Check for duplicate entries between user supplied endpoints and fallback endpoints. All endpoints for a specific chain should be unique.

nucypher/blockchain/eth/actors.py

@@ -275,13 +275,7 @@ class Operator(BaseActor):
     def connect_condition_providers(
         self, endpoints: Dict[int, List[str]]
     ) -> DefaultDict[int, List[HTTPProvider]]:
-        providers = defaultdict(list)
-
-        # de-duplicate, preserving order
-        deduplicated = {}
-        for chain_id, uris in endpoints.items():
-            deduplicated[chain_id] = list(dict.fromkeys(uris))
-        endpoints = deduplicated
+        providers = defaultdict(list)  # use list to maintain order
 
         # check that we have endpoints for all condition chains
         if set(self.domain.condition_chain_ids) != set(endpoints):
@@ -290,7 +284,10 @@ class Operator(BaseActor):
                 f"{set(self.domain.condition_chain_ids) - set(endpoints)}"
             )
 
-        # check that each chain id is supported
+        # ensure that no endpoint uri for a specific chain is repeated
+        duplicated_endpoint_check = defaultdict(set)
+
+        # User-defined endpoints for chains
         for chain_id, endpoints in endpoints.items():
             if not self._is_permitted_condition_chain(chain_id):
                 raise NotImplementedError(
@@ -299,6 +296,12 @@ class Operator(BaseActor):
 
             # connect to each endpoint and check that they are on the correct chain
             for uri in endpoints:
+                if uri in duplicated_endpoint_check[chain_id]:
+                    self.log.warn(
+                        f"Duplicated user-supplied blockchain uri, {uri}, for condition evaluation on chain {chain_id}; skipping"
+                    )
+                    continue
+
                 provider = self._make_condition_provider(uri)
                 if int(Web3(provider).eth.chain_id) != int(chain_id):
                     raise self.ActorError(
@@ -310,13 +313,20 @@ class Operator(BaseActor):
                         f"user-supplied condition RPC endpoint {uri} is unhealthy"
                     )
                 providers[int(chain_id)].append(provider)
+                duplicated_endpoint_check[chain_id].add(uri)
 
         # Ingest default/fallback RPC providers for each chain
         for chain_id in self.domain.condition_chain_ids:
             default_endpoints = get_healthy_default_rpc_endpoints(chain_id)
             for uri in default_endpoints:
+                if uri in duplicated_endpoint_check[chain_id]:
+                    self.log.warn(
+                        f"Duplicated fallback blockchain uri, {uri}, for condition evaluation on chain {chain_id}; skipping"
+                    )
+                    continue
                 provider = self._make_condition_provider(uri)
                 providers[chain_id].append(provider)
+                duplicated_endpoint_check[chain_id].add(uri)
 
         humanized_chain_ids = ", ".join(
             _CONDITION_CHAINS[chain_id] for chain_id in providers

nucypher/blockchain/eth/utils.py

@@ -172,7 +172,7 @@ def get_healthy_default_rpc_endpoints(chain_id: int) -> List[str]:
     healthy = [
         endpoint for endpoint in chain_endpoints if rpc_endpoint_health_check(endpoint)
     ]
-    LOGGER.info(f"Healthy RPC endpoints for chain ID {chain_id}: {healthy}")
+    LOGGER.info(f"Healthy default RPC endpoints for chain ID {chain_id}: {healthy}")
     if not healthy:
         LOGGER.warn(
             f"No healthy default RPC endpoints available for chain ID {chain_id}"