1 // Copyright 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_FEEDBACK_SYSTEM_LOGS_SYSTEM_LOGS_FETCHER_BASE_H_ 6 #define CHROME_BROWSER_FEEDBACK_SYSTEM_LOGS_SYSTEM_LOGS_FETCHER_BASE_H_ 7 8 #include <map> 9 #include <string> 10 11 #include "base/callback.h" 12 #include "base/memory/scoped_vector.h" 13 #include "base/memory/weak_ptr.h" 14 15 namespace system_logs { 16 17 typedef std::map<std::string, std::string> SystemLogsResponse; 18 19 // Callback that the data sources use to return data. 20 typedef base::Callback<void(SystemLogsResponse* response)> 21 SysLogsSourceCallback; 22 23 // Callback that the SystemLogsFetcherBase uses to return data. 24 typedef base::Callback<void(scoped_ptr<SystemLogsResponse> response)> 25 SysLogsFetcherCallback; 26 27 // The SystemLogsSource provides a interface for the data sources that 28 // the SystemLogsFetcherBase class uses to fetch logs and other 29 // information. 30 class SystemLogsSource { 31 public: 32 // Fetches data and passes it by to the callback 33 virtual void Fetch(const SysLogsSourceCallback& callback) = 0; ~SystemLogsSource()34 virtual ~SystemLogsSource() {} 35 }; 36 37 // The SystemLogsFetcherBaseBase specifies an interface for LogFetcher classes. 38 // Derived LogFetcher classes aggregate the logs from a list of SystemLogSource 39 // classes. 40 // 41 // EXAMPLE: 42 // class Example { 43 // public: 44 // void ProcessLogs(SystemLogsResponse* response) { 45 // //do something with the logs 46 // } 47 // void GetLogs() { 48 // SystemLogsFetcherBase* fetcher = new SystemLogsFetcherBase(); 49 // fetcher->Fetch(base::Bind(&Example::ProcessLogs, this)); 50 // } 51 class SystemLogsFetcherBase 52 : public base::SupportsWeakPtr<SystemLogsFetcherBase> { 53 public: 54 SystemLogsFetcherBase(); 55 ~SystemLogsFetcherBase(); 56 57 void Fetch(const SysLogsFetcherCallback& callback); 58 59 protected: 60 // Callback passed to all the data sources. It merges the |data| it receives 61 // into response_. When all the data sources have responded, it deletes their 62 // objects and returns the response to the callback_. After this it 63 // deletes this instance of the object. 64 void AddResponse(SystemLogsResponse* response); 65 66 ScopedVector<SystemLogsSource> data_sources_; 67 SysLogsFetcherCallback callback_; 68 69 scoped_ptr<SystemLogsResponse> response_; // The actual response data. 70 size_t num_pending_requests_; // The number of callbacks it should get. 71 72 private: 73 74 DISALLOW_COPY_AND_ASSIGN(SystemLogsFetcherBase); 75 }; 76 77 } // namespace system_logs 78 79 #endif // CHROME_BROWSER_FEEDBACK_SYSTEM_LOGS_SYSTEM_LOGS_FETCHER_BASE_H_ 80