plex-web-downloader/node_modules/serve-favicon/index.js

178 lines
3.4 KiB
JavaScript

/*!
* serve-favicon
* Copyright(c) 2010 Sencha Inc.
* Copyright(c) 2011 TJ Holowaychuk
* Copyright(c) 2014-2015 Douglas Christopher Wilson
* MIT Licensed
*/
'use strict';
/**
* Module dependencies.
* @private
*/
var etag = require('etag');
var fresh = require('fresh');
var fs = require('fs');
var ms = require('ms');
var parseUrl = require('parseurl');
var path = require('path');
var resolve = path.resolve;
/**
* Module exports.
* @public
*/
module.exports = favicon;
/**
* Module variables.
* @private
*/
var maxMaxAge = 60 * 60 * 24 * 365 * 1000; // 1 year
/**
* Serves the favicon located by the given `path`.
*
* @public
* @param {String|Buffer} path
* @param {Object} [options]
* @return {Function} middleware
*/
function favicon(path, options) {
var opts = options || {};
var buf;
var icon; // favicon cache
var maxAge = calcMaxAge(opts.maxAge);
var stat;
if (!path) throw new TypeError('path to favicon.ico is required');
if (Buffer.isBuffer(path)) {
buf = new Buffer(path.length);
path.copy(buf);
icon = createIcon(buf, maxAge);
} else if (typeof path === 'string') {
path = resolve(path);
stat = fs.statSync(path);
if (stat.isDirectory()) throw createIsDirError(path);
} else {
throw new TypeError('path to favicon.ico must be string or buffer');
}
return function favicon(req, res, next){
if (parseUrl(req).pathname !== '/favicon.ico') {
next();
return;
}
if (req.method !== 'GET' && req.method !== 'HEAD') {
res.statusCode = req.method === 'OPTIONS' ? 200 : 405;
res.setHeader('Allow', 'GET, HEAD, OPTIONS');
res.setHeader('Content-Length', '0');
res.end();
return;
}
if (icon) return send(req, res, icon);
fs.readFile(path, function(err, buf){
if (err) return next(err);
icon = createIcon(buf, maxAge);
send(req, res, icon);
});
};
};
/**
* Calculate the max-age from a configured value.
*
* @private
* @param {string|number} val
* @return {number}
*/
function calcMaxAge(val) {
var num = typeof val === 'string'
? ms(val)
: val;
return num != null
? Math.min(Math.max(0, num), maxMaxAge)
: maxMaxAge
}
/**
* Create icon data from Buffer and max-age.
*
* @private
* @param {Buffer} buf
* @param {number} maxAge
* @return {object}
*/
function createIcon(buf, maxAge) {
return {
body: buf,
headers: {
'Cache-Control': 'public, max-age=' + Math.floor(maxAge / 1000),
'ETag': etag(buf)
}
};
}
/**
* Create EISDIR error.
*
* @private
* @param {string} path
* @return {Error}
*/
function createIsDirError(path) {
var error = new Error('EISDIR, illegal operation on directory \'' + path + '\'');
error.code = 'EISDIR';
error.errno = 28;
error.path = path;
error.syscall = 'open';
return error;
}
/**
* Send icon data in response to a request.
*
* @private
* @param {IncomingMessage} req
* @param {OutgoingMessage} res
* @param {object} icon
*/
function send(req, res, icon) {
var headers = icon.headers;
// Set headers
var keys = Object.keys(headers);
for (var i = 0; i < keys.length; i++) {
var key = keys[i];
res.setHeader(key, headers[key]);
}
if (fresh(req.headers, res._headers)) {
res.statusCode = 304;
res.end();
return;
}
res.statusCode = 200;
res.setHeader('Content-Length', icon.body.length);
res.setHeader('Content-Type', 'image/x-icon');
res.end(icon.body);
}