The gRPC API does not allow us to delete relation tuples in bulk when Subject is not specified

[evgeniradev]

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Ory Network Project

No response

Describe the bug

The REST API allows us to delete relation tuples in bulk when the Subject is not specified. However, the gRPC API does not - it expects a Subject to be provided at all times and raises and error if it is missing.

Reproducing the bug

gRPC example in Ruby:

require 'ory/keto/relation_tuples/v1alpha2/write_service_services_pb'

relation_tuple = 
  Ory::Keto::RelationTuples::V1alpha2::RelationTuple.new(
    namespace: 'Namespace_A', 
    object: '123',
    relation: 'members'
  )

request = Ory::Keto::RelationTuples::V1alpha2::TransactRelationTuplesRequest.new(
  relation_tuple_deltas: [
    Ory::Keto::RelationTuples::V1alpha2::RelationTupleDelta.new(
      action: Ory::Keto::RelationTuples::V1alpha2::RelationTupleDelta::Action::ACTION_DELETE,
      relation_tuple:
    )
  ]
)

Ory::Keto::RelationTuples::V1alpha2::WriteService::Stub.new(
  OryKetoApiClient.base_write_api_url,
  :this_channel_is_insecure,
).transact_relation_tuples(request)

# GRPC::InvalidArgument: 3:subject is not allowed to be nil. debug_error_string:{UNKNOWN:Error received from peer  {created_time:"2024-10-30T09:28:01.470304+00:00", grpc_status:3, grpc_message:"subject is not allowed to be nil"}}

REST example in Ruby:

require 'http'

HTTP.headers(
  'Accept' => 'application/json',
  'Content-Type' => 'application/json'
).delete('http://localhost:4467/admin/relation-tuples?namespace=Namespace_A&object=123&relation=members')

Relevant log output

No response

Relevant configuration

No response

Version

v0.13.0-alpha.0

On which operating system are you observing this issue?

None

In which environment are you deploying?

None

Additional Context

No response