Fixes for Millau-Rialto Deployment (paritytech#493)

* Expose two nodes publicly through brucke.link

* Use flags for GNU `sed` instead of BSD `sed`

* Update Substrate relay entrypoint scripts to initialize bridge

* Add Rialto to Millau relay to Compose deployment

* Stop initializing Rialto chain through chainspec

* Include logging for Substrate pallet

* Make Rialto to Millau entrypoint executable

* Use YAML references for relay components

* Use published Substrate Relay image

* Relay messages from Millau to Rialto

* Use Bob nodes to serve message lane

* Fix some port number issues for PoA-Rialto deployment

* Stop directly referencing `environment` anchor in nodes

* Add probable cause to relayer error message

* Edit monitoring config file in-place

* Add some sleep time between bridge init call and starting relays

* Expose grafana.

* Use Root key as bridge pallet owner

In our case that's going to be Alice since she's Root for our Dev
and Local chains.

Co-authored-by: Tomasz Drwięga <tomasz@parity.io>

bridges/bin/millau/node/src/chain_spec.rs

@@ -158,7 +158,7 @@ fn testnet_genesis(
 		pallet_substrate_bridge: Some(BridgeRialtoConfig {
 			// We'll initialize the pallet with a dispatchable instead.
 			init_data: None,
-			owner: None,
+			owner: Some(root_key.clone()),
 		}),
 		pallet_sudo: Some(SudoConfig { key: root_key }),
 		pallet_session: Some(SessionConfig {

bridges/bin/rialto/node/src/chain_spec.rs

@@ -157,7 +157,11 @@ fn testnet_genesis(
 		pallet_grandpa: Some(GrandpaConfig {
 			authorities: Vec::new(),
 		}),
-		pallet_substrate_bridge: load_millau_bridge_config(),
+		pallet_substrate_bridge: Some(BridgeMillauConfig {
+			// We'll initialize the pallet with a dispatchable instead.
+			init_data: None,
+			owner: Some(root_key.clone()),
+		}),
 		pallet_sudo: Some(SudoConfig { key: root_key }),
 		pallet_session: Some(SessionConfig {
 			keys: initial_authorities
@@ -183,10 +187,3 @@ fn load_kovan_bridge_config() -> Option<BridgeKovanConfig> {
 		initial_validators: rialto_runtime::kovan::genesis_validators(),
 	})
 }
-
-fn load_millau_bridge_config() -> Option<BridgeMillauConfig> {
-	Some(BridgeMillauConfig {
-		init_data: None,
-		owner: Some([0; 32].into()),
-	})
-}

bridges/relays/substrate/src/headers_target.rs

@@ -91,11 +91,11 @@ where
 		let decoded_response: Vec<(P::Number, P::Hash)> =
 			Decode::decode(&mut &encoded_response.0[..]).map_err(SubstrateError::ResponseParseFailed)?;
 
-		let best_header = decoded_response.last().ok_or_else(|| {
-			SubstrateError::ResponseParseFailed(
-				"Parsed an empty list of headers, we should always have at least one.".into(),
-			)
-		})?;
+		const WARNING_MSG: &str = "Parsed an empty list of headers, we should always have at least
+									one. Has the bridge pallet been initialized yet?";
+		let best_header = decoded_response
+			.last()
+			.ok_or_else(|| SubstrateError::ResponseParseFailed(WARNING_MSG.into()))?;
 		let best_header_id = HeaderId(best_header.0, best_header.1);
 		Ok(best_header_id)
 	}