In my app.js I'm passing on the request to the router like so
app.post('/validateUser', validationRoute)
In my route I'd normally do like this, to pass the request on to the controller, and call the appropriate function.
router.use('/', validationCon.validateUser)
My validateUser which is found in my controller, looks like this
module.exports = {
validateUser: async (req, res) => {
//const uName = req.body.uName,
//pwd = req.body.pwd;
const success = await logic.validateUser(uName, pwd);
if(success) {
//res.status(201).send('Login accepted');
res.render('../views/pages/secret')
}
else
res.status(400).send("Bad confidentials")
}
}
The issue I had by doing router.use('/', validationCon.validateUser) was that I didn't have the req and res to pass on to the controller, so these were undefined or null in my controller. So I changed my router to do:
router.use('/', (req, res, next) => {
//console.log("URL from validate: "+req.url, ' req.body: ', req.body)
username = req.body.username
pass = req.body.password
/* Now I want to pass these 2 values on to the controller*/
})
module.exports = router
Now I have the req and res objects in my route, and so I can access the values in the request body. But the issue I have now, is that I don't know how to pass these on to the controller, since I no longer do router.use('/', validationCon.validateUser)
How can I do so that I can access the req body in the controller? As you can see in the controller, I am also passing the values from the request body on to the model, so that they can be verified in the database.
I am not sure if this is the best approach of doing it, this is my first nodejs/express application, so I'm all ears if there are suggestions. Thanks
The req, res, next should be available at the controller too.
A better approach is to set the app to use routes, and specify post \ get at the route level.
See here
I've just made an Node.js app modular by splitting up data models and routes into separate files.
My routes are exported by express.Router(). In these routes I would like to import queried values from my app.js to be rendered with the templates.
How would I in the easiest way save things lets say with app.locals or req.variableName?
Since the route using express.Router() ties it together with app.js, should I be using app.params() and somehow make these values accessible?
Using globals seems like a worse idea as I'm scaling up the app. I'm not sure if best practice would be saving values to the process environment either using app.locals.valueKey = key.someValue...
Big thanks in advance to anyone
If I understand the question correctly, you want to pass a value to a later middleware:
app.js:
// Let's say it's like this in this example
var express = require('express');
var app = express();
app.use(function (req, res, next) {
var user = User.findOne({ email: 'someValue' }, function (err, user) {
// Returning a document with the keys I'm interested in
req.user = { key1: value1, key2: value2... }; // add the user to the request object
next(); // tell express to execute the next middleware
});
});
// Here I include the route
require('./routes/public.js')(app); // I would recommend passing in the app object
/routes/public.js:
module.export = function(app) {
app.get('/', function(req, res) {
// Serving Home Page (where I want to pass in the values)
router.get('/', function (req, res) {
// Passing in the values for Swig to render
var user = req.user; // this is the object you set in the earlier middleware (in app.js)
res.render('index.html', { pagename: user.key2, ... });
});
});
});
I am using express to make a web app in node.js. This is a simplification of what I have:
var express = require('express');
var jade = require('jade');
var http = require("http");
var app = express();
var server = http.createServer(app);
app.get('/', function(req, res) {
// Prepare the context
res.render('home.jade', context);
});
app.post('/category', function(req, res) {
// Process the data received in req.body
res.redirect('/');
});
My problem is the following:
If I find that the data sent in /category doesn't validate, I would like pass some additional context to the / page. How could I do this? Redirect doesn't seem to allow any kind of extra parameter.
There are a few ways of passing data around to different routes. The most correct answer is, of course, query strings. You'll need to ensure that the values are properly encodeURIComponent and decodeURIComponent.
app.get('/category', function(req, res) {
var string = encodeURIComponent('something that would break');
res.redirect('/?valid=' + string);
});
You can snag that in your other route by getting the parameters sent by using req.query.
app.get('/', function(req, res) {
var passedVariable = req.query.valid;
// Do something with variable
});
For more dynamic way you can use the url core module to generate the query string for you:
const url = require('url');
app.get('/category', function(req, res) {
res.redirect(url.format({
pathname:"/",
query: {
"a": 1,
"b": 2,
"valid":"your string here"
}
}));
});
So if you want to redirect all req query string variables you can simply do
res.redirect(url.format({
pathname:"/",
query:req.query,
});
});
And if you are using Node >= 7.x you can also use the querystring core module
const querystring = require('querystring');
app.get('/category', function(req, res) {
const query = querystring.stringify({
"a": 1,
"b": 2,
"valid":"your string here"
});
res.redirect('/?' + query);
});
Another way of doing it is by setting something up in the session. You can read how to set it up here, but to set and access variables is something like this:
app.get('/category', function(req, res) {
req.session.valid = true;
res.redirect('/');
});
And later on after the redirect...
app.get('/', function(req, res) {
var passedVariable = req.session.valid;
req.session.valid = null; // resets session variable
// Do something
});
There is also the option of using an old feature of Express, req.flash. Doing so in newer versions of Express will require you to use another library. Essentially it allows you to set up variables that will show up and reset the next time you go to a page. It's handy for showing errors to users, but again it's been removed by default. EDIT: Found a library that adds this functionality.
Hopefully that will give you a general idea how to pass information around in an Express application.
The easiest way I have found to pass data between routeHandlers to use next() no need to mess with redirect or sessions.
Optionally you could just call your homeCtrl(req,res) instead of next() and just pass the req and res
var express = require('express');
var jade = require('jade');
var http = require("http");
var app = express();
var server = http.createServer(app);
/////////////
// Routing //
/////////////
// Move route middleware into named
// functions
function homeCtrl(req, res) {
// Prepare the context
var context = req.dataProcessed;
res.render('home.jade', context);
}
function categoryCtrl(req, res, next) {
// Process the data received in req.body
// instead of res.redirect('/');
req.dataProcessed = somethingYouDid;
return next();
// optionally - Same effect
// accept no need to define homeCtrl
// as the last piece of middleware
// return homeCtrl(req, res, next);
}
app.get('/', homeCtrl);
app.post('/category', categoryCtrl, homeCtrl);
I had to find another solution because none of the provided solutions actually met my requirements, for the following reasons:
Query strings: You may not want to use query strings because the URLs could be shared by your users, and sometimes the query parameters do not make sense for a different user. For example, an error such as ?error=sessionExpired should never be displayed to another user by accident.
req.session: You may not want to use req.session because you need the express-session dependency for this, which includes setting up a session store (such as MongoDB), which you may not need at all, or maybe you are already using a custom session store solution.
next(): You may not want to use next() or next("router") because this essentially just renders your new page under the original URL, it's not really a redirect to the new URL, more like a forward/rewrite, which may not be acceptable.
So this is my fourth solution that doesn't suffer from any of the previous issues. Basically it involves using a temporary cookie, for which you will have to first install cookie-parser. Obviously this means it will only work where cookies are enabled, and with a limited amount of data.
Implementation example:
var cookieParser = require("cookie-parser");
app.use(cookieParser());
app.get("/", function(req, res) {
var context = req.cookies["context"];
res.clearCookie("context", { httpOnly: true });
res.render("home.jade", context); // Here context is just a string, you will have to provide a valid context for your template engine
});
app.post("/category", function(req, res) {
res.cookie("context", "myContext", { httpOnly: true });
res.redirect("/");
}
use app.set & app.get
Setting data
router.get(
"/facebook/callback",
passport.authenticate("facebook"),
(req, res) => {
req.app.set('user', res.req.user)
return res.redirect("/sign");
}
);
Getting data
router.get("/sign", (req, res) => {
console.log('sign', req.app.get('user'))
});
we can use express-session to send the required data
when you initialise the app
const express = require('express');
const app = express();
const session = require('express-session');
app.use(session({secret: 'mySecret', resave: false, saveUninitialized: false}));
so before redirection just save the context for the session
app.post('/category', function(req, res) {
// add your context here
req.session.context ='your context here' ;
res.redirect('/');
});
Now you can get the context anywhere for the session. it can get just by req.session.context
app.get('/', function(req, res) {
// So prepare the context
var context=req.session.context;
res.render('home.jade', context);
});
Here s what I suggest without using any other dependency , just node and express, use app.locals, here s an example :
app.get("/", function(req, res) {
var context = req.app.locals.specialContext;
req.app.locals.specialContext = null;
res.render("home.jade", context);
// or if you are using ejs
res.render("home", {context: context});
});
function middleware(req, res, next) {
req.app.locals.specialContext = * your context goes here *
res.redirect("/");
}
You can pass small bits of key/value pair data via the query string:
res.redirect('/?error=denied');
And javascript on the home page can access that and adjust its behavior accordingly.
Note that if you don't mind /category staying as the URL in the browser address bar, you can just render directly instead of redirecting. IMHO many times people use redirects because older web frameworks made directly responding difficult, but it's easy in express:
app.post('/category', function(req, res) {
// Process the data received in req.body
res.render('home.jade', {error: 'denied'});
});
As #Dropped.on.Caprica commented, using AJAX eliminates the URL changing concern.
Update 2021:
i tried url.format and querystring and both of them are deprecated, instead we can use URLSearchParams
const {URLSearchParams} = require('url')
app.get('/category', (req, res) =>{
const pathname = '/?'
const components ={
a:"a",
b:"b"
}
const urlParameters = new URLSearchParams(components)
res.redirect(pathname + urlParameters)
})
I use a very simple but efficient technique
in my app.js ( my entry point )
I define a variable like
let authUser = {};
Then I assign to it from my route page ( like after successful login )
authUser = matchedUser
It May be not the best approach but it fits my needs.
app.get('/category', function(req, res) {
var string = query
res.redirect('/?valid=' + string);
});
in the ejs you can directly use valid:
<% var k = valid %>
I have very simple node.js noob question. How do I pass a variable to an exported route function?
Routes file
exports.gettop = function(n, req, res) {
console.log(n);
res.send(200);
};
Server file
app.get('/api/v1/top100', routes.gettop(100));
Error: .get() requires callback functions but got a [object Undefined]
For your example, you want to create a new function that will close around your value of n. In your case, you are executing gettop and passing the returned value to express as your route, which means gettop needs to return the route handler.
exports.gettop = function(n){
return function(req, res) {
console.log(n);
res.send(200);
};
};
As your code looks like you're using express you can use express app locals and express result locals to pass variables to your route. While the other answers propose working solutions I think that it's less obtrusive to use express mechanisms to set these variables.
With response locals (See Express API reference) you first have to set a variable somewhere in a middleware or route. I'll show the middleware approach
app.use(function(req,res, next) {
res.locals.top = 200;
next();
});
then in your route you can access this property via res.locals.variablename
exports.gettop = function(req, res) {
console.log(res.locals.top);
res.send(200);
};
In case you want to make these settings application wide a better approach is to use app locals (See Express API reference)
To set an app locals variable you can use
app.locals.top = 100;
To access this variable from your route use
exports.gettop = function(req, res){
console.log(req.app.locals.top);
res.send(200);
};
As an alternative to loganfsmyth's (very valid!) solution, you could leave your gettop function as-is and create a partial function:
app.get('/api/v1/top100', routes.gettop.bind(null, 100));
Try
app.post('/find_user',
require('./naas/autentication'),
require('./naas/authorization')(paramForRouter),
require('./routes/users'));
Where
require('./naas/autentication') is for example
module.exports = function (req, res, next) {next();}
And require('./naas/authorization')(paramForRouter) is
module.exports = function (paramForRouter) {
return function (req, res, next) {
this.param = paramForRouter;
console.log("Param value",this.param);
next();
};
};
I'm using Passport.js to authenticate with Google via OAuth (I'm using the passport-google-oauth strategy). It works fine, but I'm currently redirecting the user to "/", and I'd like to send them to "/" plus the current hash tag. I can send the hash value in a query string parameter, but I can't seem to set that value to the callbackURL property of the object that I'm passing to authenticate.
Can someone provide an example or explanation as to the correct way to do this? I'm not beholden to using the query string, it just seemed the most straight-forward route, but I'm open to using a session variable or something else, if that would be easier or better practice.
Thank you.
You can achieve this effect by storing the return url in the session.
// server
var app, express;
express = require('express');
app = express();
app.configure(function() {
app.use(express.cookieSession({secret: 'shh'}));
});
app.get('/auth/twitter', function(req, res, next) {
// to return to '/#/returnHash', request this url:
// http://example.com/auth/twitter?return_url=%2F%23%2FreturnHash
// on the client you can get the hash value like this:
// encodeURIComponent("/"+window.location.hash)
req.session.return_url = req.query.return_url;
next();
}, passport.authenticate('twitter'));
app.get('/auth/twitter/callback', passport.authenticate('twitter', {
failureRedirect: '/login'
}), function(req, res) {
var url = req.session.return_url;
delete req.session.return_url;
// redirects to /#/returnHash
res.redirect(url);
});