Refactor model stuff, including cleaner CRDTs

src/model/object_table.rs

@@ -5,6 +5,7 @@ use std::sync::Arc;
 use garage_util::background::BackgroundRunner;
 use garage_util::data::*;
 
+use garage_table::crdt::*;
 use garage_table::table_sharded::*;
 use garage_table::*;
 
@@ -70,7 +71,7 @@ pub enum ObjectVersionState {
 	Aborted,
 }
 
-impl ObjectVersionState {
+impl CRDT for ObjectVersionState {
 	fn merge(&mut self, other: &Self) {
 		use ObjectVersionState::*;
 		match other {
@@ -91,37 +92,30 @@ impl ObjectVersionState {
 	}
 }
 
-#[derive(PartialEq, Clone, Debug, Serialize, Deserialize)]
+#[derive(PartialEq, Eq, PartialOrd, Ord, Clone, Debug, Serialize, Deserialize)]
 pub enum ObjectVersionData {
 	DeleteMarker,
 	Inline(ObjectVersionMeta, #[serde(with = "serde_bytes")] Vec<u8>),
 	FirstBlock(ObjectVersionMeta, Hash),
 }
 
-#[derive(PartialEq, Clone, Debug, Serialize, Deserialize)]
+impl AutoCRDT for ObjectVersionData {
+	const WARN_IF_DIFFERENT: bool = true;
+}
+
+#[derive(PartialEq, Eq, PartialOrd, Ord, Clone, Debug, Serialize, Deserialize)]
 pub struct ObjectVersionMeta {
 	pub headers: ObjectVersionHeaders,
 	pub size: u64,
 	pub etag: String,
 }
 
-#[derive(PartialEq, Clone, Debug, Serialize, Deserialize)]
+#[derive(PartialEq, Eq, PartialOrd, Ord, Clone, Debug, Serialize, Deserialize)]
 pub struct ObjectVersionHeaders {
 	pub content_type: String,
 	pub other: BTreeMap<String, String>,
 }
 
-impl ObjectVersionData {
-	fn merge(&mut self, b: &Self) {
-		if *self != *b {
-			warn!(
-				"Inconsistent object version data: {:?} (local) vs {:?} (remote)",
-				self, b
-			);
-		}
-	}
-}
-
 impl ObjectVersion {
 	fn cmp_key(&self) -> (u64, UUID) {
 		(self.timestamp, self.uuid)
@@ -154,8 +148,11 @@ impl Entry<String, String> for Object {
 	fn sort_key(&self) -> &String {
 		&self.key
 	}
+}
 
+impl CRDT for Object {
 	fn merge(&mut self, other: &Self) {
+		// Merge versions from other into here
 		for other_v in other.versions.iter() {
 			match self
 				.versions
@@ -169,6 +166,9 @@ impl Entry<String, String> for Object {
 				}
 			}
 		}
+
+		// Remove versions which are obsolete, i.e. those that come
+		// before the last version which .is_complete().
 		let last_complete = self
 			.versions
 			.iter()
@@ -212,13 +212,8 @@ impl TableSchema for ObjectTable {
 						}
 					};
 					if newly_deleted {
-						let deleted_version = Version::new(
-							v.uuid,
-							old_v.bucket.clone(),
-							old_v.key.clone(),
-							true,
-							vec![],
-						);
+						let deleted_version =
+							Version::new(v.uuid, old_v.bucket.clone(), old_v.key.clone(), true);
 						version_table.insert(&deleted_version).await?;
 					}
 				}