Made contract addresses for query NymdClient construction optional

Similarly as it is the case when creating SigningNymdClient

common/client-libs/validator-client/src/client.rs

@@ -132,14 +132,14 @@ impl Client<QueryNymdClient> {
         let validator_api_client = validator_api::Client::new(config.api_url.clone());
         let nymd_client = NymdClient::connect(
             config.nymd_url.as_str(),
-            config.mixnet_contract_address.clone().unwrap_or_else(|| {
+            Some(config.mixnet_contract_address.clone().unwrap_or_else(|| {
                 cosmrs::AccountId::from_str(network_defaults::DEFAULT_MIXNET_CONTRACT_ADDRESS)
                     .unwrap()
-            }),
-            config.vesting_contract_address.clone().unwrap_or_else(|| {
+            })),
+            Some(config.vesting_contract_address.clone().unwrap_or_else(|| {
                 cosmrs::AccountId::from_str(network_defaults::DEFAULT_VESTING_CONTRACT_ADDRESS)
                     .unwrap()
-            }),
+            })),
         )?;
 
         Ok(Client {
@@ -157,8 +157,8 @@ impl Client<QueryNymdClient> {
     pub fn change_nymd(&mut self, new_endpoint: Url) -> Result<(), ValidatorClientError> {
         self.nymd = NymdClient::connect(
             new_endpoint.as_ref(),
-            self.mixnet_contract_address.clone().unwrap(),
-            self.vesting_contract_address.clone().unwrap(),
+            self.mixnet_contract_address.clone(),
+            self.vesting_contract_address.clone(),
         )?;
         Ok(())
     }

common/client-libs/validator-client/src/nymd/mod.rs

@@ -57,16 +57,16 @@ pub struct NymdClient<C> {
 impl NymdClient<QueryNymdClient> {
     pub fn connect<U>(
         endpoint: U,
-        mixnet_contract_address: AccountId,
-        vesting_contract_address: AccountId,
+        mixnet_contract_address: Option<AccountId>,
+        vesting_contract_address: Option<AccountId>,
     ) -> Result<NymdClient<QueryNymdClient>, NymdError>
     where
         U: TryInto<HttpClientUrl, Error = TendermintRpcError>,
     {
         Ok(NymdClient {
             client: QueryNymdClient::new(endpoint)?,
-            mixnet_contract_address: Some(mixnet_contract_address),
-            vesting_contract_address: Some(vesting_contract_address),
+            mixnet_contract_address,
+            vesting_contract_address,
             client_address: None,
             custom_gas_limits: Default::default(),
             simulated_gas_multiplier: DEFAULT_SIMULATED_GAS_MULTIPLIER,