Using routes in Express-js - node.js

So I'm starting to use Node.js. I saw the video with Ryan Dahl on Nodejs.org and heard he recommended Express-js for websites.
I downloaded the latest version of Express, and began to code. I have a fully fledged static view up on /, but as soon as I try sending parameters, I get errors like this:
Cannot GET /wiki
I tried following the guide on expressjs.com but the way one uses routes has changed in the latest version, which makes the guide unusable.
Guide:
app.get('/users/:id?', function(req, res, next){
var id = req.params.id;
if (id) {
// do something
} else {
next();
}
});
Generated by Express:
app.get('/', routes.index);
My problem arises when I try and add another route.
app.get('/wiki', routes.wiki_show);
I've tried a bunch of approaches, but I keep getting the Cannot GET /wiki (404) error.
routes/index.js looks like this:
exports.index = function(req, res) {
res.render('index', { title: 'Test', articles: articles, current_article: current_article, sections: sections })
};
The only thing I did there was add some parameters (arrays in the same file) and this i working. But when I copy the contents and change exports.index to exports.wiki or exports.wiki_show I still get the Cannot GET /wiki error.
Can anyone explain to me what I'm missing here? - Thanks.

So, after I created my question, I got this related list on the right with a similar issue: Organize routes in Node.js.
The answer in that post linked to the Express repo on GitHub and suggests to look at the 'route-separation' example.
This helped me change my code, and I now have it working. - Thanks for your comments.
My implementation ended up looking like this;
I require my routes in the app.js:
var express = require('express')
, site = require('./site')
, wiki = require('./wiki');
And I add my routes like this:
app.get('/', site.index);
app.get('/wiki/:id', wiki.show);
app.get('/wiki/:id/edit', wiki.edit);
I have two files called wiki.js and site.js in the root of my app, containing this:
exports.edit = function(req, res) {
var wiki_entry = req.params.id;
res.render('wiki/edit', {
title: 'Editing Wiki',
wiki: wiki_entry
})
}

The route-map express example matches url paths with objects which in turn matches http verbs with functions. This lays the routing out in a tree, which is concise and easy to read. The apps's entities are also written as objects with the functions as enclosed methods.
var express = require('../../lib/express')
, verbose = process.env.NODE_ENV != 'test'
, app = module.exports = express();
app.map = function(a, route){
route = route || '';
for (var key in a) {
switch (typeof a[key]) {
// { '/path': { ... }}
case 'object':
app.map(a[key], route + key);
break;
// get: function(){ ... }
case 'function':
if (verbose) console.log('%s %s', key, route);
app[key](route, a[key]);
break;
}
}
};
var users = {
list: function(req, res){
res.send('user list');
},
get: function(req, res){
res.send('user ' + req.params.uid);
},
del: function(req, res){
res.send('delete users');
}
};
var pets = {
list: function(req, res){
res.send('user ' + req.params.uid + '\'s pets');
},
del: function(req, res){
res.send('delete ' + req.params.uid + '\'s pet ' + req.params.pid);
}
};
app.map({
'/users': {
get: users.list,
del: users.del,
'/:uid': {
get: users.get,
'/pets': {
get: pets.list,
'/:pid': {
del: pets.del
}
}
}
}
});
app.listen(3000);

Seems that only index.js get loaded when you require("./routes") .
I used the following code in index.js to load the rest of the routes:
var fs = require('fs')
, path = require('path');
fs.readdirSync(__dirname).forEach(function(file){
var route_fname = __dirname + '/' + file;
var route_name = path.basename(route_fname, '.js');
if(route_name !== 'index' && route_name[0] !== "."){
exports[route_name] = require(route_fname)[route_name];
}
});

You could also organise them into modules. So it would be something like.
./
controllers
index.js
indexController.js
app.js
and then in the indexController.js of the controllers export your controllers.
//indexController.js
module.exports = function(){
//do some set up
var self = {
indexAction : function (req,res){
//do your thing
}
return self;
};
then in index.js of controllers dir
exports.indexController = require("./indexController");
and finally in app.js
var controllers = require("./controllers");
app.get("/",controllers.indexController().indexAction);
I think this approach allows for clearer seperation and also you can configure your controllers by passing perhaps a db connection in.

No one should ever have to keep writing app.use('/someRoute', require('someFile')) until it forms a heap of code.
It just doesn't make sense at all to be spending time invoking/defining routings. Even if you do need custom control, it's probably only for some of the time, and for the most bit you want to be able to just create a standard file structure of routings and have a module do it automatically.
Try Route Magic
As you scale your app, the routing invocations will start to form a giant heap of code that serves no purpose. You want to do just 2 lines of code to handle all the app.use routing invocations with Route Magic like this:
const magic = require('express-routemagic')
magic.use(app, __dirname, '[your route directory]')
For those you want to handle manually, just don't use pass the directory to Magic.

Related

node.js export variables across files

I'm relatively new to web development, brand new to node.js.
I'm trying to use express to make a site that updates an api with the chef-node api client, using this tutorial
If I create a stand alone node.js app, it works as expected, and the value 'bacon' is set to 'good'
app1.js
var fs = require('fs'),
chef = require('chef'),
key = fs.readFileSync('/Users/foo.pem'),
chef_client = chef.createClient('foo', key, 'https://chef.example.com/organizations/dev');
var mybreakfast = { "id":"food","bacon":"good"}
chef_client.put('/data/breakfast/food', mybreakfast, function(err,res,body) {
if (err) { return console.log(err); }
console.log(body)
});
Full code is here.
The app basically looks like this:
app.js
var fs = require('fs'),
chef = require('chef'),
key = fs.readFileSync('/Users/foo.pem'),
chef_client = chef.createClient('foo', key, 'https://chef.example.com/organizations/dev');
...
//tutorial says this isn't ideal, but it is quickest way to get working
app.use(function(req,res,next){
req.client = chef_client;
next();
});
routes/index.js
var express = require('express');
var router = express.Router();
/* GET home page. */
router.get('/', function(req, res, next) {
res.render('index', { title: 'Express' });
});
router.get('/databags', function(req, res) {
req.client.get('/data/breakfast/food', function(err,res,body) {
if (err) { return console.log(err); }
console.log("Found breakfast")
console.log(body)
bag_data = body; //TODO: Global variable is bad and you should feel bad, how do I use correct variable?
});
res.render('databags.jade', { title: 'Databags', somedata: bag_data });
});
router.post('/databags', function(req, res) {
var mybreakfast = { "id":"food","bacon":"good"}
req.client.put('/data/breakfast/food', mybreakfast, function(err,res,body) {
if (err) { return console.log(err); }
console.log(body)
});
});
vies/databags.jade
html
body
form(action='/databags', id='derp', method='POST')
each value, key in somedata
label #{key}
input(type='text',name="#{key}", value="#{value}")
br
br
input(type='submit', value='Submit', form='derp')
When I press the submit button in /databags, I get a 301 and no data is uploaded.
<html>
<head><title>301 Moved Permanently</title></head>
<body bgcolor="white">
<center><h1>301 Moved Permanently</h1></center>
<hr><center>openresty/1.7.10.1</center>
</body>
</html>
I suspect the problem has to do with the fact that I'm adding client to every request.
//tutorial says this isn't ideal, but it is quickest way to get working
app.use(function(req,res,next){
req.client = chef_client;
next();
});
What is the proper way to make the chef_client variable in app.js available in routes/index.js?
If that is the correct way to do this, then what could be making the app work by itself, but not when used with the express framework?
Since this is my first node.js / express site, any other suggestions to get this app working would be very appreciated.
Update
Solution has been found, working code snippet available here: https://gist.github.com/spuder/1e39868b6a9a0c3cdb13
If route_index.js is your routes/index.js then your problem is that you're not actually exporting anything from it. When you require('routes/index') you're going to get back whatever you set module.exports to to in that file.
That means your routes/index.js file should end with:
module.exports = router;
To address your question regarding how to share chef_client without a global, you can return a factory from routes/index.js that returns an instantiated router using the parameters you pass to it. That would look something like this:
routes/chef.js
function addChefRoutes(router, chefClient) {
router.get('databags', function(res,req){
// ...
}
});
module.exports = addChefRoutes;
app.js
var chefClient = chef.createClient('foo', key, 'https://chef.example.com/organizations/dev');
var addChefRoutes = require('./routes/chef');
var router = express.Router();
addChefRoutes(router, chefClient);

Express Routes in Parse Cloud Code Module

I am using parse.com cloud code with express to setup my routes. I have done this in the past with node, and I have my routes in separate files. So, in node I do
app.js
express = require("express");
app = exports.app = express();
require("./routes/js/account");
account.js
app = module.parent.exports.app;
app.get("/api/account/twitter", passport.authenticate("twitter"));
All the examples on parses site https://parse.com/docs/cloud_code_guide#webapp show this being done as follows.
app.js
var express = require('express');
var app = express();
app.get('/hello', function(req, res) {
res.render('hello', { message: 'Congrats, you just set up your app!' });
});
So, I would like to change the bottom to include a routes folder with separate routes files, but am not sure how to do this in parse.
I know this post is a little old, but I just wanted to post a solution for anyone still looking to get this to work.
What you need to do, is create your route file, I keep them in 'routes' forlder, for example <my_app_dir>/cloud/routes/user.js
Inside user.js you will have something that looks like this:
module.exports = function(app) {
app.get("/users/login", function(req, res) {
.. do your custom logic here ..
});
app.get("/users/logout", function(req, res) {
.. do your custom logic here ..
});
}
Then, in app.js you just include your file, but remember that you need to append cloud to the path, and pass the reference to your app instance:
require('cloud/routes/user')(app);
Also, remember that express evaluates routes in order, so you should take that into consideration when importing several route files.
I'm using a different method, have the routes in app.js, but you can probably include them in file if you prefer. Take a look at the example app,
anyblog on github
The way it works:
Set up a controller:
// Controller code in separate files.
var postsController = require('cloud/controllers/posts.js');
Add the controller route
// Show all posts on homepage
app.get('/', postsController.index);
// RESTful routes for the blog post object.
app.get('/posts', postsController.index);
app.get('/posts/new', postsController.new);
And then in posts.js, you can use exports, ex.
var Post = Parse.Object.extend('Post');
// Display all posts.
exports.index = function(req, res) {
var query = new Parse.Query(Post);
query.descending('createdAt');
query.find().then(function(results) {
res.render('posts/index', {
posts: results
});
},
function() {
res.send(500, 'Failed loading posts');
});
};
// Display a form for creating a new post.
exports.new = function(req, res) {
res.render('posts/new', {});
};
Pass the app reference to the post controller, and add the routes from there

Calling already defined routes in other routes in Express NodeJS

I am writing a web app in node.js using Express. I have defined a route as follows:
app.get("/firstService/:query", function(req,res){
//trivial example
var html = "<html><body></body></html>";
res.end(html)
});
How do I reuse that route from within express?
app.get("/secondService/:query", function(req,res){
var data = app.call("/firstService/"+query);
//do something with the data
res.end(data);
});
I couldn't find anything in the API documentation and would rather not use another library like "request" because that seems kludgey. I am trying to keep my app as modular as possible. Thoughts?
Thanks
Similar to what Gates said, but I would keep the function(req, res){} in your routes file. So I would do something like this instead:
routes.js
var myModule = require('myModule');
app.get("/firstService/:query", function(req,res){
var html = myModule.firstService(req.params.query);
res.end(html)
});
app.get("/secondService/:query", function(req,res){
var data = myModule.secondService(req.params.query);
res.end(data);
});
And then in your module have your logic split up like so:
myModule.js
var MyModule = function() {
var firstService= function(queryParam) {
var html = "<html><body></body></html>";
return html;
}
var secondService= function(queryParam) {
var data = firstService(queryParam);
// do something with the data
return data;
}
return {
firstService: firstService
,secondService: secondService
}
}();
module.exports = MyModule;
Can you simply break this out into another function, put it in a shared spot and go from there?
var queryHandler = require('special_query_handler');
// contains a method called firstService(req, res);
app.get('/firstService/:query', queryHandler.firstService);
// second app
app.get('/secondService/:query', queryHandler.secondService);
Honestly, this whole business of nesting the call back inside of the app.get(...) is not really a great practice. You end up with a giant file containing all of the core code.
What you really want is a file filled with app.get() and app.post() statements with all of the callback handlers living in different, better organized files.
If you have a lot of middleware on your route, you can benefit from spreading:
const router = express.Router();
const myMiddleware = [
authenticationMiddleware(),
validityCheckMiddleware(),
myActualRequestHandler
];
router.get( "/foo", ...myMiddleware );
router.get( "/v1/foo", ...myMiddleware );
You can use run-middleware module exactly for that
app.runMiddleware('/firstService/query',function(responseCode,body,headers){
// Your code here
})
More info:
Module page in Github & NPM;
Examples of use run-middleware module
Disclosure: I am the maintainer & first developer of this module.
I have used following way:
at userpage.js
router.createSitemap = function(req, res, callback) { code here callback(value); }
at product.js
var userPageRouter = require('userpages');
userPageRouter.createSitemap(req, res, function () {
//console.log('sitemap');
});
Also can use in same userpage.js router I can use for other routing as well. eg.
router.get('/sitemap', function (req, res, next) {
router.createSitemap(req, res, function () {
res.redirect('/sitemap.xml');
}); });
Hope this will help.

Pass variable to expressjs 3 routes

I have an ExpressJS 3 app and have my routes in a separate file. I'd like to declare some configs in my app.js that are available in the routes file - outside of the route definitions themselves.
In my app.js I would like to do something such as:
app.set('path_to_models', '/path/models/');
Then in my routes/index.js file I would like to be able to do this:
var Product = require(app.get('path_to_models') + 'product');
exports.list = function(req, res){
return Product.find(function (err, products) {
if (!err) {
res.render('product/manage', { products: products });
} else {
res.render('5xx');
}
});
};
I've seen a few posts related to this but none really addressed what I am looking for. I know that I can wrap the routes in a function but would like an alternative way that will keep my code as is if at all possible.
I just make a separate config module that holds my configuration and in any module that needs info from the config, I just require it as normal. Why drag express into the mix when a more loosely coupled approach works just fine.
config.js
exports.pathToModels = "/path/to/models";
routes.js
var config = require("./config");
console.log(config.pathToModels);
Simply pass app as an argument to `routes/index.js':
var routes = require('./routes/index.js')(app);
UPDATED: This should be
var routes = require('./routes/index.js').init(app);
and in routes/index.js:
var app;
exports=function(whichApp) {
UPDATED: This should be
exports.init=function(whichApp) {
app=whichApp;
// do initialization stuff
return exports;
}
exports.list=...

Node.js Express routing with MongoDB

Good afternoon,
I recently started working with Node.js + Express + MongoDB.
I set up a simple app containing :
/**
* Module dependencies.
*/
var express = require('express')
, routes = require('./routes')
, mongoose = require('mongoose')
, models = require('./models')
, Document
, db;
// lots of conf ...
models.defineModels(mongoose, function() {
app.Document = Document = mongoose.model('Document');
db = mongoose.connect(app.set('db-uri'));
})
// Routes
app.get('/', routes.home);
app.get('/documents.:format?', routes.list);
// classical end of app.js
I also have a corresponding 'index.js' file within a 'routes' folder, containing:
exports.home = function(req, res){
res.render('index', { title: 'Indx' })
};
exports.list = function(req, res){
Document.find().all(function(documents) {
switch (req.params.format) {
case 'json':
res.send(documents.map(function(d) {
return d.__doc;
}));
break;
default:
res.render('index', { title: 'Indx' });
}
});
};
The routing part is OK, meaning that when I point my browser to localhost:3000, I see the (Jade-template generated) 'index' view. When I point to localhost:3000/documents, the routing works OK, and the code is trying to serve the 'list' part of my 'index.js' route. However, I was hoping that the 'Document' mongoose model I created in the main app would be recognized within 'index.js', but this is clearly not the case as I keep getting the following error :
Express
500 ReferenceError: Document is not defined
at C:\PERSO\DEV\indxjs\routes\index.js:23:2
at callbacks (C:\PERSO\DEV\indxjs\node_modules\express\lib\router\index.js:272:11)
at param (C:\PERSO\DEV\indxjs\node_modules\express\lib\router\index.js:246:11)
at param (C:\PERSO\DEV\indxjs\node_modules\express\lib\router\index.js:243:11)
at pass (C:\PERSO\DEV\indxjs\node_modules\express\lib\router\index.js:253:5)
at Router._dispatch (C:\PERSO\DEV\indxjs\node_modules\express\lib\router\index.js:280:4)
at Object.handle (C:\PERSO\DEV\indxjs\node_modules\express\lib\router\index.js:45:10)
at next (C:\PERSO\DEV\indxjs\node_modules\express\node_modules\connect\lib\http.js:204:15)
at Object.methodOverride [as handle] (C:\PERSO\DEV\indxjs\node_modules\express\node_modules\connect\lib\middleware\methodOverride.js:35:5)
at next (C:\PERSO\DEV\indxjs\node_modules\express\node_modules\connect\lib\http.js:204:15)
I could obviously define my routing from within the 'app.js' with something like :
app.get('/documents.:format?', loadUser, function(req, res) {
// ...
}
But can anyone see a way of talking with mongoose while retaining the elegant './routes/index.js' separation from the 'app.js' ?
Thanks a lot
EDIT : following kind answer from Wes, I added the following code to 'index.js':
var Document;
function defineRoutes(mongoose, fn) {
Document = mongoose.model('Document');
fn();
}
exports.defineRoutes = defineRoutes;
// then the same as in initial post
And I enclosed the routing definitions within this function in 'app.js' :
routes.defineRoutes(mongoose, function() {
app.get('/', routes.home);
app.get('/documents.:format?', routes.list);
})
Everything is ok when I point to localhost:3000, but when I point to /documents, the browser keeps loading, loading ...
Thanks to Wes Johnson, I found my way out. I was blindly following a dated tutorial, which used deprecated methods from MongoDb. Below is the code snippet I finally used to implement the 'list documents' feature:
exports.list = function(req, res){
Document.find({},function(err, documents) {
switch (req.params.format) {
case 'json':
res.send(documents.map(function(d) {
return d.toObject();
}));
break;
default:
res.render('index', { title: 'Indx' });
}
});
};
Once again, thanks Wes !
Node modules are self-contained in terms of variable scope. Your Document object is not accessible from index.js as you mention. You need to pass this along to your routes logic, or pass along mongoose itself.
require calls are cached for the most part, so requiring mongoose in your index.js file and getting an instance of Document there is one option.
Since you don't really use Document in your app.js, you could always move the db configuration to another module and export the important references back to the scripts that need them.

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