前言
越来越多的企业借助微信平台做开发，下面记录最近开发微信项目（企业号）一些关键设置、原理及代码
一：添加应用
关注企业微信号后，点击企业号，能看到该企业号下的应用列表，它类似我们常见后台中的模块或栏目，首先我们要创建自己的应用。
二：设置应用为回调模式
创建好应用后，把应用设置成回调模式，按要求设置回调URL及密钥。保存时它会访问URL，只有URL能正确访问信息时才能保存成功，否则一直会提示失败
原理
以下摘自微信开发文档：
验证URL有效性
当你提交以上信息时，企业号将发送GET请求到填写的URL上，GET请求携带四个参数，企业在获取时需要做urldecode处理，否则会验证不成功。
参数 | 描述 | 是否必带 |
msg_signature | 微信加密签名，msg_signature结合了企业填写的token、请求中的timestamp、nonce参数、加密的消息体 | 是 |
timestamp | 时间戳 | 是 |
nonce | 随机数 | 是 |
echostr | 加密的随机字符串，以msg_encrypt格式提供。需要解密并返回echostr明文，解密后有random、msg_len、msg、$CorpID四个字段，其中msg即为echostr明文 | 首次校验时必带 |
企业通过参数msg_signature对请求进行校验，如果确认此次GET请求来自企业号，那么企业应用对echostr参数解密并原样返回echostr明文(不能加引号，不能带bom头，不能带换行符)，则接入验证生效，回调模式才能开启。
实操
为了能正确验证URL有效性，还需要以下操作
首先，我们需要一台服务器，并且有一个域名指向了该服务器，在该服务器上配置好网站。把验证URL的代码放置在该服务器上。wxpush代码如下：
package com.bf.weixin;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.bf.meal.entity.App;
import com.qq.weixin.mp.aes.AesException;
import com.qq.weixin.mp.aes.WXBizMsgCrypt;
public class wxpush extends HttpServlet {
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
WXBizMsgCrypt wxcpt = null;
try {
wxcpt = new WXBizMsgCrypt(App.getToken(), App.getEncodingAESKey(), App.getCorpID());
} catch (AesException e1) {
e1.printStackTrace();
}
// 解析出url上的参数值如下：
String sVerifyMsgSig = request.getParameter("msg_signature");
String sVerifyTimeStamp = request.getParameter("timestamp");
String sVerifyNonce = request.getParameter("nonce");
String sVerifyEchoStr = request.getParameter("echostr");
App.logger.info("url:" + request.getQueryString());
String sEchoStr; //需要返回的明文
try {
sEchoStr = wxcpt.VerifyURL(sVerifyMsgSig, sVerifyTimeStamp, sVerifyNonce, sVerifyEchoStr);
App.logger.info("verifyurl echostr: " + sEchoStr);
response.setContentType("text/html");
PrintWriter out = response.getWriter();
out.println(sEchoStr);
out.flush();
out.close();
} catch (Exception e) {
App.logger.error(e);
e.printStackTrace();
}
}
}
注：需要到微信官网上下载
com.qq.weixin.mp.aes.AesException;
com.qq.weixin.mp.aes.WXBizMsgCrypt;
当然web.xml中还得有如下节点
<servlet-mapping>
<servlet-name>wxpush</servlet-name>
<url-pattern>/servlet/wxpush</url-pattern>
</servlet-mapping>
配置好后，应该能正确的访问URL(http://*.*.com.cn/meal/servlet/wxpush)，把该URL作为微信后台填写的值，此时应该能正确保存了。
三：获取用户帐号信息
要针对企业号关注用户做一些应用，最重要一点是要识别该用户，以便能正确区分不同的用户。
根据文档OAuth2.0验证接口说明, 建议的方案
1、企业应用中的URL链接直接填写企业自己的页面地址
2、成员跳转到企业页面时，企业校验是否有代表成员身份的cookie，此cookie由企业生成
3、如果没有获取到cookie，重定向到OAuth验证链接，获取成员身份后，由企业生成代表成员身份的cookie
4、根据cookie获取成员身份，进入相应的页面
我的做法是，配置Filter拦截所有jsp或.do文件的请求，在Filter中先去Cookie,如果Cookie不存在，则调用OAuth2.0获取信息，具体还是看关键代码
public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws ServletException, IOException {
HttpServletRequest request = (HttpServletRequest) req;
HttpServletResponse response = (HttpServletResponse) res;
String userId = getUserId(request, response);
……
private String getUserId( HttpServletRequest request, HttpServletResponse response) throws IOException{
Cookie cookieUser = CookieHelper.getCookieByName(request, App.COOKIE_USER);
String userId = "";
if (cookieUser != null)
{
userId = cookieUser.getValue();
}
else
{
String code = request.getParameter("code"); //企业code
if (code == null) //为空时，需 构造OAuth链接，OAuth返回时会带上code
{
String url = request.getRequestURL().toString();
url = OAuthHelper.OAuth(java.net.URLEncoder.encode(url, "UTF-8"));
response.sendRedirect(url);
return "";
}
try {
userId = OAuthHelper.getUserByCode(code);
} catch (Exception e) {
}
if (userId == null)
{
return "";
}
CookieHelper.addCookie(response, App.COOKIE_USER, userId, App.Cookie_Age);
}
return userId;
}
下面为封装的工具类，与项目无关
public class OAuthHelper {
static Logger logger = Logger.getLogger(OAuthHelper.class.getName());
private static String Token_URL = "https://qyapi.weixin.qq.com/cgi-bin/gettoken?corpid=%s&corpsecret=%s";
private static String OAuth_URL = "https://open.weixin.qq.com/connect/oauth2/authorize?appid=%s&redirect_uri=%s&response_type=code&scope=snsapi_base&state=ATTENDANCE#wechat_redirect";
private static String GetUserInfoUrl = "https://qyapi.weixin.qq.com/cgi-bin/user/getuserinfo?access_token=%s&code=%s";
public static String getUserByCode(String code) throws Exception{
String userId = null;
String token = getToken();
String url = String.format(GetUserInfoUrl, token, code);
OAuth oauthInfo = HttpHelper.GetOAuthInfo(url);
if (oauthInfo != null)
{
userId = oauthInfo.getUserId();
}
return userId;
}
public static String OAuth(String url){
String fullUrl = String.format(OAuth_URL, App.getCorpID(), url);
return fullUrl;
}
private static String getToken() throws Exception{
String url = String.format(Token_URL, App.getCorpID(), App.getCorpSecret());
return HttpHelper.GetTokenInfo(url).getAccessToken();
}
}
下面最好是用泛型消除重复代码
import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
public class HttpHelper {
public static OAuth GetOAuthInfo(String url) throws IOException{
CloseableHttpClient httpclient = HttpClients.createDefault();
HttpGet httpget = new HttpGet(url);
ResponseHandler<OAuth> rh = new ResponseHandler<OAuth>() {
@Override
public OAuth handleResponse(final HttpResponse response) throws IOException {
StatusLine statusLine = response.getStatusLine();
HttpEntity entity = response.getEntity();
if (statusLine.getStatusCode() >= 300) {
throw new HttpResponseException(
statusLine.getStatusCode(),
statusLine.getReasonPhrase());
}
if (entity == null) {
throw new ClientProtocolException("Response contains no content");
}
Gson gson = new GsonBuilder().create();
ContentType contentType = ContentType.getOrDefault(entity);
Reader reader = new InputStreamReader(entity.getContent(), contentType.getCharset());
return gson.fromJson(reader, OAuth.class);
}
};
OAuth myjson = httpclient.execute(httpget, rh);
return myjson;
}
public static WeChartToken GetTokenInfo(String url) throws Exception{
SslHelper.ignoreSsl();
CloseableHttpClient httpclient = HttpClients.createDefault();
HttpGet httpget = new HttpGet(url);
ResponseHandler<WeChartToken> rh = new ResponseHandler<WeChartToken>() {
@Override
public WeChartToken handleResponse(final HttpResponse response) throws IOException {
StatusLine statusLine = response.getStatusLine();
HttpEntity entity = response.getEntity();
if (statusLine.getStatusCode() >= 300) {
throw new HttpResponseException(
statusLine.getStatusCode(),
statusLine.getReasonPhrase());
}
if (entity == null) {
throw new ClientProtocolException("Response contains no content");
}
Gson gson = new GsonBuilder().create();
ContentType contentType = ContentType.getOrDefault(entity);
Reader reader = new InputStreamReader(entity.getContent(), contentType.getCharset());
return gson.fromJson(reader, WeChartToken.class);
}
};
WeChartToken myjson = httpclient.execute(httpget, rh);
return myjson;
}
}
import java.security.cert.CertificateException;
import java.security.cert.X509Certificate;
import javax.net.ssl.HostnameVerifier;
import javax.net.ssl.HttpsURLConnection;
import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLSession;
import javax.net.ssl.TrustManager;
import javax.net.ssl.X509TrustManager;
public class SslHelper {
private static void trustAllHttpsCertificates() throws Exception {
TrustManager[] trustAllCerts = new TrustManager[1];
TrustManager tm = new miTM();
trustAllCerts[0] = tm;
SSLContext sc = SSLContext.getInstance("SSL");
sc.init(null, trustAllCerts, null);
HttpsURLConnection.setDefaultSSLSocketFactory(sc.getSocketFactory());
}
static class miTM implements TrustManager,X509TrustManager {
public X509Certificate[] getAcceptedIssuers() {
return null;
}
public boolean isServerTrusted(X509Certificate[] certs) {
return true;
}
public boolean isClientTrusted(X509Certificate[] certs) {
return true;
}
public void checkServerTrusted(X509Certificate[] certs, String authType)
throws CertificateException {
return;
}
public void checkClientTrusted(X509Certificate[] certs, String authType)
throws CertificateException {
return;
}
}
/**
* 忽略HTTPS请求的SSL证书，必须在openConnection之前调用
* @throws Exception
*/
public static void ignoreSsl() throws Exception{
HostnameVerifier hv = new HostnameVerifier() {
public boolean verify(String urlHostName, SSLSession session) {
System.out.println("Warning: URL Host: " + urlHostName + " vs. " + session.getPeerHost());
return true;
}
};
trustAllHttpsCertificates();
HttpsURLConnection.setDefaultHostnameVerifier(hv);
}
}
public class App {
private static Properties config;
private App()
{}
private static Properties getInstance(){
if( config == null )
{
config = new Properties();
try {
config.load(App.class.getClassLoader().getResourceAsStream("/config.properties"));
} catch (IOException e) {
e.printStackTrace();
}
}
return config;
}
public static String getToken() {
return getInstance().getProperty("Token");
}
public static String getCorpID() {
return getInstance().getProperty("CORP_ID");
}
public static String getCorpSecret() {
return getInstance().getProperty("CORP_SECRET");
}
public static String getEncodingAESKey() {
return getInstance().getProperty("EncodingAESKey");
}
public static String getSERVICE_URL() {
return getInstance().getProperty("SERVICE_URL");
}
}
最后是src/config.properties配置文件：
Token = ***
CORP_ID = ***
CORP_SECRET = ***
EncodingAESKey = ***
以及实体类
public class OAuth {
private String UserId;
public String getUserId() {
return UserId;
}
public void setUserId(String userId) {
UserId = userId;
}
}
public class WeChartToken {
private String access_token;
public String getAccessToken() {
return access_token;
}
public void setAccessToken(String access_token) {
this.access_token = access_token;
}
}
补充
问题一：今天在做新的微信项目时，以上代码一直提示解密失败
尝试获取参数方式为：
String sVerifyMsgSig = URLDecoder.decode(request.getParameter("msg_signature"),"utf-8");
String sVerifyTimeStamp = URLDecoder.decode(request.getParameter("timestamp"),"utf-8");
String sVerifyNonce = URLDecoder.decode(request.getParameter("nonce"),"utf-8");
String sVerifyEchoStr = URLDecoder.decode(request.getParameter("echostr"),"utf-8");
本地显示解密成功后，上传到服务器提示解密失败。
根据 ，去Oracle官网下载jce_policy-8.zip，把解压后得到的两个jar包，
覆盖C:\Program Files\Java\jre1.8.0_65\lib\security目录下原有文件即可。
问题二：redirect_uri参数错误
加解密问题解决后，通过微信打开链接一直报"redirect_uri参数错误"。
原因：没有设置好可信域名。
注意：有两个地方可以设置可信域名，一个是在应用中心->自建应用，模式选择上面，还有一处是在设置->功能设置处，之所以出错是我在第二处设置了而非第一处。
最后放出基于Spring MVC的web.xml
<web-app xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
version="2.5">
<display-name>wim</display-name>
<description>wim</description>
<filter>
<filter-name>WeChartFilter</filter-name>
<filter-class>com.XX.weixin.WeChartFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>WeChartFilter</filter-name>
<url-pattern>*</url-pattern> /*这里设置filter是要让每个页面访问之前，先去取微信用户ID*/
</filter-mapping>
<!-- For web context -->
<servlet>
<servlet-name>spring-dispatcher</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/spring-mvc-config.xml</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>spring-dispatcher</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
<servlet>
<servlet-name>WeChatCallback</servlet-name>
<servlet-class>com.XX.weixin.WeChatCallback</servlet-class> /*回调地址设置*/
</servlet>
<servlet-mapping>
<servlet-name>WeChatCallback</servlet-name>
<url-pattern>/callback</url-pattern>
</servlet-mapping>
<!-- For root context -->
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
<listener>
<listener-class>org.springframework.web.context.request.RequestContextListener</listener-class>
</listener>
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/spring-core-config.xml</param-value>
</context-param>
</web-app>
本文章为转载内容，我们尊重原作者对文章享有的著作权。如有内容错误或侵权问题，欢迎原作者联系我们进行内容更正或删除文章。
