GrailsApplicationPidFileWriter and GrailsWebServerPortFileWriter are not active by default

[rainboyan]

In the grace-boot module, you can find two classes to create files that are often useful for process monitoring:

• GrailsApplicationPidFileWriter creates a file that contains the application PID (by default, in the application directory with a file name of grails.pid).
• GrailsWebServerPortFileWriter creates a file (or files) that contain the ports of the running web server (by default, in the application directory with a file name of grails.port).

By default, these writers are not activated, but you can enable them:

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

org.springframework.context.ApplicationListener=\
org.grails.boot.context.GrailsApplicationPidFileWriter,\
org.grails.boot.context.web.GrailsWebServerPortFileWriter