Return a random image from a folder

index.js

const express = require('express');
const recursive = require('recursive-readdir');
const app = express();
const port = 3000;

var images = [];

app.get('/', (req, res) => {
    var image = images[Math.floor(Math.random() * images.length)];
    res.sendFile(image);
});

app.listen(port, () => {
    getFileList();
    console.log('listening on port ' + port)
});

getFileList = () => {
    var path = 'c:/temp';
    var regEx = /\.(gif|jpg|jpeg|tiff|png)$/i;
    recursive(path, (err, files) => {
        images = files.filter((value, index, array) => {
            return value.match(regEx);
        });

    });
}