Protobuf Golang

Setup

See Protobuf Basics

Create a new go module to work in:

go mod init github.com/hoani/robot
go get google.golang.org/protobuf/proto

Protobuf message

// robot.proto
syntax = "proto3";
option go_package = "github.com/hoani/robot";

package robot;

message ServoState {
  double angle = 1;
}

message GimbalState {
  ServoState servoPitch = 1;
  ServoState servoYaw = 2;
}

Compile

protoc --go_out=proto --go_opt=paths=source_relative robot.proto

Encoding and Decoding

// main.go
package main

import (
	"fmt"

	robot "github.com/hoani/robot/proto"
	"google.golang.org/protobuf/proto"
)

func main() {
	g := &robot.GimbalState{
		ServoPitch: &robot.ServoState{Angle: 10.0},
		ServoYaw:   &robot.ServoState{Angle: -15.5},
	}
	fmt.Printf("Gimbal  \tPitch: %v \tYaw: %v\n",
		g.ServoPitch.Angle,
		g.ServoYaw.Angle)

	encoded, _ := proto.Marshal(g)
	fmt.Printf("Encoded \tBytes: %v\n", len(encoded))

	decoded := &robot.GimbalState{}
	proto.Unmarshal(encoded, decoded)

	fmt.Printf("Decoded \tPitch: %v \tYaw: %v\n",
		decoded.ServoPitch.Angle,
		decoded.ServoYaw.Angle)
}

Running the example:

└─ $ ▶ go run ./main.go
Gimbal          Pitch: 10       Yaw: -15.5
Encoded         Bytes: 22
Decoded         Pitch: 10       Yaw: -15.5