[Feature] P2 Staking Tracker

Cargo.toml

@@ -141,6 +141,8 @@ members = [
 	"frame/staking",
 	"frame/staking/reward-curve",
 	"frame/staking/reward-fn",
+	"frame/stake-tracker",
+	"frame/stake-tracker/initializer",
 	"frame/state-trie-migration",
 	"frame/sudo",
 	"frame/root-offences",

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",

bin/node/runtime/src/lib.rs

@@ -553,6 +553,13 @@ impl pallet_staking::BenchmarkingConfig for StakingBenchmarkingConfig {
 	type MaxValidators = ConstU32<1000>;
 }
 
+impl pallet_stake_tracker::Config for Runtime {
+	type Currency = Balances;
+	type Staking = Staking;
+	type VoterList = VoterListTracker;
+	type TargetList = TargetList;
+}
+
 impl pallet_staking::Config for Runtime {
 	type MaxNominations = MaxNominations;
 	type Currency = Balances;
@@ -586,6 +593,7 @@ impl pallet_staking::Config for Runtime {
 	type OnStakerSlash = NominationPools;
 	type WeightInfo = pallet_staking::weights::SubstrateWeight<Runtime>;
 	type BenchmarkingConfig = StakingBenchmarkingConfig;
+	type EventListener = StakeTracker;
 }
 
 impl pallet_fast_unstake::Config for Runtime {
@@ -750,7 +758,7 @@ impl pallet_election_provider_multi_phase::Config for Runtime {
 }
 
 parameter_types! {
-	pub const BagThresholds: &'static [u64] = &voter_bags::THRESHOLDS;
+	pub const BagThresholds: &'static [VoteWeight] = &voter_bags::THRESHOLDS;
 }
 
 type VoterBagsListInstance = pallet_bags_list::Instance1;
@@ -764,6 +772,33 @@ impl pallet_bags_list::Config<VoterBagsListInstance> for Runtime {
 	type WeightInfo = pallet_bags_list::weights::SubstrateWeight<Runtime>;
 }
 
+// A special VoterList instance used to test the StakeTracker.
+type VoterBagsListTrackerInstance = pallet_bags_list::Instance3;
+impl pallet_bags_list::Config<VoterBagsListTrackerInstance> for Runtime {
+	type RuntimeEvent = RuntimeEvent;
+	// The voter bags-list is loosely kept up to date, and the real source of truth for the score
+	// of each node is the staking pallet.
+	type ScoreProvider = Staking;
+	type BagThresholds = BagThresholds;
+	type Score = VoteWeight;
+	type WeightInfo = pallet_bags_list::weights::SubstrateWeight<Runtime>;
+}
+
+parameter_types! {
+	pub const BagThresholdsBalances: &'static [Balance] = &voter_bags::THRESHOLDS_BALANCES;
+}
+
+// A TargetList, currently populated by StakeTracker, once this has been tested enough - this will
+// be used by pallet-staking as a list of electable targets.
+type TargetBagsListInstance = pallet_bags_list::Instance2;
+impl pallet_bags_list::Config<TargetBagsListInstance> for Runtime {
+	type RuntimeEvent = RuntimeEvent;
+	type ScoreProvider = StakeTracker;
+	type BagThresholds = BagThresholdsBalances;
+	type Score = Balance;
+	type WeightInfo = pallet_bags_list::weights::SubstrateWeight<Runtime>;
+}
+
 parameter_types! {
 	pub const PostUnbondPoolsWindow: u32 = 4;
 	pub const NominationPoolsPalletId: PalletId = PalletId(*b"py/nopls");
@@ -1743,6 +1778,9 @@ construct_runtime!(
 		Nfts: pallet_nfts,
 		TransactionStorage: pallet_transaction_storage,
 		VoterList: pallet_bags_list::<Instance1>,
+		TargetList: pallet_bags_list::<Instance2>,
+		// A special VoterList tha is used just to see if the stake-tracker works correctly.
+		VoterListTracker: pallet_bags_list::<Instance3>,
 		StateTrieMigration: pallet_state_trie_migration,
 		ChildBounties: pallet_child_bounties,
 		Referenda: pallet_referenda,
@@ -1756,6 +1794,7 @@ construct_runtime!(
 		RankedPolls: pallet_referenda::<Instance2>,
 		RankedCollective: pallet_ranked_collective,
 		FastUnstake: pallet_fast_unstake,
+		StakeTracker: pallet_stake_tracker,
 		MessageQueue: pallet_message_queue,
 	}
 );