Ursula on publishes ferveo public key on-chain when none is present to save gas.

nucypher/blockchain/eth/actors.py

@@ -324,16 +324,17 @@ class Ritualist(BaseActor):
             condition_provider_uris
         )
 
-        # TODO: check if the ferveo public key is set on the blockchain
-        # There is no boolean interface on-chain to determine this.
+        self.set_provider_public_key()
+
+    def set_provider_public_key(self):
         # Here we're assuming there is one global key per node.
-        # onchain_ferveo_public_key = self.coordinator_agent.get_provider_public_key(
-        #     self.staking_provider_address,
-        #     0
-        # )
-        self.coordinator_agent.set_provider_public_key(
-            self.ritual_power.public_key(), transacting_power=self.transacting_power
+        is_provider_key_set = self.coordinator_agent.is_provider_public_key_set(
+            self.staking_provider_address,
         )
+        if not is_provider_key_set:
+            self.coordinator_agent.set_provider_public_key(
+                self.ritual_power.public_key(), transacting_power=self.transacting_power
+            )
 
     @staticmethod
     def _is_permitted_condition_chain(chain_id: int) -> bool:

nucypher/blockchain/eth/agents.py

@@ -794,6 +794,11 @@ class CoordinatorAgent(EthereumContractAgent):
         ).call()
         return result
 
+    @contract_api(CONTRACT_CALL)
+    def is_provider_public_key_set(self, staking_provider: ChecksumAddress) -> bool:
+        result = self.contract.functions.isProviderPublicKeySet(staking_provider).call()
+        return result
+
     @contract_api(TRANSACTION)
     def set_provider_public_key(
         self, public_key: FerveoPublicKey, transacting_power: TransactingPower