clear storage based on provided history depth

Signed-off-by: Uncle Stinky <uncle.stinky@ghostchain.io>

pallets/slow-clap/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "ghost-slow-clap"
-version = "0.3.24"
+version = "0.3.25"
 description = "Applause protocol for the EVM bridge"
 license.workspace = true
 authors.workspace = true

pallets/slow-clap/src/lib.rs

@@ -299,6 +299,9 @@ pub mod pallet {
         #[pallet::constant]
         type UnsignedPriority: Get<TransactionPriority>;
 
+        #[pallet::constant]
+        type HistoryDepth: Get<SessionIndex>;
+
         type WeightInfo: WeightInfo;
     }
 
@@ -339,11 +342,11 @@ pub mod pallet {
     pub(super) type ReceivedClaps<T: Config> = StorageNMap<
         _,
         (
-            NMapKey<Twox64Concat, u32>,
+            NMapKey<Twox64Concat, SessionIndex>,
             NMapKey<Twox64Concat, H256>,
             NMapKey<Twox64Concat, H256>,
         ),
-        BoundedBTreeSet<u32, T::MaxAuthorities>,
+        BoundedBTreeSet<AuthIndex, T::MaxAuthorities>,
         ValueQuery
     >;
     
@@ -352,7 +355,7 @@ pub mod pallet {
     pub(super) type ApplausesForTransaction<T: Config> = StorageNMap<
         _,
         (
-            NMapKey<Twox64Concat, u32>,
+            NMapKey<Twox64Concat, SessionIndex>,
             NMapKey<Twox64Concat, H256>,
             NMapKey<Twox64Concat, H256>,
         ),
@@ -928,10 +931,23 @@ impl<T: Config> Pallet<T> {
         assert!(Authorities::<T>::get(&session_index).is_empty(), "Authorities are already initilized!");
         let bounded_authorities = WeakBoundedVec::<_, T::MaxAuthorities>::try_from(authorities)
             .expect("more than the maximum number of authorities");
+
+        if let Some(target_session_index) = session_index.checked_sub(T::HistoryDepth::get()) {
+            Self::clear_history(&target_session_index);
+        }
+
         Authorities::<T>::set(&session_index, bounded_authorities);
         ClapsInSession::<T>::set(&session_index, Default::default());
     }
 
+    fn clear_history(target_session_index: &SessionIndex) {
+        ClapsInSession::<T>::remove(target_session_index);
+        let mut cursor = ReceivedClaps::<T>::clear_prefix((target_session_index,), u32::MAX, None);
+        debug_assert!(cursor.maybe_cursor.is_none());
+        cursor = ApplausesForTransaction::<T>::clear_prefix((target_session_index,), u32::MAX, None);
+        debug_assert!(cursor.maybe_cursor.is_none());
+    }
+
     fn calculate_median_claps(session_index: &SessionIndex) -> u32 {
         let mut claps_in_session = ClapsInSession::<T>::get(session_index)
             .values()

pallets/slow-clap/src/mock.rs

@@ -187,6 +187,7 @@ pallet_staking_reward_curve::build! {
 parameter_types! {
     pub static ExistentialDeposit: u64 = 2;
     pub const RewardCurve: &'static PiecewiseLinear<'static> = &REWARD_CURVE;
+    pub const HistoryDepth: u32 = 10;
 }
 
 #[derive_impl(pallet_balances::config_preludes::TestDefaultConfig)]
@@ -212,6 +213,7 @@ impl Config for Runtime {
     type ApplauseThreshold = ConstU32<50>;
     type OffenceThreshold = ConstU32<75>;
     type UnsignedPriority = ConstU64<{ 1 << 20 }>;
+    type HistoryDepth = HistoryDepth;
 
     type WeightInfo = ();
 }

pallets/slow-clap/src/tests.rs

@@ -247,6 +247,35 @@ fn should_make_http_call_and_parse_logs() {
     });
 }
 
+#[test]
+fn should_clear_sesions_based_on_history_depth() {
+    let (network_id, transaction_hash, unique_transaction_hash) =
+        generate_unique_hash(None, None, None, None);
+
+    new_test_ext().execute_with(|| {
+        let session_index = advance_session_and_get_index();
+        let history_depth = HistoryDepth::get();
+        let storage_key = (session_index, transaction_hash, unique_transaction_hash);
+
+        assert_claps_info_correct(&storage_key, &session_index, 0);
+        assert_eq!(pallet::ApplausesForTransaction::<Runtime>::get(&storage_key), false);
+
+        assert_ok!(do_clap_from(session_index, network_id, 0, false));
+        assert_ok!(do_clap_from(session_index, network_id, 1, false));
+        assert_ok!(do_clap_from(session_index, network_id, 2, false));
+
+        assert_claps_info_correct(&storage_key, &session_index, 3);
+        assert_eq!(pallet::ApplausesForTransaction::<Runtime>::get(&storage_key), true);
+
+        for _ in 0..history_depth {
+            advance_session();
+        }
+
+        assert_claps_info_correct(&storage_key, &session_index, 0);
+        assert_eq!(pallet::ApplausesForTransaction::<Runtime>::get(&storage_key), false);
+    });
+}
+
 #[test]
 fn should_collect_commission_accordingly() {
     let (network_id, _, _) = generate_unique_hash(None, None, None, None);