1 /**
2  * \file HTTPClient.hxx - simple HTTP client engine for SimHear
3  */
4 
5 // Written by James Turner
6 //
7 // Copyright (C) 2013  James Turner  <zakalawe@mac.com>
8 //
9 // This library is free software; you can redistribute it and/or
10 // modify it under the terms of the GNU Library General Public
11 // License as published by the Free Software Foundation; either
12 // version 2 of the License, or (at your option) any later version.
13 //
14 // This library is distributed in the hope that it will be useful,
15 // but WITHOUT ANY WARRANTY; without even the implied warranty of
16 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17 // Library General Public License for more details.
18 //
19 // You should have received a copy of the GNU General Public License
20 // along with this program; if not, write to the Free Software
21 // Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
22 //
23 
24 #ifndef SG_HTTP_CLIENT_HXX
25 #define SG_HTTP_CLIENT_HXX
26 
27 #include <functional>
28 #include <memory>   // for std::unique_ptr
29 #include <stdint.h> // for uint_64t
30 
31 #include <simgear/io/HTTPFileRequest.hxx>
32 #include <simgear/io/HTTPMemoryRequest.hxx>
33 
34 namespace simgear
35 {
36 
37 namespace HTTP
38 {
39 
40 // forward decls
41 class Connection;
42 
43 class Client
44 {
45 public:
46     Client();
47     ~Client();
48 
49     void update(int waitTimeout = 0);
50 
51     void reset();
52 
53     void makeRequest(const Request_ptr& r);
54 
55     void cancelRequest(const Request_ptr& r, std::string reason = std::string());
56 
57     /**
58      * Download a resource and save it to a file.
59      *
60      * @param url       The resource to download
61      * @param filename  Path to the target file
62      * @param data      Data for POST request
63      */
64     FileRequestRef save( const std::string& url,
65                          const std::string& filename );
66 
67     /**
68      * Request a resource and keep it in memory.
69      *
70      * @param url   The resource to download
71      */
72     MemoryRequestRef load(const std::string& url);
73 
74     void setUserAgent(const std::string& ua);
75     void setProxy(const std::string& proxy, int port, const std::string& auth = "");
76 
77     /**
78      * Specify the maximum permitted simultaneous connections
79      * (default value is 1)
80      */
81     void setMaxConnections(unsigned int maxCons);
82 
83     void setMaxHostConnections(unsigned int maxHostConns);
84 
85     /**
86      * maximum depth to pipeline requests - set to 0 to disable pipelining
87      */
88     void setMaxPipelineDepth(unsigned int depth);
89 
90     const std::string& userAgent() const;
91 
92     const std::string& proxyHost() const;
93 
94     const std::string& proxyAuth() const;
95 
96     /**
97      * predicate, check if at least one connection is active, with at
98      * least one request active or queued.
99      */
100     bool hasActiveRequests() const;
101 
102     /**
103      * crude tracking of bytes-per-second transferred over the socket.
104      * suitable for user feedback and rough profiling, nothing more.
105      */
106     unsigned int transferRateBytesPerSec() const;
107 
108     /**
109      * total bytes downloaded by this HTTP client, for bandwidth usage
110      * monitoring
111      */
112     uint64_t totalBytesDownloaded() const;
113 
114     void debugDumpRequests();
115 
116     void clearAllConnections();
117 private:
118     // libCurl callbacks
119     static size_t requestWriteCallback(char *ptr, size_t size, size_t nmemb, void *userdata);
120     static size_t requestReadCallback(char *ptr, size_t size, size_t nmemb, void *userdata);
121     static size_t requestHeaderCallback(char *buffer, size_t size, size_t nitems, void *userdata);
122 
123     void requestFinished(Connection* con);
124 
125     void receivedBytes(unsigned int count);
126 
127     friend class Connection;
128     friend class Request;
129     friend class TestApi;
130 
131     class ClientPrivate;
132     std::unique_ptr<ClientPrivate> d;
133 };
134 
135 } // of namespace HTTP
136 
137 } // of namespace simgear
138 
139 #endif // of SG_HTTP_CLIENT_HXX
140