Introduce XcmFeesToAccount fee manager (#1234)

Combination of paritytech/polkadot#7005, its addon PR paritytech/polkadot#7585 and its companion paritytech/cumulus#2433. This PR introduces a new XcmFeesToAccount struct which implements the `FeeManager` trait, and assigns this struct as the `FeeManager` in the XCM config for all runtimes. The struct simply deposits all fees handled by the XCM executor to a specified account. In all runtimes, the specified account is configured as the treasury account. XCM __delivery__ fees are now being introduced (unless the root origin is sending a message to a system parachain on behalf of the originating chain). # Note for reviewers Most file changes are tests that had to be modified to account for the new fees. Main changes are in: - cumulus/pallets/xcmp-queue/src/lib.rs <- To make it track the delivery fees exponential factor - polkadot/xcm/xcm-builder/src/fee_handling.rs <- Added. Has the FeeManager implementation - All runtime xcm_config files <- To add the FeeManager to the XCM configuration # Important note After this change, instructions that create and send a new XCM (Query*, Report*, ExportMessage, InitiateReserveWithdraw, InitiateTeleport, DepositReserveAsset, TransferReserveAsset, LockAsset and RequestUnlock) will require the corresponding origin account in the origin register to pay for transport delivery fees, and the onward message will fail to be sent if the origin account does not have the required amount. This delivery fee is on top of what we already collect as tx fees in pallet-xcm and XCM BuyExecution fees! Wallet UIs that want to expose the new delivery fee can do so using the formula: ``` delivery_fee_factor * (base_fee + encoded_msg_len * per_byte_fee) ``` where the delivery fee factor can be obtained from the corresponding pallet based on which transport you are using (UMP, HRMP or bridges), the base fee is a constant, the encoded message length from the message itself and the per byte fee is the same as the configured per byte fee for txs (i.e. `TransactionByteFee`). --------- Co-authored-by: Branislav Kontur <bkontur@gmail.com> Co-authored-by: joe petrowski <25483142+joepetrowski@users.noreply.github.com> Co-authored-by: Giles Cope <gilescope@gmail.com> Co-authored-by: command-bot <> Co-authored-by: Francisco Aguirre <franciscoaguirreperez@gmail.com> Co-authored-by: Liam Aharon <liam.aharon@hotmail.com> Co-authored-by: Kian Paimani <5588131+kianenigma@users.noreply.github.com>
2026-05-30 14:01:02 +00:00 · 2023-10-18 23:22:25 +08:00
parent 1cf7d3aafa
commit 3dece311be
99 changed files with 2229 additions and 468 deletions
@@ -60,6 +60,7 @@ polkadot-core-primitives = { path = "../../../../../polkadot/core-primitives", d
 polkadot-parachain-primitives = { path = "../../../../../polkadot/parachain", default-features = false}
 polkadot-runtime-common = { path = "../../../../../polkadot/runtime/common", default-features = false}
 westend-runtime-constants = { path = "../../../../../polkadot/runtime/westend/constants", default-features = false}
+westend-runtime = { path = "../../../../../polkadot/runtime/westend", default-features = false }
 xcm = { package = "staging-xcm", path = "../../../../../polkadot/xcm", default-features = false}
 xcm-builder = { package = "staging-xcm-builder", path = "../../../../../polkadot/xcm/xcm-builder", default-features = false}
 xcm-executor = { package = "staging-xcm-executor", path = "../../../../../polkadot/xcm/xcm-executor", default-features = false}
@@ -116,6 +117,7 @@ runtime-benchmarks = [
 	"polkadot-parachain-primitives/runtime-benchmarks",
 	"polkadot-runtime-common/runtime-benchmarks",
 	"sp-runtime/runtime-benchmarks",
+	"westend-runtime/runtime-benchmarks",
 	"xcm-builder/runtime-benchmarks",
 	"xcm-executor/runtime-benchmarks",
 ]
@@ -149,6 +151,7 @@ try-runtime = [
 	"parachain-info/try-runtime",
 	"polkadot-runtime-common/try-runtime",
 	"sp-runtime/try-runtime",
+	"westend-runtime/try-runtime",
 ]
 std = [
 	"assets-common/std",
@@ -210,6 +213,7 @@ std = [
 	"sp-version/std",
 	"substrate-wasm-builder",
 	"westend-runtime-constants/std",
+	"westend-runtime/std",
 	"xcm-builder/std",
 	"xcm-executor/std",
 	"xcm/std",
@@ -88,6 +88,7 @@ use assets_common::{
 	foreign_creators::ForeignCreators, matching::FromSiblingParachain, MultiLocationForAssetId,
 };
 use polkadot_runtime_common::{BlockHashCount, SlowAdjustingFeeUpdate};
+use xcm::latest::prelude::*;
 use xcm_executor::XcmExecutor;

 use crate::xcm_config::ForeignCreatorsSovereignAccountOf;
@@ -604,6 +605,20 @@ impl parachain_info::Config for Runtime {}

 impl cumulus_pallet_aura_ext::Config for Runtime {}

+parameter_types! {
+	/// The asset ID for the asset that we use to pay for message delivery fees.
+	pub FeeAssetId: AssetId = Concrete(xcm_config::WestendLocation::get());
+	/// The base fee for the message delivery fees.
+	pub const BaseDeliveryFee: u128 = CENTS.saturating_mul(3);
+}
+
+pub type PriceForSiblingParachainDelivery = polkadot_runtime_common::xcm_sender::ExponentialPrice<
+	FeeAssetId,
+	BaseDeliveryFee,
+	TransactionByteFee,
+	XcmpQueue,
+>;
+
 impl cumulus_pallet_xcmp_queue::Config for Runtime {
 	type RuntimeEvent = RuntimeEvent;
 	type XcmExecutor = XcmExecutor<XcmConfig>;
@@ -613,7 +628,7 @@ impl cumulus_pallet_xcmp_queue::Config for Runtime {
 	type ControllerOrigin = EnsureRoot<AccountId>;
 	type ControllerOriginConverter = XcmOriginToTransactDispatchOrigin;
 	type WeightInfo = weights::cumulus_pallet_xcmp_queue::WeightInfo<Runtime>;
-	type PriceForSiblingDelivery = ();
+	type PriceForSiblingDelivery = PriceForSiblingParachainDelivery;
 }

 impl cumulus_pallet_dmp_queue::Config for Runtime {
@@ -1262,9 +1277,21 @@ impl_runtime_apis! {
 			use xcm_config::{MaxAssetsIntoHolding, WestendLocation};
 			use pallet_xcm_benchmarks::asset_instance_from;

+			parameter_types! {
+				pub ExistentialDepositMultiAsset: Option<MultiAsset> = Some((
+					WestendLocation::get(),
+					ExistentialDeposit::get()
+				).into());
+			}
+
 			impl pallet_xcm_benchmarks::Config for Runtime {
 				type XcmConfig = xcm_config::XcmConfig;
 				type AccountIdConverter = xcm_config::LocationToAccountId;
+				type DeliveryHelper = cumulus_primitives_utility::ToParentDeliveryHelper<
+					XcmConfig,
+					ExistentialDepositMultiAsset,
+					xcm_config::PriceForParentDelivery,
+				>;
 				fn valid_destination() -> Result<MultiLocation, BenchmarkError> {
 					Ok(WestendLocation::get())
 				}
@@ -1320,6 +1347,7 @@ impl_runtime_apis! {
 			}

 			impl pallet_xcm_benchmarks::generic::Config for Runtime {
+				type TransactAsset = Balances;
 				type RuntimeCall = RuntimeCall;

 				fn worst_case_response() -> (u64, Response) {
@@ -1421,7 +1449,6 @@ pub mod migrations {
 	};
 	use parachains_common::impls::AccountIdOf;
 	use sp_runtime::{traits::StaticLookup, Saturating};
-	use xcm::latest::prelude::*;

 	/// Temporary migration because of bug with native asset, it can be removed once applied on
 	/// `AssetHubWestend`. Migrates pools with `MultiLocation { parents: 0, interior: Here }` to
@@ -14,9 +14,10 @@
 // limitations under the License.

 use super::{
-	AccountId, AllPalletsWithSystem, Assets, Authorship, Balance, Balances, ParachainInfo,
-	ParachainSystem, PolkadotXcm, PoolAssets, Runtime, RuntimeCall, RuntimeEvent, RuntimeOrigin,
-	TrustBackedAssetsInstance, WeightToFee, XcmpQueue,
+	AccountId, AllPalletsWithSystem, Assets, Authorship, Balance, Balances, BaseDeliveryFee,
+	FeeAssetId, ParachainInfo, ParachainSystem, PolkadotXcm, PoolAssets, Runtime, RuntimeCall,
+	RuntimeEvent, RuntimeOrigin, TransactionByteFee, TrustBackedAssetsInstance, WeightToFee,
+	XcmpQueue,
 };
 use crate::ForeignAssets;
 use assets_common::{
@@ -31,10 +32,17 @@ use frame_system::EnsureRoot;
 use pallet_xcm::XcmPassthrough;
 use parachains_common::{
 	impls::ToStakingPot,
-	xcm_config::{AssetFeeAsExistentialDepositMultiplier, ConcreteAssetFromSystem},
+	xcm_config::{
+		AssetFeeAsExistentialDepositMultiplier, ConcreteAssetFromSystem,
+		RelayOrOtherSystemParachains,
+	},
+	TREASURY_PALLET_ID,
 };
 use polkadot_parachain_primitives::primitives::Sibling;
-use sp_runtime::traits::ConvertInto;
+use polkadot_runtime_common::xcm_sender::ExponentialPrice;
+use sp_runtime::traits::{AccountIdConversion, ConvertInto};
+use westend_runtime::Treasury as WestendTreasury;
+use westend_runtime_constants::system_parachain;
 use xcm::latest::prelude::*;
 use xcm_builder::{
 	AccountId32Aliases, AllowExplicitUnpaidExecutionFrom, AllowKnownQueryResponses,
@@ -45,6 +53,7 @@ use xcm_builder::{
 	SiblingParachainConvertsVia, SignedAccountId32AsNative, SignedToAccountId32,
 	SovereignSignedViaLocation, StartsWith, StartsWithExplicitGlobalConsensus, TakeWeightCredit,
 	TrailingSetTopicAsId, UsingComponents, WeightInfoBounds, WithComputedOrigin, WithUniqueTopic,
+	XcmFeesToAccount,
 };
 use xcm_executor::{traits::WithOriginFilter, XcmExecutor};

@@ -65,6 +74,7 @@ parameter_types! {
 	pub PoolAssetsPalletLocation: MultiLocation =
 		PalletInstance(<PoolAssets as PalletInfoAccess>::index() as u8).into();
 	pub CheckingAccount: AccountId = PolkadotXcm::check_account();
+	pub TreasuryAccount: Option<AccountId> = Some(TREASURY_PALLET_ID.into_account_truncating());
 }

 /// Type for specifying how a `MultiLocation` can be converted into an `AccountId`. This is used
@@ -482,6 +492,36 @@ pub type AssetFeeAsExistentialDepositMultiplierFeeCharger = AssetFeeAsExistentia
 	TrustBackedAssetsInstance,
 >;

+match_types! {
+	pub type SystemParachains: impl Contains<MultiLocation> = {
+		MultiLocation {
+			parents: 1,
+			interior: X1(Parachain(
+				system_parachain::ASSET_HUB_ID |
+				system_parachain::COLLECTIVES_ID |
+				system_parachain::BRIDGE_HUB_ID
+			)),
+		}
+	};
+}
+
+parameter_types! {
+	pub RelayTreasuryLocation: MultiLocation = (Parent, PalletInstance(<WestendTreasury as PalletInfoAccess>::index() as u8)).into();
+}
+
+pub struct RelayTreasury;
+impl Contains<MultiLocation> for RelayTreasury {
+	fn contains(location: &MultiLocation) -> bool {
+		let relay_treasury_location = RelayTreasuryLocation::get();
+		*location == relay_treasury_location
+	}
+}
+
+/// Locations that will not be charged fees in the executor,
+/// either execution or delivery.
+/// We only waive fees for system functions, which these locations represent.
+pub type WaivedLocations = (RelayOrOtherSystemParachains<SystemParachains, Runtime>, RelayTreasury);
+
 /// Cases where a remote origin is accepted as trusted Teleporter for a given asset:
 ///
 /// - WND with the parent Relay Chain and sibling system parachains; and
@@ -531,7 +571,7 @@ impl xcm_executor::Config for XcmConfig {
 	type MaxAssetsIntoHolding = MaxAssetsIntoHolding;
 	type AssetLocker = ();
 	type AssetExchanger = ();
-	type FeeManager = ();
+	type FeeManager = XcmFeesToAccount<Self, WaivedLocations, AccountId, TreasuryAccount>;
 	type MessageExporter = ();
 	type UniversalAliases = Nothing;
 	type CallDispatcher = WithOriginFilter<SafeCallFilter>;
@@ -542,11 +582,14 @@ impl xcm_executor::Config for XcmConfig {
 /// Local origins on this chain are allowed to dispatch XCM sends/executions.
 pub type LocalOriginToLocation = SignedToAccountId32<RuntimeOrigin, AccountId, RelayNetwork>;

+pub type PriceForParentDelivery =
+	ExponentialPrice<FeeAssetId, BaseDeliveryFee, TransactionByteFee, ParachainSystem>;
+
 /// The means for routing XCM messages which are not for local execution into the right message
 /// queues.
 pub type XcmRouter = WithUniqueTopic<(
 	// Two routers - use UMP to communicate with the relay chain:
-	cumulus_primitives_utility::ParentAsUmp<ParachainSystem, PolkadotXcm, ()>,
+	cumulus_primitives_utility::ParentAsUmp<ParachainSystem, PolkadotXcm, PriceForParentDelivery>,
 	// ..and XCMP to communicate with the sibling chains.
 	XcmpQueue,
 )>;