protoc --go_out=plugins=grpc:example example.proto

에러

protoc --go_out=plugins=grpc:example example.proto                 
protoc-gen-go: unable to determine Go import path for "example.proto"

Please specify either:
        • a "go_package" option in the .proto source file, or
        • a "M" argument on the command line.

See https://protobuf.dev/reference/go/go-generated#package for more information.

해결방법

proto파일에 option을 주고 해결했다.

syntax = "proto3";

option go_package="./example";

package example;

message Message {
    string body = 1;
}

service exampleService {
    rpc Hello(Message) returns (Message);
}