Node.js is a free and open-source JavaScript platform that can be used to serve dynamic and responsive server-side content. It built on Chrome’s V8 JavaScript engine and able to executes JavaScript code outside of a web browser. It can be run on several operating systems including, Linux, FreeBSD, Windows, and macOS. Node.js also works on other web servers like Apache and Nginx.
In this tutorial, we will learn how to install and configure Node.js to handle backend requests and configure Nginx to handle front-end requests on Debian 10.
Prerequisites
- A server running Debian 10.
- A root password is configured on your server.
Getting Started
First, it is recommended to update your system to the latest version. You can do it with the following command:
apt-get update -y
apt-get upgrade -y
Once your server is updated, restart it to apply the changes.
Install Node.js
By default, the latest version of Node.js is not available in the Debian 10 default repository. So you will need to install it from the script.
First, install curl with the following command:
apt-get install curl -y
Next, download and install the Node.js installation script with the following command:
curl -sL https://deb.nodesource.com/setup_12.x | bash -
Once the installation has been completed, you can install the Node.js with the following command:
apt-get install nodejs -y
Once the installation has been completed successfully, you can verify the Node.js version with the following command:
nodejs --version
You should see the Node.js version in the following output:
v12.16.1
You can also check the NPM version by running the following command:
npm --version
You should see the NPM version in the following output:
6.13.4
Create Node.js Application
First, you will need to create a directory for your application. You can create it by running the following command:
mkdir nodeapp
Next, change the directory to nodeapp and install express with the following command:
cd nodeapp
npm install express
Next, create a sample Node.js application with express using the nano editor:
nano app.js
Add the following contents:
var express = require('express');
var app = express();
app.get('/', function(req, res){
res.send("Nginx as Frontend Server for Node.js!");
});
app.listen(8000, '127.0.0.1');
Save and close the file when you are finished.
Next, run your application with the following command:
node app.js
Next, open other terminal and verify the application with the following command:
netstat -antup | grep 8000
You should see that your Node.js application is listening on port 8000:
tcp 0 0 127.0.0.1:8000 0.0.0.0:* LISTEN 26193/node
You can also verify the application using curl command as shown below:
curl http://127.0.0.1:8000
If everything is fine, you should get the following output:
Nginx as Frontend Server for Node.js!
Install and Configure PM2
PM2 is a process manager to manage Node.js application. YOu can easily start, stop and enable Node.js application to start at boot using PM2.
First, install the latest version of PM2 using NPM as shown below:
npm install pm2 -g
Once installed, change the directory to nodeapp and your application with the following command:
cd nodeapp
pm2 start app.js
Once the application has been started, you should get the following output:
-------------
__/\\\\\\\\\\\\\____/\\\\____________/\\\\____/\\\\\\\\\_____
_\/\\\/////////\\\_\/\\\\\\________/\\\\\\__/\\\///////\\\___
_\/\\\_______\/\\\_\/\\\//\\\____/\\\//\\\_\///______\//\\\__
_\/\\\\\\\\\\\\\/__\/\\\\///\\\/\\\/_\/\\\___________/\\\/___
_\/\\\/////////____\/\\\__\///\\\/___\/\\\________/\\\//_____
_\/\\\_____________\/\\\____\///_____\/\\\_____/\\\//________
_\/\\\_____________\/\\\_____________\/\\\___/\\\/___________
_\/\\\_____________\/\\\_____________\/\\\__/\\\\\\\\\\\\\\\_
_\///______________\///______________\///__\///////////////__
Runtime Edition
PM2 is a Production Process Manager for Node.js applications
with a built-in Load Balancer.
Start and Daemonize any application:
$ pm2 start app.js
Load Balance 4 instances of api.js:
$ pm2 start api.js -i 4
Monitor in production:
$ pm2 monitor
Make pm2 auto-boot at server restart:
$ pm2 startup
To go further checkout:
http://pm2.io/
-------------
[PM2] Spawning PM2 daemon with pm2_home=/root/.pm2
[PM2] PM2 Successfully daemonized
[PM2] Starting /root/nodeapp/app.js in fork_mode (1 instance)
[PM2] Done.
?????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????
? id ? name ? namespace ? version ? mode ? pid ? uptime ? ? ? status ? cpu ? mem ? user ? watching ?
?????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????
? 0 ? app ? default ? N/A ? fork ? 13202 ? 0s ? 0 ? online ? 0% ? 27.2mb ? root ? disabled ?
?????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????
In the above output, you can see very useful information like, application PID, uptime, status, CPU and Memory usage.
Next, run the following command to create and configures a startup script for Node.js application so that your Node.js application will start automatically at boot.
pm2 startup
You should get the following output:
[PM2] Init System found: systemd Platform systemd Template [Unit] Description=PM2 process manager Documentation=https://pm2.keymetrics.io/ After=network.target [Service] Type=forking User=root LimitNOFILE=infinity LimitNPROC=infinity LimitCORE=infinity Environment=PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin Environment=PM2_HOME=/root/.pm2 PIDFile=/root/.pm2/pm2.pid Restart=on-failure ExecStart=/usr/lib/node_modules/pm2/bin/pm2 resurrect ExecReload=/usr/lib/node_modules/pm2/bin/pm2 reload all ExecStop=/usr/lib/node_modules/pm2/bin/pm2 kill [Install] WantedBy=multi-user.target Target path /etc/systemd/system/pm2-root.service Command list [ 'systemctl enable pm2-root' ] [PM2] Writing init configuration in /etc/systemd/system/pm2-root.service [PM2] Making script booting at startup... [PM2] [-] Executing: systemctl enable pm2-root... Created symlink /etc/systemd/system/multi-user.target.wants/pm2-root.service → /etc/systemd/system/pm2-root.service. [PM2] [v] Command successfully executed. +---------------------------------------+ [PM2] Freeze a process list on reboot via: $ pm2 save [PM2] Remove init script via: $ pm2 unstartup systemd
Next, start the PM2 service with the following command:
systemctl start pm2-root
Next, verify the status of PM2 service with the following command:
systemctl status pm2-root
You should get the following output:
? pm2-root.service - PM2 process manager
Loaded: loaded (/etc/systemd/system/pm2-root.service; enabled; vendor preset: enabled)
Active: active (running) since Thu 2020-03-26 06:04:28 UTC; 2s ago
Docs: https://pm2.keymetrics.io/
Process: 13387 ExecStart=/usr/lib/node_modules/pm2/bin/pm2 resurrect (code=exited, status=0/SUCCESS)
Main PID: 13191 (PM2 v4.2.3: God)
Tasks: 0 (limit: 4915)
CGroup: /system.slice/pm2-root.service
? 13191 PM2 v4.2.3: God Daemon (/root/.pm2)
Mar 26 06:04:28 kolab.linuxbuz.com pm2[13387]: [PM2] Restoring processes located in /root/.pm2/dump.pm2.bak
Mar 26 06:04:28 kolab.linuxbuz.com pm2[13387]: [PM2][ERROR] Failed to read dump file in /root/.pm2/dump.pm2.bak
Mar 26 06:04:28 kolab.linuxbuz.com pm2[13387]: [PM2][ERROR] No processes saved; DUMP file doesn't exist
Mar 26 06:04:28 kolab.linuxbuz.com pm2[13387]: ? PM2+ activated | Instance Name: node.myserver.tld-109e | Dash: https://app.pm2.io/#/r/7p66twg
Mar 26 06:04:28 kolab.linuxbuz.com pm2[13387]: ????????????????????????????????????????????????????????????????????????????????????????????????
Mar 26 06:04:28 kolab.linuxbuz.com pm2[13387]: ? id ? name ? namespace ? version ? mode ? pid ? uptime ? ? ? status ? cpu
Mar 26 06:04:28 kolab.linuxbuz.com pm2[13387]: ????????????????????????????????????????????????????????????????????????????????????????????????
Mar 26 06:04:28 kolab.linuxbuz.com pm2[13387]: ? 0 ? app ? default ? N/A ? fork ? 13202 ? 8m ? 0 ? online ? 0%
Mar 26 06:04:28 kolab.linuxbuz.com pm2[13387]: ????????????????????????????????????????????????????????????????????????????????????????????????
Mar 26 06:04:28 kolab.linuxbuz.com systemd[1]: Started PM2 process manager.
Configure Nginx as a Reverse Proxy for Node.js
At this point, your Node.js application is running and listening on the localhost. Next, you will need to configure Nginx as a front-end proxy server for Node.js application so that any user can access your application over the internet.
First, install the Nginx web server with the following command:
apt-get install nginx -y
Once installed, create an Nginx virtual host configuration file for Node.js application:
nano /etc/nginx/sites-enabled/myapp.conf
Add the following content:
server {
listen 80;
server_name node.myserver.tld;
location / {
proxy_pass http://127.0.0.1:8000;
proxy_http_version 1.1;
proxy_set_header Upgrade $http_upgrade;
proxy_set_header Connection 'upgrade';
proxy_set_header Host $host;
proxy_cache_bypass $http_upgrade;
}
}
Save and close the file when you are finished. Then, restart the Nginx server to apply the changes:
systemctl restart nginx
You can verify the status of Nginx service with the following command:
systemctl status nginx
You should see the following output:
? nginx.service - A high performance web server and a reverse proxy server
Loaded: loaded (/lib/systemd/system/nginx.service; enabled; vendor preset: enabled)
Active: active (running) since Tue 2020-03-25 12:42:49 UTC; 5min ago
Docs: man:nginx(8)
Process: 26180 ExecStartPre=/usr/sbin/nginx -t -q -g daemon on; master_process on; (code=exited, status=0/SUCCESS)
Process: 26182 ExecStart=/usr/sbin/nginx -g daemon on; master_process on; (code=exited, status=0/SUCCESS)
Main PID: 26183 (nginx)
Tasks: 3 (limit: 2359)
Memory: 5.5M
CGroup: /system.slice/nginx.service
??26183 nginx: master process /usr/sbin/nginx -g daemon on; master_process on;
??26184 nginx: worker process
??26185 nginx: worker process
Mar 25 12:42:49 debian10 systemd[1]: Starting A high performance web server and a reverse proxy server...
Mar 25 12:42:49 debian10 systemd[1]: Started A high performance web server and a reverse proxy server.
Once you are finished, you can proceed to the next step.
Access Your Node.js Application
At this point, Nginx is configured to serve your Node.js application.
Now, open your web browser and type the URL http://node.myserver.tld. You should see your Node.js application in the following screen:
Conclusion
In the above article, you learned how to set up Node.js application on Debian 10. You also learned how to run Node.js application as a daemon and configure Nginx as a reverse proxy to serve the application. I hope you can now easily host your Node.js application in a production environment.