Gradle plugin that loads org.springframework.boot into projects

Question

I'm writing a custom gradle plugin Foo and I want to load the org.springframework.boot plugin into projects that apply the Foo plugin. I can load various other plugins this way, but this particular plugin doesn't want to behave the same way.

Foo build.gradle

buildscript {
    ext {
        springBootVersion = "2.1.3.RELEASE"
    }
}

apply plugin: "groovy"

repositories {
    maven { url "http://custom.repo/blah" }
}

dependencies {
    implementation gradleApi()
    implementation localGroovy()

    implementation("org.springframework.boot:spring-boot-gradle-plugin:${springBootVersion}")
}

Foo plugin

class BuildPlugin implements Plugin<Project> {

    @Override
    void apply(Project project) {
        project.repositories {
            maven { url "http://custom.repo/blah" }
        }

        project.plugins.apply("org.springframework.boot")
    }
}

Project build.gradle

buildscript {
    dependencies {
        classpath files("/some/cool/path/foo-plugin.jar")
    }
}

apply plugin: "com.whatever.foo-id"

Project build output

$ ./gradlew --stacktrace clean build

FAILURE: Build failed with an exception.

* Where:
Build file '/cool/project/location/bar/build.gradle' line: 40

* What went wrong:
A problem occurred evaluating root project 'bar'.
> Failed to apply plugin [id 'com.whatever.foo-id']
   > Plugin with id 'org.springframework.boot' not found.

Is it possible to apply a plugin 1 from plugin 2 where plugin 1 is a classpath dependency?

Answer 1

This isn't possible. The classpath is what pulls in the plugins, so it is impossible for them to modify the thing before they are pulled in.