![\"\"](\"http:\/\/www.maginobi.net\/main\/wp-content\/uploads\/2021\/01\/cpanel_setup_njs.jpg\")
<\/figure>\n\n\n\n![\"\"](\"http:\/\/www.maginobi.net\/main\/wp-content\/uploads\/2021\/01\/cpanel_njs_fields-1024x428.jpg\")
<\/figure>\n\n\n\n- The Application Root tells the server where your application code is stored.<\/li>
- The Application Url determines what public url your application will be accessible from; more information below.<\/li>
- The Application Startup File is the name of the entry point Javascript file for your application. This is the same ‘main’ file referenced in your package.json file if you have one.<\/li><\/ul>\n\n\n\n
Click the “Run NPM Install” button to install your application’s dependencies. Then you can click the “Start App” button.<\/p>\n\n\n\n
The Application Url<\/h4>\n\n\n\n
The application url that you specify during application setup does not by itself determine what urls you can access your application from. All that the application url specified during setup does is create the appropriate path in your public html directory and adds a .htaccess file at that path, which directs any http requests to that path over to your application. If your application does not have logic based on the request path, this will allow your application to be accessed at the url you specified. For example, something like the following code snippet from cPanel’s Node.js setup example<\/a> would work great.<\/p>\n\n\n\n
const http = require('http');<\/code>\nconst hostname = '127.0.0.1';<\/code>\nconst port = 3000;<\/code>\n<\/code>\nconst server = http.createServer((req, res) => {<\/code>\nres.statusCode = 200;<\/code>\nres.setHeader('Content-Type', 'text\/plain');<\/code>\nres.end('Hello World! NodeJS \\n');<\/code>\n});<\/code>\n<\/code>\nserver.listen(port, hostname, () => {<\/code>\nconsole.log(`Server running at http:\/\/${hostname}:${port}\/`);<\/code>\n});<\/code><\/pre>\n\n\n\nHowever, many (most) applications provide multiple services at different paths with some routing logic based on the request path. For these applications, Phusion Passenger does not clip the base application url from the request before passing the request to your application, nor does it pass the base application url to Node.js through an environment variable or some other means. So, if your application uses routing like in the following code snippet with express, it will not work:<\/p>\n\n\n\n
const express = require('express');<\/code>\nconst hostname = '127.0.0.1';<\/code>\nconst port = 3000;<\/code>\n<\/code>\nconst app = express();<\/code>\n<\/code>\napp.get('\/hello', (req, res) => {<\/code>\nres.send('Hello Route! Express NodeJS');<\/code>\n});<\/code>\n<\/code>\napp.listen(port, hostname, () => {<\/code>\nconsole.log(`Server running at http:\/\/${hostname}:${port}\/`);<\/code>\n});<\/code><\/pre>\n\n\n\nThis can be fixed by adding a BASE_URL environment variable to pass in the configured application url (more on adding environment variables below) and stripping that string off the request url before the rest of your routing takes place.<\/p>\n\n\n\n
const base_url = process.env.BASE_URL || '';<\/code>\n<\/code>\nconst app = express();<\/code>\nconst someRoute = express.Router();<\/code>\n\/\/ Set up someRoute...<\/code>\n<\/code>\napp.use(base_url, someRoute);<\/code><\/pre>\n\n\n\nWith our hello world example, that would give us…<\/p>\n\n\n\n
const base_url = process.env.BASE_URL || '';<\/code>\nconst express = require('express');<\/code>\nconst hostname = '127.0.0.1';<\/code>\nconst port = 3000;<\/code>\n<\/code>\nconst app = express();<\/code>\nconst route = express.Route();<\/code>\n<\/code>\nroute.get('\/hello', (req, res) => {<\/code>\nres.send('Hello Route! Express NodeJS');<\/code>\n});<\/code>\n<\/code>\napp.use(base_url, route);<\/code>\napp.listen(port, hostname, () => {<\/code>\nconsole.log(`Server running at http:\/\/${hostname}:${port}${base_url}\/`);<\/code>\n});<\/code><\/pre>\n\n\n\nEnvironment Variables<\/h4>\n\n\n\n
cPanel allows you to set the environment variables under which your application will be run using the application setup interface. These environment variables can be accessed from within the Node.js code as properties of process.env. The following images show an example setup for a BASE_URL environment variable.<\/p>\n\n\n\n
![\"\"](\"http:\/\/www.maginobi.net\/main\/wp-content\/uploads\/2021\/01\/cpanel_add_env_var-1024x132.jpg\")
<\/figure>\n\n\n\n![\"\"](\"http:\/\/www.maginobi.net\/main\/wp-content\/uploads\/2021\/01\/cpanel_base_url_var-1024x147.jpg\")
<\/figure>\n\n\n\nA special environment variable here is the NODE_ENV application mode variable. It will always be one of the lowercase strings ‘development’ or ‘production’ and it is controlled separately from other environment variables by using the “Application mode” dropdown at the top of the setup menu.<\/p>\n\n\n\n
Red Herrings<\/h4>\n\n\n\n
Some other websites offering tips about Node.js and cPanel point to port and .htaccess configuration as possible causes of issues that you might have setting up a Node.js app, but these are red herrings.<\/p>\n\n\n\n