WIP: AVRO-4223 Gradle plugin for generating Java code

[frevib]

What is the purpose of the change

Gradle plugin to generate Java code from Avro files

Verifying this change

This change added tests and can be verified as follows:

cd to avro/lang/java/gradle-plugin

./gradlew test

Documentation

• Does this pull request introduce a new feature? (yes)
• If yes, how is the feature documented? (docs): https://github.com/frevib/avro/blob/AVRO-4223-gradle-plugin/lang/java/gradle-plugin/README.md

Release

https://plugins.gradle.org/plugin/eu.eventloopsoftware.avro-gradle-plugin

0.0.2 is released and fully works with AVSC files:

0.0.5

0.0.8

0.1.0 this release adds Protocol support.

0.1.1 Fix issue with Gradle multi project, where sources would not appear on the classpath

Installation instructions: https://github.com/frevib/avro/blob/AVRO-4223-gradle-plugin/lang/java/gradle-plugin/README.md#version

An official release will be done in the coming month

[frevib]

Avro gradle plugin 0.1.0 is released: https://plugins.gradle.org/plugin/eu.eventloopsoftware.avro-gradle-plugin

Protocol support has been added in this release

[frevib]

@raphaelauv did you test the latest release https://plugins.gradle.org/plugin/eu.eventloopsoftware.avro-gradle-plugin? No need to add compileJava.source(avroGenerateJavaClasses) any more.

[opwvhk]

This is yet another marked improvement. Thank you!

I have a few open comments, and we'll want to fix the build, but otherwise I'm happy with the result.

[martin-g]

I have created https://issues.apache.org/jira/browse/INFRA-27616 for the requirement from Gradle to prove the ownership of avro.apache.org DNS domain.

[martin-g]

Why this uses the current class' loader ?
loadLogicalTypesFactories() and doCompile() use the thread's class loader

[frevib]

I've used the same as in the Maven plugin:

avro/lang/java/maven-plugin/src/main/java/org/apache/avro/mojo/AbstractAvroMojo.java

Line 391 in 4e37673

Class<?> klass = Class.forName(velocityToolClassName);

and:

avro/lang/java/maven-plugin/src/main/java/org/apache/avro/mojo/AbstractAvroMojo.java

Line 462 in 4e37673

protected URLClassLoader createClassLoader() throws DependencyResolutionRequiredException, MalformedURLException {

[martin-g]

Same here - testExcludes

[frevib]

We're not making a distinction between main and test includes/excludes like in the Maven plugin. If you compile for the test classpath, the same value is used from includedSchemaFiles, excludedSchemaFiles, includedProtocolFiles and excludedProtocolFiles.

It's a bit of design choice, but I thought it's a bit unnecessary to have this distinction. Thoughts?

[martin-g]

We use deploy to deploy -SNAPSHOTs for the Maven artefacts.
AFAIK Gradle plugins repo does not allow -SNAPSHOTs

[frevib]

Correct, the Gradle plugin portal does not support snapshots. It works different than Sonatype, where you first push and later release via the Sonatype UI. With the Gradle publish plugin when you run ./gradlew publishPlugins you'll immediately publish the plugin to the portal.

You can however publish -SNAPSHOT to the local Maven repo with ./gradlew publishToMavenLocal