grails.util.Environment, defines a number of preconfigured environments
When runni
If you create a custom environment, you can use it anywhere that the environments {} block is used. For example, in addition to Bootstrap.groovy and Config.groovy, you can also use it in DataSource.groovy and even other Config files like Searchable.groovy.
Also, I believe
Environment.currentEnvironment.name will return 'pre_production' in your case.