chrome/browser/net/net_log_temp_file.h

   1 // Copyright (c) 2013 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_NET_LOG_TEMP_FILE_H_
   6 #define CHROME_BROWSER_NET_NET_LOG_TEMP_FILE_H_
   7
   8 #include <string>
   9
  10 #include "base/basictypes.h"
  11 #include "base/files/file_path.h"
  12 #include "base/gtest_prod_util.h"
  13 #include "base/memory/scoped_ptr.h"
  14
  15 namespace base {
  16 class DictionaryValue;
  17 }
  18
  19 namespace net {
  20 class NetLogLogger;
  21 }
  22
  23 class ChromeNetLog;
  24
  25 // NetLogTempFile logs all the NetLog entries into a temporary file
  26 // "chrome-net-export-log.json" created in base::GetTempDir() directory.
  27 //
  28 // NetLogTempFile maintains the current state (state_) of the logging into a
  29 // chrome-net-export-log.json file.
  30 //
  31 // The following are the possible states
  32 // a) Only Start is allowed (state_ == STATE_UNINITIALIZED).
  33 // b) Only Stop is allowed (state_ == STATE_ALLOW_STOP).
  34 // c) Either Send or Start is allowed (state_ == STATE_ALLOW_START_SEND).
  35 //
  36 // This is created/destroyed on the UI thread, but all other function calls
  37 // occur on the FILE_USER_BLOCKING thread.
  38 //
  39 // This relies on the UI thread outlasting all other named threads for thread
  40 // safety.
  41 class NetLogTempFile {
  42  public:
  43   // This enum lists the UI button commands it could receive.
  44   enum Command {
  45     DO_START,  // Call StartLog.
  46     DO_STOP,   // Call StopLog.
  47   };
  48
  49   virtual ~NetLogTempFile();  // Destructs a NetLogTempFile.
  50
  51   // Accepts the button command and executes it.
  52   void ProcessCommand(Command command);
  53
  54   // Returns true and the path to the temporary file. If there is no file to
  55   // send, then it returns false. It also returns false when actively logging to
  56   // the file.
  57   bool GetFilePath(base::FilePath* path);
  58
  59   // Creates a Value summary of the state of the NetLogTempFile. The caller is
  60   // responsible for deleting the returned value.
  61   base::DictionaryValue* GetState();
  62
  63  protected:
  64   // Constructs a NetLogTempFile. Only one instance is created in browser
  65   // process.
  66   explicit NetLogTempFile(ChromeNetLog* chrome_net_log);
  67
  68   // Returns path name to base::GetTempDir() directory. Returns false if
  69   // base::GetTempDir() fails.
  70   virtual bool GetNetExportLogDirectory(base::FilePath* path);
  71
  72   // Returns true if |log_path_| exists.
  73   virtual bool NetExportLogExists();
  74
  75  private:
  76   friend class ChromeNetLog;
  77   friend class NetLogTempFileTest;
  78
  79   // Allow tests to access our innards for testing purposes.
  80   FRIEND_TEST_ALL_PREFIXES(NetLogTempFileTest, EnsureInitFailure);
  81   FRIEND_TEST_ALL_PREFIXES(NetLogTempFileTest, EnsureInitAllowStart);
  82   FRIEND_TEST_ALL_PREFIXES(NetLogTempFileTest, EnsureInitAllowStartOrSend);
  83   FRIEND_TEST_ALL_PREFIXES(NetLogTempFileTest, ProcessCommandDoStartAndStop);
  84   FRIEND_TEST_ALL_PREFIXES(NetLogTempFileTest, DoStartClearsFile);
  85   FRIEND_TEST_ALL_PREFIXES(NetLogTempFileTest, CheckAddEvent);
  86
  87   // This enum lists the possible state NetLogTempFile could be in. It is used
  88   // to enable/disable "Start", "Stop" and "Send" (email) UI actions.
  89   enum State {
  90     STATE_UNINITIALIZED,
  91     STATE_ALLOW_START,       // Only DO_START Command is allowed.
  92     STATE_ALLOW_STOP,        // Only DO_STOP Command is allowed.
  93     STATE_ALLOW_START_SEND,  // Either DO_START or DO_SEND is allowed.
  94   };
  95
  96   // Initializes the |state_| to either STATE_ALLOW_START (if there is no
  97   // temporary file from earlier run) or STATE_ALLOW_START_SEND (if there is a
  98   // temporary file from earlier run). Returns false if initialization of
  99   // |log_path_| fails.
 100   bool EnsureInit();
 101
 102   // Start collecting NetLog data into chrome-net-export-log.json file in
 103   // base::GetTempDir() directory. It is a no-op if we are already
 104   // collecting data into a file.
 105   void StartNetLog();
 106
 107   // Stop collecting NetLog data into the temporary file. It is a no-op if we
 108   // are not collecting data into a file.
 109   void StopNetLog();
 110
 111   // Updates |log_path_| with base::FilePath to |log_filename_| in the
 112   // base::GetTempDir() directory. Returns false if base::GetTempDir()
 113   // fails.
 114   bool GetNetExportLog();
 115
 116   // Helper function for unit tests.
 117   State state() const { return state_; }
 118
 119   State state_;  // Current state of NetLogTempFile.
 120
 121   // Name of the file. It defaults to chrome-net-export-log.json, but can be
 122   // overwritten by unit tests.
 123   base::FilePath::StringType log_filename_;
 124
 125   base::FilePath log_path_;  // base::FilePath to the temporary file.
 126
 127   // |net_log_logger_| watches the NetLog event stream, and sends all entries to
 128   // the file created in StartNetLog().
 129   scoped_ptr<net::NetLogLogger> net_log_logger_;
 130
 131   // The |chrome_net_log_| is owned by the browser process, cached here to avoid
 132   // using global (g_browser_process).
 133   ChromeNetLog* chrome_net_log_;
 134
 135   DISALLOW_COPY_AND_ASSIGN(NetLogTempFile);
 136 };
 137
 138 #endif  // CHROME_BROWSER_NET_NET_LOG_TEMP_FILE_H_