55. Process monitoring

In Spring Boot Actuator you can find a couple of classes to create files that are useful for process monitoring:

  • ApplicationPidFileWriter creates a file containing the application PID (by default in the application directory with the file name application.pid ).

  • EmbeddedServerPortFileWriter creates a file (or files) containing the ports of the embedded server (by default in the application directory with the file name application.port ).

These writers are not activated by default, but you can enable them in one of the ways described below.

55.1 Extend configuration

In META-INF/spring.factories file you can activate the listener(s) that writes a PID file. Example:

org.springframework.context.ApplicationListener=\
org.springframework.boot.system.ApplicationPidFileWriter,\
org.springframework.boot.actuate.system.EmbeddedServerPortFileWriter

55.2 Programmatically

You can also activate a listener by invoking the SpringApplication.addListeners(…) method and passing the appropriate Writer object. This method also allows you to customize the file name and path via the Writer constructor.