feat(mint): add get blinded_sig by keyset

CHANGELOG.md

@@ -41,6 +41,7 @@
 - cdk-cli(receive): Add support for signing keys to be nostr nsec encoded ([thesimplekid]).
 - cdk-fake-wallet: Add Fake wallet for testing ([thesimplekid]).
 - cdk(cdk-database/mint): Add `add_proofs`, `get_proofs_by_ys`, `get_proofs_states`, and `update_proofs_states` ([thesimplekid]).
+- cdk(cdk-database/mint): Add `get_blinded_signatures_for_keyset` to get all blind signatures for a `keyset_id` ([thesimplekid]).
 
 ### Fixed
 - cdk(mint): `SIG_ALL` is not allowed in `melt` ([thesimplekid]).

crates/cdk-redb/src/mint/mod.rs

@@ -670,4 +670,27 @@ impl MintDatabase for MintRedbDatabase {
 
         Ok(signatures)
     }
+
+    async fn get_blinded_signatures_for_keyset(
+        &self,
+        keyset_id: &Id,
+    ) -> Result<Vec<BlindSignature>, Self::Err> {
+        let db = self.db.lock().await;
+        let read_txn = db.begin_read().map_err(Error::from)?;
+        let table = read_txn
+            .open_table(BLINDED_SIGNATURES)
+            .map_err(Error::from)?;
+
+        Ok(table
+            .iter()
+            .map_err(Error::from)?
+            .flatten()
+            .filter_map(|(_m, s)| {
+                match serde_json::from_str::<BlindSignature>(s.value()).ok() {
+                    Some(signature) if &signature.keyset_id == keyset_id => Some(signature), // Filter by keyset_id
+                    _ => None, // Exclude non-matching entries
+                }
+            })
+            .collect())
+    }
 }

crates/cdk-sqlite/src/mint/mod.rs

@@ -685,6 +685,30 @@ WHERE y=?;
 
         Ok(signatures)
     }
+
+    async fn get_blinded_signatures_for_keyset(
+        &self,
+        keyset_id: &Id,
+    ) -> Result<Vec<BlindSignature>, Self::Err> {
+        let rec = sqlx::query(
+            r#"
+SELECT *
+FROM blind_signature
+WHERE keyset_id=?;
+        "#,
+        )
+        .bind(keyset_id.to_string())
+        .fetch_all(&self.pool)
+        .await;
+
+        let signatures = rec
+            .map_err(Error::from)?
+            .into_iter()
+            .flat_map(sqlite_row_to_blind_signature)
+            .collect();
+
+        Ok(signatures)
+    }
 }
 
 fn sqlite_row_to_keyset_info(row: SqliteRow) -> Result<MintKeySetInfo, Error> {

crates/cdk/src/cdk_database/mint_memory.rs

@@ -303,4 +303,17 @@ impl MintDatabase for MintMemoryDatabase {
 
         Ok(signatures)
     }
+
+    async fn get_blinded_signatures_for_keyset(
+        &self,
+        keyset_id: &Id,
+    ) -> Result<Vec<BlindSignature>, Self::Err> {
+        let blinded_signatures = self.blinded_signatures.read().await;
+
+        Ok(blinded_signatures
+            .values()
+            .filter(|b| &b.keyset_id == keyset_id)
+            .cloned()
+            .collect())
+    }
 }

crates/cdk/src/cdk_database/mod.rs

@@ -237,4 +237,9 @@ pub trait MintDatabase {
         &self,
         blinded_messages: &[PublicKey],
     ) -> Result<Vec<Option<BlindSignature>>, Self::Err>;
+    /// Get [`BlindSignature`]s for keyset_id
+    async fn get_blinded_signatures_for_keyset(
+        &self,
+        keyset_id: &Id,
+    ) -> Result<Vec<BlindSignature>, Self::Err>;
 }