Inside my index.ejs (standard html file):
<% include taskList %>
My taskList.ejs tries to access a variable (tasks) which is delivered from the controller:
exports.taskList = function(req, res) {
res.render('taskList', {
tasks: tasks
});
}
This doesn't seem to be possible when including the taskList as the include doesn't call the controller -> tasks is undefined.
Any solution to this?
Related
I have an express app, in which I have the following code:
app.get('*', (req, res) => {
res.send('404', {
title: 404,
name: 'James Olaleye',
errorMessage: 'Page not found',
});
});
However, My IDE is warning about this message:
express deprecated res.send(status, body): Use
res.status(status).send(body) instead
And with the above code, My Browser is returning the following payload as a JSON object:
{
"title": 404,
"name": "James Olaleye",
"errorMessage": "Page not found"
}
What I want, is to display a 404 Not found page to the user, how can this be achived?
You have two seperate problem
1: you are using an old way to response to the request insted use this res.status(STATUS_CODE).send(BODY)
2: you are sending a json yet you want to display a 404 page in this case you need to send a html template
so your code should look like this
app.get('*', (req, res) => {
res.status(404).send("<div>404 Not Found</div>");
});
I updated your question a bit to make it clearer for future references.
the method res.send is deprecated, among other things because it's usages is too ambiguous. A server response, can be a lot of things, it can be a page, it can be a file, and it can be a simple JSON object (which you have here).
In your case, when you run res.send(404,{ /*...*/ }), the express app assumes you want to send a JSON object, so it does just that.
There are multiple possible ways, to achieve what you want, but I will stick to the most simple solution.
If you want to display an HTML page, in the most simplest form, you can actually just change your piece of code to do this instead:
app.status(404).send(`<h1>Page not found</h1>`)
This will essentially, show a page, instead of a JSON object.
You can even define the whole HTML file if you like:
app.status(404).send(
`
<html>
<!DOCTYPE html>
<head>
<title>404</title>
</head>
<body>
<h1>James Olaleye</h1>
<h1>Page Not Found</h1>
</body>
</html>
`
)
This would be the fastest way to achieve what you want.
A step further, would be to create an HTML file some where in your app, and to send the HTML file instead.
If your source code looks like this:
/
src/
index.js
htmls/
404.html
<!-- htmls/404.html -->
<html>
<!DOCTYPE html>
<head>
<title>404</title>
</head>
<body>
<h1>James Olaleye</h1>
<h1>Page Not Found</h1>
</body>
</html>
// src/index.js
const express = require('express');
const app = express();
const path = require('path');
const PORT = 3000;
app.get('/', function(req, res) {
const options = {
root: path.join(__dirname, '..', 'htmls')
};
res.sendFile('404.html', options, function (err) {
if (err) {
next(err);
} else {
console.log('Sent:', fileName);
}
});
});
This would allow you to have multiple HTML files which you can send around.
There are like I stated, other options as well, but that would make this answer way too long and out of scope. If you are interested, you can research Using template engines with Express and start with the following link.
Happy coding :)
I am new in ExpressJS, I know how to pass data from backend to the an ejs page, but I wanted to know how to pass data to a js file in the public folder?
So to pass data to a js file ( which js file is in the same folder as ejs ) while rendering the ejs page in the same time .
From ExpressJS I pass data to ejs by rendering ejs page like this
exports.user_signup = (req, res, next) => {
res.render('login', { page:'Login', email: req.body.email, idd: user[0]._id,} );
}
The ejs file :
<script src="file1.js"></script>
<%= email %>
So what I want, is to pass some data from ExpressJS to file1.js (which is in public folder)..
You cant access ejs data in a Javascript file or pass in data to a js file.
One possible way, Is that you can make use of variable passed to an ejs file.
Copy in your JS code to your ejs file and enclose them in a <script> tag.
pass in your required data to the ejs file ( in our case index.ejs ).
res.render('index', {data: 'some data'});
Inside the <script> tag in ejs file you can access the data like.
<script>
var x= <%- data %>;
console.log(x);
</script>
I'm working on a Node.js/Express that uses EJS and trying to render certain views on desktop or mobile.
I've added the following middleware to return the user agent in my app.js:
app.use(function(req, res, next) {
res.locals.ua = req.get('User-Agent');
next();
});
Next, if I echo <%= ua %> in my view, I successfully get the user agent, but I'm not sure how to actually check specific agents.
I tried <$ if(ua.match(/iPhone)) { %> as a quick example, but got a syntax error. Any help would be appreciated!
Several errors:
1) You started with a $ inside your embedded script. You should instead use a %.
2) You need to close out your regex with a /.
Something like this:
<% if(ua.match(/Intel/)) { %>
<%= ua %>
<% } %>
I'm creating my frist AngularJS application.
I have a kind of problem with my Index page.
There can be two different templates depending if User is authenticated or not.
My idea is to have a MainController defined before ng-view and a view controller (indexController, aboutController, ...) depending which view is displayed.
I've made a service UserService which mission is to get user's data from my server and serve them to controllers.
The problem is I want my MainController to get the user's data.
I've read things about resolve and promise but it only works with view controllers because it's defined in $routeProvider.
My question is how can I initialize my MainController data before executing my app routes ?
PS : A bit of code to help
index.html
<div id="page" ng-controller="MainController as Main">
<div id="navbar-container" class="shadow1">
<navbar></navbar>
</div>
<div class="row">
<div id="page-container" class="large-12 columns">
<div ng-view></div>
</div>
</div>
</div>
mainController.js
...
define([], function()
{
return angular.module('MyApp.controllers', []).controller('MainController', ['$scope', '$http', 'UserService', function($scope, $http, UserService)
{
// I want this to be defined before executing the app //
$scope.currentUser = UserService.getCurrentUser();
}]);
});
...
userService.js
define(['angular'], function (angular)
{
return angular.module('MyApp.services', []).service('UserService', ['$http', function($http)
{
var _currentUser = null;
var _promise = (_currentUser !== null) ? _currentUser : $http.get('/api/user').success(function(data)
{
_currentUser = data.result;
});
return {
promise : _promise,
getCurrentUser : function()
{
return _currentUser;
},
isAuthenticated : function()
{
return (_currentUser !== null);
},
};
}
]);
});
Maybe there is another way to do what I expect but i'm really a noob with AngularJS. I really would appreciate some help.
Thank you in advance.
I think you have to write $scope.currentUser = UserService.getCurrentUser(); line in run() method of angular js which is first fire when application load
Actually Config blocks run before run blocks. This is only relevant if you are trying to resolve in ng-route or ui-router.
Configuration blocks - get executed during the provider registrations and configuration
phase. Only providers and constants can be injected into configuration blocks. This is to
prevent accidental instantiation of services before they have been fully configured.
Run blocks - get executed after the injector is created and are used to kickstart the
application. Only instances and constants can be injected into run blocks. This is to prevent
further system configuration during application run time.
Line 122
Ok, so I have built a blog using Jekyll and you can define variables in a file _config.yml which are accessible in all of the templates/layouts. I am currently using Node.JS / Express with EJS templates and ejs-locals (for partials/layouts. I am looking to do something similar to the global variables like site.title that are found in _config.yml if anyone is familiar with Jekyll. I have variables like the site's title, (rather than page title), author/company name, which stay the same on all of my pages.
Here is an example of what I am currently doing.:
exports.index = function(req, res){
res.render('index', {
siteTitle: 'My Website Title',
pageTitle: 'The Root Splash Page',
author: 'Cory Gross',
description: 'My app description',
indexSpecificData: someData
});
};
exports.home = function (req, res) {
res.render('home', {
siteTitle: 'My Website Title',
pageTitle: 'The Home Page',
author: 'Cory Gross',
description: 'My app description',
homeSpecificData: someOtherData
});
};
I would like to be able to define variables like my site's title, description, author, etc in one place and have them accessible in my layouts/templates through EJS without having to pass them as options to each call to res.render. Is there a way to do this and still allow me to pass in other variables specific to each page?
After having a chance to study the Express 3 API Reference a bit more I discovered what I was looking for. Specifically the entries for app.locals and then a bit farther down res.locals held the answers I needed.
I discovered for myself that the function app.locals takes an object and stores all of its properties as global variables scoped to the application. These globals are passed as local variables to each view. The function res.locals, however, is scoped to the request and thus, response local variables are accessible only to the view(s) rendered during that particular request/response.
So for my case in my app.js what I did was add:
app.locals({
site: {
title: 'ExpressBootstrapEJS',
description: 'A boilerplate for a simple web application with a Node.JS and Express backend, with an EJS template with using Twitter Bootstrap.'
},
author: {
name: 'Cory Gross',
contact: 'CoryG89#gmail.com'
}
});
Then all of these variables are accessible in my views as site.title, site.description, author.name, author.contact.
I could also define local variables for each response to a request with res.locals, or simply pass variables like the page's title in as the optionsparameter in the render call.
EDIT: This method will not allow you to use these locals in your middleware. I actually did run into this as Pickels suggests in the comment below. In this case you will need to create a middleware function as such in his alternative (and appreciated) answer. Your middleware function will need to add them to res.locals for each response and then call next. This middleware function will need to be placed above any other middleware which needs to use these locals.
EDIT: Another difference between declaring locals via app.locals and res.locals is that with app.locals the variables are set a single time and persist throughout the life of the application. When you set locals with res.locals in your middleware, these are set everytime you get a request. You should basically prefer setting globals via app.locals unless the value depends on the request req variable passed into the middleware. If the value doesn't change then it will be more efficient for it to be set just once in app.locals.
You can do this by adding them to the locals object in a general middleware.
app.use(function (req, res, next) {
res.locals = {
siteTitle: "My Website's Title",
pageTitle: "The Home Page",
author: "Cory Gross",
description: "My app's description",
};
next();
});
Locals is also a function which will extend the locals object rather than overwriting it. So the following works as well
res.locals({
siteTitle: "My Website's Title",
pageTitle: "The Home Page",
author: "Cory Gross",
description: "My app's description",
});
Full example
var app = express();
var middleware = {
render: function (view) {
return function (req, res, next) {
res.render(view);
}
},
globalLocals: function (req, res, next) {
res.locals({
siteTitle: "My Website's Title",
pageTitle: "The Root Splash Page",
author: "Cory Gross",
description: "My app's description",
});
next();
},
index: function (req, res, next) {
res.locals({
indexSpecificData: someData
});
next();
}
};
app.use(middleware.globalLocals);
app.get('/', middleware.index, middleware.render('home'));
app.get('/products', middleware.products, middleware.render('products'));
I also added a generic render middleware. This way you don't have to add res.render to each route which means you have better code reuse. Once you go down the reusable middleware route you'll notice you will have lots of building blocks which will speed up development tremendously.
For Express 4.0 I found that using application level variables works a little differently & Cory's answer did not work for me.
From the docs: http://expressjs.com/en/api.html#app.locals
I found that you could declare a global variable for the app in
app.locals
e.g
app.locals.baseUrl = "http://www.google.com"
And then in your application you can access these variables & in your express middleware you can access them in the req object as
req.app.locals.baseUrl
e.g.
console.log(req.app.locals.baseUrl)
//prints out http://www.google.com
In your app.js you need add something like this
global.myvar = 100;
Now, in all your files you want use this variable, you can just access it as myvar
One way to do this by updating the app.locals variable for that app in app.js
Set via following
var app = express();
app.locals.appName = "DRC on FHIR";
Get / Access
app.listen(3000, function () {
console.log('[' + app.locals.appName + '] => app listening on port 3001!');
});
Elaborating with a screenshot from #RamRovi example with slight enhancement.
you can also use "global"
Example:
declare like this :
app.use(function(req,res,next){
global.site_url = req.headers.host; // hostname = 'localhost:8080'
next();
});
Use like this:
in any views or ejs file
<%
console.log(site_url);
%>
in js files
console.log(site_url);
With the differents answers, I implemented this code to use an external file JSON loaded in "app.locals"
Parameters
{
"web": {
"title" : "Le titre de ma Page",
"cssFile" : "20200608_1018.css"
}
}
Application
var express = require('express');
var appli = express();
var serveur = require('http').Server(appli);
var myParams = require('./include/my_params.json');
var myFonctions = require('./include/my_fonctions.js');
appli.locals = myParams;
EJS Page
<!DOCTYPE html>
<html lang="fr">
<head>
<meta charset="UTF-8">
<title><%= web.title %></title>
<link rel="stylesheet" type="text/css" href="/css/<%= web.cssFile %>">
</head>
</body>
</html>
Hoping it will help
What I do in order to avoid having a polluted global scope is to create a script that I can include anywhere.
// my-script.js
const ActionsOverTime = require('#bigteam/node-aot').ActionsOverTime;
const config = require('../../config/config').actionsOverTime;
let aotInstance;
(function () {
if (!aotInstance) {
console.log('Create new aot instance');
aotInstance = ActionsOverTime.createActionOverTimeEmitter(config);
}
})();
exports = aotInstance;
Doing this will only create a new instance once and share that everywhere where the file is included. I am not sure if it is because the variable is cached or of it because of an internal reference mechanism for the application (that might include caching). Any comments on how node resolves this would be great.
Maybe also read this to get the gist on how require works:
http://fredkschott.com/post/2014/06/require-and-the-module-system/