protocol bufferの定義でmessageのネストと配列を使う場合のメモ

message Author {
  string name = 1;
}

message Book {
  string title = 1;
  Author author = 2;
  repeated string tags = 3;
}

clientからのリクエスト時

r, err := c.PostBook(ctx, &pb.Book{
  Title: "New Title",
  Author: &pb.Author{Name: "Doyle"},
  Tags: []string{"go", "grpc"},
})