How to use plugin-subproject in another subproject?

Help/Discuss
1

I have similar project structure:

-root
    -sub-lib
    -sub-gradle-plugin
    -sub-demo-app

sub-gradle-plugin is a binary plugin. And I want it to use in demo-app project for testing/developing. So, as for now I’m used to publish plugin to local maven repo and thus have this in setting file to be able to fetch plugin from sub-demo-app:

pluginManagement {
    repositories {
        gradlePluginPortal()
        maven("maven-local")
    }
}

Each time I make a change into plugin, I have to publish it first to local folder, and only then it updates in demo-app. But, can I link this plugin to demo-app-project like I do, for example for library sub-lib project ? That is use direct dependency to a gradle project.

dependencies {
     implementation(project(":sub-lib"))
}
2

You need to use a composite build to do this.

See

3

So, in your example gradle-plugin isn’t a part of the same root project. it’s a separate project that doesn’t share common configuration. and doc says:
must not have a rootProject.name the same as another included build.

4

So, in your example gradle-plugin isn’t a part of the same root project.

Correct, there’s two root project’s but they act like a single project thanks to Gradle’s Composite Build feature

5

I’ve been thinking that the point around Composite Build is that we could link to exactly separate project as would it be our own subproject. is it just another workaround here ?

6

Using a locally built gradle plugin in your build is different from using one java project in another. There’s a chicken or egg problem where the buildscript classloader needs to be defined before the plugin is built.

For this reason, you need a separate root project for the plugin which is built before the client project’s buildscript classloader is defined.

Luckily, the composite build feature makes it behave as if its a multi module build for the most part.

1 Like
7

Oh, yes. Thank you, I got the point. I’ll try this way. But Composite Build seems aren’t supposed to share common config, yes ?

subprojects {
apply(plugin = "org.jetbrains.kotlin.jvm")

repositories {
    jcenter()
}

dependencies {
    "implementation"(platform("org.jetbrains.kotlin:kotlin-bom"))
    "implementation"("org.jetbrains.kotlin:kotlin-stdlib-jdk8")
}

tasks {
    withType<KotlinCompile> {
        kotlinOptions.apiVersion = "1.3"
        kotlinOptions.languageVersion = "1.3"
        kotlinOptions.jvmTarget = "1.8"
    }
}
8

You could use a commom.gradle which you apply in both. See my version.txt logic where I share the version number between the two builds

9

One thing I forgot to ask is this: Do you intend to publish this plugin for use in multiple projects? Or do you only need it inside a single (multi module?) project?

If you don’t intend to publish the plugin, you can simply put the plugin code in the “buildSrc” project

10

Yes, I intend. At least, I want to try :smile:
Eventually I came to decision not to use composite build (as for now). It complicates config-sharing and, additionally, gradle-plugin-subproject has two direct dependencies on its co-projects. It would be simpler to keep them together.

dependencies {
    runtimeOnly(project(":launcher-app"))
    implementation(project(":manifest-lib"))
}

And now I’m wondering if it’s possible to include these two in gradle plugin publication that java-gradle-plugin creates for publishing in order not to publish them separately.