/*! * express * Copyright(c) 2009-2013 TJ Holowaychuk * Copyright(c) 2014-2015 Douglas Christopher Wilson * MIT Licensed */ 'use strict'; /** * Module dependencies. * @private */ var Buffer = require('safe-buffer').Buffer var contentDisposition = require('content-disposition'); var createError = require('http-errors') var deprecate = require('depd')('express'); var encodeUrl = require('encodeurl'); var escapeHtml = require('escape-html'); var http = require('http'); var isAbsolute = require('./utils').isAbsolute; var onFinished = require('on-finished'); var path = require('path'); var statuses = require('statuses') var merge = require('utils-merge'); var sign = require('cookie-signature').sign; var normalizeType = require('./utils').normalizeType; var normalizeTypes = require('./utils').normalizeTypes; var setCharset = require('./utils').setCharset; var cookie = require('cookie'); var send = require('send'); var extname = path.extname; var mime = send.mime; var resolve = path.resolve; var vary = require('vary'); /** * Response prototype. * @public */ var res = Object.create(http.ServerResponse.prototype) /** * Module exports. * @public */ module.exports = res /** * Module variables. * @private */ var charsetRegExp = /;\s*charset\s*=/; /** * Set status `code`. * * @param {Number} code * @return {ServerResponse} * @public */ res.status = function status(code) { if ((typeof code === 'string' || Math.floor(code) !== code) && code > 99 && code < 1000) { deprecate('res.status(' + JSON.stringify(code) + '): use res.status(' + Math.floor(code) + ') instead') } this.statusCode = code; return this; }; /** * Set Link header field with the given `links`. * * Examples: * * res.links({ * next: 'http://api.example.com/users?page=2', * last: 'http://api.example.com/users?page=5' * }); * * @param {Object} links * @return {ServerResponse} * @public */ res.links = function(links){ var link = this.get('Link') || ''; if (link) link += ', '; return this.set('Link', link + Object.keys(links).map(function(rel){ return '<' + links[rel] + '>; rel="' + rel + '"'; }).join(', ')); }; /** * Send a response. * * Examples: * * res.send(Buffer.from('wahoo')); * res.send({ some: 'json' }); * res.send('

some html

'); * * @param {string|number|boolean|object|Buffer} body * @public */ res.send = function send(body) { var chunk = body; var encoding; var req = this.req; var type; // settings var app = this.app; // allow status / body if (arguments.length === 2) { // res.send(body, status) backwards compat if (typeof arguments[0] !== 'number' && typeof arguments[1] === 'number') { deprecate('res.send(body, status): Use res.status(status).send(body) instead'); this.statusCode = arguments[1]; } else { deprecate('res.send(status, body): Use res.status(status).send(body) instead'); this.statusCode = arguments[0]; chunk = arguments[1]; } } // disambiguate res.send(status) and res.send(status, num) if (typeof chunk === 'number' && arguments.length === 1) { // res.send(status) will set status message as text string if (!this.get('Content-Type')) { this.type('txt'); } deprecate('res.send(status): Use res.sendStatus(status) instead'); this.statusCode = chunk; chunk = statuses.message[chunk] } switch (typeof chunk) { // string defaulting to html case 'string': if (!this.get('Content-Type')) { this.type('html'); } break; case 'boolean': case 'number': case 'object': if (chunk === null) { chunk = ''; } else if (Buffer.isBuffer(chunk)) { if (!this.get('Content-Type')) { this.type('bin'); } } else { return this.json(chunk); } break; } // write strings in utf-8 if (typeof chunk === 'string') { encoding = 'utf8'; type = this.get('Content-Type'); // reflect this in content-type if (typeof type === 'string') { this.set('Content-Type', setCharset(type, 'utf-8')); } } // determine if ETag should be generated var etagFn = app.get('etag fn') var generateETag = !this.get('ETag') && typeof etagFn === 'function' // populate Content-Length var len if (chunk !== undefined) { if (Buffer.isBuffer(chunk)) { // get length of Buffer len = chunk.length } else if (!generateETag && chunk.length < 1000) { // just calculate length when no ETag + small chunk len = Buffer.byteLength(chunk, encoding) } else { // convert chunk to Buffer and calculate chunk = Buffer.from(chunk, encoding) encoding = undefined; len = chunk.length } this.set('Content-Length', len); } // populate ETag var etag; if (generateETag && len !== undefined) { if ((etag = etagFn(chunk, encoding))) { this.set('ETag', etag); } } // freshness if (req.fresh) this.statusCode = 304; // strip irrelevant headers if (204 === this.statusCode || 304 === this.statusCode) { this.removeHeader('Content-Type'); this.removeHeader('Content-Length'); this.removeHeader('Transfer-Encoding'); chunk = ''; } // alter headers for 205 if (this.statusCode === 205) { this.set('Content-Length', '0') this.removeHeader('Transfer-Encoding') chunk = '' } if (req.method === 'HEAD') { // skip body for HEAD this.end(); } else { // respond this.end(chunk, encoding); } return this; }; /** * Send JSON response. * * Examples: * * res.json(null); * res.json({ user: 'tj' }); * * @param {string|number|boolean|object} obj * @public */ res.json = function json(obj) { var val = obj; // allow status / body if (arguments.length === 2) { // res.json(body, status) backwards compat if (typeof arguments[1] === 'number') { deprecate('res.json(obj, status): Use res.status(status).json(obj) instead'); this.statusCode = arguments[1]; } else { deprecate('res.json(status, obj): Use res.status(status).json(obj) instead'); this.statusCode = arguments[0]; val = arguments[1]; } } // settings var app = this.app; var escape = app.get('json escape') var replacer = app.get('json replacer'); var spaces = app.get('json spaces'); var body = stringify(val, replacer, spaces, escape) // content-type if (!this.get('Content-Type')) { this.set('Content-Type', 'application/json'); } return this.send(body); }; /** * Send JSON response with JSONP callback support. * * Examples: * * res.jsonp(null); * res.jsonp({ user: 'tj' }); * * @param {string|number|boolean|object} obj * @public */ res.jsonp = function jsonp(obj) { var val = obj; // allow status / body if (arguments.length === 2) { // res.jsonp(body, status) backwards compat if (typeof arguments[1] === 'number') { deprecate('res.jsonp(obj, status): Use res.status(status).jsonp(obj) instead'); this.statusCode = arguments[1]; } else { deprecate('res.jsonp(status, obj): Use res.status(status).jsonp(obj) instead'); this.statusCode = arguments[0]; val = arguments[1]; } } // settings var app = this.app; var escape = app.get('json escape') var replacer = app.get('json replacer'); var spaces = app.get('json spaces'); var body = stringify(val, replacer, spaces, escape) var callback = this.req.query[app.get('jsonp callback name')]; // content-type if (!this.get('Content-Type')) { this.set('X-Content-Type-Options', 'nosniff'); this.set('Content-Type', 'application/json'); } // fixup callback if (Array.isArray(callback)) { callback = callback[0]; } // jsonp if (typeof callback === 'string' && callback.length !== 0) { this.set('X-Content-Type-Options', 'nosniff'); this.set('Content-Type', 'text/javascript'); // restrict callback charset callback = callback.replace(/[^\[\]\w$.]/g, ''); if (body === undefined) { // empty argument body = '' } else if (typeof body === 'string') { // replace chars not allowed in JavaScript that are in JSON body = body .replace(/\u2028/g, '\\u2028') .replace(/\u2029/g, '\\u2029') } // the /**/ is a specific security mitigation for "Rosetta Flash JSONP abuse" // the typeof check is just to reduce client error noise body = '/**/ typeof ' + callback + ' === \'function\' && ' + callback + '(' + body + ');'; } return this.send(body); }; /** * Send given HTTP status code. * * Sets the response status to `statusCode` and the body of the * response to the standard description from node's http.STATUS_CODES * or the statusCode number if no description. * * Examples: * * res.sendStatus(200); * * @param {number} statusCode * @public */ res.sendStatus = function sendStatus(statusCode) { var body = statuses.message[statusCode] || String(statusCode) this.statusCode = statusCode; this.type('txt'); return this.send(body); }; /** * Transfer the file at the given `path`. * * Automatically sets the _Content-Type_ response header field. * The callback `callback(err)` is invoked when the transfer is complete * or when an error occurs. Be sure to check `res.headersSent` * if you wish to attempt responding, as the header and some data * may have already been transferred. * * Options: * * - `maxAge` defaulting to 0 (can be string converted by `ms`) * - `root` root directory for relative filenames * - `headers` object of headers to serve with file * - `dotfiles` serve dotfiles, defaulting to false; can be `"allow"` to send them * * Other options are passed along to `send`. * * Examples: * * The following example illustrates how `res.sendFile()` may * be used as an alternative for the `static()` middleware for * dynamic situations. The code backing `res.sendFile()` is actually * the same code, so HTTP cache support etc is identical. * * app.get('/user/:uid/photos/:file', function(req, res){ * var uid = req.params.uid * , file = req.params.file; * * req.user.mayViewFilesFrom(uid, function(yes){ * if (yes) { * res.sendFile('/uploads/' + uid + '/' + file); * } else { * res.send(403, 'Sorry! you cant see that.'); * } * }); * }); * * @public */ res.sendFile = function sendFile(path, options, callback) { var done = callback; var req = this.req; var res = this; var next = req.next; var opts = options || {}; if (!path) { throw new TypeError('path argument is required to res.sendFile'); } if (typeof path !== 'string') { throw new TypeError('path must be a string to res.sendFile') } // support function as second arg if (typeof options === 'function') { done = options; opts = {}; } if (!opts.root && !isAbsolute(path)) { throw new TypeError('path must be absolute or specify root to res.sendFile'); } // create file stream var pathname = encodeURI(path); var file = send(req, pathname, opts); // transfer sendfile(res, file, opts, function (err) { if (done) return done(err); if (err && err.code === 'EISDIR') return next(); // next() all but write errors if (err && err.code !== 'ECONNABORTED' && err.syscall !== 'write') { next(err); } }); }; /** * Transfer the file at the given `path`. * * Automatically sets the _Content-Type_ response header field. * The callback `callback(err)` is invoked when the transfer is complete * or when an error occurs. Be sure to check `res.headersSent` * if you wish to attempt responding, as the header and some data * may have already been transferred. * * Options: * * - `maxAge` defaulting to 0 (can be string converted by `ms`) * - `root` root directory for relative filenames * - `headers` object of headers to serve with file * - `dotfiles` serve dotfiles, defaulting to false; can be `"allow"` to send them * * Other options are passed along to `send`. * * Examples: * * The following example illustrates how `res.sendfile()` may * be used as an alternative for the `static()` middleware for * dynamic situations. The code backing `res.sendfile()` is actually * the same code, so HTTP cache support etc is identical. * * app.get('/user/:uid/photos/:file', function(req, res){ * var uid = req.params.uid * , file = req.params.file; * * req.user.mayViewFilesFrom(uid, function(yes){ * if (yes) { * res.sendfile('/uploads/' + uid + '/' + file); * } else { * res.send(403, 'Sorry! you cant see that.'); * } * }); * }); * * @public */ res.sendfile = function (path, options, callback) { var done = callback; var req = this.req; var res = this; var next = req.next; var opts = options || {}; // support function as second arg if (typeof options === 'function') { done = options; opts = {}; } // create file stream var file = send(req, path, opts); // transfer sendfile(res, file, opts, function (err) { if (done) return done(err); if (err && err.code === 'EISDIR') return next(); // next() all but write errors if (err && err.code !== 'ECONNABORTED' && err.syscall !== 'write') { next(err); } }); }; res.sendfile = deprecate.function(res.sendfile, 'res.sendfile: Use res.sendFile instead'); /** * Transfer the file at the given `path` as an attachment. * * Optionally providing an alternate attachment `filename`, * and optional callback `callback(err)`. The callback is invoked * when the data transfer is complete, or when an error has * occurred. Be sure to check `res.headersSent` if you plan to respond. * * Optionally providing an `options` object to use with `res.sendFile()`. * This function will set the `Content-Disposition` header, overriding * any `Content-Disposition` header passed as header options in order * to set the attachment and filename. * * This method uses `res.sendFile()`. * * @public */ res.download = function download (path, filename, options, callback) { var done = callback; var name = filename; var opts = options || null // support function as second or third arg if (typeof filename === 'function') { done = filename; name = null; opts = null } else if (typeof options === 'function') { done = options opts = null } // support optional filename, where options may be in it's place if (typeof filename === 'object' && (typeof options === 'function' || options === undefined)) { name = null opts = filename } // set Content-Disposition when file is sent var headers = { 'Content-Disposition': contentDisposition(name || path) }; // merge user-provided headers if (opts && opts.headers) { var keys = Object.keys(opts.headers) for (var i = 0; i < keys.length; i++) { var key = keys[i] if (key.toLowerCase() !== 'content-disposition') { headers[key] = opts.headers[key] } } } // merge user-provided options opts = Object.create(opts) opts.headers = headers // Resolve the full path for sendFile var fullPath = !opts.root ? resolve(path) : path // send file return this.sendFile(fullPath, opts, done) }; /** * Set _Content-Type_ response header with `type` through `mime.lookup()` * when it does not contain "/", or set the Content-Type to `type` otherwise. * * Examples: * * res.type('.html'); * res.type('html'); * res.type('json'); * res.type('application/json'); * res.type('png'); * * @param {String} type * @return {ServerResponse} for chaining * @public */ res.contentType = res.type = function contentType(type) { var ct = type.indexOf('/') === -1 ? mime.lookup(type) : type; return this.set('Content-Type', ct); }; /** * Respond to the Acceptable formats using an `obj` * of mime-type callbacks. * * This method uses `req.accepted`, an array of * acceptable types ordered by their quality values. * When "Accept" is not present the _first_ callback * is invoked, otherwise the first match is used. When * no match is performed the server responds with * 406 "Not Acceptable". * * Content-Type is set for you, however if you choose * you may alter this within the callback using `res.type()` * or `res.set('Content-Type', ...)`. * * res.format({ * 'text/plain': function(){ * res.send('hey'); * }, * * 'text/html': function(){ * res.send('

hey

'); * }, * * 'application/json': function () { * res.send({ message: 'hey' }); * } * }); * * In addition to canonicalized MIME types you may * also use extnames mapped to these types: * * res.format({ * text: function(){ * res.send('hey'); * }, * * html: function(){ * res.send('

hey

'); * }, * * json: function(){ * res.send({ message: 'hey' }); * } * }); * * By default Express passes an `Error` * with a `.status` of 406 to `next(err)` * if a match is not made. If you provide * a `.default` callback it will be invoked * instead. * * @param {Object} obj * @return {ServerResponse} for chaining * @public */ res.format = function(obj){ var req = this.req; var next = req.next; var keys = Object.keys(obj) .filter(function (v) { return v !== 'default' }) var key = keys.length > 0 ? req.accepts(keys) : false; this.vary("Accept"); if (key) { this.set('Content-Type', normalizeType(key).value); obj[key](req, this, next); } else if (obj.default) { obj.default(req, this, next) } else { next(createError(406, { types: normalizeTypes(keys).map(function (o) { return o.value }) })) } return this; }; /** * Set _Content-Disposition_ header to _attachment_ with optional `filename`. * * @param {String} filename * @return {ServerResponse} * @public */ res.attachment = function attachment(filename) { if (filename) { this.type(extname(filename)); } this.set('Content-Disposition', contentDisposition(filename)); return this; }; /** * Append additional header `field` with value `val`. * * Example: * * res.append('Link', ['', '']); * res.append('Set-Cookie', 'foo=bar; Path=/; HttpOnly'); * res.append('Warning', '199 Miscellaneous warning'); * * @param {String} field * @param {String|Array} val * @return {ServerResponse} for chaining * @public */ res.append = function append(field, val) { var prev = this.get(field); var value = val; if (prev) { // concat the new and prev vals value = Array.isArray(prev) ? prev.concat(val) : Array.isArray(val) ? [prev].concat(val) : [prev, val] } return this.set(field, value); }; /** * Set header `field` to `val`, or pass * an object of header fields. * * Examples: * * res.set('Foo', ['bar', 'baz']); * res.set('Accept', 'application/json'); * res.set({ Accept: 'text/plain', 'X-API-Key': 'tobi' }); * * Aliased as `res.header()`. * * @param {String|Object} field * @param {String|Array} val * @return {ServerResponse} for chaining * @public */ res.set = res.header = function header(field, val) { if (arguments.length === 2) { var value = Array.isArray(val) ? val.map(String) : String(val); // add charset to content-type if (field.toLowerCase() === 'content-type') { if (Array.isArray(value)) { throw new TypeError('Content-Type cannot be set to an Array'); } if (!charsetRegExp.test(value)) { var charset = mime.charsets.lookup(value.split(';')[0]); if (charset) value += '; charset=' + charset.toLowerCase(); } } this.setHeader(field, value); } else { for (var key in field) { this.set(key, field[key]); } } return this; }; /** * Get value for header `field`. * * @param {String} field * @return {String} * @public */ res.get = function(field){ return this.getHeader(field); }; /** * Clear cookie `name`. * * @param {String} name * @param {Object} [options] * @return {ServerResponse} for chaining * @public */ res.clearCookie = function clearCookie(name, options) { var opts = merge({ expires: new Date(1), path: '/' }, options); return this.cookie(name, '', opts); }; /** * Set cookie `name` to `value`, with the given `options`. * * Options: * * - `maxAge` max-age in milliseconds, converted to `expires` * - `signed` sign the cookie * - `path` defaults to "/" * * Examples: * * // "Remember Me" for 15 minutes * res.cookie('rememberme', '1', { expires: new Date(Date.now() + 900000), httpOnly: true }); * * // same as above * res.cookie('rememberme', '1', { maxAge: 900000, httpOnly: true }) * * @param {String} name * @param {String|Object} value * @param {Object} [options] * @return {ServerResponse} for chaining * @public */ res.cookie = function (name, value, options) { var opts = merge({}, options); var secret = this.req.secret; var signed = opts.signed; if (signed && !secret) { throw new Error('cookieParser("secret") required for signed cookies'); } var val = typeof value === 'object' ? 'j:' + JSON.stringify(value) : String(value); if (signed) { val = 's:' + sign(val, secret); } if (opts.maxAge != null) { var maxAge = opts.maxAge - 0 if (!isNaN(maxAge)) { opts.expires = new Date(Date.now() + maxAge) opts.maxAge = Math.floor(maxAge / 1000) } } if (opts.path == null) { opts.path = '/'; } this.append('Set-Cookie', cookie.serialize(name, String(val), opts)); return this; }; /** * Set the location header to `url`. * * The given `url` can also be "back", which redirects * to the _Referrer_ or _Referer_ headers or "/". * * Examples: * * res.location('/foo/bar').; * res.location('http://example.com'); * res.location('../login'); * * @param {String} url * @return {ServerResponse} for chaining * @public */ res.location = function location(url) { var loc = url; // "back" is an alias for the referrer if (url === 'back') { loc = this.req.get('Referrer') || '/'; } // set location return this.set('Location', encodeUrl(loc)); }; /** * Redirect to the given `url` with optional response `status` * defaulting to 302. * * The resulting `url` is determined by `res.location()`, so * it will play nicely with mounted apps, relative paths, * `"back"` etc. * * Examples: * * res.redirect('/foo/bar'); * res.redirect('http://example.com'); * res.redirect(301, 'http://example.com'); * res.redirect('../login'); // /blog/post/1 -> /blog/login * * @public */ res.redirect = function redirect(url) { var address = url; var body; var status = 302; // allow status / url if (arguments.length === 2) { if (typeof arguments[0] === 'number') { status = arguments[0]; address = arguments[1]; } else { deprecate('res.redirect(url, status): Use res.redirect(status, url) instead'); status = arguments[1]; } } // Set location header address = this.location(address).get('Location'); // Support text/{plain,html} by default this.format({ text: function(){ body = statuses.message[status] + '. Redirecting to ' + address }, html: function(){ var u = escapeHtml(address); body = '

' + statuses.message[status] + '. Redirecting to ' + u + '

' }, default: function(){ body = ''; } }); // Respond this.statusCode = status; this.set('Content-Length', Buffer.byteLength(body)); if (this.req.method === 'HEAD') { this.end(); } else { this.end(body); } }; /** * Add `field` to Vary. If already present in the Vary set, then * this call is simply ignored. * * @param {Array|String} field * @return {ServerResponse} for chaining * @public */ res.vary = function(field){ // checks for back-compat if (!field || (Array.isArray(field) && !field.length)) { deprecate('res.vary(): Provide a field name'); return this; } vary(this, field); return this; }; /** * Render `view` with the given `options` and optional callback `fn`. * When a callback function is given a response will _not_ be made * automatically, otherwise a response of _200_ and _text/html_ is given. * * Options: * * - `cache` boolean hinting to the engine it should cache * - `filename` filename of the view being rendered * * @public */ res.render = function render(view, options, callback) { var app = this.req.app; var done = callback; var opts = options || {}; var req = this.req; var self = this; // support callback function as second arg if (typeof options === 'function') { done = options; opts = {}; } // merge res.locals opts._locals = self.locals; // default callback to respond done = done || function (err, str) { if (err) return req.next(err); self.send(str); }; // render app.render(view, opts, done); }; // pipe the send file stream function sendfile(res, file, options, callback) { var done = false; var streaming; // request aborted function onaborted() { if (done) return; done = true; var err = new Error('Request aborted'); err.code = 'ECONNABORTED'; callback(err); } // directory function ondirectory() { if (done) return; done = true; var err = new Error('EISDIR, read'); err.code = 'EISDIR'; callback(err); } // errors function onerror(err) { if (done) return; done = true; callback(err); } // ended function onend() { if (done) return; done = true; callback(); } // file function onfile() { streaming = false; } // finished function onfinish(err) { if (err && err.code === 'ECONNRESET') return onaborted(); if (err) return onerror(err); if (done) return; setImmediate(function () { if (streaming !== false && !done) { onaborted(); return; } if (done) return; done = true; callback(); }); } // streaming function onstream() { streaming = true; } file.on('directory', ondirectory); file.on('end', onend); file.on('error', onerror); file.on('file', onfile); file.on('stream', onstream); onFinished(res, onfinish); if (options.headers) { // set headers on successful transfer file.on('headers', function headers(res) { var obj = options.headers; var keys = Object.keys(obj); for (var i = 0; i < keys.length; i++) { var k = keys[i]; res.setHeader(k, obj[k]); } }); } // pipe file.pipe(res); } /** * Stringify JSON, like JSON.stringify, but v8 optimized, with the * ability to escape characters that can trigger HTML sniffing. * * @param {*} value * @param {function} replacer * @param {number} spaces * @param {boolean} escape * @returns {string} * @private */ function stringify (value, replacer, spaces, escape) { // v8 checks arguments.length for optimizing simple call // https://bugs.chromium.org/p/v8/issues/detail?id=4730 var json = replacer || spaces ? JSON.stringify(value, replacer, spaces) : JSON.stringify(value); if (escape && typeof json === 'string') { json = json.replace(/[<>&]/g, function (c) { switch (c.charCodeAt(0)) { case 0x3c: return '\\u003c' case 0x3e: return '\\u003e' case 0x26: return '\\u0026' /* istanbul ignore next: unreachable default */ default: return c } }) } return json }