Question

Within a custom gradle plugin the project.version seems to always be unspecified. Why and how to retrieve the project.version within a custom plugin (class)?

For Example:

apply plugin: 'java'
apply plugin: MyPlugin

version = "1.0.0"

println "In build file: $project.version" 

class MyPlugin implements Plugin<Project> {
  public void apply(Project project) {
    project.task('myTask') {
      println "In plugin: $project.version"
    }
  }
}

Prints out:

%> gradle -q myTask
  In plugin: unspecified
  In build file: 1.0.0

Besides the how I really would like to know the why?

Answer 1

You set the property after you call apply

If you move

version = "1.0.0"

To before the line

apply plugin: MyPlugin

It should work

Edit

Following Peter’s answer, you can see that this works also:

apply plugin: 'java'
apply plugin: MyPlugin

version = "1.0.0"

println "In build file: $project.version" 

class MyPlugin implements Plugin<Project> {
  public void apply(Project project) {
    project.task('myTask') {
      project.gradle.projectsEvaluated { 
        println "In plugin: $project.version"
      }
    }
  }
}

To delay the evaluation of $project.version until evaluation of the build is complete