make trigger_call free and operational

authority/src/lib.rs

@@ -26,7 +26,7 @@ use frame_support::{
 		schedule::{DispatchTime, Named as ScheduleNamed, Priority},
 		EnsureOrigin, Get, IsType, OriginTrait,
 	},
-	weights::GetDispatchInfo,
+	weights::{DispatchClass, GetDispatchInfo, Pays},
 };
 use frame_system::{pallet_prelude::*, EnsureOneOf, EnsureRoot, EnsureSigned};
 use sp_runtime::{
@@ -377,12 +377,15 @@ pub mod module {
 			})
 		}
 
-		#[pallet::weight(T::WeightInfo::trigger_call().saturating_add(*call_weight_bound))]
+		#[pallet::weight((
+			T::WeightInfo::trigger_call().saturating_add(*call_weight_bound),
+			DispatchClass::Operational,
+		))]
 		pub fn trigger_call(
 			origin: OriginFor<T>,
 			hash: T::Hash,
 			#[pallet::compact] call_weight_bound: Weight,
-		) -> DispatchResult {
+		) -> DispatchResultWithPostInfo {
 			let who = ensure_signed(origin)?;
 			SavedCalls::<T>::try_mutate_exists(hash, |maybe_call| {
 				let (call, maybe_caller) = maybe_call.take().ok_or(Error::<T>::CallNotAuthorized)?;
@@ -396,7 +399,7 @@ pub mod module {
 				let result = call.dispatch(OriginFor::<T>::root());
 				Self::deposit_event(Event::TriggeredCallBy(hash, who));
 				Self::deposit_event(Event::Dispatched(result.map(|_| ()).map_err(|e| e.error)));
-				Ok(())
+				Ok(Pays::No.into())
 			})
 		}
 	}

authority/src/tests.rs

@@ -5,6 +5,7 @@
 use super::*;
 use frame_support::{
 	assert_noop, assert_ok,
+	dispatch::DispatchErrorWithPostInfo,
 	traits::{schedule::DispatchTime, OriginTrait},
 };
 use frame_system::RawOrigin;
@@ -533,3 +534,36 @@ fn remove_authorized_call_works() {
 		assert_eq!(Authority::saved_calls(&hash), None);
 	});
 }
+
+#[test]
+fn trigger_call_should_be_free_and_operational() {
+	ExtBuilder::default().build().execute_with(|| {
+		let call = Call::System(frame_system::Call::fill_block(Perbill::one()));
+		let hash = <Runtime as frame_system::Config>::Hashing::hash_of(&call);
+		let call_weight_bound = call.get_dispatch_info().weight;
+		let trigger_call = Call::Authority(authority::Call::trigger_call(hash, call_weight_bound));
+
+		assert_ok!(Authority::authorize_call(Origin::root(), Box::new(call), Some(1)));
+
+		// bad caller pays fee
+		assert_eq!(
+			trigger_call.clone().dispatch(Origin::signed(2)),
+			Err(DispatchErrorWithPostInfo {
+				post_info: PostDispatchInfo {
+					actual_weight: None,
+					pays_fee: Pays::Yes
+				},
+				error: Error::<Runtime>::TriggerCallNotPermitted.into()
+			})
+		);
+
+		// successfull call doesn't pay fee
+		assert_eq!(
+			trigger_call.clone().dispatch(Origin::signed(1)),
+			Ok(PostDispatchInfo {
+				actual_weight: None,
+				pays_fee: Pays::No
+			})
+		);
+	});
+}