Using sbt Avrohugger plugin in gradle - scala

Question

I am using https://github.com/julianpeeters/avrohugger sbt plugin to generate Scala case classes for Avro .avsc files. How can I use the same plugin in a Gradle project?

Answer 1

I created gradle plugin for generating Scala case classes from Avro schema and it internally uses avrohugger library.
So now it's enough to add this plugin to your project:
plugins {
id 'com.zlad.gradle.avrohugger' version '0.2.1'
}
When you want to compile Scala sources you need Scala library dependency too:
plugins {
id 'scala'
id 'com.zlad.gradle.avrohugger' version '0.2.1'
}
repositories {
mavenCentral()
}
dependencies {
compile 'org.scala-lang:scala-library:2.12.8'
}
Scala classes will be automatically generated during build before compileScala task. By default avro schema should be in src/main/avro and generated sources will be in build/generated-src/avro
You can call generateAvroScala to invoke Scala sources generation manually.
You can find all details and configuration options on gradle-avrohugger-plugin github page.

Answer 2

I ended up using the avrohugger-tools library in Gradle to autogenerate Scala case classes whenever my schemas were updated. Your mileage may vary, but this finally worked for me:
build.gradle.kts
import java.io.File
plugins {
scala
id("com.github.maiflai.scalatest") version "0.19"
}
version = "1.0"
configurations {
register("avrohugger-tools")
}
dependencies {
// Scala std-libs
implementation(Dependencies.Libs.Scala.library)
// AvroHugger tools JAR
"avrohugger-tools"("com.julianpeeters:avrohugger-tools_2.12:1.0.0-RC14")
// testing
testImplementation(gradleTestKit())
testImplementation("junit:junit:4.12")
testImplementation("org.scalatest:scalatest_2.12:3.0.5")
testRuntime("org.pegdown:pegdown:1.4.2")
}
fun normalizeFileSeparator(path: String) = path.replace('/', File.separatorChar)
val genAvro = task<JavaExec>("genAvro") {
val sourceAvroPath = normalizeFileSeparator("src/main/avro/")
val sourceAvroFiles = fileTree(mapOf(
"dir" to sourceAvroPath, "include" to listOf("**/*.avsc")
))
val targetPath = normalizeFileSeparator("src/gen/")
doFirst {
delete(targetPath)
}
classpath = configurations["avrohugger-tools"]
main = "avrohugger.tool.Main"
args(
"generate", "schema",
sourceAvroFiles.files.joinToString(separator=" "),
targetPath
)
inputs.files(sourceAvroFiles)
outputs.files(targetPath)
}
the<JavaPluginConvention>().sourceSets.getByName(
SourceSet.MAIN_SOURCE_SET_NAME
).java.srcDir("gen")
tasks.withType<ScalaCompile> {
dependsOn(genAvro)
}
inline fun <reified T : Task> TaskContainer.existing() = existing(T::class)
inline fun <reified T : Task> TaskContainer.register(name: String, configuration: Action<in T>) = register(name, T::class, configuration)
Note that I'm also building/test a Scala source tree in this package, so some of the Scala-specific pieces can be presumably elided.
Really hope this helps!