Convert protobuf to struct in golang

I want to convert the proto Message to struct. Definitions of proto Message and struct:

ProtoMessage:
message Person {
  string Name = 1;
  int64 Age = 2;
  string Location = 3;
}

Human Struct:
type human struct {
	Name     string `protobuf:"Name"`
	Age      int64  `protobuf:"Age"`
	Location string `protobuf:"Location"`
}

Right now I see that the only option is to convert proto to JSON and JSON to struct using protojson and json library. Can someone recommend any other way of conversion?

The protobuf compiler should effectively do this for you.

From scratch, do this prep (the 75705541 number is this present stackoverflow question):

$ mkdir 75705541
$ cd 75705541
$ wget https://github.com/protocolbuffers/protobuf/releases/download/v22.2/protoc-22.2-linux-x86_64.zip
$ unzip protoc-22.2-linux-x86_64.zip
$ PATH="$(pwd)/bin:${PATH}"
$ go install google.golang.org/protobuf/cmd/protoc-gen-go@latest

Create a local file (ex.proto):

syntax = "proto3";

message Person {
  string Name = 1;
  int64 Age = 2;
  string Location = 3;
}

Then compile it to Go:

$ protoc -I=./ --go_out=./ --go_opt=Mex.proto=this/ex ex.proto

The generated output, this/ex/ex.pb.go contains this definition for Person:

type Person struct {
        state         protoimpl.MessageState
        sizeCache     protoimpl.SizeCache
        unknownFields protoimpl.UnknownFields

        Name     string `protobuf:"bytes,1,opt,name=Name,proto3" json:"Name,omitempty"`
        Age      int64  `protobuf:"varint,2,opt,name=Age,proto3" json:"Age,omitempty"`
        Location string `protobuf:"bytes,3,opt,name=Location,proto3" json:"Location,omitempty"`
}

which is almost what you want. It has some extra fields, but these are private so they won't be visible outside our generated "this/ex" package.

Converting from a wire format blob to this structure uses code like this:

        var data []byte = yourData // the binary blob of wire format data
        var person ex.Person
        if err := proto.Unmarshal(data, &person); err != nil {
                // handle decode problem, see err.
                return err
        }
        // person now holds the data you want.

If you must have a simple version, you will likely have to hand edit one. You could start with something like this:

$ cat this/ex/ex.pb.go | sed -n '/^type Person struct {/,/^}/p' | sed -e '/^[\t]\+[a-z].*$/d'

but you will need to write a function to import this by copying each of the exported fields from this/ex.Person to your Person definition. This is relatively easy for a simple type like ex.Person, but it will get complicated if you have a nested protobuf definition.