Use Contains rather than StaticLookup

parachain/pallets/outbound-queue/src/lib.rs

@@ -94,12 +94,12 @@ use bridge_hub_common::{AggregateMessageOrigin, CustomDigestItem};
 use codec::Decode;
 use frame_support::{
 	storage::StorageStreamIter,
-	traits::{tokens::Balance, Defensive, EnqueueMessage, Get, ProcessMessageError},
+	traits::{tokens::Balance, Contains, Defensive, EnqueueMessage, Get, ProcessMessageError},
 	weights::{Weight, WeightToFee},
 };
 use snowbridge_core::{
 	outbound::{Fee, GasMeter, QueuedMessage, VersionedQueuedMessage, ETHER_DECIMALS},
-	BasicOperatingMode, Channel, ChannelId, StaticLookup,
+	BasicOperatingMode, ChannelId,
 };
 use snowbridge_outbound_queue_merkle_tree::merkle_root;
 pub use snowbridge_outbound_queue_merkle_tree::MerkleProof;
@@ -150,8 +150,8 @@ pub mod pallet {
 		#[pallet::constant]
 		type MaxMessagesPerBlock: Get<u32>;
 
-		/// Lookup a channel descriptor
-		type ChannelLookup: StaticLookup<Source = ChannelId, Target = Channel>;
+		/// Check whether a channel exists
+		type Channels: Contains<ChannelId>;
 
 		type PricingParameters: Get<PricingParameters<Self::Balance>>;
 

parachain/pallets/outbound-queue/src/mock.rs

@@ -4,16 +4,15 @@ use super::*;
 
 use frame_support::{
 	parameter_types,
-	traits::{Everything, Hooks},
+	traits::{Contains, Everything, Hooks},
 	weights::IdentityFee,
 };
 
-use hex_literal::hex;
 use snowbridge_core::{
 	gwei, meth,
 	outbound::*,
 	pricing::{PricingParameters, Rewards},
-	Channel, ParaId, StaticLookup, PRIMARY_GOVERNANCE_CHANNEL,
+	ParaId, PRIMARY_GOVERNANCE_CHANNEL,
 };
 use sp_core::{ConstU32, ConstU8, H160, H256};
 use sp_runtime::{
@@ -94,13 +93,10 @@ parameter_types! {
 
 pub const DOT: u128 = 10_000_000_000;
 
-pub struct MockChannelLookup;
-impl StaticLookup for MockChannelLookup {
-	type Source = ChannelId;
-	type Target = Channel;
-
-	fn lookup(channel_id: Self::Source) -> Option<Self::Target> {
-		Some(Channel { agent_id: H256::zero(), para_id: 0.into() })
+pub struct MockChannels;
+impl Contains<ChannelId> for MockChannels {
+	fn contains(_: &ChannelId) -> bool {
+		true
 	}
 }
 
@@ -114,7 +110,7 @@ impl crate::Config for Test {
 	type GasMeter = ConstantGasMeter;
 	type Balance = u128;
 	type PricingParameters = Parameters;
-	type ChannelLookup = MockChannelLookup;
+	type Channels = MockChannels;
 	type WeightToFee = IdentityFee<u128>;
 	type WeightInfo = ();
 }

parachain/pallets/outbound-queue/src/send_message_impl.rs

@@ -49,7 +49,7 @@ where
 		);
 
 		// Ensure there is a registered channel we can transmit this message on
-		ensure!(T::ChannelLookup::lookup(message.channel_id).is_some(), SendError::InvalidChannel);
+		ensure!(T::Channels::contains(&message.channel_id), SendError::InvalidChannel);
 
 		// Generate a unique message id unless one is provided
 		let message_id: H256 = message

parachain/pallets/system/src/lib.rs

@@ -57,7 +57,7 @@ use frame_support::{
 	traits::{
 		fungible::{Inspect, Mutate},
 		tokens::Preservation,
-		EnsureOrigin,
+		Contains, EnsureOrigin,
 	},
 };
 use frame_system::pallet_prelude::*;
@@ -653,6 +653,12 @@ pub mod pallet {
 		}
 	}
 
+	impl<T: Config> Contains<ChannelId> for Pallet<T> {
+		fn contains(channel_id: &ChannelId) -> bool {
+			Channels::<T>::get(channel_id).is_some()
+		}
+	}
+
 	impl<T: Config> Get<PricingParametersOf<T>> for Pallet<T> {
 		fn get() -> PricingParametersOf<T> {
 			PricingParameters::<T>::get()

parachain/pallets/system/src/mock.rs

@@ -178,7 +178,7 @@ impl snowbridge_outbound_queue::Config for Test {
 	type GasMeter = ConstantGasMeter;
 	type Balance = u128;
 	type PricingParameters = EthereumSystem;
-	type ChannelLookup = EthereumSystem;
+	type Channels = EthereumSystem;
 	type WeightToFee = IdentityFee<u128>;
 	type WeightInfo = ();
 }