Small refactor of tables internals

src/model/index_counter.rs

@@ -251,13 +251,9 @@ impl<T: CountedItem> IndexCounter<T> {
 		TR: TableReplication,
 	{
 		let save_counter_entry = |entry: CounterEntry<T>| -> Result<(), Error> {
-			let entry_k = self
-				.table
-				.data
-				.tree_key(entry.partition_key(), entry.sort_key());
 			self.table
 				.data
-				.update_entry_with(&entry_k, |ent| match ent {
+				.update_entry_with(&entry.partition_key(), &entry.sort_key(), |ent| match ent {
 					Some(mut ent) => {
 						ent.merge(&entry);
 						ent

src/model/k2v/rpc.rs

@@ -273,14 +273,9 @@ impl K2VRpcHandler {
 	}
 
 	fn local_insert(&self, item: &InsertedItem) -> Result<Option<K2VItem>, Error> {
-		let tree_key = self
-			.item_table
-			.data
-			.tree_key(&item.partition, &item.sort_key);
-
 		self.item_table
 			.data
-			.update_entry_with(&tree_key[..], |ent| {
+			.update_entry_with(&item.partition, &item.sort_key, |ent| {
 				let mut ent = ent.unwrap_or_else(|| {
 					K2VItem::new(
 						item.partition.bucket_id,

src/table/data.rs

@@ -173,9 +173,8 @@ where
 
 	pub(crate) fn update_entry(&self, update_bytes: &[u8]) -> Result<(), Error> {
 		let update = self.decode_entry(update_bytes)?;
-		let tree_key = self.tree_key(update.partition_key(), update.sort_key());
 
-		self.update_entry_with(&tree_key[..], |ent| match ent {
+		self.update_entry_with(update.partition_key(), update.sort_key(), |ent| match ent {
 			Some(mut ent) => {
 				ent.merge(&update);
 				ent
@@ -187,11 +186,14 @@ where
 
 	pub fn update_entry_with(
 		&self,
-		tree_key: &[u8],
+		partition_key: &F::P,
+		sort_key: &F::S,
 		f: impl Fn(Option<F::E>) -> F::E,
 	) -> Result<Option<F::E>, Error> {
+		let tree_key = self.tree_key(partition_key, sort_key);
+
 		let changed = self.store.db().transaction(|mut tx| {
-			let (old_entry, old_bytes, new_entry) = match tx.get(&self.store, tree_key)? {
+			let (old_entry, old_bytes, new_entry) = match tx.get(&self.store, &tree_key)? {
 				Some(old_bytes) => {
 					let old_entry = self.decode_entry(&old_bytes).map_err(db::TxError::Abort)?;
 					let new_entry = f(Some(old_entry.clone()));
@@ -200,23 +202,23 @@ where
 				None => (None, None, f(None)),
 			};
 
-			// Scenario 1: the value changed, so of course there is a change
+			// Changed can be true in two scenarios
-			let value_changed = Some(&new_entry) != old_entry.as_ref();
+			// Scenario 1: the actual represented value changed,
-
+			//   so of course the messagepack encoding changed as well
 			// Scenario 2: the value didn't change but due to a migration in the
-			// data format, the messagepack encoding changed. In this case
+			//   data format, the messagepack encoding changed. In this case,
-			// we have to write the migrated value in the table and update
+			//   we also have to write the migrated value in the table and update
 			//   the associated Merkle tree entry.
 			let new_bytes = rmp_to_vec_all_named(&new_entry)
 				.map_err(Error::RmpEncode)
 				.map_err(db::TxError::Abort)?;
-			let encoding_changed = Some(&new_bytes[..]) != old_bytes.as_ref().map(|x| &x[..]);
+			let changed = Some(&new_bytes[..]) != old_bytes.as_deref();
 			drop(old_bytes);
 
-			if value_changed || encoding_changed {
+			if changed {
-				let new_bytes_hash = blake2sum(&new_bytes[..]);
+				let new_bytes_hash = blake2sum(&new_bytes);
-				tx.insert(&self.merkle_todo, tree_key, new_bytes_hash.as_slice())?;
+				tx.insert(&self.merkle_todo, &tree_key, new_bytes_hash.as_slice())?;
-				tx.insert(&self.store, tree_key, new_bytes)?;
+				tx.insert(&self.store, &tree_key, new_bytes)?;
 
 				self.instance
 					.updated(&mut tx, old_entry.as_ref(), Some(&new_entry))?;
@@ -242,7 +244,7 @@ where
 				let pk_hash = Hash::try_from(&tree_key[..32]).unwrap();
 				let nodes = self.replication.write_nodes(&pk_hash);
 				if nodes.first() == Some(&self.system.id) {
-					GcTodoEntry::new(tree_key.to_vec(), new_bytes_hash).save(&self.gc_todo)?;
+					GcTodoEntry::new(tree_key, new_bytes_hash).save(&self.gc_todo)?;
 				}
 			}
 
@@ -258,10 +260,11 @@ where
 			.db()
 			.transaction(|mut tx| match tx.get(&self.store, k)? {
 				Some(cur_v) if cur_v == v => {
+					let old_entry = self.decode_entry(v).map_err(db::TxError::Abort)?;
+
 					tx.remove(&self.store, k)?;
 					tx.insert(&self.merkle_todo, k, vec![])?;
 
-					let old_entry = self.decode_entry(v).map_err(db::TxError::Abort)?;
 					self.instance.updated(&mut tx, Some(&old_entry), None)?;
 					Ok(true)
 				}
@@ -285,10 +288,11 @@ where
 			.db()
 			.transaction(|mut tx| match tx.get(&self.store, k)? {
 				Some(cur_v) if blake2sum(&cur_v[..]) == vhash => {
+					let old_entry = self.decode_entry(&cur_v[..]).map_err(db::TxError::Abort)?;
+
 					tx.remove(&self.store, k)?;
 					tx.insert(&self.merkle_todo, k, vec![])?;
 
-					let old_entry = self.decode_entry(&cur_v[..]).map_err(db::TxError::Abort)?;
 					self.instance.updated(&mut tx, Some(&old_entry), None)?;
 					Ok(true)
 				}