Use msgsecheck interface to detect text

https://developers.weixin.qq.com/miniprogram/dev/api-backend/open-api/sec-check/security.msgSecCheck.html
The request interface address is https://api.weixin.qq.com/wxa/msg'sec'check? Access'token = access'token
, for POST request, the request parameters are:

• Access? Token interface call credentials
• Content the text content to be detected, with a length of no more than 500KB

let content = params.content;
let access_token = await this.app.redis.get('access_token');
      let url = `https://api.weixin.qq.com/wxa/msg_sec_check?access_token=${access_token}`;
      let data = {
        content: content
      }
      let checkResult = await proxy(url, {
        headers: {
          'Content-Type': 'application/json'
        },
        method: 'POST',
        body: JSON.stringify(data)
      });
      checkResult = JSON.parse(checkResult);
if (checkResult.errcode == 87014) {
        // Content contains illegal content
        response = this.ResultResponse.createByErrorMsg('Content contains illegal content');
      }

Refresh the access token certificate regularly

access_token is the interface call certificate, which is obtained through the getAccessToken interface.
https://developers.weixin.qq.com/miniprogram/dev/api-backend/open-api/access-token/auth.getAccessToken.html

The interface request address is https://api.weixin.qq.com/cgi-bin/token? Grant'type = client'credential & appid = apppid & Secret = appsecret, which is GET request. The request parameters are:

• Grant type fill in client credential
• AppID applet unique certificate, that is, AppID
• secret the unique credential key of the applet, that is, AppSecret

The interface returns data in addition to access_token and expires_in expiration time. Here, the validity period is 7200s, which means that the certificate fails in two hours. Therefore, we need to refresh the timer to obtain access_token, and then store it in redis.

/////////Get access token.js file
const Subscription = require('egg').Subscription;
/**
 * Get wechat accessToken timing task once every 90 (5400 s) minutes
 */
class GetAceessToken extends Subscription {
  // Use the schedule property to set the execution interval and other configurations of scheduled tasks
  static get schedule() {
    return {
      interval: '5400s', // 1 minute interval in m minutes, s seconds, ms milliseconds 
      type: 'all', // All specifies that all workers need to execute the worker. Only one worker on each machine will execute this scheduled task.
      immediate: true, //When the parameter is configured as true, the timing task will execute once after the application is started and ready.
      disable: false//When this parameter is configured as true, this scheduled task will not be started.
    };
  }

  // subscribe is a function that is run when a real scheduled task is executed
  async subscribe() {
    let ctx = this.ctx;
    ctx.logger.info('-----getAccessToken start----');
    try {
      await ctx.service.userService.getAccessToken();
    } catch (error) {
      console.log('Obtain access token fail', error)
    }
    ctx.logger.info('-----getAccessToken end----');
  }
}

module.exports = GetAceessToken;

/////////userService.js file
/**
  * Obtain the AccessToken and store it in redis for security content check to refresh every 90 minutes
  */
  async getAccessToken() {
    let url = `https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=${config.key.appid}&secret=${config.key.secret}`;
    let result = await proxy(url, {
      method: 'GET'
    });
    result = JSON.parse(result);
    console.log('getAccessToken result', result)
    await this.app.redis.set('access_token', result.access_token);
    await this.app.redis.set('expires_in', result.expires_in);//Currently valid for 7200s 2 hours
  }