[service] better logging

service/src/account_funding.rs

@@ -146,7 +146,7 @@ fn bootstrap_funds_from_alice(
             "funding amount is too high: please change EXISTENTIAL_DEPOSIT_FACTOR_FOR_INIT_FUNDS ({:?})",
             funding_amount
         );
-		return Err(Error::ApplicationSetup)
+		return Err(Error::ApplicationSetup("Alice funds too low".into()))
 	}
 
 	let mut alice_signer_api = api.clone();

service/src/error.rs

@@ -38,8 +38,8 @@ pub enum Error {
 	Serialization(#[from] serde_json::Error),
 	#[error("{0}")]
 	FromUtf8(#[from] std::string::FromUtf8Error),
-	#[error("Application setup error!")]
-	ApplicationSetup,
+	#[error("Application setup error: {0}")]
+	ApplicationSetup(String),
 	#[error("Failed to find any peer worker")]
 	NoPeerWorkerFound,
 	#[error("No worker for shard {0} found on parentchain")]

service/src/parentchain_handler.rs

@@ -149,6 +149,21 @@ where
 			.ok_or(Error::MissingLastFinalizedBlock)?;
 		let curr_block_number = curr_block.block.header().number();
 
+		if last_synced_header.number == curr_block_number {
+			println!(
+				"[{:?}] No sync necessary, we are already up to date with block {}",
+				id, last_synced_header.number,
+			);
+			return Ok(last_synced_header)
+		}
+
+		if last_synced_header.number > curr_block_number {
+			return Err(Error::ApplicationSetup(format!(
+				"[{:?}] Bad config, last synced header {} is recent than current parentchain head {}",
+				id, last_synced_header.number, curr_block_number
+			)))
+		}
+
 		println!(
 			"[{:?}] Syncing blocks from {} to {}",
 			id, last_synced_header.number, curr_block_number