layout: prepare for write sets

src/table/replication/fullcopy.rs

@@ -27,6 +27,11 @@ pub struct TableFullReplication {
 }
 
 impl TableReplication for TableFullReplication {
+	fn storage_nodes(&self, _hash: &Hash) -> Vec<Uuid> {
+		let layout = self.system.cluster_layout();
+		layout.current().all_nodes().to_vec()
+	}
+
 	fn read_nodes(&self, _hash: &Hash) -> Vec<Uuid> {
 		vec![self.system.id]
 	}
@@ -34,8 +39,8 @@ impl TableReplication for TableFullReplication {
 		1
 	}
 
-	fn write_nodes(&self, _hash: &Hash) -> Vec<Uuid> {
-		self.system.cluster_layout().current().all_nodes().to_vec()
+	fn write_sets(&self, hash: &Hash) -> Vec<Vec<Uuid>> {
+		vec![self.storage_nodes(hash)]
 	}
 	fn write_quorum(&self) -> usize {
 		let nmembers = self.system.cluster_layout().current().all_nodes().len();

src/table/replication/parameters.rs

@@ -6,21 +6,23 @@ pub trait TableReplication: Send + Sync + 'static {
 	// See examples in table_sharded.rs and table_fullcopy.rs
 	// To understand various replication methods
 
+	/// The entire list of all nodes that store a partition
+	fn storage_nodes(&self, hash: &Hash) -> Vec<Uuid>;
+
 	/// Which nodes to send read requests to
 	fn read_nodes(&self, hash: &Hash) -> Vec<Uuid>;
 	/// Responses needed to consider a read succesfull
 	fn read_quorum(&self) -> usize;
 
 	/// Which nodes to send writes to
-	fn write_nodes(&self, hash: &Hash) -> Vec<Uuid>;
-	/// Responses needed to consider a write succesfull
+	fn write_sets(&self, hash: &Hash) -> Vec<Vec<Uuid>>;
+	/// Responses needed to consider a write succesfull in each set
 	fn write_quorum(&self) -> usize;
 	fn max_write_errors(&self) -> usize;
 
 	// Accessing partitions, for Merkle tree & sync
 	/// Get partition for data with given hash
 	fn partition_of(&self, hash: &Hash) -> Partition;
-
 	/// List of partitions and nodes to sync with in current layout
 	fn sync_partitions(&self) -> SyncPartitions;
 }

src/table/replication/sharded.rs

@@ -25,21 +25,19 @@ pub struct TableShardedReplication {
 }
 
 impl TableReplication for TableShardedReplication {
+	fn storage_nodes(&self, hash: &Hash) -> Vec<Uuid> {
+		self.system.cluster_layout().storage_nodes_of(hash)
+	}
+
 	fn read_nodes(&self, hash: &Hash) -> Vec<Uuid> {
-		self.system
-			.cluster_layout()
-			.current()
-			.nodes_of(hash, self.replication_factor)
+		self.system.cluster_layout().read_nodes_of(hash)
 	}
 	fn read_quorum(&self) -> usize {
 		self.read_quorum
 	}
 
-	fn write_nodes(&self, hash: &Hash) -> Vec<Uuid> {
-		self.system
-			.cluster_layout()
-			.current()
-			.nodes_of(hash, self.replication_factor)
+	fn write_sets(&self, hash: &Hash) -> Vec<Vec<Uuid>> {
+		self.system.cluster_layout().write_sets_of(hash)
 	}
 	fn write_quorum(&self) -> usize {
 		self.write_quorum
@@ -60,13 +58,7 @@ impl TableReplication for TableShardedReplication {
 			.current()
 			.partitions()
 			.map(|(partition, first_hash)| {
-				let mut storage_nodes = layout
-					.write_sets_of(&first_hash)
-					.map(|x| x.into_iter())
-					.flatten()
-					.collect::<Vec<_>>();
-				storage_nodes.sort();
-				storage_nodes.dedup();
+				let storage_nodes = layout.storage_nodes_of(&first_hash);
 				SyncPartition {
 					partition,
 					first_hash,