1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
|
/***
* Copyright (C) Microsoft. All rights reserved.
* Licensed under the MIT license. See LICENSE.txt file in the project root for full license information.
*
* =+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+
*
* bingrequest.cpp - Simple cmd line application that makes an HTTP GET request to bing searching and outputting
* the resulting HTML response body into a file.
*
* =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
****/
#include <cpprest/filestream.h>
#include <cpprest/http_client.h>
using namespace utility;
using namespace web::http;
using namespace web::http::client;
using namespace concurrency::streams;
/* Can pass proxy information via environment variable http_proxy.
Example:
Linux: export http_proxy=http://192.1.8.1:8080
*/
web::http::client::http_client_config client_config_for_proxy()
{
web::http::client::http_client_config client_config;
#ifdef _WIN32
wchar_t* pValue = nullptr;
std::unique_ptr<wchar_t, void (*)(wchar_t*)> holder(nullptr, [](wchar_t* p) { free(p); });
size_t len = 0;
auto err = _wdupenv_s(&pValue, &len, L"http_proxy");
if (pValue) holder.reset(pValue);
if (!err && pValue && len)
{
std::wstring env_http_proxy_string(pValue, len - 1);
#else
if (const char* env_http_proxy = std::getenv("http_proxy"))
{
std::string env_http_proxy_string(env_http_proxy);
#endif
if (env_http_proxy_string == U("auto"))
client_config.set_proxy(web::web_proxy::use_auto_discovery);
else
client_config.set_proxy(web::web_proxy(env_http_proxy_string));
}
return client_config;
}
#ifdef _WIN32
int wmain(int argc, wchar_t* args[])
#else
int main(int argc, char* args[])
#endif
{
if (argc != 3)
{
printf("Usage: BingRequest.exe search_term output_file\n");
return -1;
}
const string_t searchTerm = args[1];
const string_t outputFileName = args[2];
// Open a stream to the file to write the HTTP response body into.
auto fileBuffer = std::make_shared<streambuf<uint8_t>>();
file_buffer<uint8_t>::open(outputFileName, std::ios::out)
.then([=](streambuf<uint8_t> outFile) -> pplx::task<http_response> {
*fileBuffer = outFile;
// Create an HTTP request.
// Encode the URI query since it could contain special characters like spaces.
http_client client(U("http://www.bing.com/"), client_config_for_proxy());
return client.request(methods::GET, uri_builder(U("/search")).append_query(U("q"), searchTerm).to_string());
})
// Write the response body into the file buffer.
.then([=](http_response response) -> pplx::task<size_t> {
printf("Response status code %u returned.\n", response.status_code());
return response.body().read_to_end(*fileBuffer);
})
// Close the file buffer.
.then([=](size_t) { return fileBuffer->close(); })
// Wait for the entire response body to be written into the file.
.wait();
return 0;
}
|
