[Bug]: Amino JSON representation changed between cosmos-sdk 0.47 and 0.50

[pinosu]

Is there an existing issue for this?

• I have searched the existing issues

What happened?

we have a big blocker issue for Cosmos SDK 0.50 adoption with wasmd: with the upgrade Cosmos SDK the Amino JSON representation of certain things changed in a breaking way. This was observed for some Cosmos SDK message types and we now have it for wasmd types as well. In both cases we have signer breaking changes due to custom MarshalJSON implementations of custom Go types.
In case of wasmd there is e.g.

  // Msg json encoded message to be passed to the contract on migration
  bytes msg = 5 [ (gogoproto.casttype) = "RawContractMessage" ];

where RawContractMessage is marshalled as a JSON document instead of base64 in the Amino JSON sign doc. This is not respected anymore with SDK 0.50. In this gist there is expected and actual sign doc compared (see msg field).

Cosmos SDK Version

0.50

How to reproduce?

No response