Shared reference to conversion rate metric value (#1034)

* shared conversion rate metric value

* clippy

bridges/relays/bin-ethereum/Cargo.toml

@@ -7,6 +7,7 @@ license = "GPL-3.0-or-later WITH Classpath-exception-2.0"
 
 [dependencies]
 ansi_term = "0.12"
+anyhow = "1.0"
 async-std = "1.9.0"
 async-trait = "0.1.42"
 clap = { version = "2.33.3", features = ["yaml"] }

bridges/relays/bin-ethereum/src/ethereum_exchange.rs

@@ -355,7 +355,7 @@ async fn run_single_transaction_relay(params: EthereumExchangeParams, eth_tx_has
 async fn run_auto_transactions_relay_loop(
 	params: EthereumExchangeParams,
 	eth_start_with_block_number: Option<u64>,
-) -> Result<(), String> {
+) -> anyhow::Result<()> {
 	let EthereumExchangeParams {
 		eth_params,
 		sub_params,
@@ -375,7 +375,7 @@ async fn run_auto_transactions_relay_loop(
 				.best_ethereum_finalized_block()
 				.await
 				.map_err(|err| {
-					format!(
+					anyhow::format_err!(
 						"Error retrieving best finalized Ethereum block from Substrate node: {:?}",
 						err
 					)

bridges/relays/bin-ethereum/src/ethereum_sync_loop.rs

@@ -292,7 +292,7 @@ pub async fn run(params: EthereumSyncParams) -> Result<(), RpcError> {
 		futures::future::pending(),
 	)
 	.await
-	.map_err(RpcError::SyncLoop)?;
+	.map_err(|e| RpcError::SyncLoop(e.to_string()))?;
 
 	Ok(())
 }

bridges/relays/bin-ethereum/src/substrate_sync_loop.rs

@@ -194,7 +194,7 @@ pub async fn run(params: SubstrateSyncParams) -> Result<(), RpcError> {
 		futures::future::pending(),
 	)
 	.await
-	.map_err(RpcError::SyncLoop)?;
+	.map_err(|e| RpcError::SyncLoop(e.to_string()))?;
 
 	Ok(())
 }