Akka gRPC

Support for building streaming gRPC servers and clients on top of Akka Streams.

This library is meant to be used as a building block in projects using the Akka toolkit.

The Akka family of projects is managed by teams at Lightbend with help from the community.

Documentation

Akka gRPC reference documentation

Project Status

This library is ready to be used in production

The API on both sides (Client and Server) is a simple Akka Streams-based one.

The client side is currently implemented on top of io.grpc:grpc-netty-shaded with an Akka HTTP client backend alternative available.

As for performance, we are currently relying on the JVM TLS implementation, which is sufficient for many use cases, but is planned to be replaced with conscrypt or netty-tcnative.

General overview

gRPC is a schema-first RPC framework, where your protocol is declared in a protobuf definition, and requests and responses will be streamed over an HTTP/2 connection.

Based on a protobuf service definition, akka-grpc can generate:

Model classes (using plain protoc for Java or scalapb for Scala)
The API (as an interface for Java or a trait for Scala), expressed in Akka Streams Sources
On the server side, code to create an Akka HTTP route based on your implementation of the API
On the client side, a client for the API.

Project structure

The project is split up in a number of subprojects:

codegen: code generation shared among plugins
runtime: run-time utilities used by the generated code
sbt-plugin: the sbt plugin
scalapb-protoc-plugin: the scalapb Scala model code generation packaged as a protoc plugin, to be used from gradle
interop-tests

Additionally, 'plugin-tester-java' and 'plugin-tester-scala' contain an example project in Java and Scala respectively, with both sbt and Gradle configurations.

License

Akka gRPC is licensed under the Business Source License 1.1, please see the Akka License FAQ.