How to write a properties file using WriteProperties Gradle API? - gradle

Question

I am trying to write some key-value pairs to a properties file in a gradle task. I looked up that Gradle provides an api WriteProperties for that, but I was unable to use it.
I tried different approaches (I am learning Gradle, so I don't know if I used some incorrect syntax):
1.
task myTask {
doLast {
WriteProperties {
outputFile = file 'prop.properties'
encoding = 'UTF-8'
properties = [TEST:42]
}
}
}
task myTask {
doLast {
def writer by register(WriteProperties.class) {
outputFile = file 'prop.properties'
encoding = 'UTF-8'
properties = [TEST:42]
}
}
}
task myTask {
doLast {
// Other stuff
}
}
task writeProperty(type: WriteProperties) {
outputFile = file 'prop.properties'
encoding = 'UTF-8'
properties = [TEST:42]
}
writeProperty.dependsOn myTask
task myTask {
doLast {
// Other stuff
}
finalizedBy writeProperty
}
task writeProperty(type: WriteProperties) {
outputFile = file 'prop.properties'
encoding = 'UTF-8'
properties = [TEST:42]
}
task myTask {
doLast {
// Other stuff
}
}
class MyPlugin implements Plugin<Project>{
void apply(Project project) {
project.task('writeProperty') {
WriteProperties {
outputFile = file 'prop.properties'
encoding = 'UTF-8'
properties = [TEST:42]
}
}
}
}
apply plugin: MyPlugin
writeProperty.dependsOn myTask
None of them created a file with the values. Is there some other way to do it? I wanted to know the proper way of using the WriteProperties api, since the documentation did now have any helpful examples.
I found solutions with java syntax to create Properties() object and writing to file, but none with this api.

Answer 1

I'm creating a property file like so, using pure Gradle/Groovy:
file "$buildDir/prop.properties" write [ TEST:42 ].collect{ k, v -> "$k=$v" }.join( '\n' )
OR
file "$buildDir/prop.properties" withWriter{ out ->
[ TEST:42 ].each{ k, v -> out << k << '=' << v << '\n' }
}