Simple static file server in express with authentication

app.coffee

express = require 'express'
fs = require 'fs'

app = express()

authenticationFilter = (req, res, next) ->
  auth_token = req.query.auth_token
  if auth_token == process.env.AUTH_TOKE
    next()
  else
    res.status(401).send('Forbiden')

app.use authenticationFilter

app.get '/*', (req, res) ->
  fileName = req.params
  fs.readFile "./static_files/#{fileName}", 'utf8', (err, data) ->
    if err
      res.status(404).send('Not found')
    else
      res.setHeader('Content-Type', 'text/plain')
      res.setHeader('Content-Length', data.length)
      res.end(data)

port = process.env.PORT || 9999
console.log "Listening on port #{port}"
app.listen port