Gateway does not parse oneof types correctly when using camelCase

[seanlaff]

Enums like

message GetRolesRequest {
  oneof get {
    // roles's project
    string project_id = 4;
    // cluster roles
    bool cluster = 5;
  }
}

will not be parsed correctly through the gateway with the camelCase flag. project_id succeeds but projectId does not.

The issue looks to be here :

grpc-gateway/runtime/query.go

Lines 120 to 128 in 7f57073

	if op, ok := props.OneofTypes[name]; ok {
	v := reflect.New(op.Type.Elem())
	field := m.Field(op.Field)
	if !field.IsNil() {
	return reflect.Value{}, nil, fmt.Errorf("field already set for %s oneof", props.Prop[op.Field].OrigName)
	}
	field.Set(v)
	return v.Elem().Field(0), op.Prop, nil
	}

There's a map of oneofs that we loop over, however they key of the map is the name with the underscore, so given a camelCase param, it will never find it.

[johanbrandhorst]

Nice find. Have you looked at implementing a fix? I would be happy to review it.