Setup NodeJS with Apache ProxyPass on Raspberry Pi 2 and 3. This allows multiple NodeJS apps to run in the backend but under a single hostname/domain with different virtual subfolder path for each of them.
Referring to NodeJS guide on how to download, I followed the instructions on Debian-based linux distributions.
If you have installed NodeJS from the raspberrypi.org repository, I suggest that you purge them to get back to clean slate state:
sudo apt-get purge npm
sudo apt-get purge nodejs
You will need to install cURL if you do not have it:
sudo apt-get install -y curl
Next, run the following command to download and install NodeJS 8.x:
curl -sL https://deb.nodesource.com/setup_8.x | sudo -E bash -
sudo apt-get install -y nodejs
To find out the version installed:
node -v
Run a simple Hello World web server on NodeJS to verify that it works.
File: server.js
var http = require('http');
var port = 3000;
http.createServer(function (req, res) {
res.writeHead(200, { 'Content-Type': 'text/plain' });
res.end('Hello World\n');
}).listen(port, "localhost");
Run the app and return to console:
node server.js &
The Process ID (PID) will be shown. Take note of that ID, it will be different per run.
To verify, use cURL to query the node:
curl http://localhost:3000/
The output should be: Hello World
NodeJS runs on its own port as defined by the server.js script. Normally, we do not want this exposed to public. Instead, most would prefer to have http://<domain>/api/ instead of http://<domain>:3000/.
Assuming Apache 2.x is your web server, you could edit the virtual host config to proxy the requests on that path to your NodeJS instance.
Firstly, enable the Apache proxy_http module:
sudo a2enmod proxy
sudo a2enmod proxy_http
sudo service apache2 restart
Next, add the following lines into vhost config:
ProxyPreserveHost on
ProxyPass /api/ http://localhost:3000/
ProxyPassReverse /api/ http://localhost:3000/
For the vhost changes to take effect:
sudo service apache2 reload
To verify, use cURL to query the node again but this time via path on Apache web server:
curl http://localhost/api/
The output should be: Hello World