/*!
* 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);
};
}