Awesome

sbt-avro

Overview

sbt-avro is a sbt plugin for generating Java sources for Avro schemas. It also supports referencing schemas from different files.

Usage

Installing the plugin

Add the plugin according to the sbt documentation.

For instance, add the following lines to project/plugins.sbt:

addSbtPlugin("com.github.sbt" % "sbt-avro" % "3.5.0")

Enable the plugin in your build.sbt and select the desired avro version to use:

enablePlugins(SbtAvro)
avroVersion := "1.12.0"

Config

An avro configuration will be added to the project. Libraries defined with this scope will be loaded by the sbt plugin to generate the avro classes.

Settings

Project settings

Name	Default	Description
`avroAdditionalDependencies`	`avro-compiler % avroVersion % "avro"`, `avro % avroVersion % "compile"`	Additional dependencies to be added to library dependencies.
`avroCompiler`	`com.github.sbt.avro.AvroCompilerBridge`	Sbt avro compiler class.
`avroCreateSetters`	`true`	Generate setters.
`avroEnableDecimalLogicalType`	`true`	Use `java.math.BigDecimal` instead of `java.nio.ByteBuffer` for logical type `decimal`.
`avroFieldVisibility`	`public`	Field visibility for the properties. Possible values: `private`, `public`.
`avroOptionalGetters`	`false` (requires avro `1.10+`)	Generate getters that return `Optional` for nullable fields.
`avroStringType`	`CharSequence`	Type for representing strings. Possible values: `CharSequence`, `String`, `Utf8`.
`avroUseNamespace`	`false`	Validate that directory layout reflects namespaces, i.e. `com/myorg/MyRecord.avsc`.
`avroVersion`	`1.12.0`	Avro version to use in the project.

Scoped settings (Compile/Test)

Name	Default	Description
`avroGenerate` / `target`	`sourceManaged` / `compiled_avro` / `$config`	Source directory for generated `.java` files.
`avroSource`	`sourceDirectory` / `$config` / `avro`	Default Avro source directory for `.avsc`, `.avdl` and `*.avpr` files.
`avroSpecificRecords`	`Seq.empty`	List of fully qualified Avro record class names to recompile with current avro version and settings.
`avroDependencyIncludeFilter`	`Compile`: `avro` classifier artifacts in `Avro` config<br>`Test`: nothing	Filter for including modules containing avro dependencies.
`avroUmanagedSourceDirectories`	`Seq(avroSource)`	Unmanaged Avro source directories, which contain manually created sources.
`avroUnpackDependencies` / `excludeFilter`	`HiddenFileFilter`	Filter for excluding avro specification files from unpacking.
`avroUnpackDependencies` / `includeFilter`	`AllPassFilter`	Filter for including avro specification files to unpack.
`avroUnpackDependencies` / `target`	`sourceManaged` / `avro` / `$config`	Target directory for schemas packaged in the dependencies
`packageAvro` / `artifactClassifier`	`Some("avro")`	Classifier for avro artifact
`packageAvro` / `publishArtifact`	`false`	Enable / Disable avro artifact publishing

Scoped Tasks (Compile/Test)

Name	Description
`avroGenerate`	Generate Java sources for Avro schemas. This task is automatically executed before `compile`.
`avroUnpackDependencies`	Unpack avro schemas from dependencies. This task is automatically executed before `avroGenerate`.
`packageAvro`	Produces an avro artifact, such as a jar containing avro schemas.

Examples

For example, to change the Java type of the string fields, add the following lines to build.sbt:

avroStringType := "String"

If you depend on an artifact with previously generated avro java classes with string fields as CharSequence, you can recompile them with String by also adding the following

Compile / avroSpecificRecords += "com.example.MyAvroRecord" // lib must be added in the avro scope

Packaging Avro files

Avro sources (*.avsc, *.avdl and *.avpr files) can be packaged in a separate jar with the source type and avro classifier by running packageAvro.

By default, sbt-avro does not publish this. You can enable it with

Compile / packageAvro / publishArtifact := true

Declaring dependencies

You can specify a dependency on an avro source artifact that contains the schemas like so:

libraryDependencies += "org" % "name" % "rev" % "avro" classifier "avro"

If some avro schemas are not packaged in a source/avro artifact, you can update the avroDependencyIncludeFilter setting to instruct the plugin to look for schemas in the desired dependency:

libraryDependencies += "org" % "name" % "rev" % "avro" // module containing avro schemas
Compile / avroDependencyIncludeFilter := configurationFilter("avro") && moduleFilter(organization = "org", name = "name")

If some artifact is meant to be used in the test scope only, you can do the following

libraryDependencies += "org" % "name" % "rev" % "avro" classifier "avro"
Compile / avroDependencyIncludeFilter ~= { old => old -- moduleFilter(organization = "org", name = "name") }
Test / avroDependencyIncludeFilter := configurationFilter("avro") && moduleFilter(organization = "org", name = "name")

License

This program is distributed under the BSD license. See the file LICENSE for more details.

Credits

sbt-avro is maintained by the sbt Community. The initial code was based on a similar plugin: sbt-protobuf. Feel free to file issues or pull requests.