SBT Settings

Basic Installation

To automatically generate Scala case classes for your messages add ScalaPBā€™s sbt plugin to your project. Create a file named project/plugins.sbt containing the following line (or add the following lines if a file with this name already exists):

addSbtPlugin("com.thesamet" % "sbt-protoc" % "0.99.28")

libraryDependencies += "com.thesamet.scalapb" %% "compilerplugin" % "0.10.1"

Add the following line to your build.sbt:

PB.targets in Compile := Seq(
  scalapb.gen() -> (sourceManaged in Compile).value
)

Running the compile command in sbt will generate Scala sources from your protos and compile them. If you just want to generate Scala sources for your protocol buffers without compiling them, run protoc-generate.

Additionally, if you need customizations from scalapb/scalapb.proto or anything from google/protobuf/*.proto, add the following to your build.sbt:

libraryDependencies += "com.thesamet.scalapb" %% "scalapb-runtime" % scalapb.compiler.Version.scalapbVersion % "protobuf"

Defaults

The plugin assumes your proto files are under src/main/protobuf, however this is configurable using the PB.protoSources in Compile setting.

By default, sbt-protoc invokes protoc 3.x that is shipped with protoc-jar. If you would like to run a different version of protoc:

PB.protocVersion := "-v3.11.4"

See all available options in sbt-protoc documentation

Java Conversions

To enable Java conversions add the following to your build.sbt:

PB.targets in Compile := Seq(
  PB.gens.java -> (sourceManaged in Compile).value,
  scalapb.gen(javaConversions=true) -> (sourceManaged in Compile).value
)

gRPC

Generating gRPC stubs for services is enabled by default. To disable:

PB.targets in Compile := Seq(
  scalapb.gen(grpc=false) -> (sourceManaged in Compile).value
)

Additional options to the generator

scalapb.gen(
  flatPackage: Boolean = false,
  javaConversions: Boolean = false,
  grpc: Boolean = true,
  singleLineToProtoString: Boolean = false,
  asciiFormatToString: Boolean = false,
  lenses: Boolean = true,
  retainSourceCodeInfo: Boolean = false
)
Option scalapbc Description
flatPackage flat_package When set, ScalaPB will not append the protofile base name to the package name.
javaConversions java_conversions Generates in the companion object two functions, toJavaProto and fromJavaProto that convert between the Scala case class and the Java protobufs. For the generated code to compile, the Java protobuf code need to be also generated or available as a library dependency.
grpc grpc Generates gRPC code for services. Default is true in scalapb.gen, and need to be explicitly specified in scalapbc.
singleLineToProtoString single_line_to_proto_string By default, ScalaPB generates a toProtoString() method that renders the message as a multi-line format (using TextFormat.printToUnicodeString). If set, ScalaPB generates toString() methods that use the single line format.
asciiFormatToString ascii_format_to_string Setting this to true, overrides toString to return a standard ASCII representation of the message by calling toProtoString.
lenses no_lenses By default, ScalaPB generates lenses for each message for easy updating. If you are not using this feature and would like to reduce code size or compilation time, you can set this to false and lenses will not be generated.
retainSourceCodeInfo retain_source_code_info Retain source code information (locations, comments) provided by protoc in the descriptors. Use the location accessor to get that information from a descriptor.