db-snapshot: Add error handling to metadata snapshot creation

Fix #920

src/model/snapshot.rs

@@ -43,13 +43,32 @@ pub fn snapshot_metadata(garage: &Garage) -> Result<(), Error> {
 
 	let mut snapshots_dir = garage.config.metadata_dir.clone();
 	snapshots_dir.push("snapshots");
-	fs::create_dir_all(&snapshots_dir)?;
+	if let Err(e) = fs::create_dir_all(&snapshots_dir) {
+		drop(lock);
+		error!(
+			"Failed to create snapshots directory '{}': {}",
+			snapshots_dir.display(),
+			e
+		);
+		return Err(Error::Message(format!(
+			"Failed to create snapshots directory '{}': {}",
+			snapshots_dir.display(),
+			e
+		)));
+	}
 
 	let mut new_path = snapshots_dir.clone();
 	new_path.push(chrono::Utc::now().to_rfc3339_opts(chrono::SecondsFormat::Secs, true));
 
 	info!("Snapshotting metadata db to {}", new_path.display());
-	garage.db.snapshot(&new_path)?;
+	if let Err(e) = garage.db.snapshot(&new_path) {
+		drop(lock);
+		error!("Failed to snapshot metadata db: {}", e);
+		return Err(Error::Message(format!(
+			"Failed to snapshot metadata db: {}",
+			e
+		)));
+	}
 	info!("Metadata db snapshot finished");
 
 	if let Err(e) = cleanup_snapshots(&snapshots_dir) {