[pallet-broker] add extrinsic to remove a lease

prdoc/pr_7026.prdoc

@@ -0,0 +1,17 @@
+# Schema: Polkadot SDK PRDoc Schema (prdoc) v1.0.0
+# See doc at https://raw.githubusercontent.com/paritytech/polkadot-sdk/master/prdoc/schema_user.json
+
+title: "[pallet-broker] add extrinsic to remove a lease"
+
+doc:
+  - audience: Runtime User
+    description: |
+      A new `remove_lease` extrinsic is introduced to the broker pallet to allow a lease to be removed by the root origin.
+
+crates:
+  - name: pallet-broker
+    bump: major
+  - name: coretime-rococo-runtime
+    bump: patch
+  - name: coretime-westend-runtime
+    bump: patch

substrate/frame/broker/src/benchmarking.rs

@@ -191,6 +191,25 @@ mod benches {
 		Ok(())
 	}
 
+	#[benchmark]
+	fn remove_lease() -> Result<(), BenchmarkError> {
+		let task = 1u32;
+		let until = 10u32.into();
+
+		// Assume Leases to be almost filled for worst case
+		setup_leases::<T>(T::MaxLeasedCores::get(), task, until);
+
+		let origin =
+			T::AdminOrigin::try_successful_origin().map_err(|_| BenchmarkError::Weightless)?;
+
+		#[extrinsic_call]
+		_(origin as T::RuntimeOrigin, task);
+
+		assert_eq!(Leases::<T>::get().len(), T::MaxLeasedCores::get().saturating_sub(1) as usize);
+
+		Ok(())
+	}
+
 	#[benchmark]
 	fn start_sales(n: Linear<0, { MAX_CORE_COUNT.into() }>) -> Result<(), BenchmarkError> {
 		let config = new_config_record::<T>();

substrate/frame/broker/src/dispatchable_impls.rs

@@ -91,6 +91,15 @@ impl<T: Config> Pallet<T> {
 		Ok(())
 	}
 
+	pub(crate) fn do_remove_lease(task: TaskId) -> DispatchResult {
+		let mut r = Leases::<T>::get();
+		let i = r.iter().position(|lease| lease.task == task).ok_or(Error::<T>::LeaseNotFound)?;
+		r.remove(i);
+		Leases::<T>::put(r);
+		Self::deposit_event(Event::<T>::LeaseRemoved { task });
+		Ok(())
+	}
+
 	pub(crate) fn do_start_sales(
 		end_price: BalanceOf<T>,
 		extra_cores: CoreIndex,

substrate/frame/broker/src/lib.rs

@@ -333,6 +333,11 @@ pub mod pallet {
 			/// longer apply).
 			until: Timeslice,
 		},
+		/// A lease has been removed.
+		LeaseRemoved {
+			/// The task to which a core was assigned.
+			task: TaskId,
+		},
 		/// A lease is about to end.
 		LeaseEnding {
 			/// The task to which a core was assigned.
@@ -512,6 +517,8 @@ pub mod pallet {
 		TooManyReservations,
 		/// The maximum amount of leases has already been reached.
 		TooManyLeases,
+		/// The lease does not exist.
+		LeaseNotFound,
 		/// The revenue for the Instantaneous Core Sales of this period is not (yet) known and thus
 		/// this operation cannot proceed.
 		UnknownRevenue,
@@ -969,6 +976,16 @@ pub mod pallet {
 			Ok(Pays::No.into())
 		}
 
+		/// Remove a lease.
+		///
+		/// - `origin`: Must be Root or pass `AdminOrigin`.
+		/// - `task`: The workload of the lease which should be removed.
+		#[pallet::call_index(24)]
+		pub fn remove_lease(origin: OriginFor<T>, task: TaskId) -> DispatchResult {
+			T::AdminOrigin::ensure_origin_or_root(origin)?;
+			Self::do_remove_lease(task)
+		}
+
 		#[pallet::call_index(99)]
 		#[pallet::weight(T::WeightInfo::swap_leases())]
 		pub fn swap_leases(origin: OriginFor<T>, id: TaskId, other: TaskId) -> DispatchResult {

substrate/frame/broker/src/tests.rs

@@ -1205,6 +1205,18 @@ fn leases_are_limited() {
 	});
 }
 
+#[test]
+fn remove_lease_works() {
+	TestExt::new().execute_with(|| {
+		Leases::<Test>::put(
+			BoundedVec::try_from(vec![LeaseRecordItem { task: 1u32, until: 10u32 }]).unwrap(),
+		);
+		assert_noop!(Broker::do_remove_lease(2), Error::<Test>::LeaseNotFound);
+		assert_ok!(Broker::do_remove_lease(1));
+		assert_noop!(Broker::do_remove_lease(1), Error::<Test>::LeaseNotFound);
+	});
+}
+
 #[test]
 fn purchase_requires_valid_status_and_sale_info() {
 	TestExt::new().execute_with(|| {