-- EDIT --
I wrote some middlware to do this: https://npmjs.org/package/flashify
So since the release of Express 3.0, the changes have removed req.flash()
https://github.com/visionmedia/express/wiki/Migrating-from-2.x-to-3.x (source)
So here is my question now. They have advised to use req.session.messages in a local to display a flash.
So to make a session accessible to the view, we have to do the following:
nb: In coffee-script
app.locals.use (req,res) ->
res.locals.session = req.session
How would we access the session data from the view then clear it? We can't clear the contents of session after the view has rendered, but we can't clear it because it wont reach the view so im a bit lost as to how one would get around this problem?
You can use the connect-flash middleware to add the req.flash() functionality back into express 3.0.
I believe they simply moved req.flash to req.session.messages
From Tim's link above:
This middleware was extracted from Express 2.x, after Express 3.x removed direct support for the flash. connect-flash brings this functionality back to Express 3.x, as well as any other middleware-compatible framework or application. +1 for radical reusability.
Express 2.x migrate to 3.x page says the following:
req.flash() (just use sessions: req.session.messages = ['foo'] or similar)Besides connect-flash and express-flash, there's also just flash, which is made by the expressjs team (which I consider as a bonus). Super simple to use:
npm i flash
app.use(session()); // session middleware
app.use(require('flash')());
app.use(function (req, res) {
// flash a message
req.flash('info', 'hello!');
next();
})
while message = flash.shift() // consume messages as jade reads them
a.alert(class='alert-' + message.type)
p= message.message
Note how the code above shifts them; if you just read the array, the flash messages keep hanging there in the session (which is great for redirects).
Install connect-flash middleware, require it, then
app.use(flash()) and note it should be appear before app.use(express.session...)