1// Copyright 2014 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 "components/component_updater/update_checker.h"
6
7#include <string>
8#include <vector>
9
10#include "base/bind.h"
11#include "base/bind_helpers.h"
12#include "base/compiler_specific.h"
13#include "base/location.h"
14#include "base/logging.h"
15#include "base/macros.h"
16#include "base/memory/scoped_ptr.h"
17#include "base/strings/stringprintf.h"
18#include "base/threading/thread_checker.h"
19#include "components/component_updater/component_updater_configurator.h"
20#include "components/component_updater/component_updater_utils.h"
21#include "components/component_updater/crx_update_item.h"
22#include "components/component_updater/request_sender.h"
23#include "net/url_request/url_fetcher.h"
24#include "url/gurl.h"
25
26namespace component_updater {
27
28namespace {
29
30// Builds an update check request for |components|. |additional_attributes| is
31// serialized as part of the <request> element of the request to customize it
32// with data that is not platform or component specific. For each |item|, a
33// corresponding <app> element is created and inserted as a child node of
34// the <request>.
35//
36// An app element looks like this:
37//    <app appid="hnimpnehoodheedghdeeijklkeaacbdc"
38//         version="0.1.2.3" installsource="ondemand">
39//      <updatecheck />
40//      <packages>
41//        <package fp="abcd" />
42//      </packages>
43//    </app>
44std::string BuildUpdateCheckRequest(const Configurator& config,
45                                    const std::vector<CrxUpdateItem*>& items,
46                                    const std::string& additional_attributes) {
47  std::string app_elements;
48  for (size_t i = 0; i != items.size(); ++i) {
49    const CrxUpdateItem* item = items[i];
50    std::string app("<app ");
51    base::StringAppendF(&app,
52                        "appid=\"%s\" version=\"%s\"",
53                        item->id.c_str(),
54                        item->component.version.GetString().c_str());
55    if (item->on_demand)
56      base::StringAppendF(&app, " installsource=\"ondemand\"");
57    base::StringAppendF(&app, ">");
58    base::StringAppendF(&app, "<updatecheck />");
59    if (!item->component.fingerprint.empty()) {
60      base::StringAppendF(&app,
61                          "<packages>"
62                          "<package fp=\"%s\"/>"
63                          "</packages>",
64                          item->component.fingerprint.c_str());
65    }
66    base::StringAppendF(&app, "</app>");
67    app_elements.append(app);
68    VLOG(1) << "Appending to update request: " << app;
69  }
70
71  return BuildProtocolRequest(config.GetBrowserVersion().GetString(),
72                              config.GetChannel(),
73                              config.GetLang(),
74                              config.GetOSLongName(),
75                              app_elements,
76                              additional_attributes);
77}
78
79class UpdateCheckerImpl : public UpdateChecker {
80 public:
81  explicit UpdateCheckerImpl(const Configurator& config);
82  virtual ~UpdateCheckerImpl();
83
84  // Overrides for UpdateChecker.
85  virtual bool CheckForUpdates(
86      const std::vector<CrxUpdateItem*>& items_to_check,
87      const std::string& additional_attributes,
88      const UpdateCheckCallback& update_check_callback) OVERRIDE;
89
90 private:
91  void OnRequestSenderComplete(const net::URLFetcher* source);
92
93  const Configurator& config_;
94  UpdateCheckCallback update_check_callback_;
95  scoped_ptr<RequestSender> request_sender_;
96
97  base::ThreadChecker thread_checker_;
98
99  DISALLOW_COPY_AND_ASSIGN(UpdateCheckerImpl);
100};
101
102UpdateCheckerImpl::UpdateCheckerImpl(const Configurator& config)
103    : config_(config) {
104}
105
106UpdateCheckerImpl::~UpdateCheckerImpl() {
107  DCHECK(thread_checker_.CalledOnValidThread());
108}
109
110bool UpdateCheckerImpl::CheckForUpdates(
111    const std::vector<CrxUpdateItem*>& items_to_check,
112    const std::string& additional_attributes,
113    const UpdateCheckCallback& update_check_callback) {
114  DCHECK(thread_checker_.CalledOnValidThread());
115
116  if (request_sender_.get()) {
117    NOTREACHED();
118    return false;  // Another update check is in progress.
119  }
120
121  update_check_callback_ = update_check_callback;
122
123  request_sender_.reset(new RequestSender(config_));
124  request_sender_->Send(
125      BuildUpdateCheckRequest(config_, items_to_check, additional_attributes),
126      config_.UpdateUrl(),
127      base::Bind(&UpdateCheckerImpl::OnRequestSenderComplete,
128                 base::Unretained(this)));
129  return true;
130}
131
132void UpdateCheckerImpl::OnRequestSenderComplete(const net::URLFetcher* source) {
133  DCHECK(thread_checker_.CalledOnValidThread());
134
135  const GURL original_url(source->GetOriginalURL());
136  VLOG(1) << "Update check request went to: " << original_url.spec();
137
138  int error = 0;
139  std::string error_message;
140  UpdateResponse update_response;
141
142  if (FetchSuccess(*source)) {
143    std::string xml;
144    source->GetResponseAsString(&xml);
145    if (!update_response.Parse(xml)) {
146      error = -1;
147      error_message = update_response.errors();
148      VLOG(1) << "Update request failed: " << error_message;
149    }
150  } else {
151    error = GetFetchError(*source);
152    error_message.assign("network error");
153    VLOG(1) << "Update request failed: network error";
154  }
155
156  request_sender_.reset();
157  update_check_callback_.Run(
158      original_url, error, error_message, update_response.results());
159}
160
161}  // namespace
162
163scoped_ptr<UpdateChecker> UpdateChecker::Create(const Configurator& config) {
164  return scoped_ptr<UpdateChecker>(new UpdateCheckerImpl(config));
165}
166
167}  // namespace component_updater
168