A simple ExpressJS flash middleware

This middleware adds a dead simple flash method to the request object and makes it also available inside your templates.

npm i simple-express-flash --save

import express from 'express';
import session from 'express-session';
import flash from 'simple-express-flash';

express()
  .use(session({
    resave: false,
    saveUninitialized: false,
    secret: 'my keyboard cat was replaced by a dog'
  }))
  .use(flash);

app.use(function (req) {
  /**
   * Store a message
   * @param {string} key
   * @param {string} message
   * @returns {string[]} a collection of set messages
   */
  req.flash('key', 'message text');
   
  /**
   * Retrieve an array of messages by key, removing them from storage
   * (such is the nature of flash messages, they disappear in a "flash")
   * @param {string} key
   * @returns {string[]}
   */
  req.flash('key');
   
  /**
   * Retrieve all messages
   * @example
   * // returns {key: ['message text']}
   * @returns {Object}
   */
  req.flash();
});

The exact same function can be used inside of your templates

each message in flash('error')
  .alert.alert-danger(role='alert')= message