[Feature] StakeTracker P1 - VotersList

Cargo.toml

@@ -139,6 +139,7 @@ members = [
 	"frame/session/benchmarking",
 	"frame/society",
 	"frame/staking",
+	"frame/stake-tracker",
 	"frame/staking/reward-curve",
 	"frame/staking/reward-fn",
 	"frame/state-trie-migration",

bin/node/runtime/Cargo.toml

@@ -95,6 +95,7 @@ pallet-root-testing = { version = "1.0.0-dev", default-features = false, path =
 pallet-session = { version = "4.0.0-dev", features = [ "historical" ], path = "../../../frame/session", default-features = false }
 pallet-session-benchmarking = { version = "4.0.0-dev", path = "../../../frame/session/benchmarking", default-features = false, optional = true }
 pallet-staking = { version = "4.0.0-dev", default-features = false, path = "../../../frame/staking" }
+pallet-stake-tracker = { version = "4.0.0-dev", default-features = false, path = "../../../frame/stake-tracker" }
 pallet-staking-reward-curve = { version = "4.0.0-dev", default-features = false, path = "../../../frame/staking/reward-curve" }
 pallet-state-trie-migration = { version = "4.0.0-dev", default-features = false, path = "../../../frame/state-trie-migration" }
 pallet-scheduler = { version = "4.0.0-dev", default-features = false, path = "../../../frame/scheduler" }
@@ -174,6 +175,7 @@ std = [
 	"sp-runtime/std",
 	"sp-staking/std",
 	"pallet-staking/std",
+	"pallet-stake-tracker/std",
 	"pallet-state-trie-migration/std",
 	"sp-session/std",
 	"pallet-sudo/std",
@@ -303,6 +305,7 @@ try-runtime = [
 	"pallet-root-testing/try-runtime",
 	"pallet-session/try-runtime",
 	"pallet-staking/try-runtime",
+	"pallet-stake-tracker/try-runtime",
 	"pallet-state-trie-migration/try-runtime",
 	"pallet-scheduler/try-runtime",
 	"pallet-society/try-runtime",

bin/node/runtime/src/lib.rs

@@ -578,14 +578,21 @@ impl pallet_staking::Config for Runtime {
 	type OffendingValidatorsThreshold = OffendingValidatorsThreshold;
 	type ElectionProvider = ElectionProviderMultiPhase;
 	type GenesisElectionProvider = onchain::OnChainExecution<OnChainSeqPhragmen>;
-	type VoterList = VoterList;
+	type VoterList = <Runtime as pallet_stake_tracker::Config>::VoterList;
 	// This a placeholder, to be introduced in the next PR as an instance of bags-list
 	type TargetList = pallet_staking::UseValidatorsMap<Self>;
 	type MaxUnlockingChunks = ConstU32<32>;
 	type HistoryDepth = HistoryDepth;
 	type OnStakerSlash = NominationPools;
 	type WeightInfo = pallet_staking::weights::SubstrateWeight<Runtime>;
 	type BenchmarkingConfig = StakingBenchmarkingConfig;
+	type EventListener = StakeTracker;
+}
+
+impl pallet_stake_tracker::Config for Runtime {
+	type Currency = Balances;
+	type Staking = Staking;
+	type VoterList = VoterList;
 }
 
 impl pallet_fast_unstake::Config for Runtime {
@@ -1710,6 +1717,7 @@ construct_runtime!(
 		AssetTxPayment: pallet_asset_tx_payment,
 		ElectionProviderMultiPhase: pallet_election_provider_multi_phase,
 		Staking: pallet_staking,
+		StakeTracker: pallet_stake_tracker,
 		Session: pallet_session,
 		Democracy: pallet_democracy,
 		Council: pallet_collective::<Instance1>,

frame/babe/src/mock.rs

@@ -211,6 +211,7 @@ impl pallet_staking::Config for Test {
 	type OnStakerSlash = ();
 	type BenchmarkingConfig = pallet_staking::TestBenchmarkingConfig;
 	type WeightInfo = ();
+	type EventListener = ();
 }
 
 impl pallet_offences::Config for Test {

frame/bags-list/fuzzer/src/main.rs

@@ -27,7 +27,7 @@
 //! More information about `honggfuzz` can be found
 //! [here](https://docs.rs/honggfuzz/).
 
-use frame_election_provider_support::{SortedListProvider, VoteWeight};
+use frame_election_provider_support::{ReadOnlySortedListProvider, SortedListProvider, VoteWeight};
 use honggfuzz::fuzz;
 use pallet_bags_list::mock::{AccountId, BagsList, ExtBuilder};
 

frame/bags-list/remote-tests/Cargo.toml

@@ -15,6 +15,7 @@ targets = ["x86_64-unknown-linux-gnu"]
 [dependencies]
 # frame
 pallet-staking = { path = "../../staking", version = "4.0.0-dev" }
+pallet-stake-tracker = { path = "../../stake-tracker", version = "4.0.0-dev" }
 pallet-bags-list = { path = "../../bags-list", version = "4.0.0-dev" }
 frame-election-provider-support = { path = "../../election-provider-support", version = "4.0.0-dev" }
 frame-system = { path = "../../system", version = "4.0.0-dev" }

frame/bags-list/remote-tests/src/lib.rs

@@ -17,7 +17,7 @@
 
 //! Utilities for remote-testing pallet-bags-list.
 
-use frame_election_provider_support::ScoreProvider;
+use frame_election_provider_support::{ReadOnlySortedListProvider, ScoreProvider};
 use pallet_bags_list::Instance1;
 use sp_std::prelude::*;
 
@@ -32,12 +32,18 @@ pub mod try_state;
 ///
 /// For example, this can be the `Runtime` type of the Polkadot runtime.
 pub trait RuntimeT<I: 'static>:
-	pallet_staking::Config + pallet_bags_list::Config<I> + frame_system::Config
+	pallet_staking::Config
+	+ pallet_stake_tracker::Config
+	+ pallet_bags_list::Config<I>
+	+ frame_system::Config
 {
 }
 impl<
 		I: 'static,
-		T: pallet_staking::Config + pallet_bags_list::Config<I> + frame_system::Config,
+		T: pallet_staking::Config
+			+ pallet_stake_tracker::Config
+			+ pallet_bags_list::Config<I>
+			+ frame_system::Config,
 	> RuntimeT<I> for T
 {
 }
@@ -51,7 +57,6 @@ pub fn display_and_check_bags<Runtime: RuntimeT<Instance1>>(
 	currency_unit: u64,
 	currency_name: &'static str,
 ) {
-	use frame_election_provider_support::SortedListProvider;
 	use frame_support::traits::Get;
 
 	let min_nominator_bond = <pallet_staking::MinNominatorBond<Runtime>>::get();

frame/bags-list/remote-tests/src/migration.rs

@@ -17,6 +17,7 @@
 //! Test to check the migration of the voter bag.
 
 use crate::{RuntimeT, LOG_TARGET};
+use frame_election_provider_support::ReadOnlySortedListProvider;
 use frame_support::traits::PalletInfoAccess;
 use pallet_staking::Nominators;
 use remote_externalities::{Builder, Mode, OnlineConfig};
@@ -50,7 +51,7 @@ pub async fn execute<Runtime, Block>(
 
 		use frame_election_provider_support::SortedListProvider;
 		// run the actual migration
-		let moved = <Runtime as pallet_staking::Config>::VoterList::unsafe_regenerate(
+		let moved = <Runtime as pallet_stake_tracker::Config>::VoterList::unsafe_regenerate(
 			pallet_staking::Nominators::<Runtime>::iter().map(|(n, _)| n),
 			pallet_staking::Pallet::<Runtime>::weight_of_fn(),
 		);

frame/bags-list/remote-tests/src/snapshot.rs

@@ -16,7 +16,7 @@
 
 //! Test to execute the snapshot using the voter bag.
 
-use frame_election_provider_support::SortedListProvider;
+use frame_election_provider_support::ReadOnlySortedListProvider;
 use frame_support::traits::PalletInfoAccess;
 use remote_externalities::{Builder, Mode, OnlineConfig};
 use sp_runtime::{traits::Block as BlockT, DeserializeOwned};

frame/bags-list/remote-tests/src/try_state.rs

@@ -16,7 +16,7 @@
 
 //! Test to execute the sanity-check of the voter bag.
 
-use frame_election_provider_support::SortedListProvider;
+use frame_election_provider_support::ReadOnlySortedListProvider;
 use frame_support::{
 	storage::generator::StorageMap,
 	traits::{Get, PalletInfoAccess},

frame/bags-list/src/lib.rs

@@ -20,7 +20,7 @@
 //! A semi-sorted list, where items hold an `AccountId` based on some `Score`. The
 //! `AccountId` (`id` for short) might be synonym to a `voter` or `nominator` in some context, and
 //! `Score` signifies the chance of each id being included in the final
-//! [`SortedListProvider::iter`].
+//! [`ReadOnlySortedListProvider::iter`].
 //!
 //! It implements [`frame_election_provider_support::SortedListProvider`] to provide a semi-sorted
 //! list of accounts to another pallet. It needs some other pallet to give it some information about
@@ -54,7 +54,9 @@
 #![cfg_attr(not(feature = "std"), no_std)]
 
 use codec::FullCodec;
-use frame_election_provider_support::{ScoreProvider, SortedListProvider};
+use frame_election_provider_support::{
+	ReadOnlySortedListProvider, ScoreProvider, SortedListProvider,
+};
 use frame_system::ensure_signed;
 use sp_runtime::traits::{AtLeast32BitUnsigned, Bounded, StaticLookup};
 use sp_std::prelude::*;
@@ -269,7 +271,7 @@ pub mod pallet {
 
 		#[cfg(feature = "try-runtime")]
 		fn try_state(_: BlockNumberFor<T>) -> Result<(), &'static str> {
-			<Self as SortedListProvider<T::AccountId>>::try_state()
+			<Self as ReadOnlySortedListProvider<T::AccountId>>::try_state()
 		}
 	}
 }
@@ -299,7 +301,7 @@ impl<T: Config<I>, I: 'static> Pallet<T, I> {
 	}
 }
 
-impl<T: Config<I>, I: 'static> SortedListProvider<T::AccountId> for Pallet<T, I> {
+impl<T: Config<I>, I: 'static> ReadOnlySortedListProvider<T::AccountId> for Pallet<T, I> {
 	type Error = ListError;
 	type Score = T::Score;
 
@@ -321,45 +323,21 @@ impl<T: Config<I>, I: 'static> SortedListProvider<T::AccountId> for Pallet<T, I>
 	fn contains(id: &T::AccountId) -> bool {
 		List::<T, I>::contains(id)
 	}
-
-	fn on_insert(id: T::AccountId, score: T::Score) -> Result<(), ListError> {
-		List::<T, I>::insert(id, score)
-	}
-
 	fn get_score(id: &T::AccountId) -> Result<T::Score, ListError> {
 		List::<T, I>::get_score(id)
 	}
-
-	fn on_update(id: &T::AccountId, new_score: T::Score) -> Result<(), ListError> {
-		Pallet::<T, I>::do_rebag(id, new_score).map(|_| ())
-	}
-
-	fn on_remove(id: &T::AccountId) -> Result<(), ListError> {
-		List::<T, I>::remove(id)
-	}
-
-	fn unsafe_regenerate(
-		all: impl IntoIterator<Item = T::AccountId>,
-		score_of: Box<dyn Fn(&T::AccountId) -> T::Score>,
-	) -> u32 {
-		// NOTE: This call is unsafe for the same reason as SortedListProvider::unsafe_regenerate.
-		// I.e. because it can lead to many storage accesses.
-		// So it is ok to call it as caller must ensure the conditions.
-		List::<T, I>::unsafe_regenerate(all, score_of)
-	}
-
 	fn try_state() -> Result<(), &'static str> {
 		List::<T, I>::try_state()
 	}
 
-	fn unsafe_clear() {
-		// NOTE: This call is unsafe for the same reason as SortedListProvider::unsafe_clear.
-		// I.e. because it can lead to many storage accesses.
-		// So it is ok to call it as caller must ensure the conditions.
-		List::<T, I>::unsafe_clear()
-	}
+	frame_election_provider_support::runtime_benchmarks_or_test_enabled! {
+		fn unsafe_clear() {
+			// NOTE: This call is unsafe for the same reason as SortedListProvider::unsafe_clear.
+			// I.e. because it can lead to many storage accesses.
+			// So it is ok to call it as caller must ensure the conditions.
+			List::<T, I>::unsafe_clear()
+		}
 
-	frame_election_provider_support::runtime_benchmarks_enabled! {
 		fn score_update_worst_case(who: &T::AccountId, is_increase: bool) -> Self::Score {
 			use frame_support::traits::Get as _;
 			let thresholds = T::BagThresholds::get();
@@ -383,8 +361,32 @@ impl<T: Config<I>, I: 'static> SortedListProvider<T::AccountId> for Pallet<T, I>
 	}
 }
 
+impl<T: Config<I>, I: 'static> SortedListProvider<T::AccountId> for Pallet<T, I> {
+	fn on_insert(id: T::AccountId, score: T::Score) -> Result<(), ListError> {
+		List::<T, I>::insert(id, score)
+	}
+
+	fn on_update(id: &T::AccountId, new_score: T::Score) -> Result<(), ListError> {
+		Pallet::<T, I>::do_rebag(id, new_score).map(|_| ())
+	}
+
+	fn on_remove(id: &T::AccountId) -> Result<(), ListError> {
+		List::<T, I>::remove(id)
+	}
+
+	fn unsafe_regenerate(
+		all: impl IntoIterator<Item = T::AccountId>,
+		score_of: Box<dyn Fn(&T::AccountId) -> T::Score>,
+	) -> u32 {
+		// NOTE: This call is unsafe for the same reason as SortedListProvider::unsafe_regenerate.
+		// I.e. because it can lead to many storage accesses.
+		// So it is ok to call it as caller must ensure the conditions.
+		List::<T, I>::unsafe_regenerate(all, score_of)
+	}
+}
+
 impl<T: Config<I>, I: 'static> ScoreProvider<T::AccountId> for Pallet<T, I> {
-	type Score = <Pallet<T, I> as SortedListProvider<T::AccountId>>::Score;
+	type Score = <Pallet<T, I> as ReadOnlySortedListProvider<T::AccountId>>::Score;
 
 	fn score(id: &T::AccountId) -> T::Score {
 		Node::<T, I>::get(id).map(|node| node.score()).unwrap_or_default()

frame/bags-list/src/list/tests.rs

@@ -20,7 +20,7 @@ use crate::{
 	mock::{test_utils::*, *},
 	ListBags, ListNodes,
 };
-use frame_election_provider_support::{SortedListProvider, VoteWeight};
+use frame_election_provider_support::{ReadOnlySortedListProvider, VoteWeight};
 use frame_support::{assert_ok, assert_storage_noop};
 
 fn node(