1 files changed, 131 insertions, 0 deletions
diff --git a/src/core/version_table.rs b/src/core/version_table.rs
new file mode 100644
index 00000000..ae32e5cb
--- /dev/null
+++ b/src/core/version_table.rs
@@ -0,0 +1,131 @@
+use async_trait::async_trait;
+use serde::{Deserialize, Serialize};
+use std::sync::Arc;
+
+use garage_util::background::BackgroundRunner;
+use garage_util::data::*;
+use garage_util::error::Error;
+
+use garage_table::table_sharded::*;
+use garage_table::*;
+
+use crate::block_ref_table::*;
+
+#[derive(PartialEq, Clone, Debug, Serialize, Deserialize)]
+pub struct Version {
+	// Primary key
+	pub uuid: UUID,
+
+	// Actual data: the blocks for this version
+	pub deleted: bool,
+	blocks: Vec<VersionBlock>,
+
+	// Back link to bucket+key so that we can figure if
+	// this was deleted later on
+	pub bucket: String,
+	pub key: String,
+}
+
+impl Version {
+	pub fn new(
+		uuid: UUID,
+		bucket: String,
+		key: String,
+		deleted: bool,
+		blocks: Vec<VersionBlock>,
+	) -> Self {
+		let mut ret = Self {
+			uuid,
+			deleted,
+			blocks: vec![],
+			bucket,
+			key,
+		};
+		for b in blocks {
+			ret.add_block(b)
+				.expect("Twice the same VersionBlock in Version constructor");
+		}
+		ret
+	}
+	/// Adds a block if it wasn't already present
+	pub fn add_block(&mut self, new: VersionBlock) -> Result<(), ()> {
+		match self.blocks.binary_search_by(|b| b.offset.cmp(&new.offset)) {
+			Err(i) => {
+				self.blocks.insert(i, new);
+				Ok(())
+			}
+			Ok(_) => Err(()),
+		}
+	}
+	pub fn blocks(&self) -> &[VersionBlock] {
+		&self.blocks[..]
+	}
+}
+
+#[derive(PartialEq, Clone, Debug, Serialize, Deserialize)]
+pub struct VersionBlock {
+	pub offset: u64,
+	pub hash: Hash,
+}
+
+impl Entry<Hash, EmptyKey> for Version {
+	fn partition_key(&self) -> &Hash {
+		&self.uuid
+	}
+	fn sort_key(&self) -> &EmptyKey {
+		&EmptyKey
+	}
+
+	fn merge(&mut self, other: &Self) {
+		if other.deleted {
+			self.deleted = true;
+			self.blocks.clear();
+		} else if !self.deleted {
+			for bi in other.blocks.iter() {
+				match self.blocks.binary_search_by(|x| x.offset.cmp(&bi.offset)) {
+					Ok(_) => (),
+					Err(pos) => {
+						self.blocks.insert(pos, bi.clone());
+					}
+				}
+			}
+		}
+	}
+}
+
+pub struct VersionTable {
+	pub background: Arc<BackgroundRunner>,
+	pub block_ref_table: Arc<Table<BlockRefTable, TableShardedReplication>>,
+}
+
+#[async_trait]
+impl TableSchema for VersionTable {
+	type P = Hash;
+	type S = EmptyKey;
+	type E = Version;
+	type Filter = ();
+
+	async fn updated(&self, old: Option<Self::E>, new: Option<Self::E>) -> Result<(), Error> {
+		let block_ref_table = self.block_ref_table.clone();
+		if let (Some(old_v), Some(new_v)) = (old, new) {
+			// Propagate deletion of version blocks
+			if new_v.deleted && !old_v.deleted {
+				let deleted_block_refs = old_v
+					.blocks
+					.iter()
+					.map(|vb| BlockRef {
+						block: vb.hash,
+						version: old_v.uuid,
+						deleted: true,
+					})
+					.collect::<Vec<_>>();
+				block_ref_table.insert_many(&deleted_block_refs[..]).await?;
+			}
+		}
+		Ok(())
+	}
+
+	fn matches_filter(entry: &Self::E, _filter: &Self::Filter) -> bool {
+		!entry.deleted
+	}
+}