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@googlebot I signed it!

@haberman I assume you would be the correct person to review this further?

(Thanks for your work on the Ruby protobuf support!)

@haberman Ping on this, tagging you since you seem to be the primary maintainer for the Ruby bindings - not sure if I missed anything here. Appreciate the help - thank you :)

Hi @lfittl , I'm sorry for my slow reply on this.

I'm somewhat reluctant to go farther down this path of extending the DSL, because it is an un-winnable game of whack-a-mole. The DSL fundamentally can't represent all options, particular custom options that are used in their own definition:

syntax = "proto3";

import "google/protobuf/descriptor.proto";

extend google.protobuf.FieldOptions {
  optional int32 foo_option = 1000 [(foo_option) = 5];
}

That said, the fact that json_name is a member of FieldDescriptorProto (and not FieldOptions) does make the PR more compatible with a future world where we do handle options correctly. So maybe we can move forward with this now.

Hi @lfittl , I'm sorry for my slow reply on this.

No worries, I know the same from my own open source projects, thanks for taking a look!

I'm somewhat reluctant to go farther down this path of extending the DSL, because it is an un-winnable game of whack-a-mole. The DSL fundamentally can't represent all options, particular custom options that are used in their own definition:

syntax = "proto3";

import "google/protobuf/descriptor.proto";

extend google.protobuf.FieldOptions {
  optional int32 foo_option = 1000 [(foo_option) = 5];
}

That said, the fact that json_name is a member of FieldDescriptorProto (and not FieldOptions) does make the PR more compatible with a future world where we do handle options correctly. So maybe we can move forward with this now.

Yeah, I see how it's important to handle this generically at some point - but I think it still makes sense to do this now, since it allows use of json_name which seems to me one of the core features of Proto3 (as opposed to other custom field tags).

I've addressed the review comments you shared, and also added a test that covers this, to ensure it doesn't break by accident in the future.