I use express.js 4.2.0 on node 5.2.0.
At first I had in my app.js
var routes = require('./routes/form');
app.get('/', routes);
and in form.js
var routes = require('express').Router();
routes.get('/', function(req, res) {
res.render('form',{title:'Login',userField:'Username',passField:'Password',photos: photos});
});
module.exports = routes;
And it was working fine, I got to localhost:3000/ and I was getting the form.
Now I want to add some code, so when I visit localhost:3000/YY/download it automatically downloads an image acording to the YY, the id.
So now I have in the app.js
var routes = require('./routes/form');
var download = require('./routes/form');
app.set('multimedia', __dirname + '/public/multimedia');
app.get('/', routes);
app.get('/:id/download', download(app.get('multimedia')));
and in the form.js
var routes = require('express').Router();
routes.get('/', function(req, res) {
res.render('form',{title:'Login',userField:'Username',passField:'Password',photos: photos});
});
var download = function(dir){
return function(req,res,next){
var path;
if(req.params.id==='01')
{path = dir+ '/01.jpg';}
else
{path = dir+'/02.jpg';}
res.download(path);
}
}
module.exports = routes;
module.exports = download;
Visiting localhost:3000/YY/download works fine, but visitng localhost:3000/ does not work. GET is pending and eventually the page never loads.
Please help me to fix this, because I am confused.
Thanks a lot.
You're overwriting the .exports object in form.js when you do two calls to:
module.exports = routes;
module.exports = download;
So you're never exporting the router and express is getting confusing instructions (route partially matched, but it's not getting the router back).
If you really wanted to keep those two objects exportable, just do
module.exports.routes = routes;
module.exports.download = download;
and change any references to it accordingly (<obj>.routes etc.)
I also recommend moving the download() into your form.js route logic and not exposing it in app.js at all. :)
Related
UPDATE 2: I just noticed that if on the app file I change the line:
app.use('/', home);
to:
app.use('/anything', home);
then all of the sub routes "roots" work fine.
UPDATE 3: I just realized something else. A method on the home.js file that I did not originally include below since I didn't think was relevant turns out to be the cause of the problem.
router.get('/:adventureId', (req, res) => {
var data;
//Irrelevant content that sets data as a JSON object.
res.json(data);
});
Turns out that every single sub route "root" is passing through here and since on the other routes adventureId is undefined then data is just an empty JSON object.
So the real question is: If this router bound to "/" and the other "roots" are bound to "/adventure" and "/test" why are all of them going through "/:adventrueId"?
I have a very simple ExpressJS application on which all of the "roots" in each and every single route other than home are not being handled and they always display an empty JSON object on the page.
In some posts it was mentioned that it could be a caching issue since these routes always return a 304 status, but I've tried doing an "Empty cach and hard reload" on Chrome and even with the 200 status I still get a blank page with an empty JSON object displayed on it. I tried it with MS Edge and got the exact same behavior.
Here's what I have:
On my app file
var app = express();
var home = require('./routes/home');
var adventure = require('./routes/adventure');
var test = require('./routes/test');
app.use('/', home);
app.use('/adventure', adventure);
app.use('/test', test);
On home.js file:
var express = require('express');
var router = express.Router();
router.get('/', (req, res) => {
console.log("This works fine with http://localhost:3000.");
res.render('home');
});
router.get('/:adventureId', (req, res) => {
var data;
//Irrelevant content that sets data as a JSON object.
res.json(data);
});
module.exports = router;
On the adventure.js file:
var express = require('express');
var router = express.Router();
router.use('/:id', (req, res) => {
console.log("This works fine with http://localhost:3000/adventure/5.");
next();
});
router.get('/:id', (req, res) => {
console.log("This works fine with http://localhost:3000/adventure/5.");
res.render('adventure');
});
//I've also tried putting this before the other routes and the result is the same.
router.get('/', (req, res) => {
console.log("This is never written in the console with http://localhost:3000/adventure.");
res.send("This is never rendered in the page.");
});
On the test.js file:
var express = require('express');
var router = express.Router();
router.use('/', (req, res) => {
console.log("This is never written on the console with http://localhost:3000/test.");
res.send("Hello from the test root route");
});
module.exports = router;
In the ExpressJS Router documentation and every single blog and example I've found it says that this is how it should work so I am really at a loss here.
Thank you.
If this router bound to "/" and the other "roots" are bound to "/adventure" and "/test" why are all of them going through "/:adventrueId"?
Because Express doesn't match routes based on which one matches best, it matches on which one matches first.
In your case, the route /:advertureId was declared before the routes for /adventure or /test. And /adventure and /test both match /:advertureId, so the handler for that route is called.
If you want to prevent this, declare more specific routes first:
app.use('/adventure', adventure);
app.use('/test', test);
app.use('/', home);
After much going around, several updates on the question and banging my head against the keyboard I finally understood what the problem is:
By having the routers set up like this:
app.use('/', home);
app.use('/adventure', adventure);
app.use('/game', gameService);
app.use('/test', test);
and on the "home" router having this method signature:
router.get('/:adventureId', (req, res) => {
var data;
//Irrelevant content that sets data as a JSON object.
res.json(data);
});
Every single sub route "root" was being interpreted as the parameter of the previous method so:
/adventure
/test
/anything
would be handled as:
adventrueId = adventrue
adventureId = test
adventrueId = anything
The solution was to do this:
app.use('/adventure', adventure);
app.use('/game', gameService);
app.use('/test', test);
app.use('/', home);
And now everything works.
I am playing with node.js and I don't quite understand why something I set up is working in one instance but if I make a slight change it will not work in another instance.
in my app.js I have
app.use('/musicplayer', require('./routes/music/index'));
in my music\index.js I have
var express = require('express');
var router = express.Router();
router.use('/users', require('./users'));
module.exports = router;
in my users.js I have this - working version
var express = require('express');
var usersRouter = express.Router();
var sqllite3 = require('sqlite3').verbose();
usersRouter.get('/login', function(req, res, next) {
res.render('music/login', { title: 'Express' });
});
module.exports = usersRouter;
But I would like to encapsulate the routes I am defining into another function like this not working this just hangs the page.
Modified version of my users.js not working
var express = require('express');
var usersRouter = express.Router();
var sqllite3 = require('sqlite3').verbose();
var router = function () {
usersRouter.get('/login', function (req, res, next) {
res.render('music/login', {title: 'Express'});
});
return usersRouter;
}
module.exports = router;
In the console I can see it comes in tries the get and nevers gets routed I see this "GET /musicplayer/users/login - - ms - -".
I have even put a console.log right before the return in the anonymous function I created to know it is getting in there and that I am hooking the pathways up right from the parent routes. And I do hit that log action to the screen.
Any help or tips would be appreciated:)
PS in case you are wondering I am trying to separate out apps for different development work I want to play with. So that is why I am doing the sub routing with musicplayer/index.js instead of just putting everything in the app.js for declaring of my main routes.
Router.use() expects an instance of another Router. However your (non-working) module only returns a function.
Use this in your index.js to fix the issue:
router.use('/users', require('./users')());
I'm making a nodeJS module, and I want to use expressJS as a framework for it.
I'm trying to see, how I could go by, including a function inside and app.get(); and call it via another file, such as the actual app.
var express = require("express");
var app = express();
app.get("/", function (req, res) {
exports.type = function (text) {
console.log(req.ip);
console.log(text);
}
});
now when I use this, and i call it on the actual app like:
var web = require("directory_to_file");
var express = require("express");
var app = express();
var http = require("http").Server(app);
app.get("/", function (req, res) {
web.type("Hello, world");
});
http.listen(10022, function () {
console.log("server is up");
});
I get an error:
TypeError: Property 'type' of object #<Object> is not a function
anyone know a way to make it so I can call the function?
There are generally two things you want to export as a module - an API and a Middleware. The classic example of middleware is an authentication module. To do the middleware, just export the middleware. I tend to do a little more than that so I can configure the middleware later. Something along the lines of this:
module.exports = exports = function(config) {
// Do something with config here
return function(req, res, next) {
// your middleware here
};
};
You can then use your middleware in your main program like this:
var app = require('express')(),
mymodule = require('./mymodule');
var config = {}; // replace with whatever config you need
app.use(mymodule(config));
app.listen(process.env.PORT || 3000);
To implement an API, you will create a Router object, then attach your routes to the Router object. You can then "mount" your router in your main program. For example, you could have a file called 'myroutes.js' with the following contents:
var express = require('express'),
myroutes = express.Router();
myroutes.get('/foo', (req, res) => {
res.status(200).type('application/json').send({ myparam: 'foo' });
});
module.exports = exports = myroutes;
Have the following in your main program:
var app = require('express')(),
myroutes = require('./myroutes');
app.use('/api', require('./myroutes'));
app.listen(process.env.PORT || 3000);
Here, in 'myroutes.js', I'm defining a sub-route of /foo and then in the main program, I'm mounting that on /api - so I would access /api/foo to access that API.
In your directory_to_file you are only exporting on app.get('/') which will never be called.
You could add in your directory_to_file the following code
var express = require('express');
var router = express.Router();
router.get('/', function(req, server) {
console.log(req.ip);
});
module.exports = router;
And in your main file you could use app.use('/', web)
A short explanation:
You are creating a new express app / config in your directory_to_file file which won't be launched or used. So your app.get event won't be fired once.
That's why web.type is not a function. You are not exporting anything.
Use the way I provided. This is a commonly used method.
You could call the code I provided a "route". Create multiple routes / route files and include them in your main method.
Your code just looks confused. If I understand you correctly, what you are really trying to do (at least in Node/express terminology) is write your own middleware.
Express is designed with this in mind and it's pretty straightforward e.g.
ipLogger.js
module.exports = function(req, res, next) {
console.log(req.ip);
next();
}
app.js
var http = require("http")
, express = require("express");
, app = express()
, server = http.Server(app)
, ipLogger = require("./ipLogger.js");
app.use(ipLogger()); // log IP of all requests
// handle routes
server.listen(10022, function() {
console.log("server is up");
});
I'm building a web app with Express and Node and am trying to factor my routing so that I don't have hundreds of routes in the same file. This site serves different files within the projects directory, so I made a file in routes/ called projectRoutes.jsto handle the routing for project files:
var express = require('express');
module.exports = function() {
var functions = {}
functions.routeProject = function(req, res) {
res.render('pages/projects/' + req.params.string, function(err, html) {
if (err) {
res.send("Sorry! Page not found!");
} else {
res.send(html);
}
});
};
return functions;
}
Then, in my routes.js, I have this...
var projectRoutes = require("./projectRoutes");
router.get('/projects/:string', function(req, res) {
projectRoutes().routeProject(req, res);
});
Is there a better way to structure this functionality within projectRoutes.js? In other words, how can I configure projectRoutes.js so that I can write the follow line of code in index.js:
router.get('/projects/:string', projectRoutes.routeProject);
The above seems like the normal way to handle something like this, but currently the above line throws an error in Node that says the function is undefined.
Thanks for your help!
You should use the native express router, it was made to solve this exact problem! It essentially lets you create simplified nested routes in a modular way.
For each of your resources, you should separate out your routes into several modules named <yourResource>.js. Those modules would contain all of the routing code as well as any other configuration or necessary functions. Then you would attach them in index.js with:
var apiRoute = router.route('/api')
apiRoute.use('/< yourResource >', yourResourceRouter)
For example, if you had a resource bikes:
In index.js:
var apiRoute = router.route('/api')
, bikeRoutes = require('./bikes')
apiRoute.use('/bikes', bikeRoutes)
Then in bike.js:
var express = require('express')
, router = express.Router()
, bikeRoutes = router.route('/')
bikeRoutes.get(function (req, res) {
res.send('api GET request received')
});
module.exports = bikeRoutes
From there its easy to see that you can build many different resources and continually nest them.
A larger of example of connecting the routes in index.js would be:
var apiRoute = router.route('/api')
, bikeRoutes = require('./bikes')
, carRoutes = require('./cars')
, skateboardRoutes = require('./skateboards')
, rollerskateRoutes = require('./rollerskates')
// routes
apiRoute.use('/bikes', bikeRoutes)
apiRoute.use('/cars', carRoutes)
apiRoute.use('/skateboards', skateboardRoutes)
apiRoute.use('/rollerskates', rollerskateRoutes)
Each router would contain code similar to bikes.js. With this example its easy to see using express's router modularizes and makes your code base more manageable.
Another option is to use the Router object itself, instead of the Route object.
In Index.js:
//Load Routes
BikeRoutes = require('./routes/Bike.js');
CarRoutes = require('./routes/Car.js');
//Routers
var express = require('express');
var ApiRouter = express.Router();
var BikeRouter = express.Router();
var CarRouter = express.Router();
//Express App
var app = express();
//App Routes
ApiRouter.get('/Api', function(req, res){...});
ApiRouter.use('/', BikeRouter);
ApiRouter.use('/', CarRouter);
In Bike.js:
var express = require('express');
var router = express.Router();
router.get('/Bikes', function(req, res){...});
module.exports = router;
Similarly in Car.js
I have the following files
lib/pub
lib/pub/index.js
app.js
On App.js
I have:
// app.js
var express = require("express")
, app = express()
, router = express.Router()
;
...
router.use('/pub',require('./pub'));
and then on index.js
// pub/index.js
var express = require('express')
, router = express.Router()
;
console.log("file loaded successfully")
module.exports = function(){
router.get('/',function(req,res){
console.log("got the get request")
})
}
The problem I have when I do localhost/pub request, I never get the got the get request, no matter whatever I try to change the code around, trying to add pub to the path.
router.get('/',...
router.get('/pub',...
router.get('./pub,...
router.get('./',...
router.get('pub',...
etc...
None of those or any other silly way I have attempted work... I can never get the log to say yes I got the request...
What am I doing wrong ! (expressjs changes so frequently and radically, any web tutorials become redundant or any previous help others got)
(edited to reflect comments)
If you want to move your routes to an external file, use the following pattern:
app.js
var express = require('express');
var app = express();
require('./routes')(app);
routes.js
module.exports = function(app) {
app.get('/pub', function(req, res) {
console.log('got the get!');
res.end();
});
};