Incrementing Grails application version during WAR packaging

Grails comes with several predefined properties, which can be used in application or build process. One of them is application version. It can be found in application.properties file and the usual way is to change it manually. Of course we can find a plugin – version updater – that makes that via Grails console. But what about situation in which every WAR creation should trigger version update?

Quick fix for that can be seen below (it is based on the script I have found on this blog). It is a simple script which should be places in /scripts folder of our project in a file named _Events.groovy. During WAR creation this script will be read and executed. Of course logic presented is fairly simple and lacks some parameters validation but I will leave it up to the developer.

eventCreateWarStart = { warName, stagingDir ->
	
	Map<String,Integer> mappings = [ 'M' : 0, 'm' : 1, 'p' : 2 ]
	String versionParam = System.getProperty('version.update.position', 'M')
	def lastAppVersionNumberList = metadata.'app.version'.split('\\.')
			   
	
	println "*** Started customised version update of Grails app. Current version: ${metadata.'app.version'}"
				
	lastAppVersionNumberList[ mappings[versionParam] ] =        Integer.valueOf(lastAppVersionNumberList[mappings[versionParam]]) + 1
	
	metadata.'app.version' = lastAppVersionNumberList.join('.')
	metadata.persist() 
	
	println "*** Ended customised version update of Grails app. Current version: ${lastAppVersionNumberList.join('.')}"
}