zcash_client_sqlite: Return a backend-specific Account type from ge…

…t_account_by_ufvk.

zcash_client_backend/CHANGELOG.md

@@ -13,6 +13,7 @@ and this library adheres to Rust's notion of
   changes related to `Orchard` below are introduced under this feature
   flag.
 - `zcash_client_backend::data_api`:
+  - `Account`
   - `AccountBalance::with_orchard_balance_mut`
   - `AccountBirthday::orchard_frontier`
   - `BlockMetadata::orchard_tree_size`
@@ -48,7 +49,10 @@ and this library adheres to Rust's notion of
   - Arguments to `BlockMetadata::from_parts` have changed.
   - Arguments to `ScannedBlock::from_parts` have changed.
   - Changes to the `WalletRead` trait:
+    - Added `Account` associated type.
     - Added `get_orchard_nullifiers`
+    - `get_account_for_ufvk` now returns an `Self::Account` instead of a bare
+      `AccountId`
   - Changes to the `InputSource` trait:
     - `select_spendable_notes` now takes its `target_value` argument as a
       `NonNegativeAmount`. Also, the values of the returned map are also

zcash_client_backend/src/data_api.rs

@@ -308,6 +308,35 @@ impl AccountBalance {
     }
 }
 
+/// A set of capabilities that a client account must provide.
+pub trait Account<AccountId: Copy> {
+    /// Returns the unique identifier for the account.
+    fn id(&self) -> AccountId;
+
+    /// Returns the UFVK that the wallet backend has stored for the account, if any.
+    fn ufvk(&self) -> Option<&UnifiedFullViewingKey>;
+}
+
+impl<A: Copy> Account<A> for (A, UnifiedFullViewingKey) {
+    fn id(&self) -> A {
+        self.0
+    }
+
+    fn ufvk(&self) -> Option<&UnifiedFullViewingKey> {
+        Some(&self.1)
+    }
+}
+
+impl<A: Copy> Account<A> for (A, Option<UnifiedFullViewingKey>) {
+    fn id(&self) -> A {
+        self.0
+    }
+
+    fn ufvk(&self) -> Option<&UnifiedFullViewingKey> {
+        self.1.as_ref()
+    }
+}
+
 /// A polymorphic ratio type, usually used for rational numbers.
 #[derive(Clone, Copy, Debug, PartialEq, Eq)]
 pub struct Ratio<T> {
@@ -492,6 +521,9 @@ pub trait WalletRead {
     /// will be interpreted as belonging to that account.
     type AccountId: Copy + Debug + Eq + Hash;
 
+    /// The concrete account type used by this wallet backend.
+    type Account: Account<Self::AccountId>;
+
     /// Verifies that the given seed corresponds to the viewing key for the specified account.
     ///
     /// Returns:
@@ -602,11 +634,11 @@ pub trait WalletRead {
         &self,
     ) -> Result<HashMap<Self::AccountId, UnifiedFullViewingKey>, Self::Error>;
 
-    /// Returns the account id corresponding to a given [`UnifiedFullViewingKey`], if any.
+    /// Returns the account corresponding to a given [`UnifiedFullViewingKey`], if any.
     fn get_account_for_ufvk(
         &self,
         ufvk: &UnifiedFullViewingKey,
-    ) -> Result<Option<Self::AccountId>, Self::Error>;
+    ) -> Result<Option<Self::Account>, Self::Error>;
 
     /// Returns the wallet balances and sync status for an account given the specified minimum
     /// number of confirmations, or `Ok(None)` if the wallet has no balance data available.
@@ -1438,6 +1470,7 @@ pub mod testing {
     impl WalletRead for MockWalletDb {
         type Error = ();
         type AccountId = u32;
+        type Account = (Self::AccountId, UnifiedFullViewingKey);
 
         fn validate_seed(
             &self,
@@ -1523,7 +1556,7 @@ pub mod testing {
         fn get_account_for_ufvk(
             &self,
             _ufvk: &UnifiedFullViewingKey,
-        ) -> Result<Option<Self::AccountId>, Self::Error> {
+        ) -> Result<Option<Self::Account>, Self::Error> {
             Ok(None)
         }
 

zcash_client_backend/src/data_api/wallet.rs

@@ -45,8 +45,8 @@ use super::InputSource;
 use crate::{
     address::Address,
     data_api::{
-        error::Error, SentTransaction, SentTransactionOutput, WalletCommitmentTrees, WalletRead,
-        WalletWrite,
+        error::Error, Account, SentTransaction, SentTransactionOutput, WalletCommitmentTrees,
+        WalletRead, WalletWrite,
     },
     decrypt_transaction,
     fees::{self, DustOutputPolicy},
@@ -269,7 +269,7 @@ where
         wallet_db,
         params,
         StandardFeeRule::PreZip313,
-        account,
+        account.id(),
         min_confirmations,
         to,
         amount,
@@ -380,7 +380,7 @@ where
     let proposal = propose_transfer(
         wallet_db,
         params,
-        account,
+        account.id(),
         input_selector,
         request,
         min_confirmations,
@@ -694,7 +694,8 @@ where
     let account = wallet_db
         .get_account_for_ufvk(&usk.to_unified_full_viewing_key())
         .map_err(Error::DataSource)?
-        .ok_or(Error::KeyNotRecognized)?;
+        .ok_or(Error::KeyNotRecognized)?
+        .id();
 
     let (sapling_anchor, sapling_inputs) =
         if proposal_step.involves(PoolType::Shielded(ShieldedProtocol::Sapling)) {

zcash_client_sqlite/src/lib.rs

@@ -256,6 +256,7 @@ impl<C: Borrow<rusqlite::Connection>, P: consensus::Parameters> InputSource for
 impl<C: Borrow<rusqlite::Connection>, P: consensus::Parameters> WalletRead for WalletDb<C, P> {
     type Error = SqliteClientError;
     type AccountId = AccountId;
+    type Account = (AccountId, Option<UnifiedFullViewingKey>);
 
     fn validate_seed(
         &self,
@@ -373,8 +374,8 @@ impl<C: Borrow<rusqlite::Connection>, P: consensus::Parameters> WalletRead for W
     fn get_account_for_ufvk(
         &self,
         ufvk: &UnifiedFullViewingKey,
-    ) -> Result<Option<AccountId>, Self::Error> {
-        wallet::get_account_for_ufvk(self.conn.borrow(), ufvk)
+    ) -> Result<Option<Self::Account>, Self::Error> {
+        wallet::get_account_for_ufvk(self.conn.borrow(), &self.params, ufvk)
     }
 
     fn get_wallet_summary(

zcash_client_sqlite/src/wallet.rs

@@ -693,31 +693,46 @@ pub(crate) fn get_unified_full_viewing_keys<P: consensus::Parameters>(
 
 /// Returns the account id corresponding to a given [`UnifiedFullViewingKey`],
 /// if any.
-pub(crate) fn get_account_for_ufvk(
+pub(crate) fn get_account_for_ufvk<P: consensus::Parameters>(
     conn: &rusqlite::Connection,
+    params: &P,
     ufvk: &UnifiedFullViewingKey,
-) -> Result<Option<AccountId>, SqliteClientError> {
+) -> Result<Option<(AccountId, Option<UnifiedFullViewingKey>)>, SqliteClientError> {
     #[cfg(feature = "transparent-inputs")]
     let transparent_item = ufvk.transparent().map(|k| k.serialize());
     #[cfg(not(feature = "transparent-inputs"))]
     let transparent_item: Option<Vec<u8>> = None;
 
     let mut stmt = conn.prepare(
-        "SELECT id
+        "SELECT id, ufvk
         FROM accounts
         WHERE orchard_fvk_item_cache = :orchard_fvk_item_cache
            OR sapling_fvk_item_cache = :sapling_fvk_item_cache
            OR p2pkh_fvk_item_cache = :p2pkh_fvk_item_cache",
     )?;
 
     let accounts = stmt
-        .query_and_then::<_, rusqlite::Error, _, _>(
+        .query_and_then::<_, SqliteClientError, _, _>(
             named_params![
                 ":orchard_fvk_item_cache": ufvk.orchard().map(|k| k.to_bytes()),
                 ":sapling_fvk_item_cache": ufvk.sapling().map(|k| k.to_bytes()),
                 ":p2pkh_fvk_item_cache": transparent_item,
             ],
-            |row| row.get::<_, u32>(0).map(AccountId),
+            |row| {
+                let account_id = row.get::<_, u32>(0).map(AccountId)?;
+                Ok((
+                    account_id,
+                    row.get::<_, Option<String>>(1)?
+                        .map(|ufvk_str| UnifiedFullViewingKey::decode(params, &ufvk_str))
+                        .transpose()
+                        .map_err(|e| {
+                            SqliteClientError::CorruptedData(format!(
+                                "Could not decode unified full viewing key for account {:?}: {}",
+                                account_id, e
+                            ))
+                        })?,
+                ))
+            },
         )?
         .collect::<Result<Vec<_>, _>>()?;
 
@@ -726,7 +741,7 @@ pub(crate) fn get_account_for_ufvk(
             "Mutiple account records correspond to a single UFVK".to_owned(),
         ))
     } else {
-        Ok(accounts.first().copied())
+        Ok(accounts.into_iter().next())
     }
 }