[wip] feat!: add wallet birthday

Author: luisschwab

src/persist_test_utils.rs

@@ -168,6 +168,7 @@ where
         descriptor: Some(descriptor.clone()),
         change_descriptor: Some(change_descriptor.clone()),
         network: Some(Network::Testnet),
+        birthday: None,
         local_chain: local_chain_changeset,
         tx_graph: tx_graph_changeset,
         indexer: keychain_txout_changeset,
@@ -227,6 +228,7 @@ where
         descriptor: None,
         change_descriptor: None,
         network: None,
+        birthday: None,
         local_chain: local_chain_changeset,
         tx_graph: tx_graph_changeset,
         indexer: keychain_txout_changeset,

src/wallet/changeset.rs

@@ -1,6 +1,7 @@
 use bdk_chain::{
     indexed_tx_graph, keychain_txout, local_chain, tx_graph, ConfirmationBlockTime, Merge,
 };
+use chain::BlockId;
 use miniscript::{Descriptor, DescriptorPublicKey};
 use serde::{Deserialize, Serialize};
 
@@ -110,6 +111,9 @@ pub struct ChangeSet {
     pub change_descriptor: Option<Descriptor<DescriptorPublicKey>>,
     /// Stores the network type of the transaction data.
     pub network: Option<bitcoin::Network>,
+    /// Stores the [`Wallet`]'s birthday, defined as the first [`Block`] which has relevant
+    /// transactions to this [`Wallet`].
+    pub birthday: Option<BlockId>,
     /// Changes to the [`LocalChain`](local_chain::LocalChain).
     pub local_chain: local_chain::ChangeSet,
     /// Changes to [`TxGraph`](tx_graph::TxGraph).
@@ -145,6 +149,14 @@ impl Merge for ChangeSet {
             );
             self.network = other.network;
         }
+        // TODO(@luisschwab): should merging [`ChangeSet`]s with distinct birthdays be possible?
+        if other.birthday.is_some() {
+            debug_assert!(
+                self.birthday.is_none() || self.birthday == other.birthday,
+                "birthday must never change"
+            );
+            self.birthday = other.birthday;
+        }
 
         // merge locked outpoints
         self.locked_outpoints.merge(other.locked_outpoints);
@@ -158,6 +170,7 @@ impl Merge for ChangeSet {
         self.descriptor.is_none()
             && self.change_descriptor.is_none()
             && self.network.is_none()
+            && self.birthday.is_none()
             && self.local_chain.is_empty()
             && self.tx_graph.is_empty()
             && self.indexer.is_empty()
@@ -174,14 +187,15 @@ impl ChangeSet {
     /// Name of table to store wallet locked outpoints.
     pub const WALLET_OUTPOINT_LOCK_TABLE_NAME: &'static str = "bdk_wallet_locked_outpoints";
 
-    /// Get v0 sqlite [ChangeSet] schema
+    /// Get v0 sqlite [`ChangeSet`] schema.
     pub fn schema_v0() -> alloc::string::String {
         format!(
             "CREATE TABLE {} ( \
                 id INTEGER PRIMARY KEY NOT NULL CHECK (id = 0), \
                 descriptor TEXT, \
                 change_descriptor TEXT, \
                 network TEXT \
+                birthday TEXT \
                 ) STRICT;",
             Self::WALLET_TABLE_NAME,
         )
@@ -223,7 +237,7 @@ impl ChangeSet {
         let mut changeset = Self::default();
 
         let mut wallet_statement = db_tx.prepare(&format!(
-            "SELECT descriptor, change_descriptor, network FROM {}",
+            "SELECT descriptor, change_descriptor, network, birthday FROM {}",
             Self::WALLET_TABLE_NAME,
         ))?;
         let row = wallet_statement
@@ -234,13 +248,16 @@ impl ChangeSet {
                         "change_descriptor",
                     )?,
                     row.get::<_, Option<Impl<bitcoin::Network>>>("network")?,
+                    // TODO(@luisschwab): implement `Impl FromSql` fot `BlockId` on bdk_chain
+                    row.get::<_, Option<Impl<BlockId>>>("birthday")?,
                 ))
             })
             .optional()?;
-        if let Some((desc, change_desc, network)) = row {
+        if let Some((desc, change_desc, network, birthday)) = row {
             changeset.descriptor = desc.map(Impl::into_inner);
             changeset.change_descriptor = change_desc.map(Impl::into_inner);
             changeset.network = network.map(Impl::into_inner);
+            changeset.birthday = birthday.map(Impl::into_inner);
         }
 
         // Select locked outpoints.
@@ -309,6 +326,17 @@ impl ChangeSet {
             })?;
         }
 
+        let mut birthday_statement = db_tx.prepare_cached(&format!(
+            "INSERT INTO {}(id, birthday) VALUES(:id, :birthday) ON CONFLICT(id) DO UPDATE SET birthday=:birthday",
+            Self::WALLET_TABLE_NAME,
+        ))?;
+        if let Some(birthday) = self.birthday {
+            birthday_statement.execute(named_params! {
+                ":id": 0,
+                ":birthday": Impl(birthday),
+            })?;
+        }
+
         // Insert or delete locked outpoints.
         let mut insert_stmt = db_tx.prepare_cached(&format!(
             "INSERT OR IGNORE INTO {}(txid, vout) VALUES(:txid, :vout)",

src/wallet/mod.rs

@@ -449,7 +449,12 @@ impl Wallet {
         let genesis_hash = params
             .genesis_hash
             .unwrap_or(genesis_block(network).block_hash());
-        let (chain, chain_changeset) = LocalChain::from_genesis_hash(genesis_hash);
+        let (mut chain, chain_changeset) = LocalChain::from_genesis_hash(genesis_hash);
+        if let Some(birthday) = params.birthday {
+            chain
+                .apply_update(CheckPoint::new(birthday))
+                .expect("wallet birthday overrided genesis hash");
+        }
 
         let (descriptor, mut descriptor_keymap) = (params.descriptor)(&secp, network_kind)?;
         check_wallet_descriptor(&descriptor)?;

src/wallet/params.rs

@@ -2,6 +2,7 @@ use alloc::boxed::Box;
 
 use bdk_chain::keychain_txout::DEFAULT_LOOKAHEAD;
 use bitcoin::{BlockHash, Network, NetworkKind};
+use chain::BlockId;
 use miniscript::descriptor::KeyMap;
 
 use crate::{
@@ -65,6 +66,7 @@ pub struct CreateParams {
     pub(crate) change_descriptor_keymap: KeyMap,
     pub(crate) network: Network,
     pub(crate) genesis_hash: Option<BlockHash>,
+    pub(crate) birthday: Option<BlockId>,
     pub(crate) lookahead: u32,
     pub(crate) use_spk_cache: bool,
 }
@@ -88,6 +90,7 @@ impl CreateParams {
             change_descriptor_keymap: KeyMap::default(),
             network: Network::Bitcoin,
             genesis_hash: None,
+            birthday: None,
             lookahead: DEFAULT_LOOKAHEAD,
             use_spk_cache: false,
         }
@@ -110,6 +113,7 @@ impl CreateParams {
             change_descriptor_keymap: KeyMap::default(),
             network: Network::Bitcoin,
             genesis_hash: None,
+            birthday: None,
             lookahead: DEFAULT_LOOKAHEAD,
             use_spk_cache: false,
         }
@@ -135,6 +139,7 @@ impl CreateParams {
             change_descriptor_keymap: KeyMap::default(),
             network: Network::Bitcoin,
             genesis_hash: None,
+            birthday: None,
             lookahead: DEFAULT_LOOKAHEAD,
             use_spk_cache: false,
         }
@@ -162,6 +167,15 @@ impl CreateParams {
         self
     }
 
+    /// Set the [`Wallet`]'s birthday, as a [`BlockId`].
+    ///
+    /// The birthday can be used to limit how far back a chain oracle is queried,
+    /// saving up time and data bandwidth in full-scans.
+    pub fn birthday(mut self, birthday: BlockId) -> Self {
+        self.birthday = Some(birthday);
+        self
+    }
+
     /// Use a custom `lookahead` value.
     ///
     /// The `lookahead` defines a number of script pubkeys to derive over and above the last
@@ -218,6 +232,7 @@ pub struct LoadParams {
     pub(crate) lookahead: u32,
     pub(crate) check_network: Option<Network>,
     pub(crate) check_genesis_hash: Option<BlockHash>,
+    pub(crate) check_birthday: Option<BlockId>,
     pub(crate) check_descriptor: Option<Option<DescriptorToExtract>>,
     pub(crate) check_change_descriptor: Option<Option<DescriptorToExtract>>,
     pub(crate) extract_keys: bool,
@@ -235,6 +250,7 @@ impl LoadParams {
             lookahead: DEFAULT_LOOKAHEAD,
             check_network: None,
             check_genesis_hash: None,
+            check_birthday: None,
             check_descriptor: None,
             check_change_descriptor: None,
             extract_keys: false,
@@ -282,6 +298,12 @@ impl LoadParams {
         self
     }
 
+    /// Checks that the given `birthday` matches the one loaded from persistence.
+    pub fn check_birthday(mut self, birthday: BlockId) -> Self {
+        self.check_birthday = Some(birthday);
+        self
+    }
+
     /// Use a custom `lookahead` value.
     ///
     /// The `lookahead` defines a number of script pubkeys to derive over and above the last