session-flash

The flash is a special area of the session used for storing messages. Messages are written to the flash and cleared after being displayed to the user. The flash is typically used in combination with redirects, ensuring that the message is available to the next page that is to be rendered.

Install

npm i session-flash

Usage

Express 5.x

Flash messages are stored in the session. First, setup sessions as usual by enabling cookieParser and session middleware. Then, use flash middleware provided by session-flash.

const app = express();
const cookieParser = require('cookie-parser');
const session = require('express-session');
const flash = require('session-flash');

app.use(cookieParser());

app.use(session({
  secret: 'session-secret',
  resave: false,
  saveUninitialized: false,
  cookie: { maxAge: 60000 }
}));

app.use(flash());

With the flash middleware in place, all requests will have a req.flash() function that can be used for flash messages.

app.get('/flash', function(req, res){
  // Set a flash message by passing the key, followed by the value, to req.flash().
  req.flash('info', 'Flash is back!')
  res.redirect('/');
});

app.get('/', function(req, res){
  // Get an array of flash messages by passing the key to req.flash()
  res.render('index', { messages: req.flash('info') });
});

License

[The MIT License]

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