为什么要缓存token?
这里的token指的是微信JSAPI中基础支持的ACCESS_TOKEN,并非网页授权ACCESS_TOKEN。网页授权Token每天的调用次数没有限制,不需要缓存。
接口 | 每日限额 |
---|---|
获取access_token | 2000 |
自定义菜单创建 | 1000 |
自定义菜单查询 | 10000 |
获取用户基本信息 | 5000000 |
获取网页授权access_token | 无 |
刷新网页授权access_token | 无 |
网页授权获取用户信息 | 无 |
从上面的表格我们可以看到,微信基础支持的token每天调用频次为2000次。而token的有效时间为7200s,当实现了token的全局缓存后,理论每天只需要调用12次。相反,2000次即使仅供微信分享回调,在有一定用户基础的项目中完全满足不了。
缓存方案
- 项目启动时开启一个定时器,每7180s执行一次Http请求,从微信获取最新的access_token并将redis中旧的access_token替换掉。
- 代码中有需要使用access_token时,直接从缓存中读取。
Spring Boot使用定时器
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.sql.SQLException;
import javax.annotation.Resource;
import org.apache.log4j.Logger;
import org.springframework.scheduling.annotation.Scheduled;
import org.springframework.stereotype.Component;
import com.bjb.dao.impl.RedisTokenHelper;
import net.sf.json.JSONObject;
/**
* 全局定时器
* @author qiqj
*
*/
@Component
public class Scheduler {
private final Logger logger = Logger.getRootLogger();
@Resource
private RedisTokenHelper redisTokenHelper;
/**
* 定时获取access_token
* @throws SQLException
*/
@Scheduled(fixedDelay=7180000)
public void getAccessToken() throws SQLException{
logger.info("==============开始获取access_token===============");
String access_token = null;
String grant_type = "client_credential";
String AppId= WxPropertiseUtil.getProperty("appid");
String secret= WxPropertiseUtil.getProperty("secret");
String url = "https://api.weixin.qq.com/cgi-bin/token?grant_type="+grant_type+"&appid="+AppId+"&secret="+secret;
try {
URL urlGet = new URL(url);
HttpURLConnection http = (HttpURLConnection) urlGet.openConnection();
http.setRequestMethod("GET"); // 必须是get方式请求
http.setRequestProperty("Content-Type","application/x-www-form-urlencoded");
http.setDoOutput(true);
http.setDoInput(true);
http.connect();
InputStream is = http.getInputStream();
int size = is.available();
byte[] jsonBytes = new byte[size];
is.read(jsonBytes);
String message = new String(jsonBytes, "UTF-8");
JSONObject demoJson = JSONObject.fromObject(message);
//System.out.println("JSON字符串:"+demoJson);
access_token = demoJson.getString("access_token");
is.close();
logger.info("==============结束获取access_token===============");
} catch (Exception e) {
e.printStackTrace();
}
logger.info("==============开始写入access_token===============");
redisTokenHelper.saveObject("global_token", access_token);
logger.info("==============写入access_token成功===============");
}
}
读取配置文件工具类
import java.io.IOException;
import java.io.InputStream;
import java.util.Properties;
import org.apache.log4j.Logger;
/** * 读取微信配置文件 wxconfig.properties工具类 * @author qiqj * */ public class WxPropertiseUtil { private static Properties properties = new Properties(); protected static final Logger logger = Logger.getRootLogger(); static{ InputStream in = WxPropertiseUtil.class.getClassLoader().getResourceAsStream("wxconfig.properties"); try { properties.load(in); } catch (IOException e) { e.printStackTrace(); logger.error(e.getMessage()); } } public static String getProperty(String key){ return properties.getProperty(key); } public static void UpdateProperty(String key,String value){ properties.setProperty(key, value); } }
微信配置文件
appid=xxxx
secret=xxxxxx
Redis操作工具类
import java.util.concurrent.TimeUnit;
import javax.annotation.Resource;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.core.StringRedisTemplate; import org.springframework.data.redis.core.ValueOperations; import org.springframework.stereotype.Repository; /** * 封装Redis存取Token对的工具类 * @author qiqj * */ @Repository public class RedisTokenHelper { @Autowired StringRedisTemplate stringRedisTemplate; @Autowired RedisTemplate<Object, Object> redisTemplate; @Resource(name="stringRedisTemplate") ValueOperations<String, String> ops; @Resource(name="redisTemplate") ValueOperations<Object, Object> objOps; /** * 键值对存储 字符串 :有效时间3分钟 * @param tokenType Token的key * @param Token Token的值 */ public void save(String tokenType,String Token){ ops.set(tokenType, Token, 180, TimeUnit.SECONDS); } /** * 根据key从redis获取value * @param tokenType * @return String */ public String getToken(String tokenType){ return ops.get(tokenType); } /** * redis 存储一个对象 * @param key * @param obj * @param timeout 过期时间 单位:s */ public void saveObject(String key,Object obj,long timeout){ objOps.set(key, obj,timeout,TimeUnit.SECONDS); } /** * redis 存储一个对象 ,不过期 * @param key * @param obj */ public void saveObject(String key,Object obj){ objOps.set(key, obj); } /** * 从redis取出一个对象 * @param key * @param obj */ public Object getObject(String key){ return objOps.get(key); } /** * 根据Key删除Object * @param key */ public void removeObject(String key){ redisTemplate.delete(key); } }
简单测试
import org.apache.log4j.Logger;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.boot.test.SpringApplicationConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner; import org.springframework.test.context.web.WebAppConfiguration; import org.springframework.transaction.annotation.Transactional; import com.bjb.Application; import com.bjb.dao.impl.RedisTokenHelper; /** * Junit单元测试类 * @author qiqj * */ @RunWith(SpringJUnit4ClassRunner.class) @SpringApplicationConfiguration(classes=Application.class) @WebAppConfiguration @Transactional public class JUnitTest { private final Logger logger = Logger.getRootLogger(); @Resource private RedisTokenHelper redisTokenHelper; @Test public void test(){ String access_token = (String) redisTokenHelper.getObject("global_token"); System.out.println("access_token:"+access_token); } }