1 //
2 // http_client.cpp
3 // ~~~~~~~~~~~~~~~
4 //
5 // Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
6 //
7 // Distributed under the Boost Software License, Version 1.0. (See accompanying
8 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
9 //
10
11 #include <iostream>
12 #include <istream>
13 #include <ostream>
14 #include <string>
15 #include <boost/asio/ip/tcp.hpp>
16
17 using boost::asio::ip::tcp;
18
main(int argc,char * argv[])19 int main(int argc, char* argv[])
20 {
21 try
22 {
23 if (argc != 3)
24 {
25 std::cout << "Usage: http_client <server> <path>\n";
26 std::cout << "Example:\n";
27 std::cout << " http_client www.boost.org /LICENSE_1_0.txt\n";
28 return 1;
29 }
30
31 boost::asio::ip::tcp::iostream s;
32
33 // The entire sequence of I/O operations must complete within 60 seconds.
34 // If an expiry occurs, the socket is automatically closed and the stream
35 // becomes bad.
36 s.expires_after(std::chrono::seconds(60));
37
38 // Establish a connection to the server.
39 s.connect(argv[1], "http");
40 if (!s)
41 {
42 std::cout << "Unable to connect: " << s.error().message() << "\n";
43 return 1;
44 }
45
46 // Send the request. We specify the "Connection: close" header so that the
47 // server will close the socket after transmitting the response. This will
48 // allow us to treat all data up until the EOF as the content.
49 s << "GET " << argv[2] << " HTTP/1.0\r\n";
50 s << "Host: " << argv[1] << "\r\n";
51 s << "Accept: */*\r\n";
52 s << "Connection: close\r\n\r\n";
53
54 // By default, the stream is tied with itself. This means that the stream
55 // automatically flush the buffered output before attempting a read. It is
56 // not necessary not explicitly flush the stream at this point.
57
58 // Check that response is OK.
59 std::string http_version;
60 s >> http_version;
61 unsigned int status_code;
62 s >> status_code;
63 std::string status_message;
64 std::getline(s, status_message);
65 if (!s || http_version.substr(0, 5) != "HTTP/")
66 {
67 std::cout << "Invalid response\n";
68 return 1;
69 }
70 if (status_code != 200)
71 {
72 std::cout << "Response returned with status code " << status_code << "\n";
73 return 1;
74 }
75
76 // Process the response headers, which are terminated by a blank line.
77 std::string header;
78 while (std::getline(s, header) && header != "\r")
79 std::cout << header << "\n";
80 std::cout << "\n";
81
82 // Write the remaining data to output.
83 std::cout << s.rdbuf();
84 }
85 catch (std::exception& e)
86 {
87 std::cout << "Exception: " << e.what() << "\n";
88 }
89
90 return 0;
91 }
92