Fix issue with requested to revoke before registry creation

aries_cloudagent/ledger/indy_vdr.py

@@ -1092,6 +1092,29 @@ async def get_revoc_reg_delta(
             ) from err
 
         response_value = response["data"]["value"]
+        accum_to = response_value.get("accum_to")
+
+        # If accum_to is not present, then the timestamp_to was before the registry
+        # was created. In this case, we need to fetch the registry creation timestamp and
+        # re-calculate the delta.
+        if not accum_to:
+            try:
+                (_, timestamp) = await self.get_revoc_reg_entry(
+                    revoc_reg_id, int(time())
+                )
+                fetch_req = ledger.build_get_revoc_reg_delta_request(
+                    public_info and public_info.did,
+                    revoc_reg_id,
+                    timestamp_from,
+                    timestamp,
+                )
+                response = await self._submit(fetch_req, sign_did=public_info)
+                response_value = response["data"]["value"]
+            except VdrError as err:
+                raise LedgerError(
+                    f"get_revoc_reg_delta failed for revoc_reg_id='{revoc_reg_id}'"
+                ) from err
+
         delta_value = {
             "accum": response_value["accum_to"]["value"]["accum"],
             "issued": response_value.get("issued", []),

aries_cloudagent/ledger/tests/test_indy_vdr.py

@@ -972,6 +972,56 @@ async def test_get_revoc_reg_delta(
                 1234567890,
             )
 
+    @pytest.mark.asyncio
+    async def test_get_revoc_reg_delta_without_accum_to(
+        self,
+        ledger: IndyVdrLedger,
+    ):
+        async with ledger:
+            reg_id = (
+                "55GkHamhTU1ZbTbV2ab9DE:4:55GkHamhTU1ZbTbV2ab9DE:3:CL:99:tag:CL_ACCUM:0"
+            )
+            ledger.pool_handle.submit_request.side_effect = [
+                # First call to get_revoc_reg_delta
+                {
+                    "data": {
+                        "value": {},
+                        "revocRegDefId": reg_id,
+                    },
+                },
+                # Get registry with test_get_revoc_reg_entry
+                {
+                    "data": {
+                        "id": reg_id,
+                        "txnTime": 1234567890,
+                        "value": "...",
+                        "revocRegDefId": reg_id,
+                    },
+                },
+                # Second call to get_revoc_reg_delta
+                {
+                    "data": {
+                        "value": {
+                            "accum_to": {
+                                "value": {"accum": "ACCUM"},
+                                "txnTime": 1234567890,
+                            },
+                            "issued": [1, 2],
+                            "revoked": [3, 4],
+                        },
+                        "revocRegDefId": reg_id,
+                    },
+                },
+            ]
+            result = await ledger.get_revoc_reg_delta(reg_id)
+            assert result == (
+                {
+                    "ver": "1.0",
+                    "value": {"accum": "ACCUM", "issued": [1, 2], "revoked": [3, 4]},
+                },
+                1234567890,
+            )
+
     @pytest.mark.asyncio
     async def test_send_revoc_reg_def(
         self,