C++下使用libcurl实现微信公众号推送消息到粉丝账号

最近，需要将公司的产品报警信息推送到用户的微信上，之前有过FaceBook和Twitter API使用经验，但真正应用到产品还没有过，今天跑通了原理，记录一下：

入门原理：http://www.360doc.com/content/17/0429/17/30371403_649617749.shtml

为什么选择libcurl呢？因为，微信等的API都是SSL安全https访问，比较过来，就libcurl最简单方便了！！！

闲话不多说，直接上代码，末尾我附上整个VS2013打包工程：

// // 接入微信公众号消息发送API by http://blog.csdn.net/houwenbin1986///// 更多微信公众号API参考：https://mp.weixin.qq.com/debug/////本文档原始来自 http://blog.csdn.net/xulei364132789/article/details/44650757//最近在写一个应用程序, 需要与HTTP服务器进行数据交互, 于是乎自己写了一个类似wget的功能的客户端, //实现很简单, 但是功能不给力, 只可基本功能. 于是又在网上找了找, 发现使用libcurl库很方便, 很强大, //比起wget之类的, 强大不是一点点. //下面是常用的GET/POST/HTTPS/多线程HTTPS的使用方法. 仅仅是一个实现函数. /*************************************************************************** *                                  _   _ ____  _ *  Project                     ___| | | |  _ \| | *                             / __| | | | |_) | | *                            | (__| |_| |  _ <| |___ *                             \___|\___/|_| \_\_____| * * Copyright (C) 1998 - 2011, Daniel Stenberg, <[e-mail]>, et al. * * This software is licensed as described in the file COPYING, which * you should have received as part of this distribution. The terms * are also available at http://curl.haxx.se/docs/copyright.html. * * You may opt to use, copy, modify, merge, publish, distribute and/or sell * copies of the Software, and permit persons to whom the Software is * furnished to do so, under the terms of the COPYING file. * * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY * KIND, either express or implied. * ***************************************************************************//*本文件介绍整curl 库常用的使用方法. 包括GET/POST/UPLOAD/HTTPSby xulei 2015年3月24日 00:15:20    */#include "stdafx.h"#include <stdio.h>#include <stdlib.h>//#include <unistd.h>#include <string.h>#include <fcntl.h>#include <sys/stat.h>#include <sys/types.h>//#include <sys/mman.h>//#include <arpa/inet.h>#include <errno.h>//#include <arpa/inet.h>//#include <semaphore.h> #include <stdarg.h>//#include <pthread.h>#include <signal.h>#include <time.h>//#include <sys/param.h>//#include <getopt.h>#include <direct.h>#include <string>#include <curl/curl.h>#include <openssl/crypto.h>#define curl_printf printf#define CURL_BUF_MAX_LEN  1024#define CURL_NAME_MAX_LEN 512#define CURL_URL_MAX_LEN  1024enum curl_method{CURL_METHOD_GET  = 1,CURL_METHOD_POST = 2,};struct curl_http_args_st{int  curl_method;// curl 方法命令,enum curl_methodchar url[CURL_URL_MAX_LEN];// URL char file_name[CURL_NAME_MAX_LEN];// 返回数据保存为文件FILE *file_fd;// 文件所指向的描述符, 用完后需要手动fcloseint  data_len;// 文件数据保存在内存中的长度char *data;// 文件数据保存在内存中的指针, 用完后手动free char post_data[CURL_BUF_MAX_LEN];// POST 表单数据char post_file[CURL_NAME_MAX_LEN];// POST 文件名};/* we have this global to let the callback get easy access to it *///static pthread_mutex_t *lockarray;////static void lock_callback(int mode, int type, char *file, int line)//{//  (void)file;//  (void)line;//  if (mode & CRYPTO_LOCK) {//    pthread_mutex_lock(&(lockarray[type]));//  }//  else {//    pthread_mutex_unlock(&(lockarray[type]));//  }//}////static unsigned long thread_id(void)//{//  unsigned long ret;////  ret=(unsigned long)pthread_self();//  return(ret);//}////static void init_locks(void)//{//  int i;////  lockarray=(pthread_mutex_t *)OPENSSL_malloc(CRYPTO_num_locks() *//                                            sizeof(pthread_mutex_t));//  for (i=0; i<CRYPTO_num_locks(); i++) {//    pthread_mutex_init(&(lockarray[i]),NULL);//  }////  CRYPTO_set_id_callback((unsigned long (*)())thread_id);//  CRYPTO_set_locking_callback((void (*)())lock_callback);//}////static void kill_locks(void)//{//  int i;////  CRYPTO_set_locking_callback(NULL);//  for (i=0; i<CRYPTO_num_locks(); i++)//    pthread_mutex_destroy(&(lockarray[i]));////  OPENSSL_free(lockarray);//}size_t curl_write_data_cb(void *buffer, size_t size, size_t nmemb, void *stream){int len = size * nmemb;struct curl_http_args_st *args = (struct curl_http_args_st*)stream;if (stream){if (args->file_name[0])// 要写文件{if (!args->file_fd){args->file_fd = fopen(args->file_name, "wb");if (args->file_fd == NULL){curl_printf("%s[%d]: open file[%s] failed!!\n", __FUNCTION__, __LINE__, args->file_name);return 0;}}fwrite(buffer, size, nmemb, args->file_fd);}args->data = (char*)realloc(args->data, args->data_len + len + 1);// 多分配一个字节, 以保存\0 if (!args->data){curl_printf("%s[%d]: realloc failed!!\n", __FUNCTION__, __LINE__);return 0;}memcpy(args->data + args->data_len, buffer, len);args->data_len += len;}return len;}// 创建一个目录，包括其父目录mkdir -p int create_dir(const char *sPathName){char dirname[CURL_NAME_MAX_LEN] = {0};int i, len = strlen(sPathName);//strncpy(dirname, sPathName, sizeof(dirname));//len = strlen(dirname);//for (i = 1; i < len; i++) {//if (dirname[i] == '/') {//dirname[i] = 0;//if (access(dirname, F_OK) != 0) { // 判断是否存在//if (mkdir(dirname, 0777) == -1) {//perror("mkdir  error"); //                   curl_printf("mkdir file: dirname=%s\n", dirname);//return -1;//}//}//dirname[i] = '/';//}//}return 0;}/*http get func */int curl_http_get(struct curl_http_args_st *args){//创建curl对象 CURL *curl; CURLcode return_code;    int ret = -1;// 如果要保存为文件, 先建立文件目录if (args->file_name)    create_dir(args->file_name);    //curl初始化 curl = curl_easy_init(); if (!curl){curl_printf("%s[%d]: curl easy init failed\n", __FUNCTION__, __LINE__);return ret;;}if (strncmp(args->url, "https://", 8) == 0){#if 1// 方法1, 设定为不验证证书和HOSTcurl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 0L);curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 0L);#else// 方法2, 设定一个SSL判别证书, 未测试curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 1L)curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 1L);curl_easy_setopt(curl,CURLOPT_CAINFO,"ca-cert.pem"); // TODO: 设置一个证书文件#endif }curl_easy_setopt(curl,CURLOPT_HEADER,0);//设置httpheader 解析, 不需要将HTTP头写传入回调函数curl_easy_setopt(curl, CURLOPT_URL,args->url);//设置远端地址 curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L);// TODO: 打开调试信息curl_easy_setopt(curl,CURLOPT_FOLLOWLOCATION,1);//设置允许302  跳转curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, curl_write_data_cb); //执行写入文件流操作 的回调函数curl_easy_setopt(curl, CURLOPT_WRITEDATA, args);// 设置回调函数的第4 个参数        curl_easy_setopt(curl, CURLOPT_IPRESOLVE, CURL_IPRESOLVE_V4);//设置为ipv4类型curl_easy_setopt(curl, CURLOPT_CONNECTTIMEOUT, 30); //设置连接超时，单位s, CURLOPT_CONNECTTIMEOUT_MS 毫秒// curl_easy_setopt(curl,CURLOPT_TIMEOUT, 5);// 整个CURL 执行的时间, 单位秒, CURLOPT_TIMEOUT_MS毫秒curl_easy_setopt(curl, CURLOPT_NOSIGNAL, 1);//linux多线程情况应注意的设置(防止curl被alarm信号干扰)return_code = curl_easy_perform(curl); if (CURLE_OK != return_code){curl_printf("curl_easy_perform() failed: %s\n", curl_easy_strerror(return_code));ret  = 0;}if (args->file_fd)// 若需要再次处理写入的文件, 在此可以直接使用{ //关闭文件流fclose(args->file_fd); } if (args->data)// 若要对返回的内容进行处理, 可在此处理{curl_printf("data_len:%d\n%s\n", args->data_len, args->data);//打印到终端free(args->data);args->data = NULL;}curl_easy_cleanup(curl);return ret;}/*http post func */int curl_http_post(struct curl_http_args_st *args){//创建curl对象 CURL *curl; CURLcode return_code;struct curl_httppost *formpost = NULL;// POST 需要的参数struct curl_httppost *lastptr  = NULL;    int ret = -1;int post_type = 1; // POST 可以有三种方法// 如果要保存为文件, 先建立文件目录if (args->file_name)    create_dir(args->file_name);    //curl初始化 curl = curl_easy_init(); if (!curl){curl_printf("%s[%d]: curl easy init failed\n", __FUNCTION__, __LINE__);return ret;;}if (strncmp(args->url, "https://", 8) == 0){#if 1// 方法1, 设定为不验证证书和HOSTcurl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 0L);curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 0L);#else// 方法2, 设定一个SSL判别证书curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 1L);curl_easy_setopt(curl,CURLOPT_CAINFO,"ca-cert.pem"); // TODO: 设置一个证书文件#endif }curl_easy_setopt(curl,CURLOPT_HEADER,0);//设置httpheader 解析, 不需要将HTTP头写传入回调函数curl_easy_setopt(curl, CURLOPT_URL,args->url);//设置远端地址 curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L);// TODO: 打开调试信息curl_easy_setopt(curl,CURLOPT_FOLLOWLOCATION,1);//设置允许302  跳转curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, curl_write_data_cb); //执行写入文件流操作 的回调函数curl_easy_setopt(curl, CURLOPT_WRITEDATA, args);// 设置回调函数的第4 个参数        curl_easy_setopt(curl, CURLOPT_IPRESOLVE, CURL_IPRESOLVE_V4);//设备为ipv4类型curl_easy_setopt(curl, CURLOPT_CONNECTTIMEOUT, 30); //设置连接超时，单位s, CURLOPT_CONNECTTIMEOUT_MS 毫秒// curl_easy_setopt(curl,CURLOPT_TIMEOUT, 5);// 整个CURL 执行的时间, 单位秒, CURLOPT_TIMEOUT_MS毫秒curl_easy_setopt(curl, CURLOPT_NOSIGNAL, 1);//linux多线程情况应注意的设置(防止curl被alarm信号干扰)if (post_type == 1){// 方法1, 普通的POST , application/x-www-form-urlencodedcurl_easy_setopt(curl,CURLOPT_POST, 1);// 设置 为POST 方法curl_easy_setopt(curl,CURLOPT_POSTFIELDS, args->post_data);// POST 的数据内容curl_easy_setopt(curl,CURLOPT_POSTFIELDSIZE,strlen(args->post_data));// POST的数据长度, 可以不要此选项}else if (post_type == 2){//方法2, multipart/formdata请求, POST args->post_data 中的数据, 也可以是将文件内容读取到post_data中curl_formadd(&formpost, &lastptr, CURLFORM_PTRNAME, "reqformat", CURLFORM_PTRCONTENTS, "plain", CURLFORM_END);// 设置POST 参数curl_formadd(&formpost, &lastptr, CURLFORM_PTRNAME, "file", CURLFORM_PTRCONTENTS, args->post_data, CURLFORM_CONTENTSLENGTH, strlen(args->post_data), CURLFORM_END);curl_easy_setopt(curl, CURLOPT_HTTPPOST, formpost);}else if (post_type == 3){//添加内容Content-Disposition: form-data; name="reqformat"....plain curl_formadd(&formpost, &lastptr, CURLFORM_PTRNAME, "reqformat", CURLFORM_PTRCONTENTS, "plain", CURLFORM_END);// 设置POST 参数// 添加上传文件,  Content-Disposition: form-data; name="file"; filename="1.jpg"; filename为默认的名字, content-type 为默认curl识别的//curl_formadd(&formpost, &lastptr, CURLFORM_PTRNAME, "file", CURLFORM_FILE, args->post_file, CURLFORM_END);// 添加上传文件,  //Content-Disposition: form-data; name="file"; filename="1.jpg".,   filename为指定的名字, content-type 为默认curl识别的//curl_formadd(&formpost, &lastptr, CURLFORM_PTRNAME, "file", CURLFORM_FILE, err_file, CURLFORM_FILENAME, "1.jpg", CURLFORM_END); // 添加上传文件,  //Content-Disposition: form-data; name="file"; filename="1.jpg".,   filename为指定的名字, content-type为指定的类型//curl_formadd(&formpost, &lastptr, CURLFORM_PTRNAME, "file", CURLFORM_FILE, err_file, CURLFORM_FILENAME, "1.jpg", CURLFORM_CONTENTTYPE, "image/jpeg", CURLFORM_END);// 引用页:  http://blog.csdn.net/zxgfa/article/details/8302059curl_easy_setopt(curl, CURLOPT_HTTPPOST, formpost);}return_code = curl_easy_perform(curl); if (CURLE_OK != return_code){curl_printf("curl_easy_perform() failed: %s\n", curl_easy_strerror(return_code));ret  = 0;}if (args->file_fd)// 若需要再次处理写入的文件, 在此可以直接使用{ //关闭文件流fclose(args->file_fd); } if (args->data)// 若要对返回的内容进行处理, 可在此处理{curl_printf("data_len:%d\n%s\n", args->data_len, args->data);free(args->data);args->data = NULL;}curl_easy_cleanup(curl);if (post_type == 2 || post_type == 3)// 用这两种方法需要释放POST数据. curl_formfree(formpost);return ret;}/*1, 从参数中传入操作选项.2. 若在线程中要用到HTTPS , 请参看allexamples/threaded-ssl.c 文件使用*/int main(int argc, char **argv){//步骤一std::string app_id = "";//更改为你的公众号APP_IDstd::string app_secret = "";//更改为你的公众号APP_SECRETstd::string access_token = "";//访问Tokenstd::string access_token_geturl = "https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=" + app_id + "&secret=" + app_secret;//获取ACCESS_TOKEN，每天限制2000次，请珍惜！！！std::string openid = "";//粉丝用户OPENID列表，next_openid：获取关注用户列表偏移量，不填默认从头开始拉取std::string openid_geturl = "https://api.weixin.qq.com/cgi-bin/user/get?access_token=" + access_token + "&next_openid=";struct curl_http_args_st curl_args;memset(&curl_args, 0x00, sizeof(curl_args));/* Must initialize libcurl before any threads are started */curl_global_init(CURL_GLOBAL_ALL);/* 多线程使用SSL时, 需要先初始化锁*///init_locks();  #if 0 // GETcurl_args.curl_method = CURL_METHOD_GET;//strncpy(curl_args.url, "http://news.baidu.com/index.html", sizeof(curl_args.url)); // http  test ok //strncpy(curl_args.url, "https://www.baidu.com/index.html", sizeof(curl_args.url)); // https test okstrncpy(curl_args.url, access_token_geturl.c_str(), sizeof(curl_args.url)); // https test okstrncpy(curl_args.file_name, "index.html", sizeof(curl_args.file_name));#endif #if 1 // POSTcurl_args.curl_method = CURL_METHOD_POST;std::string mymessagestring = "hello world from PC by curl...";std::string message_sendurl = "https://api.weixin.qq.com/cgi-bin/message/custom/send?access_token=" + access_token;//客服消息发送接口std::string message_detail = "{\"touser\":\"" + openid +"\",\"msgtype\":\"text\",\"text\":{\"content\":\"" + mymessagestring + "\"}}";//发送具体消息strncpy(curl_args.url, message_sendurl.c_str(), sizeof(curl_args.url));//请求API地址strncpy(curl_args.post_data, message_detail.c_str(), sizeof(curl_args.post_data)); // 普通POST 1 OK// strncpy(curl_args.post_file, "./xx.mp4", sizeof(curl_args.post_file)); // POST 文件OK , 用方法3//strncpy(curl_args.post_file, "./post_file.txt", sizeof(curl_args.post_file)); // POST 文件OK//strncpy(curl_args.file_name, "index.html", sizeof(curl_args.file_name));#endif switch(curl_args.curl_method){case CURL_METHOD_GET:{curl_http_get(&curl_args);break;}case CURL_METHOD_POST:{curl_http_post(&curl_args);break;}default:{curl_printf("curl method error:%d\n", curl_args.curl_method);break;}}/*退出时, 释放锁*///kill_locks();return 0;}

完整工程：http://download.csdn.net/download/houwenbin1986/10139811