Egg (19): use egg redis performance optimization to cache data and improve response efficiency

Preface ：

        When writing interfaces with a large amount of data , I found that the response speed was too slow , Interface , Usually once 8s-12s, Such a long response time , It brings great inconvenience to users , Here is the cache method , To optimize the interface , After the first response , Cache the data , Then use the cached data to do some data operations .

Operation steps ：

1、 Computer installation redis Tools

window:

github Share ： entrance

Personal online disk sharing （ recommend ）

link ：https://pan.baidu.com/s/1c4mBdwhxJshvC3i_fI2_gg 

Extraction code ：

5ntg

linux install

 Check if the system is installed redis
yum info redis
 
 If not installed , Follow these steps 
 install epel library 
yum install epel-release -y
 install redis
yum install redis -y
 
 operation 
 start-up ：systemctl start redis
 restart ：systemctl restart redis
 close ：systemctl stop redis
 
 Set boot up 
systemctl enable redis

mac install

brew install redis
 
brew services start redis
 
redis-server /usr/local/etc/redis.conf

2、 The computer runs the newly installed redis Tools

（1） Put the newly downloaded installation package into your folder , Open this file zip , Then decompress

 （2） The extracted file , find redis-server.exe  This is the shortcut key to start the service , Click on

 （3） The following screen appears , On behalf of the service started , The port number is 6379

 （4）cmd Dynamically add , View cache contents

myKey Is your key value ,abc It is concrete. value value 


 Set key value pairs  set myKey abc
 Check the key value pairs  get myKey

1） Be careful , Just the second time 3 The service opened in step cannot be closed , Open one again cmd bounced

2） Input      redis-cli.exe -h 127.0.0.1 -p 6379 , If there are other errors , Don't worry ,

 3） Change command input      .\redis-cli.exe -h 127.0.0.1 -p 6379   , See the following service , It means success

 4） Enter our setup command , And then go back

 set demo 123456 

5） Get the cache content we just set , Be careful , We didn't set fruit abc, So what I got was （nil）, We set it up demo, You can see the specific content

get abc

3、egg Operations in the project

（1） Project installation plug-ins

npm i egg-redis -S

2、config/plugin.js Introduce plug-in in

exports.redis = {
    enable: true,
    package: 'egg-redis'
}

3、config.default.js Configure the connection address in

config.redis = {
  client: {
    port: 6379,
    host: '127.0.0.1',
    password: 'auth', 
    db: 0
  }, 
}

4、service Next Create a new service file redis.js

const Service = require('egg').Service;
const time = 60 * 60 * 24 * 365 // Default cache expiration time  365 God 
class RedisService extends Service {
  //  Set up 
  async set(key, value, seconds) {
    // seconds  Effective time 
    let { redis } = this.app;
    value = JSON.stringify(value);
    if(!seconds){
      // await redis.set(key, value);
      await redis.set(key, value, 'EX', time);
    }else{
      //  Set the effective time 
      await redis.set(key, value, 'EX', seconds);
    }
  }
  //  obtain 
  async get(key) {
    let { redis } = this.app;
    let data = await redis.get(key);
    if (!data) return;
    data = JSON.parse(data);
    return data;
  }
  //  Empty redis
  async flushall() {
    let { redis } = this.app;
    redis.flushall();
    return;
  }
}
module.exports = RedisService;

 5、 Method

（1） obtain

let xiaoshuo = await this.app.redis.get('xiaoshuo1');

（2） Set up

let str = 123
await this.app.redis.set('xiaoshuo1', str);

6、 Specific business use

async getXiaoshuo1() {
    let xiaoshuo = await this.app.redis.get('xiaoshuo1');
    // If there's cached data , Just use the cache directly 
    if(xiaoshuo){
        this.ctx.body = {
              code:200,
              masg:'success',
              data: {
                list:xiaoshuo 
              }
            }
        return
    }
    // obtain mysql data 
    let allList = await this.app.mysql.query(initSql);
    this.ctx.body = {
      code:200,
      masg:'success',
      data: {
        list:allList
      }
    };

}

7、 If you want to test the time of the request interface and the time after using the cache , The test method

console.time() //  Start timing 

let goodsList = await this.service.redis.get('goodsList');
if (!goodsList) {
  console.log(' No, redis cache ')
  goodsList = await this.app.mysql.select('goods');
  this.service.redis.set('goodsList', goodsList);

}

console.timeEnd() //  Print duration 
await this.ctx.body = goodsList;