protoc-gen-swagger: json_names_for_fields=true does not respect json_name for *nested* path parameters

[brocaar]

This is probably related to #1084 which was fixed by #1084.

Version: v1.14.3

service DeviceService {
    rpc Get(GetDeviceRequest) returns (GetDeviceResponse) {
        option (google.api.http) = {
            get: "/api/devices/{dev_eui}"
        };
    }

message GetDeviceRequest {
    // Device EUI (HEX encoded).
    string dev_eui = 1 [json_name = "devEUI"];
}

Does result in the expected endpoint: /api/devices/{devEUI}.

However, if the Protobuf definition is modified to:

service DeviceService {
    rpc Get(GetDeviceRequest) returns (GetDeviceResponse) {
        option (google.api.http) = {
            get: "/api/devices/{device.dev_eui}"
        };
    }

message GetDeviceRequest {v1.14.3
    Device device = 1;
}

message Device {
    // Device EUI (HEX encoded).
    string dev_eui = 1 [json_name = "devEUI"];
}

The expected endpoint would be: /api/devices/{device.devEUI}.
However, the actual generated endpoint is: /api/devices/{device.devEui}.

Could it be that in case of a nested argument, the GetJsonName() is not triggered?

[johanbrandhorst]

Seems right. Are you saying this was broken by the change or that it wasn't supported to begin with and still isn't supported? Would you be interested in fixing this?

CC @xin-au

[brocaar]

@johanbrandhorst I don't think this was ever supported. It might be a case which was not captured in #1084

[xin-au]

@johanbrandhorst , @brocaar , thanks for pointing it out! I will be working on it. Sorry about that.

[brocaar]

Thank you @xin-au !

[xin-au]

@brocaar , @johanbrandhorst , quick update:
I was investigating on it. And I realized that if a reserved json name is defined not in the root level of the request data structure of a grpc call, then that reserved json name will not be in the field data structure(the data structure which should carry this info, its name FieldDescriptorProto). So, the root cause is the reserved json names are not read recursively. I was trying to fix it. And found that this structure FieldDescriptorProto is from protobuf code, we could do nothing about it.
Let me try if there is any workaround.

[xin-au]

@brocaar , @johanbrandhorst , update:
Still working on it, found some solution could fix it.

[xin-au]

@brocaar @johanbrandhorst , just created a PR #1191
@brocaar , by chance you could clone and build it and try if this will be what you expect to unblock you.