I'm writing a Gradle plugin which contains a collection of multiple chunks of independent configuration which will be applied to any project applying the plugin.
I want to keep the fragments very separate to discourage other people from adding unrelated logic to an existing place, and to improve visibility of what the plugin is actually configuring.
So I thought I could do this:
class CommonChecksPlugin implements Plugin<Project> {
#Override
void apply(Project project) {
project.apply plugin: 'base'
def resolveFile = { filename ->
new URL(buildscript.sourceURI.toURL(), filename)
}
project.apply from: resolveFile('configuration1.gradle')
project.apply from: resolveFile('configuration2.gradle')
}
}
Example configurationN.gradle:
task 'checkSomething', type: CheckSomething
Problem is, this Java class CheckSomething cannot be resolved.
Is there a sensible way to do this other than just giving up and moving all the sub-scripts in as full Groovy classes? I'm reluctant to move them to classes, because I want to apply the same checks to the plugin project itself, and it seems difficult to apply them if they require compilation.
The applied script has a different classloader to the plugin, it doesn't inherit the buildscript classloader so therefore the task isn't on the classpath. You can do the following:
project.ext.CheckSomething = CheckSomething
project.apply from: resolveFile('configuration1.gradle')
See https://discuss.gradle.org/t/buildscript-configurations-classpath-not-available-in-apply-from-scripts/1391
Related
How to add a dependency constraint to a project from a custom gradle plugin?
I want to create a gradle plugin that will constrain transitive dependencies in the project the plugin is applied to. Ideally, I want this plugin to follow the following rules:
Only try and apply a constraint to a project if the it exists in the project. E.g. only apply a constraint on dependency X if dependency X is pulled into the project.
Apply the constraints automatically on application of the plugin, I don't want to create/run an extra task or anything like that.
(Bonus) Don't apply the constraints to primary dependencies, only transitive dependencies.
Here's what I have so far.
class ConstraintPlugin implements Plugin<Project> {
private Map<String, String> constraintMap = [
"jackson-core": "2.13.2",
"logback-classic": "2.3.9"
]
#Override
void apply(Project project) {
project.configurations.each {config ->
config.resolvedConfiguration.resolvedArtifacts.each {dep ->
if (constraintMap.containsKey(dep.name)) {
ModuleVersionIdentifier id = dep.moduleVersion.id
String constraintVersion = constraintMap.get(id.name)
DependencyConstraint dc = new DefaultDependencyConstraint(id.group, id.name, constraintVersion)
config.dependencyConstraints.add(dc)
}
}
}
I'm using a map instantiated within the constraint plugin class with the names of the dependencies I want to constrain along with the versions to constrain to in the project this plugin is applied to. Here I want to constrain the jackson-core and logback-classic dependencies.
My first thought was to run through each configuration and see if that dependency name is present within that configuration. If so, create a new DependencyConstraint and add it to the configuration. However this is not working when I apply the plugin to another project.
Also note I am not disregarding primary dependencies quite yet, this feature is more like a "nice to have" at this point, I haven't figured out how to only look at transitive dependencies within a given configuration.
I think my issue lies with how I am applying the new DependencyConstraint programmatically but I can't seem to find a way to add a constraint that works. The only other way I've tried is project.dependencies.constraints.create(dc) which also doesn't work.
The title basically says it all.
I am trying to create a plugin that can be configured and depending on the configuration, the task provided by the plugin adds compileOnly or implementation deppendencies to the project.
The resources on writing custom Gradle plugins are abhorrent (especially in Kotlin instead of Groovy) and I can't figure out how to do this myself.
This is where I'm at with my custom plugin code:
class SpigotVersioner: Plugin<Project> {
override fun apply(project: Project) {
println("Latest spigot version: ${WebScraper.getLatestVersion()}")
val extension = project.extensions.create("spigot", SpigotExtension::class.java)
extension.apiVersion.set("latest")
extension.bukkitVersion.set("latest")
project.task("compileSpigotAPI") {
it.group = "spigot"
it.description = "Adds the spigot api implementation to the project."
it.doLast {
val apiVersion = extension.apiVersion.get()
val dependency = deriveDependencyStr(apiVersion)
//DOESN'T WORK!
project.dependencies {
compileOnly(dependency)
}
//WHAT ARE THESE PARAMETERS SUPPOSED TO BE?
project.dependencies.add(configurationName: String, dependencyNotation: Any)
}
}
}
}
This is supposed to mimic something like
dependencies {
compileOnly 'my.derived.dependency.str:apiVersion:xy'
}
only the dependency being added is supposed to be configurable via an extension.
If possible, I'd like to extend this to also add the appropriate repository as well but the dependency issue is more important.
Bit of an old question now, but I too struggled with this so hopefully this answer is of use to someone.
//WHAT ARE THESE PARAMETERS SUPPOSED TO BE?
project.dependencies.add(configurationName: String, dependencyNotation: Any)
The configurationName is the configuration that you wish to add the dependency to e.g. implementation, testImplementation or api etc.
The dependencyNotation can be any of the following:
String Notation: Simply a String written using Gradle dependency notation e.g. com.mycompany:my-awesome-dependency:1.2.3. There are ways to also specify things like strictness when using these 'simple' declarations, this is somewhat documented here.
Map Notation: This is where you pass a Map<String, String> containing key-value pairs representing the dependency. The documentation on this is either non existent or elusive, but for example: "group": "com.mycompany", "name": "my-awesome-dependency", "version": "1.2.3".
Dependency Interface: This is where you pass in an object that implements one of the Dependency interfaces that the Gradle API provides. The most basic being org.gradle.api.artifacts.Dependency. The main issue with this method is again that the documentation is either elusive or non-existent. I cannot see a way to have Gradle create one of these objects (or see any pre implemented classes in the public API). You could always just implement the interface but there are some methods on there like contentEquals and copy() which seem overkill to implement.
My recommendation if it suits your use case would be to use the first option above.
I'm using the Kotlin MPP plugin (with .kts support) and while I've been reading some code I came upon build.gradle.kts files like this:
kotlin {
sourceSets {
commonMain {
dependencies {
api(kotlinxCollectionsImmutable)
}
}
}
dependencies {
with(Libs) {
commonMainApi(kotlinStdLibCommon)
commonMainApi(kotlinxCoroutinesCommon)
}
}
}
What is the difference between declaring an api dependency within a sourceSet compared to declaring a commonMainApi dependency? Is there any?
No difference. The commonMainApi is just an alternative way of doing the same, and doesn't look to be recommended any more. Link - https://kotlinlang.ru/docs/reference/building-mpp-with-gradle.html
Альтернативным способом указания зависимостей является использование
встроенного DSL Gradle на верхнем уровне с именами конфигурации,
следующими за шаблоном : [translation:
Alternatively, dependencies can be declared by specifying
configuration names at the top level using the built-in Gradle DSL]
dependencies {
commonMainApi 'com.example:foo-common:1.0'
jvm6MainApi 'com.example:foo-jvm6:1.0'
}
Interestingly, this document is described as a translation of https://kotlinlang.org/docs/reference/building-mpp-with-gradle.html where this paragraph (about the alternative syntax) is completely missing, so one can only deduce that the English version has been updated and the alternative syntax removed as either not recommended or obsolete at this point.
I’ve written a custom task in Kotlin and located it inside buildSrc as recommended. The custom task calls javaexec. Something like this:
private fun custom() {
project.javaexec {
main = "com.thirdParty.something.Main"
classpath = ???
args("...")
}
}
Two questions:
Is project.javaexec the best way to call a main method from within a custom task?
How can I configure classpath such that com.thirdParty.something.Main remains a dependency of the custom task (i.e. buildSrc/build.kotlin.kts), and not the main project?
A gradle build has several submodules. Some of them have the java plugin applied, some don't. I'm trying to configure the plugin only when it's applied. To do this, I add the following in my top-level build.gradle file:
allprojects {
plugins.withType(JavaPlugin) {
//some configuration on the JavaPlugin
}
}
However, I also noticed the following style:
allprojects {
plugins.withType(JavaPlugin).whenPluginAdded {
//some configuration on the JavaPlugin
}
}
What's the difference between the 2. When do I use the withType(){}-style configuration and when do I use the withType().whenPluginAdded{}-style?
When you use whenPluginAdded() it invokes whenObjectAdded() on the current collection. And when you call withType() and pass a Closure, it invokes all() on the current collection, which in its turn calls whenObjectAdded() on a copied collection.
So both these methods do the same thing but the former makes a defensive copy of a plugin collection.