blob: ff1498b8cd74c6f2d917252b44b055e1aff40c47 [file] [log] [blame]
/*!
* Express - Router
* Copyright(c) 2010 TJ Holowaychuk <tj@vision-media.ca>
* MIT Licensed
*/
/**
* Module dependencies.
*/
var Route = require('./route')
, Collection = require('./collection')
, utils = require('../utils')
, parse = require('url').parse
, toArray = utils.toArray;
/**
* Expose `Router` constructor.
*/
exports = module.exports = Router;
/**
* Expose HTTP methods.
*/
var methods = exports.methods = require('./methods');
/**
* Initialize a new `Router` with the given `app`.
*
* @param {express.HTTPServer} app
* @api private
*/
function Router(app) {
var self = this;
this.app = app;
this.routes = {};
this.params = {};
this._params = [];
this.middleware = function(req, res, next){
self._dispatch(req, res, next);
};
}
/**
* Register a param callback `fn` for the given `name`.
*
* @param {String|Function} name
* @param {Function} fn
* @return {Router} for chaining
* @api public
*/
Router.prototype.param = function(name, fn){
// param logic
if ('function' == typeof name) {
this._params.push(name);
return;
}
// apply param functions
var params = this._params
, len = params.length
, ret;
for (var i = 0; i < len; ++i) {
if (ret = params[i](name, fn)) {
fn = ret;
}
}
// ensure we end up with a
// middleware function
if ('function' != typeof fn) {
throw new Error('invalid param() call for ' + name + ', got ' + fn);
}
(this.params[name] = this.params[name] || []).push(fn);
return this;
};
/**
* Return a `Collection` of all routes defined.
*
* @return {Collection}
* @api public
*/
Router.prototype.all = function(){
return this.find(function(){
return true;
});
};
/**
* Remove the given `route`, returns
* a bool indicating if the route was present
* or not.
*
* @param {Route} route
* @return {Boolean}
* @api public
*/
Router.prototype.remove = function(route){
var routes = this.routes[route.method]
, len = routes.length;
for (var i = 0; i < len; ++i) {
if (route == routes[i]) {
routes.splice(i, 1);
return true;
}
}
};
/**
* Return routes with route paths matching `path`.
*
* @param {String} method
* @param {String} path
* @return {Collection}
* @api public
*/
Router.prototype.lookup = function(method, path){
return this.find(function(route){
return path == route.path
&& (route.method == method
|| method == 'all');
});
};
/**
* Return routes with regexps that match the given `url`.
*
* @param {String} method
* @param {String} url
* @return {Collection}
* @api public
*/
Router.prototype.match = function(method, url){
return this.find(function(route){
return route.match(url)
&& (route.method == method
|| method == 'all');
});
};
/**
* Find routes based on the return value of `fn`
* which is invoked once per route.
*
* @param {Function} fn
* @return {Collection}
* @api public
*/
Router.prototype.find = function(fn){
var len = methods.length
, ret = new Collection(this)
, method
, routes
, route;
for (var i = 0; i < len; ++i) {
method = methods[i];
routes = this.routes[method];
if (!routes) continue;
for (var j = 0, jlen = routes.length; j < jlen; ++j) {
route = routes[j];
if (fn(route)) ret.push(route);
}
}
return ret;
};
/**
* Route dispatcher aka the route "middleware".
*
* @param {IncomingMessage} req
* @param {ServerResponse} res
* @param {Function} next
* @api private
*/
Router.prototype._dispatch = function(req, res, next){
var params = this.params
, self = this;
// route dispatch
(function pass(i, err){
var paramCallbacks
, paramIndex = 0
, paramVal
, route
, keys
, key
, ret;
// match next route
function nextRoute(err) {
pass(req._route_index + 1, err);
}
// match route
req.route = route = self._match(req, i);
// implied OPTIONS
if (!route && 'OPTIONS' == req.method) return self._options(req, res);
// no route
if (!route) return next(err);
// we have a route
// start at param 0
req.params = route.params;
keys = route.keys;
i = 0;
// param callbacks
function param(err) {
paramIndex = 0;
key = keys[i++];
paramVal = key && req.params[key.name];
paramCallbacks = key && params[key.name];
try {
if ('route' == err) {
nextRoute();
} else if (err) {
i = 0;
callbacks(err);
} else if (paramCallbacks && undefined !== paramVal) {
paramCallback();
} else if (key) {
param();
} else {
i = 0;
callbacks();
}
} catch (err) {
param(err);
}
};
param(err);
// single param callbacks
function paramCallback(err) {
var fn = paramCallbacks[paramIndex++];
if (err || !fn) return param(err);
fn(req, res, paramCallback, paramVal, key.name);
}
// invoke route callbacks
function callbacks(err) {
var fn = route.callbacks[i++];
try {
if ('route' == err) {
nextRoute();
} else if (err && fn) {
if (fn.length < 4) return callbacks(err);
fn(err, req, res, callbacks);
} else if (fn) {
fn(req, res, callbacks);
} else {
nextRoute(err);
}
} catch (err) {
callbacks(err);
}
}
})(0);
};
/**
* Respond to __OPTIONS__ method.
*
* @param {IncomingMessage} req
* @param {ServerResponse} res
* @api private
*/
Router.prototype._options = function(req, res){
var path = parse(req.url).pathname
, body = this._optionsFor(path).join(',');
res.send(body, { Allow: body });
};
/**
* Return an array of HTTP verbs or "options" for `path`.
*
* @param {String} path
* @return {Array}
* @api private
*/
Router.prototype._optionsFor = function(path){
var self = this;
return methods.filter(function(method){
var routes = self.routes[method];
if (!routes || 'options' == method) return;
for (var i = 0, len = routes.length; i < len; ++i) {
if (routes[i].match(path)) return true;
}
}).map(function(method){
return method.toUpperCase();
});
};
/**
* Attempt to match a route for `req`
* starting from offset `i`.
*
* @param {IncomingMessage} req
* @param {Number} i
* @return {Route}
* @api private
*/
Router.prototype._match = function(req, i){
var method = req.method.toLowerCase()
, url = parse(req.url)
, path = url.pathname
, routes = this.routes
, captures
, route
, keys;
// pass HEAD to GET routes
if ('head' == method) method = 'get';
// routes for this method
if (routes = routes[method]) {
// matching routes
for (var len = routes.length; i < len; ++i) {
route = routes[i];
if (captures = route.match(path)) {
keys = route.keys;
route.params = [];
// params from capture groups
for (var j = 1, jlen = captures.length; j < jlen; ++j) {
var key = keys[j-1]
, val = 'string' == typeof captures[j]
? decodeURIComponent(captures[j])
: captures[j];
if (key) {
route.params[key.name] = val;
} else {
route.params.push(val);
}
}
// all done
req._route_index = i;
return route;
}
}
}
};
/**
* Route `method`, `path`, and one or more callbacks.
*
* @param {String} method
* @param {String} path
* @param {Function} callback...
* @return {Router} for chaining
* @api private
*/
Router.prototype._route = function(method, path, callbacks){
var app = this.app
, callbacks = utils.flatten(toArray(arguments, 2));
// ensure path was given
if (!path) throw new Error('app.' + method + '() requires a path');
// create the route
var route = new Route(method, path, callbacks, {
sensitive: app.enabled('case sensitive routes')
, strict: app.enabled('strict routing')
});
// add it
(this.routes[method] = this.routes[method] || [])
.push(route);
return this;
};