Render entire EJS views directory with Express.js

server.js

import express from 'express';
import fs from 'fs';

const server = express();

server.set('view engine', 'ejs');

function filesToRender(dir){
    function fileSubstring(file, dir){
        return file.substring(0, file.length - 4).replace(dir,'')
    }

    function readDirRecursive(dir, filelist) {
        let files = fs.readdirSync(dir);
        filelist = filelist || [];
        files.map(file => {
          if (fs.statSync(dir + '/' + file).isDirectory()) {
            filelist = readDirRecursive(dir + '/' + file, filelist);
          }
          else {
            filelist.push(dir + '/' + file);
          }
        });
        return filelist;
    }

    return readDirRecursive(dir).map((file) => {
        return fileSubstring(file, dir);
    });

}

function renderFile(file){
    server.get(file, (req, res) => {
        res.render(file.slice( 1 ));
    });
    if (file.slice(-5) === "index")
    {
        server.get(file.substring(0, file.length - 5), (req, res) => {
            res.render(file.slice( 1 ));
        });
    }
}

filesToRender("views").map(file => renderFile(file));