This module contains Protobuf definitions for external and inter-service communication in Salus Telemetry. The built library includes the Java classes generated from those definitions.

This repository also supplies a Go library for using the Salus Telemetry protocols, which can be added as a dependency using:

go get -u github.com/racker/salus-telemetry-protocol

Generating Java source from Avro/Protobuf schemas

Some of the data model types are generated from Avro and Protobuf schemas located in

• src/main/avro
• src/main/proto

The Java source code is generated during a normal Maven build; however, the specific phase generate-sources can be used to only perform the code generation:

mvn generate-sources

Any regular Maven phases, like compile, package, or install will also work since they pass through the generate-sources phase, as seen here.

Generating Go source

NOTE unlike Java code generation, the generated Go source code must be source controlled. This is due to Go's ability to reference a git repository as the library/module rather than requiring a separately built and deployed artifact.

One-time setup

Install Go 1.13 or newer.

Install protoc by using one of the following options:

• Follow the instructions in the quickstart guide
• On Mac OS you can use brew install protobuf
• On Windows you can use scoop install protobuf where Scoop is available here
• On Debian based Linux systems you can use apt-get install protobuf-compiler

Download the modules required by the generated code by invoking

go mod download

Install the grpc plugin for protoc by invoking

make install-grpc-plugin

Make sure $GOPATH/bin is in your $PATH. If you don't have $GOPATH declared, reference $HOME/go/bin instead.

Re-generating source code

When changes are made to the proto files, re-generate the *.pb.go files using:

make generate

Don't forget to git add and commit the re-generated files

Performing a release

While on the latest commit of master ensure there are no local changes and run the following.

mvn release:clean release:prepare

Notes

When choosing the next snapshot version, use the X.Y-SNAPSHOT form where Y "rounds up" from the released X.Y.Z. For example, when releasing 0.1.1 specify 0.2-SNAPSHOT as the next snapshot. You would again specifiy 0.2-SNAPSHOT if later releasing a bug fix 0.1.2.