app.js

/**
 * name : app.js
 * author : Aman Kumar Gupta
 * Date : 29-Sep-2021
 * Description : Start file of a user service
 */

const express = require('express');
const bodyParser = require('body-parser');
const cors = require('cors');
const expressFileUpload = require('express-fileupload');

require('dotenv').config({ path: './.env' });

let environmentData = require("./envVariables")();

if (!environmentData.success) {
    console.log("Server could not start . Not all environment variable is provided");
    process.exit();
}

require('./configs');

const app = express();

// Health check
require("./health-checks")(app);

app.use(cors());

app.use(expressFileUpload());

app.use(bodyParser.urlencoded({ extended: true, limit: '50MB' }));
app.use(bodyParser.json({ limit: '50MB' }));

app.use(express.static("public"));

/* Logs request info if environment is configured to enable log */
if (process.env.ENABLE_LOG === 'true') {
    app.all("*", (req, res, next) => {
        console.log("***User Service Logs Starts Here***");
        console.log(
            "Request Type %s for %s on %s from ",
            req.method,
            req.url,
            new Date()
        );
        console.log("Request Headers: ", req.headers);
        console.log("Request Body: ", req.body);
        console.log("Request Files: ", req.files);
        console.log("***User Service Logs Ends Here***");
        next();
    });
}

/* Registered routes here */
require('./routes')(app);

// Server listens to given port
app.listen(process.env.APPLICATION_PORT, (res, err) => {
    if (err) {
        onError(err);
    }
    console.log("Environment: " + process.env.APPLICATION_ENV);
    console.log("Application is running on the port:" + process.env.APPLICATION_PORT);
});

// Handles specific listen errors with friendly messages
function onError(error) {
    switch (error.code) {
        case 'EACCES':
            console.log(process.env.APPLICATION_PORT + ' requires elevated privileges')
            process.exit(1)
        case 'EADDRINUSE':
            console.log(process.env.APPLICATION_PORT + ' is already in use')
            process.exit(1)
        default:
            throw error
    }
}