Merge pull request 'NLnet task 3' (#667) from nlnet-task3 into next-0.10

Reviewed-on: https://git.deuxfleurs.fr/Deuxfleurs/garage/pulls/667

3 files changed, 98 insertions, 22 deletions

diff --git a/src/table/replication/fullcopy.rs b/src/table/replication/fullcopy.rs
index 18682ace..30122f39 100644
--- a/src/table/replication/fullcopy.rs
+++ b/src/table/replication/fullcopy.rs
@@ -1,15 +1,22 @@
 use std::sync::Arc;
 
-use garage_rpc::ring::*;
+use garage_rpc::layout::*;
 use garage_rpc::system::System;
 use garage_util::data::*;
 
 use crate::replication::*;
 
+// TODO: find a way to track layout changes for this as well
+// The hard thing is that this data is stored also on gateway nodes,
+// whereas sharded data is stored only on non-Gateway nodes (storage nodes)
+// Also we want to be more tolerant to failures of gateways so we don't
+// want to do too much holding back of data when progress of gateway
+// nodes is not reported in the layout history's ack/sync/sync_ack maps.
+
 /// Full replication schema: all nodes store everything
-/// Writes are disseminated in an epidemic manner in the network
 /// Advantage: do all reads locally, extremely fast
 /// Inconvenient: only suitable to reasonably small tables
+/// Inconvenient: if some writes fail, nodes will read outdated data
 #[derive(Clone)]
 pub struct TableFullReplication {
 	/// The membership manager of this node
@@ -19,6 +26,13 @@ pub struct TableFullReplication {
 }
 
 impl TableReplication for TableFullReplication {
+	type WriteSets = Vec<Vec<Uuid>>;
+
+	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]
 	}
@@ -26,12 +40,11 @@ impl TableReplication for TableFullReplication {
 		1
 	}
 
-	fn write_nodes(&self, _hash: &Hash) -> Vec<Uuid> {
-		let ring = self.system.ring.borrow();
-		ring.layout.node_ids().to_vec()
+	fn write_sets(&self, hash: &Hash) -> Self::WriteSets {
+		vec![self.storage_nodes(hash)]
 	}
 	fn write_quorum(&self) -> usize {
-		let nmembers = self.system.ring.borrow().layout.node_ids().len();
+		let nmembers = self.system.cluster_layout().current().all_nodes().len();
 		if nmembers > self.max_faults {
 			nmembers - self.max_faults
 		} else {
@@ -45,7 +58,18 @@ impl TableReplication for TableFullReplication {
 	fn partition_of(&self, _hash: &Hash) -> Partition {
 		0u16
 	}
-	fn partitions(&self) -> Vec<(Partition, Hash)> {
-		vec![(0u16, [0u8; 32].into())]
+
+	fn sync_partitions(&self) -> SyncPartitions {
+		let layout = self.system.cluster_layout();
+		let layout_version = layout.current().version;
+		SyncPartitions {
+			layout_version,
+			partitions: vec![SyncPartition {
+				partition: 0u16,
+				first_hash: [0u8; 32].into(),
+				last_hash: [0xff; 32].into(),
+				storage_sets: vec![layout.current().all_nodes().to_vec()],
+			}],
+		}
 	}
 }
diff --git a/src/table/replication/parameters.rs b/src/table/replication/parameters.rs
index f00815a2..78470f35 100644
--- a/src/table/replication/parameters.rs
+++ b/src/table/replication/parameters.rs
@@ -1,25 +1,44 @@
-use garage_rpc::ring::*;
+use garage_rpc::layout::*;
 use garage_util::data::*;
 
 /// Trait to describe how a table shall be replicated
 pub trait TableReplication: Send + Sync + 'static {
+	type WriteSets: AsRef<Vec<Vec<Uuid>>> + AsMut<Vec<Vec<Uuid>>> + 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) -> Self::WriteSets;
+	/// 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 existing partitions
-	fn partitions(&self) -> Vec<(Partition, Hash)>;
+	/// List of partitions and nodes to sync with in current layout
+	fn sync_partitions(&self) -> SyncPartitions;
+}
+
+#[derive(Debug)]
+pub struct SyncPartitions {
+	pub layout_version: u64,
+	pub partitions: Vec<SyncPartition>,
+}
+
+#[derive(Debug)]
+pub struct SyncPartition {
+	pub partition: Partition,
+	pub first_hash: Hash,
+	pub last_hash: Hash,
+	pub storage_sets: Vec<Vec<Uuid>>,
 }
diff --git a/src/table/replication/sharded.rs b/src/table/replication/sharded.rs
index 1cf964af..8ba3700f 100644
--- a/src/table/replication/sharded.rs
+++ b/src/table/replication/sharded.rs
@@ -1,6 +1,6 @@
 use std::sync::Arc;
 
-use garage_rpc::ring::*;
+use garage_rpc::layout::*;
 use garage_rpc::system::System;
 use garage_util::data::*;
 
@@ -25,17 +25,21 @@ pub struct TableShardedReplication {
 }
 
 impl TableReplication for TableShardedReplication {
+	type WriteSets = WriteLock<Vec<Vec<Uuid>>>;
+
+	fn storage_nodes(&self, hash: &Hash) -> Vec<Uuid> {
+		self.system.cluster_layout().storage_nodes_of(hash)
+	}
+
 	fn read_nodes(&self, hash: &Hash) -> Vec<Uuid> {
-		let ring = self.system.ring.borrow();
-		ring.get_nodes(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> {
-		let ring = self.system.ring.borrow();
-		ring.get_nodes(hash, self.replication_factor)
+	fn write_sets(&self, hash: &Hash) -> Self::WriteSets {
+		self.system.layout_manager.write_sets_of(hash)
 	}
 	fn write_quorum(&self) -> usize {
 		self.write_quorum
@@ -45,9 +49,38 @@ impl TableReplication for TableShardedReplication {
 	}
 
 	fn partition_of(&self, hash: &Hash) -> Partition {
-		self.system.ring.borrow().partition_of(hash)
+		self.system.cluster_layout().current().partition_of(hash)
 	}
-	fn partitions(&self) -> Vec<(Partition, Hash)> {
-		self.system.ring.borrow().partitions()
+
+	fn sync_partitions(&self) -> SyncPartitions {
+		let layout = self.system.cluster_layout();
+		let layout_version = layout.ack_map_min();
+
+		let mut partitions = layout
+			.current()
+			.partitions()
+			.map(|(partition, first_hash)| {
+				let storage_sets = layout.storage_sets_of(&first_hash);
+				SyncPartition {
+					partition,
+					first_hash,
+					last_hash: [0u8; 32].into(), // filled in just after
+					storage_sets,
+				}
+			})
+			.collect::<Vec<_>>();
+
+		for i in 0..partitions.len() {
+			partitions[i].last_hash = if i + 1 < partitions.len() {
+				partitions[i + 1].first_hash
+			} else {
+				[0xFFu8; 32].into()
+			};
+		}
+
+		SyncPartitions {
+			layout_version,
+			partitions,
+		}
 	}
 }