This repository has been archived on 2018-10-12. You can view files and clone it, but cannot push or open issues or pull requests.
node-task/node_modules/express/lib/application.js
2014-09-18 15:35:58 -04:00

569 lines
12 KiB
JavaScript

/**
* Module dependencies.
*/
var finalhandler = require('finalhandler');
var flatten = require('./utils').flatten;
var mixin = require('utils-merge');
var Router = require('./router');
var methods = require('methods');
var middleware = require('./middleware/init');
var query = require('./middleware/query');
var debug = require('debug')('express:application');
var View = require('./view');
var http = require('http');
var compileETag = require('./utils').compileETag;
var compileQueryParser = require('./utils').compileQueryParser;
var compileTrust = require('./utils').compileTrust;
var deprecate = require('depd')('express');
var resolve = require('path').resolve;
var slice = Array.prototype.slice;
/**
* Application prototype.
*/
var app = exports = module.exports = {};
/**
* Initialize the server.
*
* - setup default configuration
* - setup default middleware
* - setup route reflection methods
*
* @api private
*/
app.init = function(){
this.cache = {};
this.settings = {};
this.engines = {};
this.defaultConfiguration();
};
/**
* Initialize application configuration.
*
* @api private
*/
app.defaultConfiguration = function(){
// default settings
this.enable('x-powered-by');
this.set('etag', 'weak');
var env = process.env.NODE_ENV || 'development';
this.set('env', env);
this.set('query parser', 'extended');
this.set('subdomain offset', 2);
this.set('trust proxy', false);
debug('booting in %s mode', env);
// inherit protos
this.on('mount', function(parent){
this.request.__proto__ = parent.request;
this.response.__proto__ = parent.response;
this.engines.__proto__ = parent.engines;
this.settings.__proto__ = parent.settings;
});
// setup locals
this.locals = Object.create(null);
// top-most app is mounted at /
this.mountpath = '/';
// default locals
this.locals.settings = this.settings;
// default configuration
this.set('view', View);
this.set('views', resolve('views'));
this.set('jsonp callback name', 'callback');
if (env === 'production') {
this.enable('view cache');
}
Object.defineProperty(this, 'router', {
get: function() {
throw new Error('\'app.router\' is deprecated!\nPlease see the 3.x to 4.x migration guide for details on how to update your app.');
}
});
};
/**
* lazily adds the base router if it has not yet been added.
*
* We cannot add the base router in the defaultConfiguration because
* it reads app settings which might be set after that has run.
*
* @api private
*/
app.lazyrouter = function() {
if (!this._router) {
this._router = new Router({
caseSensitive: this.enabled('case sensitive routing'),
strict: this.enabled('strict routing')
});
this._router.use(query(this.get('query parser fn')));
this._router.use(middleware.init(this));
}
};
/**
* Dispatch a req, res pair into the application. Starts pipeline processing.
*
* If no _done_ callback is provided, then default error handlers will respond
* in the event of an error bubbling through the stack.
*
* @api private
*/
app.handle = function(req, res, done) {
var router = this._router;
// final handler
done = done || finalhandler(req, res, {
env: this.get('env'),
onerror: logerror.bind(this)
});
// no routes
if (!router) {
debug('no routes defined on app');
done();
return;
}
router.handle(req, res, done);
};
/**
* Proxy `Router#use()` to add middleware to the app router.
* See Router#use() documentation for details.
*
* If the _fn_ parameter is an express app, then it will be
* mounted at the _route_ specified.
*
* @api public
*/
app.use = function use(fn) {
var offset = 0;
var path = '/';
var self = this;
// default path to '/'
// disambiguate app.use([fn])
if (typeof fn !== 'function') {
var arg = fn;
while (Array.isArray(arg) && arg.length !== 0) {
arg = arg[0];
}
// first arg is the path
if (typeof arg !== 'function') {
offset = 1;
path = fn;
}
}
var fns = flatten(slice.call(arguments, offset));
if (fns.length === 0) {
throw new TypeError('app.use() requires middleware functions');
}
// setup router
this.lazyrouter();
var router = this._router;
fns.forEach(function (fn) {
// non-express app
if (!fn || !fn.handle || !fn.set) {
return router.use(path, fn);
}
debug('.use app under %s', path);
fn.mountpath = path;
fn.parent = self;
// restore .app property on req and res
router.use(path, function mounted_app(req, res, next) {
var orig = req.app;
fn.handle(req, res, function (err) {
req.__proto__ = orig.request;
res.__proto__ = orig.response;
next(err);
});
});
// mounted an app
fn.emit('mount', self);
});
return this;
};
/**
* Proxy to the app `Router#route()`
* Returns a new `Route` instance for the _path_.
*
* Routes are isolated middleware stacks for specific paths.
* See the Route api docs for details.
*
* @api public
*/
app.route = function(path){
this.lazyrouter();
return this._router.route(path);
};
/**
* Register the given template engine callback `fn`
* as `ext`.
*
* By default will `require()` the engine based on the
* file extension. For example if you try to render
* a "foo.jade" file Express will invoke the following internally:
*
* app.engine('jade', require('jade').__express);
*
* For engines that do not provide `.__express` out of the box,
* or if you wish to "map" a different extension to the template engine
* you may use this method. For example mapping the EJS template engine to
* ".html" files:
*
* app.engine('html', require('ejs').renderFile);
*
* In this case EJS provides a `.renderFile()` method with
* the same signature that Express expects: `(path, options, callback)`,
* though note that it aliases this method as `ejs.__express` internally
* so if you're using ".ejs" extensions you dont need to do anything.
*
* Some template engines do not follow this convention, the
* [Consolidate.js](https://github.com/visionmedia/consolidate.js)
* library was created to map all of node's popular template
* engines to follow this convention, thus allowing them to
* work seamlessly within Express.
*
* @param {String} ext
* @param {Function} fn
* @return {app} for chaining
* @api public
*/
app.engine = function(ext, fn){
if ('function' != typeof fn) throw new Error('callback function required');
if ('.' != ext[0]) ext = '.' + ext;
this.engines[ext] = fn;
return this;
};
/**
* Proxy to `Router#param()` with one added api feature. The _name_ parameter
* can be an array of names.
*
* See the Router#param() docs for more details.
*
* @param {String|Array} name
* @param {Function} fn
* @return {app} for chaining
* @api public
*/
app.param = function(name, fn){
var self = this;
self.lazyrouter();
if (Array.isArray(name)) {
name.forEach(function(key) {
self.param(key, fn);
});
return this;
}
self._router.param(name, fn);
return this;
};
/**
* Assign `setting` to `val`, or return `setting`'s value.
*
* app.set('foo', 'bar');
* app.get('foo');
* // => "bar"
*
* Mounted servers inherit their parent server's settings.
*
* @param {String} setting
* @param {*} [val]
* @return {Server} for chaining
* @api public
*/
app.set = function(setting, val){
if (arguments.length === 1) {
// app.get(setting)
return this.settings[setting];
}
// set value
this.settings[setting] = val;
// trigger matched settings
switch (setting) {
case 'etag':
debug('compile etag %s', val);
this.set('etag fn', compileETag(val));
break;
case 'query parser':
debug('compile query parser %s', val);
this.set('query parser fn', compileQueryParser(val));
break;
case 'trust proxy':
debug('compile trust proxy %s', val);
this.set('trust proxy fn', compileTrust(val));
break;
}
return this;
};
/**
* Return the app's absolute pathname
* based on the parent(s) that have
* mounted it.
*
* For example if the application was
* mounted as "/admin", which itself
* was mounted as "/blog" then the
* return value would be "/blog/admin".
*
* @return {String}
* @api private
*/
app.path = function(){
return this.parent
? this.parent.path() + this.mountpath
: '';
};
/**
* Check if `setting` is enabled (truthy).
*
* app.enabled('foo')
* // => false
*
* app.enable('foo')
* app.enabled('foo')
* // => true
*
* @param {String} setting
* @return {Boolean}
* @api public
*/
app.enabled = function(setting){
return !!this.set(setting);
};
/**
* Check if `setting` is disabled.
*
* app.disabled('foo')
* // => true
*
* app.enable('foo')
* app.disabled('foo')
* // => false
*
* @param {String} setting
* @return {Boolean}
* @api public
*/
app.disabled = function(setting){
return !this.set(setting);
};
/**
* Enable `setting`.
*
* @param {String} setting
* @return {app} for chaining
* @api public
*/
app.enable = function(setting){
return this.set(setting, true);
};
/**
* Disable `setting`.
*
* @param {String} setting
* @return {app} for chaining
* @api public
*/
app.disable = function(setting){
return this.set(setting, false);
};
/**
* Delegate `.VERB(...)` calls to `router.VERB(...)`.
*/
methods.forEach(function(method){
app[method] = function(path){
if ('get' == method && 1 == arguments.length) return this.set(path);
this.lazyrouter();
var route = this._router.route(path);
route[method].apply(route, slice.call(arguments, 1));
return this;
};
});
/**
* Special-cased "all" method, applying the given route `path`,
* middleware, and callback to _every_ HTTP method.
*
* @param {String} path
* @param {Function} ...
* @return {app} for chaining
* @api public
*/
app.all = function(path){
this.lazyrouter();
var route = this._router.route(path);
var args = slice.call(arguments, 1);
methods.forEach(function(method){
route[method].apply(route, args);
});
return this;
};
// del -> delete alias
app.del = deprecate.function(app.delete, 'app.del: Use app.delete instead');
/**
* Render the given view `name` name with `options`
* and a callback accepting an error and the
* rendered template string.
*
* Example:
*
* app.render('email', { name: 'Tobi' }, function(err, html){
* // ...
* })
*
* @param {String} name
* @param {String|Function} options or fn
* @param {Function} fn
* @api public
*/
app.render = function(name, options, fn){
var opts = {};
var cache = this.cache;
var engines = this.engines;
var view;
// support callback function as second arg
if ('function' == typeof options) {
fn = options, options = {};
}
// merge app.locals
mixin(opts, this.locals);
// merge options._locals
if (options._locals) mixin(opts, options._locals);
// merge options
mixin(opts, options);
// set .cache unless explicitly provided
opts.cache = null == opts.cache
? this.enabled('view cache')
: opts.cache;
// primed cache
if (opts.cache) view = cache[name];
// view
if (!view) {
view = new (this.get('view'))(name, {
defaultEngine: this.get('view engine'),
root: this.get('views'),
engines: engines
});
if (!view.path) {
var err = new Error('Failed to lookup view "' + name + '" in views directory "' + view.root + '"');
err.view = view;
return fn(err);
}
// prime the cache
if (opts.cache) cache[name] = view;
}
// render
try {
view.render(opts, fn);
} catch (err) {
fn(err);
}
};
/**
* Listen for connections.
*
* A node `http.Server` is returned, with this
* application (which is a `Function`) as its
* callback. If you wish to create both an HTTP
* and HTTPS server you may do so with the "http"
* and "https" modules as shown here:
*
* var http = require('http')
* , https = require('https')
* , express = require('express')
* , app = express();
*
* http.createServer(app).listen(80);
* https.createServer({ ... }, app).listen(443);
*
* @return {http.Server}
* @api public
*/
app.listen = function(){
var server = http.createServer(this);
return server.listen.apply(server, arguments);
};
/**
* Log error using console.error.
*
* @param {Error} err
* @api public
*/
function logerror(err){
if (this.get('env') !== 'test') console.error(err.stack || err.toString());
}