spawner_communicator.h revision 1320f92c476a1ad9d19dba2a48c72b75566198e9
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 NET_TEST_SPAWNED_TEST_SERVER_SPAWNER_COMMUNICATOR_H_ 6#define NET_TEST_SPAWNED_TEST_SERVER_SPAWNER_COMMUNICATOR_H_ 7 8#include <string> 9 10#include "base/basictypes.h" 11#include "base/memory/scoped_ptr.h" 12#include "base/memory/weak_ptr.h" 13#include "base/synchronization/waitable_event.h" 14#include "base/threading/thread.h" 15#include "net/url_request/url_request.h" 16 17namespace net { 18 19class ScopedPortException; 20 21// SpawnerCommunicator communicates with a spawner server that runs on a 22// remote system. 23// 24// The test server used by unit tests is written in Python. However, Android 25// does not support running Python code, so the test server cannot run on the 26// same device running unit tests. 27// 28// The actual test server is executed on the host machine, while the unit tests 29// themselves continue running on the device. To control the test server on the 30// host machine, a second HTTP server is started, the spawner server, which 31// controls the life cycle of remote test servers. Calls to start/kill the 32// net::SpawnedTestServer are then redirected to the spawner server via 33// this spawner communicator. 34// 35// Currently only three commands are supported by spawner. 36// 37// (1) Start Python test server, format is: 38// Path: "/start". 39// Method: "POST". 40// Data to server: all arguments needed to launch the Python test server, in 41// JSON format. 42// Data from server: a JSON dict includes the following two field if success, 43// "port": the port the Python test server actually listen on that. 44// "message": must be "started". 45// 46// (2) Kill Python test server, format is: 47// Path: "/kill". 48// Method: "GET". 49// Data to server: None. 50// Data from server: String "killed" returned if success. 51// 52// (3) Ping Python test server to see whether it is alive, format is: 53// Path: "/ping". 54// Method: "GET". 55// Data to server: None. 56// Data from server: String "ready" returned if success. 57// 58// The internal I/O thread is required by net stack to perform net I/O. 59// The Start/StopServer methods block the caller thread until result is 60// fetched from spawner server or timed-out. 61class SpawnerCommunicator : public net::URLRequest::Delegate { 62 public: 63 explicit SpawnerCommunicator(uint16 port); 64 virtual ~SpawnerCommunicator(); 65 66 // Starts an instance of the Python test server on the host/ machine. 67 // If successfully started, returns true, setting |*port| to the port 68 // on the local machine that can be used to communicate with the remote 69 // test server. 70 bool StartServer(const std::string& arguments, 71 uint16* port) WARN_UNUSED_RESULT; 72 73 bool StopServer() WARN_UNUSED_RESULT; 74 75 private: 76 // Starts the IO thread. Called on the user thread. 77 void StartIOThread(); 78 79 // Shuts down the remote test server spawner. Called on the user thread. 80 void Shutdown(); 81 82 // Waits for the server response on IO thread. Called on the user thread. 83 void WaitForResponse(); 84 85 // Sends a command to the test server over HTTP, returning the result code 86 // |*result_code| and response data in |*data_received|, those two arguments 87 // must be not NULL, otherwise the method returns immediately without sending 88 // the |command|. If |post_data| is empty, HTTP GET will be used to send 89 // |command|. If |post_data| is non-empty, performs an HTTP POST. 90 // This method is called on the user thread. 91 void SendCommandAndWaitForResult(const std::string& command, 92 const std::string& post_data, 93 int* result_code, 94 std::string* data_received); 95 96 // Performs the command sending on the IO thread. Called on the IO thread. 97 void SendCommandAndWaitForResultOnIOThread(const std::string& command, 98 const std::string& post_data, 99 int* result_code, 100 std::string* data_received); 101 102 // URLRequest::Delegate methods. Called on the IO thread. 103 virtual void OnResponseStarted(URLRequest* request) OVERRIDE; 104 virtual void OnReadCompleted(URLRequest* request, int num_bytes) OVERRIDE; 105 106 // Reads Result from the response. Called on the IO thread. 107 void ReadResult(URLRequest* request); 108 109 // Called on the IO thread upon completion of the spawner command. 110 void OnSpawnerCommandCompleted(URLRequest* request); 111 112 // Callback on the IO thread for time-out task of request with id |id|. 113 void OnTimeout(int id); 114 115 // A thread to communicate with test_spawner server. 116 base::Thread io_thread_; 117 118 // WaitableEvent to notify whether the communication is done. 119 base::WaitableEvent event_; 120 121 // The local port used to communicate with the TestServer spawner. This is 122 // used to control the startup and shutdown of the Python TestServer running 123 // on the remote machine. On Android, this port will be redirected to the 124 // same port on the host machine. 125 const uint16 port_; 126 127 // Helper to add |port_| to the list of the globally explicitly allowed ports. 128 scoped_ptr<ScopedPortException> allowed_port_; 129 130 // The next ID to use for |cur_request_| (monotonically increasing). 131 int next_id_; 132 133 // Request context used by |cur_request_|. 134 scoped_ptr<URLRequestContext> context_; 135 136 // The current (in progress) request, or NULL. 137 scoped_ptr<URLRequest> cur_request_; 138 139 // Only gets/sets |is_running_| on user's thread to avoid race-condition. 140 bool is_running_; 141 142 // Factory for creating the time-out task. This takes care of revoking 143 // outstanding tasks when |this| is deleted. 144 base::WeakPtrFactory<SpawnerCommunicator> weak_factory_; 145 146 DISALLOW_COPY_AND_ASSIGN(SpawnerCommunicator); 147}; 148 149} // namespace net 150 151#endif // NET_TEST_SPAWNED_TEST_SERVER_SPAWNER_COMMUNICATOR_H_ 152