tx_graph: maintain v1 ChangeSet

Author: ValuedMammal

crates/chain/src/rusqlite_impl.rs

@@ -199,8 +199,8 @@ fn to_sql_error<E: std::error::Error + Send + Sync + 'static>(err: E) -> rusqlit
     rusqlite::Error::ToSqlConversionFailure(Box::new(err))
 }
 
-impl tx_graph::ChangeSet<ConfirmationBlockTime> {
-    /// Schema name for [`tx_graph::ChangeSet`].
+impl tx_graph::v1::ChangeSet<ConfirmationBlockTime> {
+    /// Schema name for [`tx_graph::v1::ChangeSet`].
     pub const SCHEMA_NAME: &'static str = "bdk_txgraph";
     /// Name of table that stores full transactions and `last_seen` timestamps.
     pub const TXS_TABLE_NAME: &'static str = "bdk_txs";
@@ -209,7 +209,7 @@ impl tx_graph::ChangeSet<ConfirmationBlockTime> {
     /// Name of table that stores [`Anchor`]s.
     pub const ANCHORS_TABLE_NAME: &'static str = "bdk_anchors";
 
-    /// Get v0 of sqlite [tx_graph::ChangeSet] schema
+    /// Get v0 of sqlite [tx_graph::v1::ChangeSet] schema
     pub fn schema_v0() -> String {
         // full transactions
         let create_txs_table = format!(
@@ -247,7 +247,7 @@ impl tx_graph::ChangeSet<ConfirmationBlockTime> {
         format!("{create_txs_table}; {create_txouts_table}; {create_anchors_table}")
     }
 
-    /// Get v1 of sqlite [tx_graph::ChangeSet] schema
+    /// Get v1 of sqlite [tx_graph::v1::ChangeSet] schema
     pub fn schema_v1() -> String {
         let add_confirmation_time_column = format!(
             "ALTER TABLE {} ADD COLUMN confirmation_time INTEGER DEFAULT -1 NOT NULL",
@@ -567,7 +567,7 @@ mod test {
 
     #[test]
     fn can_persist_anchors_and_txs_independently() -> anyhow::Result<()> {
-        type ChangeSet = tx_graph::ChangeSet<ConfirmationBlockTime>;
+        type ChangeSet = tx_graph::v1::ChangeSet<ConfirmationBlockTime>;
         let mut conn = rusqlite::Connection::open_in_memory()?;
 
         // init tables
@@ -629,7 +629,7 @@ mod test {
 
     #[test]
     fn v0_to_v1_schema_migration_is_backward_compatible() -> anyhow::Result<()> {
-        type ChangeSet = tx_graph::ChangeSet<ConfirmationBlockTime>;
+        type ChangeSet = tx_graph::v1::ChangeSet<ConfirmationBlockTime>;
         let mut conn = rusqlite::Connection::open_in_memory()?;
 
         // Create initial database with v0 sqlite schema

crates/chain/src/tx_graph.rs

@@ -119,6 +119,9 @@ use core::{
     ops::{Deref, RangeInclusive},
 };
 
+mod changeset;
+pub use changeset::v1;
+
 impl<A: Ord, X> From<TxGraph<A, X>> for TxUpdate<A> {
     fn from(graph: TxGraph<A, X>) -> Self {
         Self {
@@ -1450,6 +1453,18 @@ impl<A, X> From<X> for ChangeSet<A, X> {
     }
 }
 
+impl<A> From<v1::ChangeSet<A>> for ChangeSet<A> {
+    fn from(cs: v1::ChangeSet<A>) -> Self {
+        Self {
+            txs: cs.txs,
+            txouts: cs.txouts,
+            anchors: cs.anchors,
+            last_seen: cs.last_seen,
+            indexer: (),
+        }
+    }
+}
+
 impl<A, X> ChangeSet<A, X> {
     /// Iterates over all outpoints contained within [`ChangeSet`].
     pub fn txouts(&self) -> impl Iterator<Item = (OutPoint, &TxOut)> {
@@ -1482,6 +1497,19 @@ impl<A, X> ChangeSet<A, X> {
                 !duplicate
             })
     }
+
+    /// Downgrade this changeset to [`v1`] and return a tuple that includes the `indexer` changes.
+    pub fn to_v1(self) -> (v1::ChangeSet<A>, X) {
+        (
+            v1::ChangeSet {
+                txs: self.txs,
+                txouts: self.txouts,
+                anchors: self.anchors,
+                last_seen: self.last_seen,
+            },
+            self.indexer,
+        )
+    }
 }
 
 impl<A: Ord, X: Merge> Merge for ChangeSet<A, X> {

crates/chain/src/tx_graph/changeset.rs

@@ -0,0 +1,77 @@
+use alloc::sync::Arc;
+use alloc::vec::Vec;
+
+use bitcoin::{OutPoint, Transaction, TxOut, Txid};
+
+use crate::collections::{BTreeMap, BTreeSet};
+use crate::Merge;
+
+/// Version 1 [`ChangeSet`](v1::ChangeSet)
+pub mod v1 {
+    use super::*;
+
+    /// The [`ChangeSet`] represents changes to a [`TxGraph`].
+    ///
+    /// Since [`TxGraph`] is monotone, the "changeset" can only contain transactions to be added and
+    /// not removed.
+    ///
+    /// Refer to the [module-level documentation](crate::tx_graph) for more.
+    ///
+    /// [`TxGraph`]: crate::TxGraph
+    #[derive(Debug, Clone, PartialEq)]
+    #[cfg_attr(
+        feature = "serde",
+        derive(serde::Deserialize, serde::Serialize),
+        serde(bound(
+            deserialize = "A: Ord + serde::Deserialize<'de>",
+            serialize = "A: Ord + serde::Serialize",
+        ))
+    )]
+    pub struct ChangeSet<A = ()> {
+        /// Added transactions.
+        pub txs: BTreeSet<Arc<Transaction>>,
+        /// Added txouts.
+        pub txouts: BTreeMap<OutPoint, TxOut>,
+        /// Added anchors.
+        pub anchors: BTreeSet<(A, Txid)>,
+        /// Added last-seen unix timestamps of transactions.
+        pub last_seen: BTreeMap<Txid, u64>,
+    }
+
+    impl<A> Default for ChangeSet<A> {
+        fn default() -> Self {
+            Self {
+                txs: Default::default(),
+                txouts: Default::default(),
+                anchors: Default::default(),
+                last_seen: Default::default(),
+            }
+        }
+    }
+
+    impl<A: Ord> Merge for ChangeSet<A> {
+        fn merge(&mut self, other: Self) {
+            // We use `extend` instead of `BTreeMap::append` due to performance issues with `append`.
+            // Refer to https://github.com/rust-lang/rust/issues/34666#issuecomment-675658420
+            self.txs.extend(other.txs);
+            self.txouts.extend(other.txouts);
+            self.anchors.extend(other.anchors);
+
+            // last_seen timestamps should only increase
+            self.last_seen.extend(
+                other
+                    .last_seen
+                    .into_iter()
+                    .filter(|(txid, update_ls)| self.last_seen.get(txid) < Some(update_ls))
+                    .collect::<Vec<_>>(),
+            );
+        }
+
+        fn is_empty(&self) -> bool {
+            self.txs.is_empty()
+                && self.txouts.is_empty()
+                && self.anchors.is_empty()
+                && self.last_seen.is_empty()
+        }
+    }
+}

crates/wallet/src/wallet/changeset.rs

@@ -13,10 +13,7 @@ pub struct ChangeSet {
     /// Changes to the [`LocalChain`](local_chain::LocalChain).
     pub local_chain: local_chain::ChangeSet,
     /// Changes to [`TxGraph`](tx_graph::TxGraph).
-    ///
-    /// The `indexer` field of this changeset can be ignored, as it is always the unit
-    /// type. The actual [`Self::indexer`] changeset is managed separately.
-    pub tx_graph: tx_graph::ChangeSet<ConfirmationBlockTime>,
+    pub tx_graph: tx_graph::v1::ChangeSet<ConfirmationBlockTime>,
     /// Changes to [`KeychainTxOutIndex`](keychain_txout::KeychainTxOutIndex).
     pub indexer: keychain_txout::ChangeSet,
 }
@@ -90,9 +87,9 @@ impl ChangeSet {
             &[&Self::schema_v0()],
         )?;
 
-        bdk_chain::local_chain::ChangeSet::init_sqlite_tables(db_tx)?;
-        bdk_chain::tx_graph::ChangeSet::<ConfirmationBlockTime>::init_sqlite_tables(db_tx)?;
-        bdk_chain::keychain_txout::ChangeSet::init_sqlite_tables(db_tx)?;
+        local_chain::ChangeSet::init_sqlite_tables(db_tx)?;
+        tx_graph::v1::ChangeSet::<ConfirmationBlockTime>::init_sqlite_tables(db_tx)?;
+        keychain_txout::ChangeSet::init_sqlite_tables(db_tx)?;
 
         Ok(())
     }
@@ -126,7 +123,7 @@ impl ChangeSet {
         }
 
         changeset.local_chain = local_chain::ChangeSet::from_sqlite(db_tx)?;
-        changeset.tx_graph = tx_graph::ChangeSet::<_>::from_sqlite(db_tx)?;
+        changeset.tx_graph = tx_graph::v1::ChangeSet::<_>::from_sqlite(db_tx)?;
         changeset.indexer = keychain_txout::ChangeSet::from_sqlite(db_tx)?;
 
         Ok(changeset)
@@ -193,22 +190,17 @@ impl From<tx_graph::ChangeSet<ConfirmationBlockTime, keychain_txout::ChangeSet>>
     fn from(
         tx_graph: tx_graph::ChangeSet<ConfirmationBlockTime, keychain_txout::ChangeSet>,
     ) -> Self {
+        let (tx_graph, indexer) = tx_graph.to_v1();
         Self {
-            tx_graph: tx_graph::ChangeSet {
-                txs: tx_graph.txs,
-                txouts: tx_graph.txouts,
-                anchors: tx_graph.anchors,
-                last_seen: tx_graph.last_seen,
-                ..Default::default()
-            },
-            indexer: tx_graph.indexer,
+            tx_graph,
+            indexer,
             ..Default::default()
         }
     }
 }
 
-impl From<tx_graph::ChangeSet<ConfirmationBlockTime>> for ChangeSet {
-    fn from(tx_graph: tx_graph::ChangeSet<ConfirmationBlockTime>) -> Self {
+impl From<tx_graph::v1::ChangeSet<ConfirmationBlockTime>> for ChangeSet {
+    fn from(tx_graph: tx_graph::v1::ChangeSet<ConfirmationBlockTime>) -> Self {
         Self {
             tx_graph,
             ..Default::default()

crates/wallet/src/wallet/mod.rs

@@ -600,7 +600,7 @@ impl Wallet {
         index.apply_changeset(changeset.indexer);
 
         let mut graph = TxGraph::new(());
-        graph.apply_changeset(changeset.tx_graph);
+        graph.apply_changeset(changeset.tx_graph.into());
         let mut indexed_graph = graph.swap_indexer(index).0;
         let _ = indexed_graph.reindex();