How do I redirect in expressjs while passing some context

Question

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.

Answer 1

Hello @kartik,

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);

// 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);

Hope this is helpful!!

Thank you!!