move session handler traits to frame-support

frame/authority-discovery/src/lib.rs

@@ -53,7 +53,7 @@ pub mod pallet {
 		Vec<AuthorityId>,
 		ValueQuery,
 	>;
-	
+
 	#[pallet::storage]
 	#[pallet::getter(fn next_keys)]
 	/// Keys of the next authority set.
@@ -172,11 +172,11 @@ mod tests {
 	use super::*;
 	use sp_authority_discovery::AuthorityPair;
 	use sp_application_crypto::Pair;
-	use sp_core::{crypto::key_types, H256};
+	use sp_core::H256;
 	use sp_io::TestExternalities;
 	use sp_runtime::{
-		testing::{Header, UintAuthorityId}, traits::{ConvertInto, IdentityLookup, OpaqueKeys},
-		Perbill, KeyTypeId,
+		testing::{Header, UintAuthorityId}, traits::{ConvertInto, IdentityLookup},
+		Perbill,
 	};
 	use frame_support::parameter_types;
 
@@ -205,7 +205,7 @@ mod tests {
 		type SessionManager = ();
 		type Keys = UintAuthorityId;
 		type ShouldEndSession = pallet_session::PeriodicSessions<Period, Offset>;
-		type SessionHandler = TestSessionHandler;
+		type SessionHandler = frame_support::traits::TestSessionHandler;
 		type Event = Event;
 		type ValidatorId = AuthorityId;
 		type ValidatorIdOf = ConvertInto;
@@ -256,22 +256,6 @@ mod tests {
 		type OnSetCode = ();
 	}
 
-	pub struct TestSessionHandler;
-	impl pallet_session::SessionHandler<AuthorityId> for TestSessionHandler {
-		const KEY_TYPE_IDS: &'static [KeyTypeId] = &[key_types::DUMMY];
-
-		fn on_new_session<Ks: OpaqueKeys>(
-			_changed: bool,
-			_validators: &[(AuthorityId, Ks)],
-			_queued_validators: &[(AuthorityId, Ks)],
-		) {
-		}
-
-		fn on_disabled(_validator_index: usize) {}
-
-		fn on_genesis_session<Ks: OpaqueKeys>(_validators: &[(AuthorityId, Ks)]) {}
-	}
-
 	#[test]
 	fn authorities_returns_current_and_next_authority_set() {
 		// The whole authority discovery pallet ignores account ids, but we still need them for

frame/offences/benchmarking/src/mock.rs

@@ -100,21 +100,6 @@ sp_runtime::impl_opaque_keys! {
 	}
 }
 
-pub struct TestSessionHandler;
-impl pallet_session::SessionHandler<AccountId> for TestSessionHandler {
-	const KEY_TYPE_IDS: &'static [sp_runtime::KeyTypeId] = &[];
-
-	fn on_genesis_session<Ks: sp_runtime::traits::OpaqueKeys>(_validators: &[(AccountId, Ks)]) {}
-
-	fn on_new_session<Ks: sp_runtime::traits::OpaqueKeys>(
-		_: bool,
-		_: &[(AccountId, Ks)],
-		_: &[(AccountId, Ks)],
-	) {}
-
-	fn on_disabled(_: usize) {}
-}
-
 parameter_types! {
 	pub const Period: u64 = 1;
 	pub const Offset: u64 = 0;
@@ -125,7 +110,7 @@ impl pallet_session::Config for Test {
 	type Keys = SessionKeys;
 	type ShouldEndSession = pallet_session::PeriodicSessions<Period, Offset>;
 	type NextSessionRotation = pallet_session::PeriodicSessions<Period, Offset>;
-	type SessionHandler = TestSessionHandler;
+	type SessionHandler = frame_support::traits::TestSessionHandler;
 	type Event = Event;
 	type ValidatorId = AccountId;
 	type ValidatorIdOf = pallet_staking::StashOf<Test>;

frame/session/benchmarking/src/mock.rs

@@ -102,27 +102,12 @@ sp_runtime::impl_opaque_keys! {
 	}
 }
 
-pub struct TestSessionHandler;
-impl pallet_session::SessionHandler<AccountId> for TestSessionHandler {
-	const KEY_TYPE_IDS: &'static [sp_runtime::KeyTypeId] = &[];
-
-	fn on_genesis_session<Ks: sp_runtime::traits::OpaqueKeys>(_validators: &[(AccountId, Ks)]) {}
-
-	fn on_new_session<Ks: sp_runtime::traits::OpaqueKeys>(
-		_: bool,
-		_: &[(AccountId, Ks)],
-		_: &[(AccountId, Ks)],
-	) {}
-
-	fn on_disabled(_: usize) {}
-}
-
 impl pallet_session::Config for Test {
 	type SessionManager = pallet_session::historical::NoteHistoricalRoot<Test, Staking>;
 	type Keys = SessionKeys;
 	type ShouldEndSession = pallet_session::PeriodicSessions<(), ()>;
 	type NextSessionRotation = pallet_session::PeriodicSessions<(), ()>;
-	type SessionHandler = TestSessionHandler;
+	type SessionHandler = frame_support::traits::TestSessionHandler;
 	type Event = Event;
 	type ValidatorId = AccountId;
 	type ValidatorIdOf = pallet_staking::StashOf<Test>;

frame/session/src/lib.rs

@@ -118,14 +118,14 @@ use sp_std::{prelude::*, marker::PhantomData, ops::{Sub, Rem}};
 use codec::Decode;
 use sp_runtime::{
 	traits::{AtLeast32BitUnsigned, Convert, Member, One, OpaqueKeys, Zero},
-	KeyTypeId, Perbill, Percent, RuntimeAppPublic,
+	KeyTypeId, Perbill, Percent,
 };
 use sp_staking::SessionIndex;
 use frame_support::{
 	ensure, decl_module, decl_event, decl_storage, decl_error, ConsensusEngineId, Parameter,
 	traits::{
 		Get, FindAuthor, ValidatorRegistration, EstimateNextSessionRotation, EstimateNextNewSession,
-		OneSessionHandler, ValidatorSet,
+		ValidatorSet, SessionHandler
 	},
 	dispatch::{self, DispatchResult, DispatchError},
 	weights::Weight,
@@ -255,101 +255,6 @@ impl<A> SessionManager<A> for () {
 	fn end_session(_: SessionIndex) {}
 }
 
-/// Handler for session life cycle events.
-pub trait SessionHandler<ValidatorId> {
-	/// All the key type ids this session handler can process.
-	///
-	/// The order must be the same as it expects them in
-	/// [`on_new_session`](Self::on_new_session<Ks>) and [`on_genesis_session`](Self::on_genesis_session<Ks>).
-	const KEY_TYPE_IDS: &'static [KeyTypeId];
-
-	/// The given validator set will be used for the genesis session.
-	/// It is guaranteed that the given validator set will also be used
-	/// for the second session, therefore the first call to `on_new_session`
-	/// should provide the same validator set.
-	fn on_genesis_session<Ks: OpaqueKeys>(validators: &[(ValidatorId, Ks)]);
-
-	/// Session set has changed; act appropriately. Note that this can be called
-	/// before initialization of your module.
-	///
-	/// `changed` is true whenever any of the session keys or underlying economic
-	/// identities or weightings behind those keys has changed.
-	fn on_new_session<Ks: OpaqueKeys>(
-		changed: bool,
-		validators: &[(ValidatorId, Ks)],
-		queued_validators: &[(ValidatorId, Ks)],
-	);
-
-	/// A notification for end of the session.
-	///
-	/// Note it is triggered before any [`SessionManager::end_session`] handlers,
-	/// so we can still affect the validator set.
-	fn on_before_session_ending() {}
-
-	/// A validator got disabled. Act accordingly until a new session begins.
-	fn on_disabled(validator_index: usize);
-}
-
-#[impl_trait_for_tuples::impl_for_tuples(1, 30)]
-#[tuple_types_custom_trait_bound(OneSessionHandler<AId>)]
-impl<AId> SessionHandler<AId> for Tuple {
-	for_tuples!(
-		const KEY_TYPE_IDS: &'static [KeyTypeId] = &[ #( <Tuple::Key as RuntimeAppPublic>::ID ),* ];
-	);
-
-	fn on_genesis_session<Ks: OpaqueKeys>(validators: &[(AId, Ks)]) {
-		for_tuples!(
-			#(
-				let our_keys: Box<dyn Iterator<Item=_>> = Box::new(validators.iter()
-					.map(|k| (&k.0, k.1.get::<Tuple::Key>(<Tuple::Key as RuntimeAppPublic>::ID)
-						.unwrap_or_default())));
-
-				Tuple::on_genesis_session(our_keys);
-			)*
-		)
-	}
-
-	fn on_new_session<Ks: OpaqueKeys>(
-		changed: bool,
-		validators: &[(AId, Ks)],
-		queued_validators: &[(AId, Ks)],
-	) {
-		for_tuples!(
-			#(
-				let our_keys: Box<dyn Iterator<Item=_>> = Box::new(validators.iter()
-					.map(|k| (&k.0, k.1.get::<Tuple::Key>(<Tuple::Key as RuntimeAppPublic>::ID)
-						.unwrap_or_default())));
-				let queued_keys: Box<dyn Iterator<Item=_>> = Box::new(queued_validators.iter()
-					.map(|k| (&k.0, k.1.get::<Tuple::Key>(<Tuple::Key as RuntimeAppPublic>::ID)
-						.unwrap_or_default())));
-				Tuple::on_new_session(changed, our_keys, queued_keys);
-			)*
-		)
-	}
-
-	fn on_before_session_ending() {
-		for_tuples!( #( Tuple::on_before_session_ending(); )* )
-	}
-
-	fn on_disabled(i: usize) {
-		for_tuples!( #( Tuple::on_disabled(i); )* )
-	}
-}
-
-/// `SessionHandler` for tests that use `UintAuthorityId` as `Keys`.
-pub struct TestSessionHandler;
-impl<AId> SessionHandler<AId> for TestSessionHandler {
-	const KEY_TYPE_IDS: &'static [KeyTypeId] = &[sp_runtime::key_types::DUMMY];
-
-	fn on_genesis_session<Ks: OpaqueKeys>(_: &[(AId, Ks)]) {}
-
-	fn on_new_session<Ks: OpaqueKeys>(_: bool, _: &[(AId, Ks)], _: &[(AId, Ks)]) {}
-
-	fn on_before_session_ending() {}
-
-	fn on_disabled(_: usize) {}
-}
-
 impl<T: Config> ValidatorRegistration<T::ValidatorId> for Module<T> {
 	fn is_registered(id: &T::ValidatorId) -> bool {
 		Self::load_keys(id).is_some()

frame/session/src/mock.rs

@@ -22,7 +22,7 @@ use std::cell::RefCell;
 use frame_support::{parameter_types, BasicExternalities};
 use sp_core::{crypto::key_types::DUMMY, H256};
 use sp_runtime::{
-	Perbill, impl_opaque_keys,
+	Perbill, impl_opaque_keys, RuntimeAppPublic,
 	traits::{BlakeTwo256, IdentityLookup, ConvertInto},
 	testing::{Header, UintAuthorityId},
 };
@@ -119,7 +119,7 @@ impl ShouldEndSession<u64> for TestShouldEndSession {
 }
 
 pub struct TestSessionHandler;
-impl SessionHandler<u64> for TestSessionHandler {
+impl frame_support::traits::SessionHandler<u64> for TestSessionHandler {
 	const KEY_TYPE_IDS: &'static [sp_runtime::KeyTypeId] = &[UintAuthorityId::ID];
 	fn on_genesis_session<T: OpaqueKeys>(_validators: &[(u64, T)]) {}
 	fn on_new_session<T: OpaqueKeys>(

frame/staking/fuzzer/src/mock.rs

@@ -105,27 +105,12 @@ sp_runtime::impl_opaque_keys! {
 	}
 }
 
-pub struct TestSessionHandler;
-impl pallet_session::SessionHandler<AccountId> for TestSessionHandler {
-	const KEY_TYPE_IDS: &'static [sp_runtime::KeyTypeId] = &[];
-
-	fn on_genesis_session<Ks: sp_runtime::traits::OpaqueKeys>(_validators: &[(AccountId, Ks)]) {}
-
-	fn on_new_session<Ks: sp_runtime::traits::OpaqueKeys>(
-		_: bool,
-		_: &[(AccountId, Ks)],
-		_: &[(AccountId, Ks)],
-	) {}
-
-	fn on_disabled(_: usize) {}
-}
-
 impl pallet_session::Config for Test {
 	type SessionManager = pallet_session::historical::NoteHistoricalRoot<Test, Staking>;
 	type Keys = SessionKeys;
 	type ShouldEndSession = pallet_session::PeriodicSessions<(), ()>;
 	type NextSessionRotation = pallet_session::PeriodicSessions<(), ()>;
-	type SessionHandler = TestSessionHandler;
+	type SessionHandler = frame_support::traits::TestSessionHandler;
 	type Event = Event;
 	type ValidatorId = AccountId;
 	type ValidatorIdOf = pallet_staking::StashOf<Test>;

frame/staking/src/lib.rs

@@ -648,7 +648,7 @@ impl<T: Config> SessionInterface<<T as frame_system::Config>::AccountId> for T w
 		FullIdentification = Exposure<<T as frame_system::Config>::AccountId, BalanceOf<T>>,
 		FullIdentificationOf = ExposureOf<T>,
 	>,
-	T::SessionHandler: pallet_session::SessionHandler<<T as frame_system::Config>::AccountId>,
+	T::SessionHandler: frame_support::traits::SessionHandler<<T as frame_system::Config>::AccountId>,
 	T::SessionManager: pallet_session::SessionManager<<T as frame_system::Config>::AccountId>,
 	T::ValidatorIdOf:
 		Convert<<T as frame_system::Config>::AccountId, Option<<T as frame_system::Config>::AccountId>>,
@@ -2754,7 +2754,7 @@ where
 		FullIdentification = Exposure<<T as frame_system::Config>::AccountId, BalanceOf<T>>,
 		FullIdentificationOf = ExposureOf<T>,
 	>,
-	T::SessionHandler: pallet_session::SessionHandler<<T as frame_system::Config>::AccountId>,
+	T::SessionHandler: frame_support::traits::SessionHandler<<T as frame_system::Config>::AccountId>,
 	T::SessionManager: pallet_session::SessionManager<<T as frame_system::Config>::AccountId>,
 	T::ValidatorIdOf: Convert<
 		<T as frame_system::Config>::AccountId,

frame/support/src/traits.rs

@@ -38,7 +38,7 @@ mod validation;
 pub use validation::{
 	ValidatorSet, ValidatorSetWithIdentification, OneSessionHandler, FindAuthor, VerifySeal,
 	EstimateNextNewSession, EstimateNextSessionRotation, KeyOwnerProofSystem, ValidatorRegistration,
-	Lateness,
+	Lateness, SessionHandler, TestSessionHandler
 };
 
 mod filter;