chrome/browser/net/connection_tester.h

   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 #ifndef CHROME_BROWSER_NET_CONNECTION_TESTER_H_
   6 #define CHROME_BROWSER_NET_CONNECTION_TESTER_H_
   7
   8 #include <vector>
   9
  10 #include "base/basictypes.h"
  11 #include "base/memory/scoped_ptr.h"
  12 #include "net/base/completion_callback.h"
  13 #include "url/gurl.h"
  14
  15 namespace net {
  16 class NetLog;
  17 class URLRequestContext;
  18 }  // namespace net
  19
  20 // ConnectionTester runs a suite of tests (also called "experiments"),
  21 // to try and discover why loading a particular URL is failing with an error
  22 // code.
  23 //
  24 // For example, one reason why the URL might have failed, is that the
  25 // network requires the URL to be routed through a proxy, however chrome is
  26 // not configured for that.
  27 //
  28 // The above issue might be detected by running test that fetches the URL using
  29 // auto-detect and seeing if it works this time. Or even by retrieving the
  30 // settings from another installed browser and trying with those.
  31 //
  32 // USAGE:
  33 //
  34 // To run the test suite, create an instance of ConnectionTester and then call
  35 // RunAllTests().
  36 //
  37 // This starts a sequence of tests, which will complete asynchronously.
  38 // The ConnectionTester object can be deleted at any time, and it will abort
  39 // any of the in-progress tests.
  40 //
  41 // As tests are started or completed, notification will be sent through the
  42 // "Delegate" object.
  43
  44 class ConnectionTester {
  45  public:
  46   // This enum lists the possible proxy settings configurations.
  47   enum ProxySettingsExperiment {
  48     // Do not use any proxy.
  49     PROXY_EXPERIMENT_USE_DIRECT = 0,
  50
  51     // Use the system proxy settings.
  52     PROXY_EXPERIMENT_USE_SYSTEM_SETTINGS,
  53
  54     // Use Firefox's proxy settings if they are available.
  55     PROXY_EXPERIMENT_USE_FIREFOX_SETTINGS,
  56
  57     // Use proxy auto-detect.
  58     PROXY_EXPERIMENT_USE_AUTO_DETECT,
  59
  60     PROXY_EXPERIMENT_COUNT,
  61   };
  62
  63   // This enum lists the possible host resolving configurations.
  64   enum HostResolverExperiment {
  65     // Use a default host resolver implementation.
  66     HOST_RESOLVER_EXPERIMENT_PLAIN = 0,
  67
  68     // Disable IPv6 host resolving.
  69     HOST_RESOLVER_EXPERIMENT_DISABLE_IPV6,
  70
  71     // Probe for IPv6 support.
  72     HOST_RESOLVER_EXPERIMENT_IPV6_PROBE,
  73
  74     HOST_RESOLVER_EXPERIMENT_COUNT,
  75   };
  76
  77   // The "Experiment" structure describes an individual test to run.
  78   struct Experiment {
  79     Experiment(const GURL& url,
  80                ProxySettingsExperiment proxy_settings_experiment,
  81                HostResolverExperiment host_resolver_experiment)
  82         : url(url),
  83           proxy_settings_experiment(proxy_settings_experiment),
  84           host_resolver_experiment(host_resolver_experiment) {
  85     }
  86
  87     // The URL to try and fetch.
  88     GURL url;
  89
  90     // The proxy settings to use.
  91     ProxySettingsExperiment proxy_settings_experiment;
  92
  93     // The host resolver settings to use.
  94     HostResolverExperiment host_resolver_experiment;
  95   };
  96
  97   typedef std::vector<Experiment> ExperimentList;
  98
  99   // "Delegate" is an interface for receiving start and completion notification
 100   // of individual tests that are run by the ConnectionTester.
 101   //
 102   // NOTE: do not delete the ConnectionTester when executing within one of the
 103   // delegate methods.
 104   class Delegate {
 105    public:
 106     // Called once the test suite is about to start.
 107     virtual void OnStartConnectionTestSuite() = 0;
 108
 109     // Called when an individual experiment is about to be started.
 110     virtual void OnStartConnectionTestExperiment(
 111         const Experiment& experiment) = 0;
 112
 113     // Called when an individual experiment has completed.
 114     //   |experiment| - the experiment that has completed.
 115     //   |result| - the net error that the experiment completed with
 116     //              (or net::OK if it was success).
 117     virtual void OnCompletedConnectionTestExperiment(
 118         const Experiment& experiment,
 119         int result) = 0;
 120
 121     // Called once ALL tests have completed.
 122     virtual void OnCompletedConnectionTestSuite() = 0;
 123
 124    protected:
 125     virtual ~Delegate() {}
 126   };
 127
 128   // Constructs a ConnectionTester that notifies test progress to |delegate|.
 129   // |delegate| is owned by the caller, and must remain valid for the lifetime
 130   // of ConnectionTester.
 131   ConnectionTester(Delegate* delegate,
 132                    net::URLRequestContext* proxy_request_context,
 133                    net::NetLog* net_log);
 134
 135   // Note that destruction cancels any in-progress tests.
 136   ~ConnectionTester();
 137
 138   // Starts running the test suite on |url|. Notification of progress is sent to
 139   // |delegate_|.
 140   void RunAllTests(const GURL& url);
 141
 142   // Returns a text string explaining what |experiment| is testing.
 143   static base::string16 ProxySettingsExperimentDescription(
 144       ProxySettingsExperiment experiment);
 145   static base::string16 HostResolverExperimentDescription(
 146       HostResolverExperiment experiment);
 147
 148  private:
 149   // Internally each experiment run by ConnectionTester is handled by a
 150   // "TestRunner" instance.
 151   class TestRunner;
 152   friend class TestRunner;
 153
 154   // Fills |list| with the set of all possible experiments for |url|.
 155   static void GetAllPossibleExperimentCombinations(const GURL& url,
 156                                                    ExperimentList* list);
 157
 158   // Starts the next experiment from |remaining_experiments_|.
 159   void StartNextExperiment();
 160
 161   // Callback for when |current_test_runner_| finishes.
 162   void OnExperimentCompleted(int result);
 163
 164   // Returns the experiment at the front of our list.
 165   const Experiment& current_experiment() const {
 166     return remaining_experiments_.front();
 167   }
 168
 169   // The object to notify test progress to.
 170   Delegate* delegate_;
 171
 172   // The current in-progress test, or NULL if there is no active test.
 173   scoped_ptr<TestRunner> current_test_runner_;
 174
 175   // The ordered list of experiments to try next. The experiment at the front
 176   // of the list is the one currently in progress.
 177   ExperimentList remaining_experiments_;
 178
 179   net::URLRequestContext* const proxy_request_context_;
 180
 181   net::NetLog* net_log_;
 182
 183   DISALLOW_COPY_AND_ASSIGN(ConnectionTester);
 184 };
 185
 186 #endif  // CHROME_BROWSER_NET_CONNECTION_TESTER_H_