How to run a node.js app as a background service ?

Node. js is a platform built on Chrome’s JavaScript v8 engine, which is used for easily building fast and scalable network applications, javascript uses an event-driven, non-blocking I/O model that makes it lightweight and efficient which is perfect for data-intensive real-time applications that run across distributed devices and to make use of the tools (or packages) in Node. js, we need to be able to install in our machine and manage them in a useful way.

To run a node.js app as a background service is to even after closing the node terminal, the app server needs to be kept running.

Methods to run node.js app as background service:

Method 1: The easiest method to make a node.js app run as a background service is to use the forever tool. The forever is a simple Command Line Interface Tool that ensures that a given particular script runs continuously without any interaction.

Command for Installation: The following command installs the forever tool in the app.

$ npm install forever -g

Example of Installation of forever

Command to Start forever: To start the forever tool, run the following commands replacing <app_name> with the name of the node.js app.

$ forever start /<app_name>/index.js

Example of Starting forever

Method 2: The second method involves create a service file and manually starting the app and enabling the service to keep it running in the background.

• Step 1: Create a new file <app_name>.service file replacing <app_name> with the name of the node.js app. Inside the files, enter the following values:

  ExecStart=/var/www/<app_name>/app.js
  Restart=always
  User=nobody
  Group=nogroup
  Environment=PATH=/usr/bin:/usr/local/bin
  Environment=NODE_ENV=production
  WorkingDirectory=/var/www/<app_name>

• Step 2: After configuring the service file,

  Copy the <app_name>.service file into the /etc/systemd/system.

• Step3: Start the app with the following command to make it run with the service file:

  systemctl start <app_name>

Method 3: Another method which can be used to run a node.js app as a background by using nohup. The nohup is another Command Line Interface Tool which can be used to run a node.js app as a background service.

Run the following command to start the nohup replacing the <app_name> with the name of the node.js app:

$ nohup node /<app_name>/index.js &

The nohup command does not terminate this process even then the command terminal is closed.

Example of using nohup