Develop Reference

How do I reroute a GET request from my root in app.js to a route in my controllers folder in Express.js?

I'm basically trying to recreate this from Sinatra in Express:
get '/' do
redirect '/channels'
end
I'm trying to build a Node.js/Express.js app and am starting to incorporate an MVC structure. My app.js file contains my / route, as such:
app.js
app.get('/', function(req, res) {
res.redirect('/search');
})
I want it to redirect to the /search route in controllers/search.js, which contains the following:
controllers/search.js
const express = require('express');
const app = express();
app.get('/search', function(req, res) {
res.render('index.js');
})
The browser does redirect to localhost:3000/search but it displays Cannot GET /search. All of the tutorials and documentation I see about rerouting in Express don't show the whole file so I'm not able to tell if I have to require or export anything ala Node.js.
Any help is appreciated.

try this
server.js
var http = require('http');
var express = require('express');
var searchRouter = require('./searchRouter');
var app = express();
app.use('/', searchRouter);
var server = http.createServer(app);
server.listen(3000);
searchRouter.js
var express = require('express');
var router = express.Router();
router.get('/', function(req, res, next) {
res.send('Nope, try /search');
});
router.get('/search', function(req, res, next) {
res.send('yeah!! you found me');
});
module.exports = router;
you can extend this logic by
app.use('/search', searchRouter);
in search router
// this handles /search
router.get('/', function(req, res, next) {}
//this handles /search/apple
router.get('/:id', function(req, res, next) {}

Not sure how to relay requests to another router?

I have the following files
app.js
var express = require('express');
var app = express();
var api = require('./routes/api');
app.use('/api/v1/', api);
routes/api.js
var express = require('express');
var router = express.Router();
var users = require('./users');
router.get('/Users', users);
module.exports = router;
routes/users.js
var express = require('express');
var router = express.Router();
router.get('/')
.get(function(req, res) {
res.send('Hello world');
});
module.exports = router;
Why doesn't this work?

I think you should customise this by using separate routes file.
app.js
var express = require('express'),
app = express(),
routes = require('./routes'); // Create a routes folder and under that create index.js
app.use('/', routes);
routes/index.js
var express = require('express'),
router = express.Router(),
apis = require('apis');
router.get('YOUR API NAME', apis.api);
router.post('YOUR API NAME', apis.ANOTHER API HERE);
Create a folder apis and put your API under apis folder also create a index.js for exporting your APIs.
apis/index.js
var APIs = ['api', 'ADD MORE APIs here'];
APIs.forEach(function(api) {
module.exports[api] = require(__dirname + '/' + api)[api];
});
hope this will help you : )

In routes/users.js
Instead of
router.get('/')
.get(function(req, res) {
res.send('Hello world');
});
Try
router.get('/',function(req, res) {
res.send('Hello world');
});
Or
router.route('/')
.get(function(req, res) {
res.send('Hello world');
});

Using router.use instead of router.get in api.js fixed it for me

Express subrouter returns 404

I have this router (http/api/ping.js):
var express = require('express');
var router = express.Router();
router.get('/ping', function (req, res) {
res.send("You called /api/ping");
});
module.exports = router;
This router is embedded into this router (http/api/index.js):
var express = require('express');
var router = express.Router();
router.get('/', function (req, res) {
res.send('You called /api');
});
router.use('/ping', require('./ping'));
module.exports = router;
And this router is used by my Express.js app (app.js):
var http = require('http');
var express = require('express');
var bodyParser = require('body-parser');
var logger = require('./config').logger;
// Create app
var app = express();
var server = http.createServer(app)
var io = require('socket.io')(server);
// App config
app.use(bodyParser.json());
app.use('/api', require('./http/api'));
// Display requests on console
app.use(function (req, res, next) {
logger.trace(req.method, req._parsedUrl.href);
next()
});
module.exports = {
app: app,
server: server
};
When I run the app, /api returns You called /api, but /api/ping gives me a 404.
I am using Node 6.9.1 and Express ^4.14.0

I think order matters in this scenario. Try putting /ping above the / get route.
router.use('/ping', require('./ping'));
router.get('/', function (req, res) {
res.send('You called /api');
});
Also in your ping route you say the path to your route is /ping you also say it is /ping when you import it to the other router, which would make the path /api/ping/ping
change
router.get('/ping', function (req, res) {
res.send("You called /api/ping");
});
to
router.get('/', function (req, res) {
res.send("You called /api/ping");
});

I think your routing is incorrect on this line
router.use('/ping', require('./ping'));
this will point to http/api/ping/ping
it should be
router.use('/', require('./ping'));

Using a router with Express and Node.js

I'm new to Node.js. I've pulled some code from examples, but somehow I've broken something :).
At this time, in my app.js file, I have a line that I think wires up Express with Node.js. That line looks like this:
app.js
var routes = require('./routes/index');
// ...
app.get('/', routes.router);
Then, in ./routes/index.js I have the following:
routes/index.js
var express = require('express');
var router = express.Router();
/* GET home page */
router.get('/', function(req, res) {
res.send('respond with a resource');
});
module.exports = router;
When I run this, I get the following error:
Error: Route.get() requires callback functions but got a [object Undefined]
at Route.(anonymous function) [as get]
I don't understand. What am I doing wrong?
Thanks!

app.js
var routes = require('./routes/index');
//var routes = require('./routes') --> this works
// ...
app.use('/', routes); //Using the router instance as a middleware , relative to '/'
routes/index.js
var express = require('express');
var router = express.Router(); // new instance of Router
/* GET home page */
router.get('/', function(req, res) {
res.send('respond with a resource');
});
module.exports = router; // You export the intance
UPDATE
if you want more than 1 route file
app.js
var routes = require('./routes')
app
.use("/user",routes.user)
.use("/other",routes.other)
routes/index.js
module.exports = {
user : require(./user),
other : require(./other)
}
routes/user.js
var router = require("express").Router()
router.get("/",function (req,res){
// GET /user
})
.post("/",function (req,res){
//POST /user
})
module.exports = router;
routes/other.js
var router = require("express").Router()
router.get("/",function (req,res){
// GET /other
})
.post("/",function (req,res){
//POST /other
})
module.exports = router;

An example of a basic server.js:
var express = require('express');
var app = express();
app.get('/', function(req, res) {
res.sendfile(__dirname + '/client/views/index.html');
});
app.listen(3000, function() {
console.log('Server running on localhost:3000');
});
Comparing, I believe you need to listen to the port. Also I think your res.send should be sending an actual file.
More documentation on Nodejs here:
https://nodejs.org/api/
Also found a related questions on SO:
Node Route.get() requires callback function but got a [object undefined]

Router.use requires middleware function?

So I'm trying to seperate my login routes in a seperate JS file called login_routes.js
I keep getting this specific error:
TypeError: Router.use() requires middleware function but got a Object
at Function. (/Users/ethanthomas/Desktop/mean-stuff/express-server/node_modules/express/lib/router/index.js:446:13)
Not entirely understanding what it's asking me to implement?
login_routes.js:
var express = require('express');
var app = express();
app.route('/login')
.get(function(req, res, next) {
res.send('this is the login form');
})
.post(function(req, res, next) {
console.log('processing');
res.send('proccessing the login form!');
});
server.js:
var express = require('express');
var app = express();
var path = require('path');
var adminRoutes = require('./app/routes/admin_routes');
var loginRoutes = require('./app/routes/login_routes');
app.use('/admin', adminRoutes);
app.use('/login', loginRoutes);
//send our index.html file to the user for the home page
app.get('/', function(req, res) {
res.sendFile(path.join(__dirname + '/index.html'));
});
//start the server
app.listen(1337);
console.log('leet is the magic port');

Your login_routes.js should look something like this (in the context of express):
var express = require('express');
var router = express.Router();
// GET request to /login
router.get('/', function(req, res, next) {
// do something
});
// POST request to /login
router.post('/', function(req, res, next) {
// do something
});
module.exports = router;
In your app.js you use
var login_routes = require('./login_routes');
...
app.use('/login', login_routes);
...
Have a look at the code generated by the express-generator module. That is a starting point for express webserver apps.

People have already offered hints at the solution in comments.
The first issue is that you need to export your "sub" app from login_routes.js. To do so, change this:
var app = express();
Into this:
var app = module.exports = express();
Secondly, you are—probably unintentionally—creating routes for GET /login/login and POST /login/login. To solve this, use this in login_routes.js:
app.route('/').get(...).post(...);
This is because the root path in your sub app (the one in login_routes.js) will get mapped to the path used in app.use() in your main app (server.js).

Do like this:
login_routes.js:
exports.get = function( req, res ) {
res.send('this is the login form');
};
exports.post = function( req, res ) {
console.log('processing');
res.send('proccessing the login form!');
};
server.js:
var loginRoutes = require('./app/routes/login_routes');
app.get('/login', loginRoutes.get);
app.put('/login', loginRoutes.post);

login_routes.js:
var express = require('express');
var app = express();
app.route('/login')
.get(function(req, res, next) {
res.send('this is the login form');
})
.post(function(req, res, next) {
console.log('processing');
res.send('proccessing the login form!');
});
module.exports = router;
just writ module.exports = router then it will be work