Manage node state with redis.

redisNode.js

var redis = require('redis');
var client = redis.createClient(); //redis.createClient(port, host, options)

const key = 'test'; //redis key name

//Error handling
client.on("error", (err) => {
  console.log(`Error: ${err}`);
});


// set inital state to an empty object {}
client.set(key, JSON.stringify({}));


//replicate state updates using setInterval
setInterval(() => {
  
    //mock state update. 
    const newObject = {
        [Math.floor(Math.random() * 10) + 100)] : Math.floor(Math.random() * 5000) + 1,
        [Math.floor(Math.random() * 10) + 100)] : Math.floor(Math.random() * 5000) + 1,
        [Math.floor(Math.random() * 10) + 100)] : Math.floor(Math.random() * 5000) + 1,
    }
    
    // get key from redis
    client.get(key, (err, data) => {
        
        //convert string to native object
        let prevState = JSON.parse(data);
      
        //use spread operator to concat two objects
        let newState = {
            ...prevState,
            ...newObject,
        };
        
        //set key to newState
        client.set(key, JSON.stringify(newState));
        console.log(state)
      });
}, 500)



// quit client on CTRL + C
process.on('SIGINT', () => {
    client.quit();
    console.log('smooth exit redis')
    process.exit(0);
});