当使用C++做HTTP客户端时,目前通用的做法就是使用libcurl。其官方网站的地址是http://curl.haxx.se/,该网站主要提供了Curl和libcurl。Curl是命令行工具,用于完成FTP, FTPS, HTTP, HTTPS, GOPHER, TELNET, DICT, FILE 以及 LDAP的命令的请求及接收回馈。libcurl提供给开发者,用于使用C++跨平台的开发各种网络协议的请求及响应。里面的文档非常齐全,不过都是英文的。
本文提供最简单的demo使用libcurl开发HttpClient。主要包括同步的HTTP GET、HTTP POST、HTTPS GET、HTTPS POST。
下载libcurl包,如果使用Linux平台,建议下载源文件编译;如果使用Windows平台,建议下载Win32 - MSVC,下载地址是:http://curl.haxx.se/download.html
- #ifndef __HTTP_CURL_H__
- #define __HTTP_CURL_H__
-
- #include <string>
-
- class CHttpClient
- {
- public:
- CHttpClient(void);
- ~CHttpClient(void);
-
- public:
-
- int Post(const std::string & strUrl, const std::string & strPost, std::string & strResponse);
-
-
- int Get(const std::string & strUrl, std::string & strResponse);
-
-
- int Posts(const std::string & strUrl, const std::string & strPost, std::string & strResponse, const char * pCaPath = NULL);
-
-
- int Gets(const std::string & strUrl, std::string & strResponse, const char * pCaPath = NULL);
-
- public:
- void SetDebug(bool bDebug);
-
- private:
- bool m_bDebug;
- };
-
- #endif
- #include "httpclient.h"
- #include "curl/curl.h"
- #include <string>
-
- CHttpClient::CHttpClient(void) :
- m_bDebug(false)
- {
-
- }
-
- CHttpClient::~CHttpClient(void)
- {
-
- }
-
- static int OnDebug(CURL *, curl_infotype itype, char * pData, size_t size, void *)
- {
- if(itype == CURLINFO_TEXT)
- {
-
- }
- else if(itype == CURLINFO_HEADER_IN)
- {
- printf("[HEADER_IN]%s\n", pData);
- }
- else if(itype == CURLINFO_HEADER_OUT)
- {
- printf("[HEADER_OUT]%s\n", pData);
- }
- else if(itype == CURLINFO_DATA_IN)
- {
- printf("[DATA_IN]%s\n", pData);
- }
- else if(itype == CURLINFO_DATA_OUT)
- {
- printf("[DATA_OUT]%s\n", pData);
- }
- return 0;
- }
-
- static size_t OnWriteData(void* buffer, size_t size, size_t nmemb, void* lpVoid)
- {
- std::string* str = dynamic_cast<std::string*>((std::string *)lpVoid);
- if( NULL == str || NULL == buffer )
- {
- return -1;
- }
-
- char* pData = (char*)buffer;
- str->append(pData, size * nmemb);
- return nmemb;
- }
-
- int CHttpClient::Post(const std::string & strUrl, const std::string & strPost, std::string & strResponse)
- {
- CURLcode res;
- CURL* curl = curl_easy_init();
- if(NULL == curl)
- {
- return CURLE_FAILED_INIT;
- }
- if(m_bDebug)
- {
- curl_easy_setopt(curl, CURLOPT_VERBOSE, 1);
- curl_easy_setopt(curl, CURLOPT_DEBUGFUNCTION, OnDebug);
- }
- curl_easy_setopt(curl, CURLOPT_URL, strUrl.c_str());
- curl_easy_setopt(curl, CURLOPT_POST, 1);
- curl_easy_setopt(curl, CURLOPT_POSTFIELDS, strPost.c_str());
- curl_easy_setopt(curl, CURLOPT_READFUNCTION, NULL);
- curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, OnWriteData);
- curl_easy_setopt(curl, CURLOPT_WRITEDATA, (void *)&strResponse);
- curl_easy_setopt(curl, CURLOPT_NOSIGNAL, 1);
- curl_easy_setopt(curl, CURLOPT_CONNECTTIMEOUT, 3);
- curl_easy_setopt(curl, CURLOPT_TIMEOUT, 3);
- res = curl_easy_perform(curl);
- curl_easy_cleanup(curl);
- return res;
- }
-
- int CHttpClient::Get(const std::string & strUrl, std::string & strResponse)
- {
- CURLcode res;
- CURL* curl = curl_easy_init();
- if(NULL == curl)
- {
- return CURLE_FAILED_INIT;
- }
- if(m_bDebug)
- {
- curl_easy_setopt(curl, CURLOPT_VERBOSE, 1);
- curl_easy_setopt(curl, CURLOPT_DEBUGFUNCTION, OnDebug);
- }
- <pre name="code" class="cpp"> curl_easy_setopt(curl, CURLOPT_URL, strUrl.c_str());
- curl_easy_setopt(curl, CURLOPT_READFUNCTION, NULL);
- curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, OnWriteData);
- curl_easy_setopt(curl, CURLOPT_WRITEDATA, (void *)&strResponse);
-
- curl_easy_setopt(curl, CURLOPT_NOSIGNAL, 1);
- curl_easy_setopt(curl, CURLOPT_CONNECTTIMEOUT, 3);
- curl_easy_setopt(curl, CURLOPT_TIMEOUT, 3);
- res = curl_easy_perform(curl);
- curl_easy_cleanup(curl);
- return res;
- }
-
- int CHttpClient::Posts(const std::string & strUrl, const std::string & strPost, std::string & strResponse, const char * pCaPath)
- {
- CURLcode res;
- CURL* curl = curl_easy_init();
- if(NULL == curl)
- {
- return CURLE_FAILED_INIT;
- }
- if(m_bDebug)
- {
- curl_easy_setopt(curl, CURLOPT_VERBOSE, 1);
- curl_easy_setopt(curl, CURLOPT_DEBUGFUNCTION, OnDebug);
- }
- curl_easy_setopt(curl, CURLOPT_URL, strUrl.c_str());
- curl_easy_setopt(curl, CURLOPT_POST, 1);
- curl_easy_setopt(curl, CURLOPT_POSTFIELDS, strPost.c_str());
- curl_easy_setopt(curl, CURLOPT_READFUNCTION, NULL);
- curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, OnWriteData);
- curl_easy_setopt(curl, CURLOPT_WRITEDATA, (void *)&strResponse);
- curl_easy_setopt(curl, CURLOPT_NOSIGNAL, 1);
- if(NULL == pCaPath)
- {
- curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, false);
- curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, false);
- }
- else
- {
-
-
- curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, true);
- curl_easy_setopt(curl, CURLOPT_CAINFO, pCaPath);
- }
- curl_easy_setopt(curl, CURLOPT_CONNECTTIMEOUT, 3);
- curl_easy_setopt(curl, CURLOPT_TIMEOUT, 3);
- res = curl_easy_perform(curl);
- curl_easy_cleanup(curl);
- return res;
- }
-
- int CHttpClient::Gets(const std::string & strUrl, std::string & strResponse, const char * pCaPath)
- {
- CURLcode res;
- CURL* curl = curl_easy_init();
- if(NULL == curl)
- {
- return CURLE_FAILED_INIT;
- }
- if(m_bDebug)
- {
- curl_easy_setopt(curl, CURLOPT_VERBOSE, 1);
- curl_easy_setopt(curl, CURLOPT_DEBUGFUNCTION, OnDebug);
- }
- curl_easy_setopt(curl, CURLOPT_URL, strUrl.c_str());
- curl_easy_setopt(curl, CURLOPT_READFUNCTION, NULL);
- curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, OnWriteData);
- curl_easy_setopt(curl, CURLOPT_WRITEDATA, (void *)&strResponse);
- curl_easy_setopt(curl, CURLOPT_NOSIGNAL, 1);
- if(NULL == pCaPath)
- {
- curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, false);
- curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, false);
- }
- else
- {
- curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, true);
- curl_easy_setopt(curl, CURLOPT_CAINFO, pCaPath);
- }
- curl_easy_setopt(curl, CURLOPT_CONNECTTIMEOUT, 3);
- curl_easy_setopt(curl, CURLOPT_TIMEOUT, 3);
- res = curl_easy_perform(curl);
- curl_easy_cleanup(curl);
- return res;
- }
-
-
- void CHttpClient::SetDebug(bool bDebug)
- {
- m_bDebug = bDebug;
- }
-