httpClient实现微信公众号消息群发

1、实现功能　

　　向关注了微信公众号的微信用户群发消息。（可以是所有的用户，也可以是提供了微信openid的微信用户集合）

2、基本步骤

前提：

　　已经有认证的公众号或者测试公众账号

发送消息步骤：

1. 发送一个请求微信去获取access_token
2. 发送一个请求去请求微信发送消息

相关微信接口的信息可以查看：http://www.cnblogs.com/0201zcr/p/5866296.html 有测试账号的申请 + 获取access_token和发送微信消息的url和相关的参数需求。各个参数的意义等。

3、实践

　　这里通过HttpClient发送请求去微信相关的接口。

1）maven依赖

<dependency>
    <groupId>org.apache.httpcomponents</groupId>
    <artifactId>httpclient</artifactId>
    <version>4.3.1</version>
</dependency>

2）httpClient使用方法

使用HttpClient发送请求、接收响应很简单，一般需要如下几步即可。

1. 创建HttpClient对象。
2. 创建请求方法的实例，并指定请求URL。如果需要发送GET请求，创建HttpGet对象；如果需要发送POST请求，创建HttpPost对象。
3. 如果需要发送请求参数，可调用HttpGet、HttpPost共同的setParams(HetpParams params)方法来添加请求参数；对于HttpPost对象而言，也可调用setEntity(HttpEntity entity)方法来设置请求参数。
4. 调用HttpClient对象的execute(HttpUriRequest request)发送请求，该方法返回一个HttpResponse。
5. 调用HttpResponse的getAllHeaders()、getHeaders(String name)等方法可获取服务器的响应头；调用HttpResponse的getEntity()方法可获取HttpEntity对象，该对象包装了服务器的响应内容。程序可通过该对象获取服务器的响应内容。
6. 释放连接。无论执行方法是否成功，都必须释放连接——这里使用了连接池，可以交给连接池去处理

3）实例

1、发送请求的类

import com.alibaba.druid.support.json.JSONUtils;
import com.alibaba.druid.support.logging.Log;
import com.alibaba.druid.support.logging.LogFactory;
import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
import com.seewo.core.util.json.JsonUtils;
import org.apache.commons.collections.map.HashedMap;
import org.apache.commons.lang.StringUtils;
import org.apache.http.HttpHost;
import org.apache.http.NameValuePair;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.ResponseHandler;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.conn.params.ConnRoutePNames;
import org.apache.http.conn.scheme.Scheme;
import org.apache.http.conn.ssl.SSLSocketFactory;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.BasicResponseHandler;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.impl.conn.PoolingClientConnectionManager;
import org.apache.http.message.BasicNameValuePair;
import org.springframework.http.HttpHeaders;
import org.springframework.http.MediaType;

import javax.net.ssl.SSLContext;
import javax.net.ssl.X509TrustManager;
import javax.security.cert.CertificateException;
import javax.security.cert.X509Certificate;
import java.io.IOException;
import java.text.MessageFormat;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;

/**
 * Created by zhengcanrui on 16/9/20.
 */
public class WechatAPIHander {

        /**
         * 获取token接口
         */
        private String getTokenUrl = "https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid={0}&secret={1}";
        /**
         * 拉微信用户信息接口
         */
        private String getUserInfoUrl = "https://api.weixin.qq.com/cgi-bin/user/info?access_token={0}&openid={1}";
        /**
         * 主动推送信息接口(群发)
         */
        private String sendMsgUrl = "https://api.weixin.qq.com/cgi-bin/message/mass/sendall?access_token={0}";

        private HttpClient webClient;
        private Log log = LogFactory.getLog(getClass());
        public void initWebClient(String proxyHost, int proxyPort){
            this.initWebClient();
            if(webClient != null && !StringUtils.isEmpty(proxyHost)){
                HttpHost proxy = new HttpHost(proxyHost, proxyPort);
                webClient.getParams().setParameter(ConnRoutePNames.DEFAULT_PROXY, proxy);
            }
        }
        /**
         * @desc 初始化创建 WebClient
         */
        public void initWebClient() {
            log.info("initWebClient start....");
            try {
                PoolingClientConnectionManager tcm = new PoolingClientConnectionManager();
                tcm.setMaxTotal(10);
                SSLContext ctx = SSLContext.getInstance("TLS");
                X509TrustManager tm = new X509TrustManager() {

                    @Override
                    public void checkClientTrusted(java.security.cert.X509Certificate[] x509Certificates, String s) throws java.security.cert.CertificateException {

                    }

                    @Override
                    public void checkServerTrusted(java.security.cert.X509Certificate[] x509Certificates, String s) throws java.security.cert.CertificateException {

                    }

                    @Override
                    public java.security.cert.X509Certificate[] getAcceptedIssuers() {
                        return new java.security.cert.X509Certificate[0];
                    }
                };
                ctx.init(null, new X509TrustManager[] { tm }, null);
                SSLSocketFactory ssf = new SSLSocketFactory(ctx, SSLSocketFactory.ALLOW_ALL_HOSTNAME_VERIFIER);
                Scheme sch = new Scheme("https", 443, ssf);
                tcm.getSchemeRegistry().register(sch);
                webClient = new DefaultHttpClient(tcm);
            } catch (Exception ex) {
                log.error("initWebClient exception", ex);
            } finally {
                log.info("initWebClient end....");
            }
        }
        /**
         * @desc 获取授权token
         * @param appid
         * @param secret
         * @return
         */
        public String getAccessToken(String appid, String secret) {
            String accessToken = null;
            try {
                log.info("getAccessToken start.{appid=" + appid + ",secret:" + secret + "}");
                String url = MessageFormat.format(this.getTokenUrl, appid, secret);
                String response = executeHttpGet(url);
                Map map = JsonUtils.jsonToMap(response);
                accessToken = (String) map.get("access_token");
               /* Object Object = JSONUtils.parse(response);

                accessToken = jsonObject.getString("access_token");*/
//                accessToken = JsonUtils.read(response, "access_token");
            } catch (Exception e) {
                log.error("get access toekn exception", e);
            }
            return accessToken;
        }
        /**
         * @desc 推送信息
         * @param token
         * @param msg
         * @return
         */
        public String sendMessage(String token,String msg){
            try{
                log.info("\n\nsendMessage start.token:"+token+",msg:"+msg);
                String url = MessageFormat.format(this.sendMsgUrl, token);
                HttpPost post = new HttpPost(url);
                ResponseHandler<?> responseHandler = new BasicResponseHandler();

                //这里必须是一个合法的json格式数据,每个字段的意义可以查看上面连接的说明,content后面的test是要发送给用户的数据,这里是群发给所有人
                msg = "{\"filter\":{\"is_to_all\":true},\"text\":{\"content\":\"test\"},\"msgtype\":\"text\"}\"";

                //设置发送消息的参数
                StringEntity entity = new StringEntity(msg);

                //解决中文乱码的问题
                entity.setContentEncoding("UTF-8");
                entity.setContentType("application/json");
                post.setEntity(entity);

                //发送请求
                String response = (String) this.webClient.execute(post, responseHandler);
                log.info("return response=====start======");
                log.info(response);
                log.info("return response=====end======");
                return response;

            }catch (Exception e) {
                log.error("get user info exception", e);
                return null;
            }
        }

        /**
         * @desc 发起HTTP GET请求返回数据
         * @param url
         * @return
         * @throws IOException
         * @throws ClientProtocolException
         */
        private String executeHttpGet(String url) throws IOException, ClientProtocolException {
            ResponseHandler<?> responseHandler = new BasicResponseHandler();
            String response = (String) this.webClient.execute(new HttpGet(url), responseHandler);
            log.info("return response=====start======");
            log.info(response);
            log.info("return response=====end======");
            return response;
        }

}

2、Controller和Service层调用

  @RequestMapping(value = "/testHttpClient", method = RequestMethod.GET)
    public DataMap test() {
        WechatAPIHander wechatAPIHander = new WechatAPIHander();

        //获取access_token
　　　　　　//第一个参数是你appid，第二个参数是你的秘钥，需要根据你的具体情况换
        String accessToken = wechatAPIHander.getAccessToken("appid","scerpt");  

       //发送消息
        wechatAPIHander.sendMessage(accessToken, "测试数据");

        return new DataMap().addAttribute("DATA",accessToken);
    }
    

3、结果

　　假如你关注了微信公众号中看到你刚刚发送的test消息。

HttpClient学习文档：https://pan.baidu.com/s/1miO1eOg

致谢：感谢您的阅读