marc0der / gradle-spawn-plugin

Gradle plugin for spawning and killing command line processes.

Gradle Spawn Plugin

This plugin is used for starting and stopping UNIX command line processes from within your build.

A typical application of this plugin is for stopping and starting an embedded web server when running functional tests from within your build.

Setup

Add the following to your build.gradle:

import com.wiredforcode.gradle.spawn.*

buildscript {
	repositories {
		...
		maven { url 'http://dl.bintray.com/vermeulen-mp/gradle-plugins' }
	}
	dependencies {
		classpath 'com.wiredforcode:gradle-spawn-plugin:0.8.0'
	}
}

apply plugin: 'com.wiredforcode.spawn'

task startServer(type: SpawnProcessTask, dependsOn: 'assemble') {
	command "java -jar ${projectDir}/build/libs/zim-service.jar"
	ready 'Started Application'
}

task stopServer(type: KillProcessTask)

The startServer task is used for starting the process.

The command line passed into the command method is typically a blocking process. The String passed into the ready method is the trigger used for continuing the build once the server process is up and running. If this String is discovered in the stdout stream of the server, the process will be placed into the background and the Gradle build will continue.

Once the build draws to a close, the stopServer task is then used to gracefully shut down the server process.

PID File

The SpawnProcessTask will automatically deposit a .pid.lock file in the working directory. This contains the PID of the running process. The KillProcessTask will read this lock file, kill the process gracefully, and remove the file.

It is also possible to set the name of the pid file allowing more than one process to be opened.

task startServer(type: SpawnProcessTask, dependsOn: 'assemble') {
	command "java -jar ${projectDir}/build/libs/zim-service.jar"
	ready 'Started Application'
	pidLockFileName '.other.pid.lock'
}