pending-promise-recycler-express - part 1

pending-promise-recycler-express.js

'use strict';

const express = require('express');
const recycle = require('pending-promise-recycler');

const server = express();

const someSlowAndExpensiveOperation = function () {
    return new Promise((resolve, reject) => {
        console.log('Starting a very slow operation!')
        setTimeout(() => {
            console.log('Slow operation is over!')
            resolve({ foo: 'bar' });
        }, 1500);
    });
}

server.get('/', async function (req, res) {
    console.log('>>> Incoming request');
    const recycledOperation = recycle(someSlowAndExpensiveOperation, {
        keyBuilder: 'slow-and-expensive' // Optionally define your own mechanism to uniquely identify functions
    });
    const data = await recycledOperation();
    res.json(data);
    console.log('<<< Outgoing response');
})

server.listen(3000, () => {
    console.log('Express server up and running!');
});