Go types override

[borosr]

I created three new field options called:

• go_type - the go type to override the existing one
• go_import - the import to add into the import statement
• go_import_alias - the alias of the import

Try

Run the following test file cmd/protoc-gen-go/internal_gengo/main_test.go.
This will generate 3 go files, the test.pb.go will be the interesting one.

Example proto file

Note: The field option extend part was extracted into a common proto file, so it can be imported. The location of this file is in cmd/protoc-gen-go/internal_gengo/test_data/config.proto.

syntax = "proto3";

package proto;

option go_package = ".;proto";

// This part is needed to extend messages
import "google/protobuf/descriptor.proto";

extend google.protobuf.FieldOptions {
  optional string go_type = 1000;
  optional string go_import = 1001;
  optional string go_import_alias = 1002;
}

message RepeatedString {
}

message Test {
  int64 created_at = 1 [(go_type) = "time.Time", (go_import) = "time"];
  map<uint64, RepeatedString> map_field = 2 [(go_type) = "map[uint64][]string", (go_import) = ""];
  string test = 3;
  string optStr = 43 [(go_type) = "null.String", (go_import) = "github.com/volatiletech/null/v9", (go_import_alias) = "null"];
}

[PumpkinSeed]

I tried to use it with libprotoc 3.21.7 as the parser, and it didn't do anything which is related to type override. Can you check that it's the correct version for libprotoc or something other issue.

Note: The parser what the test is using is not the original protoc, I found something which was an open-source copy written in Go.

protoc --version
libprotoc 3.21.7

[PumpkinSeed]

After a successful type override the getter's default return is NOT respecting the override value. Example:

func (x *TransactionRequest) GetIdempotencyTime() null.Uint64 {
    if x != nil {
        return x.IdempotencyTime
    }
    return ""
}