chore: add events for deposit owner changes (#738)

Fixes KILTprotocol/ticket#3074.

Cc @kilted-andres 

I tried to keep the event structure in all pallets the same, with the
same name and the same fields `id`, `from` and `to`. The `id` field has
a different type depending on the pallet, but the `from` and `to` are
all the same.

pallets/attestation/src/lib.rs

@@ -236,6 +236,15 @@ pub mod pallet {
 			/// was deleted.
 			claim_hash: ClaimHashOf<T>,
 		},
+		/// The deposit for an attestation has changed owner.
+		DepositOwnerChanged {
+			/// The claim hash of the credential whose deposit owner changed.
+			id: ClaimHashOf<T>,
+			/// The old deposit owner.
+			from: AccountIdOf<T>,
+			/// The new deposit owner.
+			to: AccountIdOf<T>,
+		},
 	}
 
 	#[pallet::error]
@@ -475,10 +484,15 @@ pub mod pallet {
 			let attestation = Attestations::<T>::get(claim_hash).ok_or(Error::<T>::NotFound)?;
 			ensure!(attestation.attester == subject, Error::<T>::NotAuthorized);
 
-			AttestationStorageDepositCollector::<T>::change_deposit_owner::<BalanceMigrationManagerOf<T>>(
-				&claim_hash,
-				sender,
-			)?;
+			let old_deposit_owner = AttestationStorageDepositCollector::<T>::change_deposit_owner::<
+				BalanceMigrationManagerOf<T>,
+			>(&claim_hash, sender.clone())?;
+
+			Self::deposit_event(Event::<T>::DepositOwnerChanged {
+				id: claim_hash,
+				from: old_deposit_owner,
+				to: sender,
+			});
 
 			Ok(())
 		}

pallets/attestation/src/tests/deposit.rs

@@ -77,6 +77,13 @@ fn test_change_deposit_owner() {
 				Balances::balance_on_hold(&HoldReason::Deposit.into(), &ACCOUNT_01),
 				<Test as Config>::Deposit::get()
 			);
+			assert!(System::events().iter().any(|e| e.event
+				== Event::<Test>::DepositOwnerChanged {
+					id: claim_hash,
+					from: ACCOUNT_00,
+					to: ACCOUNT_01
+				}
+				.into()));
 		});
 }
 

pallets/delegation/src/lib.rs

@@ -248,6 +248,15 @@ pub mod pallet {
 		/// A delegation has been removed.
 		/// \[remover ID, delegation node ID\]
 		DelegationRemoved(AccountIdOf<T>, DelegationNodeIdOf<T>),
+		/// The deposit for a delegation has changed owner.
+		DepositOwnerChanged {
+			/// The ID of the delegation whose deposit owner changed.
+			id: DelegationNodeIdOf<T>,
+			/// The old deposit owner.
+			from: AccountIdOf<T>,
+			/// The new deposit owner.
+			to: AccountIdOf<T>,
+		},
 	}
 
 	#[pallet::error]
@@ -683,17 +692,25 @@ pub mod pallet {
 		#[pallet::weight(<T as Config>::WeightInfo::change_deposit_owner())]
 		pub fn change_deposit_owner(origin: OriginFor<T>, delegation_id: DelegationNodeIdOf<T>) -> DispatchResult {
 			let source = <T as Config>::EnsureOrigin::ensure_origin(origin)?;
+			let sender = source.sender();
 
 			let delegation = DelegationNodes::<T>::get(delegation_id).ok_or(Error::<T>::DelegationNotFound)?;
 
 			// Deposit can only be swapped by the owner of the delegation node, not the
 			// parent or another ancestor.
 			ensure!(delegation.details.owner == source.subject(), Error::<T>::AccessDenied);
 
-			DelegationDepositCollector::<T>::change_deposit_owner::<BalanceMigrationManagerOf<T>>(
-				&delegation_id,
-				source.sender(),
-			)
+			let old_deposit_owner = DelegationDepositCollector::<T>::change_deposit_owner::<
+				BalanceMigrationManagerOf<T>,
+			>(&delegation_id, sender.clone())?;
+
+			Self::deposit_event(Event::<T>::DepositOwnerChanged {
+				id: delegation_id,
+				from: old_deposit_owner,
+				to: sender,
+			});
+
+			Ok(())
 		}
 
 		/// Updates the deposit amount to the current deposit rate.

pallets/delegation/src/mock.rs

@@ -232,7 +232,7 @@ pub(crate) mod runtime {
 		type AccountId = AccountId;
 		type Lookup = IdentityLookup<Self::AccountId>;
 
-		type RuntimeEvent = ();
+		type RuntimeEvent = RuntimeEvent;
 		type BlockHashCount = BlockHashCount;
 		type DbWeight = RocksDbWeight;
 		type Version = ();
@@ -264,7 +264,7 @@ pub(crate) mod runtime {
 		type MaxFreezes = MaxFreezes;
 		type Balance = Balance;
 		type DustRemoval = ();
-		type RuntimeEvent = ();
+		type RuntimeEvent = RuntimeEvent;
 		type ExistentialDeposit = ExistentialDeposit;
 		type AccountStore = System;
 		type WeightInfo = ();
@@ -288,7 +288,7 @@ pub(crate) mod runtime {
 		type EnsureOrigin = mock_origin::EnsureDoubleOrigin<AccountId, Self::CtypeCreatorId>;
 		type OriginSuccess = mock_origin::DoubleOrigin<AccountId, Self::CtypeCreatorId>;
 		type OverarchingOrigin = EnsureSigned<AccountId>;
-		type RuntimeEvent = ();
+		type RuntimeEvent = RuntimeEvent;
 		type WeightInfo = ();
 
 		type Currency = Balances;
@@ -305,7 +305,7 @@ pub(crate) mod runtime {
 		type EnsureOrigin = mock_origin::EnsureDoubleOrigin<AccountId, DelegatorIdOf<Self>>;
 		type OriginSuccess = mock_origin::DoubleOrigin<AccountId, DelegatorIdOf<Self>>;
 		type RuntimeHoldReason = RuntimeHoldReason;
-		type RuntimeEvent = ();
+		type RuntimeEvent = RuntimeEvent;
 		type WeightInfo = ();
 
 		type Currency = Balances;
@@ -335,7 +335,7 @@ pub(crate) mod runtime {
 		type DelegationNodeId = Hash;
 		type EnsureOrigin = mock_origin::EnsureDoubleOrigin<AccountId, Self::DelegationEntityId>;
 		type OriginSuccess = mock_origin::DoubleOrigin<AccountId, Self::DelegationEntityId>;
-		type RuntimeEvent = ();
+		type RuntimeEvent = RuntimeEvent;
 		type MaxSignatureByteLength = MaxSignatureByteLength;
 		type MaxParentChecks = MaxParentChecks;
 		type MaxRevocations = MaxRevocations;
@@ -503,6 +503,10 @@ pub(crate) mod runtime {
 			let mut ext = sp_io::TestExternalities::new(storage);
 
 			ext.execute_with(|| {
+				// ensure that we are not at the genesis block. Events are not registered for
+				// the genesis block.
+				System::set_block_number(System::block_number() + 1);
+
 				for (ctype_hash, owner) in self.ctypes.iter() {
 					ctype::Ctypes::<Test>::insert(
 						ctype_hash,

pallets/delegation/src/tests/deposit.rs

@@ -23,7 +23,7 @@ use frame_support::{
 use kilt_support::mock::mock_origin::DoubleOrigin;
 use sp_runtime::{traits::Zero, TokenError};
 
-use crate::{self as delegation, mock::*, Config, Error, HoldReason};
+use crate::{self as delegation, mock::*, Config, Error, Event, HoldReason};
 
 #[test]
 fn test_change_deposit_owner() {
@@ -75,6 +75,13 @@ fn test_change_deposit_owner() {
 				Balances::balance_on_hold(&HoldReason::Deposit.into(), &ACCOUNT_01),
 				<Test as Config>::Deposit::get()
 			);
+			assert!(System::events().iter().any(|e| e.event
+				== Event::<Test>::DepositOwnerChanged {
+					id: delegation_id,
+					from: ACCOUNT_00,
+					to: ACCOUNT_01
+				}
+				.into()));
 		});
 }
 

pallets/did/src/lib.rs

@@ -369,6 +369,15 @@ pub mod pallet {
 		/// A DID-authorised call has been executed.
 		/// \[DID caller, dispatch result\]
 		DidCallDispatched(DidIdentifierOf<T>, DispatchResult),
+		/// The deposit for a DID has changed owner.
+		DepositOwnerChanged {
+			/// The DID whose deposit owner changed.
+			id: DidIdentifierOf<T>,
+			/// The old deposit owner.
+			from: AccountIdOf<T>,
+			/// The new deposit owner.
+			to: AccountIdOf<T>,
+		},
 	}
 
 	#[pallet::error]
@@ -1105,7 +1114,15 @@ pub mod pallet {
 			let subject = source.subject();
 			let sender = source.sender();
 
-			DidDepositCollector::<T>::change_deposit_owner::<<T as Config>::BalanceMigrationManager>(&subject, sender)?;
+			let old_deposit_owner = DidDepositCollector::<T>::change_deposit_owner::<
+				<T as Config>::BalanceMigrationManager,
+			>(&subject, sender.clone())?;
+
+			Self::deposit_event(Event::<T>::DepositOwnerChanged {
+				id: subject,
+				from: old_deposit_owner,
+				to: sender,
+			});
 
 			Ok(())
 		}

pallets/did/src/tests/deposit.rs

@@ -167,6 +167,13 @@ fn test_change_deposit_owner() {
 				Balances::balance_on_hold(&HoldReason::Deposit.into(), &alice_did),
 				<Test as did::Config>::BaseDeposit::get()
 			);
+			assert!(System::events().iter().any(|e| e.event
+				== Event::<Test>::DepositOwnerChanged {
+					id: alice_did,
+					from: ACCOUNT_00,
+					to: ACCOUNT_01
+				}
+				.into()));
 		});
 }
 

pallets/pallet-did-lookup/src/lib.rs

@@ -153,6 +153,15 @@ pub mod pallet {
 
 		/// All AccountIds have been migrated to LinkableAccountId.
 		MigrationCompleted,
+		/// The deposit for an linked account has changed owner.
+		DepositOwnerChanged {
+			/// The tuple of (DID, linked account) whose deposit owner changed.
+			id: (DidIdentifierOf<T>, LinkableAccountId),
+			/// The old deposit owner.
+			from: AccountIdOf<T>,
+			/// The new deposit owner.
+			to: AccountIdOf<T>,
+		},
 	}
 
 	#[pallet::error]
@@ -374,14 +383,22 @@ pub mod pallet {
 		pub fn change_deposit_owner(origin: OriginFor<T>, account: LinkableAccountId) -> DispatchResult {
 			let source = <T as Config>::EnsureOrigin::ensure_origin(origin)?;
 			let subject = source.subject();
+			let sender = source.sender();
 
 			let record = ConnectedDids::<T>::get(&account).ok_or(Error::<T>::NotFound)?;
 			ensure!(record.did == subject, Error::<T>::NotAuthorized);
 
-			LinkableAccountDepositCollector::<T>::change_deposit_owner::<BalanceMigrationManagerOf<T>>(
-				&account,
-				source.sender(),
-			)
+			let old_deposit_owner = LinkableAccountDepositCollector::<T>::change_deposit_owner::<
+				BalanceMigrationManagerOf<T>,
+			>(&account, sender.clone())?;
+
+			Self::deposit_event(Event::<T>::DepositOwnerChanged {
+				id: (subject, account),
+				from: old_deposit_owner,
+				to: sender,
+			});
+
+			Ok(())
 		}
 
 		/// Updates the deposit amount to the current deposit rate.

pallets/pallet-did-lookup/src/mock.rs

@@ -189,6 +189,10 @@ impl ExtBuilder {
 		let mut ext = sp_io::TestExternalities::new(storage);
 
 		ext.execute_with(|| {
+			// ensure that we are not at the genesis block. Events are not registered for
+			// the genesis block.
+			System::set_block_number(System::block_number() + 1);
+
 			for (sender, did, account) in self.connections {
 				pallet_did_lookup::Pallet::<Test>::add_association(sender, did, account)
 					.expect("Should create connection");

pallets/pallet-did-lookup/src/tests/deposit.rs

@@ -19,7 +19,7 @@ use frame_support::{assert_noop, assert_ok, traits::fungible::InspectHold};
 use kilt_support::mock::mock_origin;
 use sp_runtime::{traits::Zero, TokenError};
 
-use crate::{mock::*, Error, HoldReason};
+use crate::{mock::*, Error, Event, HoldReason};
 
 #[test]
 fn test_change_deposit_owner() {
@@ -39,6 +39,13 @@ fn test_change_deposit_owner() {
 				Balances::balance_on_hold(&HoldReason::Deposit.into(), &ACCOUNT_01),
 				<Test as crate::Config>::Deposit::get()
 			);
+			assert!(System::events().iter().any(|e| e.event
+				== Event::<Test>::DepositOwnerChanged {
+					id: (DID_00, LINKABLE_ACCOUNT_00),
+					from: ACCOUNT_00,
+					to: ACCOUNT_01
+				}
+				.into()));
 		})
 }
 

pallets/pallet-web3-names/src/lib.rs

@@ -162,6 +162,15 @@ pub mod pallet {
 		Web3NameBanned { name: Web3NameOf<T> },
 		/// A name has been unbanned.
 		Web3NameUnbanned { name: Web3NameOf<T> },
+		/// The deposit for a web3name has changed owner.
+		DepositOwnerChanged {
+			/// The web3name whose deposit owner changed.
+			id: Web3NameOf<T>,
+			/// The old deposit owner.
+			from: AccountIdOf<T>,
+			/// The new deposit owner.
+			to: AccountIdOf<T>,
+		},
 	}
 
 	#[pallet::error]
@@ -353,11 +362,18 @@ pub mod pallet {
 		pub fn change_deposit_owner(origin: OriginFor<T>) -> DispatchResult {
 			let source = <T as Config>::OwnerOrigin::ensure_origin(origin)?;
 			let w3n_owner = source.subject();
+			let sender = source.sender();
 			let name = Names::<T>::get(&w3n_owner).ok_or(Error::<T>::NotFound)?;
-			Web3NameStorageDepositCollector::<T>::change_deposit_owner::<BalanceMigrationManagerOf<T>>(
-				&name,
-				source.sender(),
-			)?;
+
+			let old_deposit_owner = Web3NameStorageDepositCollector::<T>::change_deposit_owner::<
+				BalanceMigrationManagerOf<T>,
+			>(&name, sender.clone())?;
+
+			Self::deposit_event(Event::<T>::DepositOwnerChanged {
+				id: name,
+				from: old_deposit_owner,
+				to: sender,
+			});
 
 			Ok(())
 		}

pallets/pallet-web3-names/src/mock.rs

@@ -224,6 +224,10 @@ pub(crate) mod runtime {
 			let mut ext = sp_io::TestExternalities::new(storage);
 
 			ext.execute_with(|| {
+				// ensure that we are not at the genesis block. Events are not registered for
+				// the genesis block.
+				System::set_block_number(System::block_number() + 1);
+
 				for (owner, web3_name, payer) in self.claimed_web3_names {
 					pallet_web3_names::Pallet::<Test>::register_name(web3_name, owner, payer)
 						.expect("Could not register name");

pallets/pallet-web3-names/src/tests/claim.rs

@@ -52,7 +52,7 @@ fn claiming_successful() {
 				owner_details,
 				Web3OwnershipOf::<Test> {
 					owner: DID_00,
-					claimed_at: 0,
+					claimed_at: 1,
 					deposit: Deposit {
 						owner: ACCOUNT_00,
 						amount: Web3NameDeposit::get(),

pallets/pallet-web3-names/src/tests/deposit.rs

@@ -21,7 +21,7 @@ use frame_support::{assert_noop, assert_ok, traits::fungible::InspectHold};
 use kilt_support::{mock::mock_origin, Deposit};
 use sp_runtime::{traits::Zero, TokenError};
 
-use crate::{mock::*, Config, Error, HoldReason, Owner, Pallet};
+use crate::{mock::*, Config, Error, Event, HoldReason, Owner, Pallet};
 
 #[test]
 fn test_change_deposit_owner() {
@@ -48,6 +48,13 @@ fn test_change_deposit_owner() {
 				Balances::balance_on_hold(&HoldReason::Deposit.into(), &ACCOUNT_01),
 				<Test as Config>::Deposit::get()
 			);
+			assert!(System::events().iter().any(|e| e.event
+				== Event::<Test>::DepositOwnerChanged {
+					id: web3_name_00.clone(),
+					from: ACCOUNT_00,
+					to: ACCOUNT_01
+				}
+				.into()));
 		})
 }