/*!
* serve-static
* Copyright(c) 2010 Sencha Inc.
* Copyright(c) 2011 TJ Holowaychuk
* Copyright(c) 2014-2016 Douglas Christopher Wilson
* MIT Licensed
*/
'use strict'
/**
* Module dependencies.
* @private
*/
var encodeUrl = require('encodeurl')
var escapeHtml = require('escape-html')
var parseUrl = require('parseurl')
var resolve = require('path').resolve
var send = require('send')
var url = require('url')
/**
* Module exports.
* @public
*/
module.exports = serveStatic
module.exports.mime = send.mime
/**
* @param {string} root
* @param {object} [options]
* @return {function}
* @public
*/
function serveStatic (root, options) {
if (!root) {
throw new TypeError('root path required')
}
if (typeof root !== 'string') {
throw new TypeError('root path must be a string')
}
// copy options object
var opts = Object.create(options || null)
// fall-though
var fallthrough = opts.fallthrough !== false
// default redirect
var redirect = opts.redirect !== false
// headers listener
var setHeaders = opts.setHeaders
if (setHeaders && typeof setHeaders !== 'function') {
throw new TypeError('option setHeaders must be function')
}
// setup options for send
opts.maxage = opts.maxage || opts.maxAge || 0
opts.root = resolve(root)
// construct directory listener
var onDirectory = redirect
? createRedirectDirectoryListener()
: createNotFoundDirectoryListener()
return function serveStatic (req, res, next) {
if (req.method !== 'GET' && req.method !== 'HEAD') {
if (fallthrough) {
return next()
}
// method not allowed
res.statusCode = 405
res.setHeader('Allow', 'GET, HEAD')
res.setHeader('Content-Length', '0')
res.end()
return
}
var forwardError = !fallthrough
var originalUrl = parseUrl.original(req)
var path = parseUrl(req).pathname
// make sure redirect occurs at mount
if (path === '/' && originalUrl.pathname.substr(-1) !== '/') {
path = ''
}
// create send stream
var stream = send(req, path, opts)
// add directory handler
stream.on('directory', onDirectory)
// add headers listener
if (setHeaders) {
stream.on('headers', setHeaders)
}
// add file listener for fallthrough
if (fallthrough) {
stream.on('file', function onFile () {
// once file is determined, always forward error
forwardError = true
})
}
// forward errors
stream.on('error', function error (err) {
if (forwardError || !(err.statusCode < 500)) {
next(err)
return
}
next()
})
// pipe
stream.pipe(res)
}
}
/**
* Collapse all leading slashes into a single slash
* @private
*/
function collapseLeadingSlashes (str) {
for (var i = 0; i < str.length; i++) {
if (str.charCodeAt(i) !== 0x2f /* / */) {
break
}
}
return i > 1
? '/' + str.substr(i)
: str
}
/**
* Create a minimal HTML document.
*
* @param {string} title
* @param {string} body
* @private
*/
function createHtmlDocument (title, body) {
return '\n' +
'\n' +
'\n' +
'\n' +
'' + title + '\n' +
'\n' +
'\n' +
'' + body + '
\n' +
'\n' +
'\n'
}
/**
* Create a directory listener that just 404s.
* @private
*/
function createNotFoundDirectoryListener () {
return function notFound () {
this.error(404)
}
}
/**
* Create a directory listener that performs a redirect.
* @private
*/
function createRedirectDirectoryListener () {
return function redirect (res) {
if (this.hasTrailingSlash()) {
this.error(404)
return
}
// get original URL
var originalUrl = parseUrl.original(this.req)
// append trailing slash
originalUrl.path = null
originalUrl.pathname = collapseLeadingSlashes(originalUrl.pathname + '/')
// reformat the URL
var loc = encodeUrl(url.format(originalUrl))
var doc = createHtmlDocument('Redirecting', 'Redirecting to ' + escapeHtml(loc))
// send redirect response
res.statusCode = 301
res.setHeader('Content-Type', 'text/html; charset=UTF-8')
res.setHeader('Content-Length', Buffer.byteLength(doc))
res.setHeader('Content-Security-Policy', "default-src 'none'")
res.setHeader('X-Content-Type-Options', 'nosniff')
res.setHeader('Location', loc)
res.end(doc)
}
}