheme) ||
121                                           url.SchemeIs(url::kHttpScheme) ||
122                                           url.SchemeIs(url::kHttpsScheme));
123}
124
125bool OfflineResourceThrottle::ShouldShowOfflinePage(const GURL& url) const {
126  // If the network is disconnected while loading other resources, we'll simply
127  // show broken link/images.
128  return IsRemote(url) && net::NetworkChangeNotifier::IsOffline();
129}
130
131void OfflineResourceThrottle::OnCanHandleOfflineComplete(int rv) {
132  appcache_completion_callback_.Cancel();
133
134  if (rv == net::OK) {
135    controller()->Resume();
136  } else {
137    const content::ResourceRequestInfo* info =
138        content::ResourceRequestInfo::ForRequest(request_);
139    BrowserThread::PostTask(
140        BrowserThread::UI,
141        FROM_HERE,
142        base::Bind(
143            &ShowOfflinePage,
144            info->GetChildID(),
145            info->GetRouteID(),
146            request_->url(),
147            base::Bind(
148                &OfflineResourceThrottle::OnBlockingPageComplete,
149                AsWeakPtr())));
150  }
151}
152