Node.js is a popular server-side development language with powerful backend functions. During the development process, we often need to watch the program running in the background so that we can debug and fix it in time when errors occur. This article will introduce how to implement this function in the Node.js backend.
What is watching the running status of the program in the background
Watching the running status of the program in the background refers to outputting the running status of the program in text form on the terminal or command line interface when the program is running. This makes it easy to view the program's process, status, and log information, and detect errors in a timely manner.
How to check the running status of the program in the Node.js background
In Node.js, we can use the console.log()
method to output information to the console. When running in the background, you can output in the following two ways:
1. Use the &
method
When running the Node.js program, you can use it at the end of the command The &
symbols place the program in the background. While the program is running in the background, you can view its operation at any time.
node app.js &
2. Use the pm2
management tool
pm2
is a popular Node.js process management tool. It can monitor the running status of the program and supports functions such as log management and error monitoring. Use pm2
to manage Node.js programs to run, debug and manage programs in the background.
2.1 Installationpm2
You can install pm2
through npm:
npm install pm2 -g
2.2 Start the program
Use pm2
When starting the Node.js program, log information can be output to the console and log files at the same time to facilitate viewing of the running status.
pm2 start app.js --name myapp
2.3 Check the running status
Use pm2
To view the running status and log information of the program, you can use the following command:
pm2 list // 查看程序列表 pm2 show <app_name> // 查看程序状态 pm2 logs // 输出所有程序的日志信息 pm2 logs <app_name> // 输出指定程序的日志信息</app_name></app_name>
Summary
Through the above two methods, you can easily watch the program running status in the background in Node.js. Using pm2
management tools can make program management and debugging more convenient and improve development efficiency.
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