%PDF-
%PDF-
Mini Shell
Mini Shell
/*!
* express-flash-notification
* Copyright(c) 2015-2017 Carlos Ascari Gutierrez Hermosillo
* MIT License
*/
const { format, isArray } = require('util');
const async = require('async');
/**
* Default value used when calling the `req.flash` method withouth specifying
* the redirect argument.
* @property REDIRECT
* @type {Boolean|String}
* @final
*/
const REDIRECT = true;
/**
* Default middleware options
* @type {Object}
* @private
*/
const DEFAULT_OPTIONS = {
sessionName: 'flash',
utilityName: 'flash',
localsName: 'flash',
viewName: 'flash',
beforeSingleRender: function(item, callback) {
callback(null, item);
},
afterAllRender: function(htmlFragments, callback) {
callback(null, htmlFragments.join('\n'));
},
};
/**
* Utility used to check whether an argument is a Native Object
* @return {Boolean}
* @private
*/
const isObject = (sample) => sample && typeof sample === 'object' && !isArray(sample);
/**
* Function used to expose express instance and configuration options.
* The actual middleware is returned.
* @param {Express} app
* @param {Object} options
*/
function Module (app, options=DEFAULT_OPTIONS) {
const sessionName = options.sessionName || options.session_name || DEFAULT_OPTIONS.sessionName;
const utilityName = options.utilityName || options.utility_name || DEFAULT_OPTIONS.utilityName;
const localsName = options.localsName || options.locals_name || DEFAULT_OPTIONS.localsName;
const viewName = options.viewName || options.view_name || DEFAULT_OPTIONS.viewName;
const beforeSingleRender = options.beforeSingleRender || options.beforeSingleRender || DEFAULT_OPTIONS.beforeSingleRender;
const afterAllRender = options.afterAllRender || options.afterAllRender || DEFAULT_OPTIONS.afterAllRender;
/**
* Render notifications in queue.
* @private
*/
function render(req, res, next) {
if (!req.session[sessionName].length) {
next();
} else {
const resultHTML = [];
async.each(
req.session[sessionName],
function(item, next) {
beforeSingleRender(item, function(error, item) {
if (error) return next(error);
app.render(viewName, item, function(error, html) {
if (error) return next(error);
resultHTML.push(html);
next(null);
})
})
},
function(error) {
if (error) return next(error);
req.session[sessionName].length = 0;
afterAllRender(resultHTML, function(error, html) {
if (error) return next(error);
res.locals[localsName] = html;
next();
})
}
)
}
}
/**
* Adds flash method to req object and renders all notifications found in
* req.session
* @param {ReadStream} req
* @param {WriteStream} res
* @param {Function} next
*/
function FlashMiddleware(req, res, next) {
if (!isObject(req.session)) throw new Error('express-session is required. (npm i express-session)');
if (!req.session[sessionName] || !isArray(req.session[sessionName])) req.session[sessionName] = [];
/**
* Utility used to programmatically add flash notifications
* @method Flash Utility
*/
req[utilityName] = function() {
const argc = arguments.length;
let notification;
let redirect = REDIRECT;
// Parse arguments
if (argc) {
if (argc === 1) {
const arg = arguments[0];
if (isObject(arg)) {
notification = arg;
redirect = (arg.redirect === undefined) ? redirect : arg.redirect;
} else {
notification = {
message: '' + arg
};
}
} else {
notification = {
type: '' + arguments[0],
message: '' + arguments[1]
};
redirect = (arguments[2] === undefined) ? redirect : arguments[2];
}
}
// Queue Notification
if (notification && req.session[sessionName]) {
req.session[sessionName].push(notification);
}
// If redirect is set, refresh or redirect, accordingly. Otherwise, render the
// notifications now since it's on this request where they will be displayed.
if (redirect) {
const redirectUrl = (typeof redirect === 'string') ? redirect : req.originalUrl;
res.redirect(redirectUrl);
} else {
/**
* When there is no redirect, notifications must be rendered now and since
* rendering is async (and this method is sync), a *promise* like function is returned.
* The function can be called with a callback that will be called after all notifcations
* are rendered, otherwise, rendering will be done during the next request.
*/
return function ManualRender(callback) {
render(req, res, callback);
}
}
}
/**
* Process Queued Notifications
*/
render(req, res, next);
}
return FlashMiddleware;
}
module.exports = Module;
Zerion Mini Shell 1.0