Handle get_by_name for <1.28.0 when the GET endpoint wasn't available

Author: tsmith023

weaviate/collections/tenants/tenants.py

@@ -307,11 +307,22 @@ async def get_by_name(self, tenant: Union[str, Tenant]) -> Optional[TenantOutput
             `weaviate.UnexpectedStatusCodeError`
                 If Weaviate reports a non-OK status.
         """
+        self._connection._weaviate_version.check_is_at_least_1_25_0("The 'get_by_name' method")
         if self._validate_arguments:
             _validate_input(
                 _ValidateArgument(expected=[Union[str, Tenant]], name="tenant", value=tenant)
             )
         tenant_name = tenant.name if isinstance(tenant, Tenant) else tenant
+        if self._connection._weaviate_version.is_lower_than(1, 28, 0):
+            # For Weaviate versions < 1.28.0, we need to use the gRPC API
+            # such versions don't have RBAC so the filtering issue doesn't exist therein
+            tenants = await self.__get_with_grpc([tenant_name])
+            if len(tenants) == 0:
+                return None
+            return tenants[tenant_name]
+        # For Weaviate versions >= 1.28.0, we need to use the REST API
+        # as the gRPC API filters out tenants that are not accessible to the user
+        # due to RBAC requirements
         response = await self._connection.get(
             path=f"/schema/{self._name}/tenants/{tenant_name}",
             error_msg=f"Could not get tenant {tenant_name} for collection {self._name}",
@@ -321,10 +332,7 @@ async def get_by_name(self, tenant: Union[str, Tenant]) -> Optional[TenantOutput
         )
         if response.status_code == 404:
             return None
-        data = response.json()
-        if not data:
-            return None
-        return Tenant(**data)
+        return Tenant(**response.json())
 
     async def update(
         self, tenants: Union[TenantUpdateInputType, Sequence[TenantUpdateInputType]]