Grails: Initialize variable using Configuration file - grails

Question

I just wanted to know that is it possible to set the value of a variable in Grails controller from the configuration file like config.groovy or some other configuration file?
For instance , my controller is as follows:
class WebsiteController {
def show(){
String user_name = "value to be fetched from configuration file"
}
}
Here, I want to set the value of user_name from the configuration file. I have no idea how to do this.
I have been given this requirement by my senior. I searched online but couldn't find anything relevant. If it is possible, please tell me the approach.
Thanks

Answer 1

Here is an example of properties added to the Config.groovy:
environments {
development {
tipline.email.address="joe#foo.us"
grails.logging.jul.usebridge = true
}
staging {
tipline.email.address="mailinglist#foo.us"
grails.logging.jul.usebridge = true
}
production {
tipline.email.address="mailinglist#foo.us"
grails.logging.jul.usebridge = false
// TODO: grails.serverURL = "http://www.changeme.com"
}
}
To access them in your code:
println("Email :"+grailsApplication.config.tipline.email.address)

Answer 2

Properties are properties =)
Properties properties = new Properties()
File propertiesFile = new File('test.properties')
propertiesFile.withInputStream {
properties.load(it)
}
def runtimeString = 'a'
assert properties."$runtimeString" == '1'
assert properties.b == '2'
Taken from Get values from properties file using Groovy

Answer 3

Another possibility is to inject parameters into the controller by using a property override configuration:
// Config.groovy:
website.user = "me"
beans {
'<replace by package>.WebsiteController' {
userName = website.user
}
}
// Controller:
class WebsiteController {
String userName
def show(){
//.. use userName ..
}
}
In this case you don't need grailsApplication and you don't hard code the configuration path in the Controller. Less dependencies make testing easier. :)