Add fee for incoming assets (#385)

* wip first iteration

* fix modified tests

* remove UsingComponents Trader, fix pendulum integration tests with fees

* fix amplitude integration tests to account for xcm fees

* clean imports

* modification of existential deposits closure to handle native as well

* adjust valuations to base everything on native token

* fix test values for new relative values

runtime/amplitude/src/lib.rs

@@ -776,8 +776,14 @@ impl pallet_child_bounties::Config for Runtime {
 }
 
 parameter_type_with_key! {
-	pub ExistentialDeposits: |_currency_id: CurrencyId| -> Balance {
-		NANOUNIT
+	pub ExistentialDeposits: |currency_id: CurrencyId| -> Balance {
+		// Since the xcm trader uses Tokens to get the minimum
+		// balance of both it's assets and native, we need to 
+		// handle native here
+		match currency_id{
+			CurrencyId::Native => EXISTENTIAL_DEPOSIT,
+			_ => NANOUNIT
+		}
 	};
 }
 

runtime/amplitude/src/xcm_config.rs

@@ -3,6 +3,7 @@ use core::marker::PhantomData;
 use frame_support::{
 	log, match_types, parameter_types,
 	traits::{ContainsPair, Everything, Nothing},
+	weights::{Weight, WeightToFee as WeightToFeeTrait},
 };
 use orml_traits::{
 	location::{RelativeReserveProvider, Reserve},
@@ -11,18 +12,26 @@ use orml_traits::{
 use orml_xcm_support::{DepositToAlternative, IsNativeConcrete, MultiCurrencyAdapter};
 use pallet_xcm::XcmPassthrough;
 use polkadot_parachain::primitives::Sibling;
-use polkadot_runtime_common::impls::ToAuthor;
 use sp_runtime::traits::Convert;
 use xcm::latest::{prelude::*, Weight as XCMWeight};
 use xcm_builder::{
-	AccountId32Aliases, AllowUnpaidExecutionFrom, EnsureXcmOrigin, FixedWeightBounds,
-	ParentIsPreset, RelayChainAsNative, SiblingParachainAsNative, SiblingParachainConvertsVia,
-	SignedAccountId32AsNative, SignedToAccountId32, SovereignSignedViaLocation, UsingComponents,
+	AccountId32Aliases, AllowKnownQueryResponses, AllowSubscriptionsFrom,
+	AllowTopLevelPaidExecutionFrom, AllowUnpaidExecutionFrom, ConvertedConcreteId, EnsureXcmOrigin,
+	FixedWeightBounds, ParentIsPreset, RelayChainAsNative, SiblingParachainAsNative,
+	SiblingParachainConvertsVia, SignedAccountId32AsNative, SignedToAccountId32,
+	SovereignSignedViaLocation, TakeWeightCredit,
+};
+use xcm_executor::{
+	traits::{JustTry, ShouldExecute},
+	XcmExecutor,
 };
-use xcm_executor::{traits::ShouldExecute, XcmExecutor};
 
 use runtime_common::parachains::kusama::asset_hub;
 
+use cumulus_primitives_utility::{
+	ChargeWeightInFungibles, TakeFirstAssetTrader, XcmFeesTo32ByteAccount,
+};
+
 use crate::{
 	assets::{
 		native_locations::{native_location_external_pov, native_location_local_pov},
@@ -33,8 +42,8 @@ use crate::{
 
 use super::{
 	AccountId, AmplitudeTreasuryAccount, Balance, Balances, Currencies, CurrencyId, ParachainInfo,
-	ParachainSystem, PolkadotXcm, Runtime, RuntimeCall, RuntimeEvent, RuntimeOrigin, WeightToFee,
-	XcmpQueue,
+	ParachainSystem, PolkadotXcm, Runtime, RuntimeCall, RuntimeEvent, RuntimeOrigin, Tokens,
+	WeightToFee, XcmpQueue,
 };
 
 parameter_types! {
@@ -104,6 +113,38 @@ impl Convert<MultiAsset, Option<CurrencyId>> for CurrencyIdConvert {
 	}
 }
 
+pub struct RelativeValue {
+	num: Balance,
+	denominator: Balance,
+}
+
+impl RelativeValue {
+	fn adjust_amount_by_relative_value(amount: Balance, relative_value: RelativeValue) -> Balance {
+		if relative_value.denominator == 0 {
+			// Or probably error
+			return amount
+		}
+		// Calculate the adjusted amount
+		let adjusted_amount = amount * relative_value.denominator / relative_value.num;
+		adjusted_amount
+	}
+}
+
+pub struct RelayRelativeValue;
+impl RelayRelativeValue {
+	fn get_relative_value(id: CurrencyId) -> Option<RelativeValue> {
+		match id {
+			CurrencyId::XCM(index) => match index {
+				xcm_assets::RELAY_KSM => Some(RelativeValue { num: 100, denominator: 1 }),
+				xcm_assets::ASSETHUB_USDT => Some(RelativeValue { num: 20, denominator: 4 }),
+				_ => None,
+			},
+			CurrencyId::Native => Some(RelativeValue { num: 1, denominator: 1 }),
+			_ => Some(RelativeValue { num: 1, denominator: 1 }),
+		}
+	}
+}
+
 /// Convert an incoming `MultiLocation` into a `CurrencyId` if possible.
 /// Here we need to know the canonical representation of all the tokens we handle in order to
 /// correctly convert their `MultiLocation` representation into our internal `CurrencyId` type.
@@ -244,7 +285,53 @@ impl ShouldExecute for DenyReserveTransferToRelayChain {
 	}
 }
 
-pub type Barrier = AllowUnpaidExecutionFrom<Everything>;
+match_types! {
+	pub type ParentOrParentsPlurality: impl Contains<MultiLocation> = {
+		MultiLocation { parents: 1, interior: Here } |
+		MultiLocation { parents: 1, interior: X1(Plurality { .. }) }
+	};
+}
+
+pub type Barrier = (
+	TakeWeightCredit,
+	AllowTopLevelPaidExecutionFrom<Everything>,
+	// Parent and its plurality get free execution
+	AllowUnpaidExecutionFrom<ParentOrParentsPlurality>,
+	// Expected responses are OK.
+	AllowKnownQueryResponses<PolkadotXcm>,
+	// Subscriptions for version tracking are OK.
+	AllowSubscriptionsFrom<Everything>,
+);
+
+pub struct ChargeWeightInFungiblesImplementation;
+impl ChargeWeightInFungibles<AccountId, Tokens> for ChargeWeightInFungiblesImplementation {
+	fn charge_weight_in_fungibles(
+		asset_id: CurrencyId,
+		weight: Weight,
+	) -> Result<Balance, XcmError> {
+		let amount = <WeightToFee as WeightToFeeTrait>::weight_to_fee(&weight);
+
+		if let Some(relative_value) = RelayRelativeValue::get_relative_value(asset_id) {
+			let adjusted_amount =
+				RelativeValue::adjust_amount_by_relative_value(amount, relative_value);
+			log::info!("amount to be charged: {:?} in asset: {:?}", adjusted_amount, asset_id);
+			return Ok(adjusted_amount)
+		} else {
+			log::info!("amount to be charged: {:?} in asset: {:?}", amount, asset_id);
+			return Ok(amount)
+		}
+	}
+}
+
+pub type Traders = (
+	TakeFirstAssetTrader<
+		AccountId,
+		ChargeWeightInFungiblesImplementation,
+		ConvertedConcreteId<CurrencyId, Balance, CurrencyIdConvert, JustTry>,
+		Tokens,
+		XcmFeesTo32ByteAccount<LocalAssetTransactor, AccountId, AmplitudeTreasuryAccount>,
+	>,
+);
 
 pub struct XcmConfig;
 impl xcm_executor::Config for XcmConfig {
@@ -259,8 +346,7 @@ impl xcm_executor::Config for XcmConfig {
 	type UniversalLocation = UniversalLocation;
 	type Barrier = Barrier;
 	type Weigher = FixedWeightBounds<UnitWeightCost, RuntimeCall, MaxInstructions>;
-	type Trader =
-		UsingComponents<WeightToFee, RelayLocation, AccountId, Balances, ToAuthor<Runtime>>;
+	type Trader = Traders;
 	type ResponseHandler = PolkadotXcm;
 	type AssetTrap = PolkadotXcm;
 	type AssetLocker = ();

runtime/common/src/custom_transactor.rs

@@ -1,21 +1,7 @@
-use sp_runtime::{
-	codec::FullCodec,
-	traits::{Convert, MaybeSerializeDeserialize, SaturatedConversion},
-};
-use sp_std::{
-	cmp::{Eq, PartialEq},
-	fmt::Debug,
-	marker::PhantomData,
-	prelude::*,
-	result,
-};
+use sp_std::{marker::PhantomData, result};
 
-use orml_xcm_support::{OnDepositFail, UnknownAsset as UnknownAssetT};
 use xcm::v3::{prelude::*, Error as XcmError, MultiAsset, MultiLocation, Result};
-use xcm_executor::{
-	traits::{Convert as MoreConvert, MatchesFungible, TransactAsset},
-	Assets,
-};
+use xcm_executor::{traits::TransactAsset, Assets};
 
 pub struct AssetData {
 	pub length: u8,

runtime/foucoco/src/lib.rs

@@ -781,8 +781,14 @@ impl pallet_child_bounties::Config for Runtime {
 }
 
 parameter_type_with_key! {
-	pub ExistentialDeposits: |_currency_id: CurrencyId| -> Balance {
-		NANOUNIT
+	pub ExistentialDeposits: |currency_id: CurrencyId| -> Balance {
+		// Since the xcm trader uses Tokens to get the minimum
+		// balance of both it's assets and native, we need to 
+		// handle native here
+		match currency_id{
+			CurrencyId::Native => EXISTENTIAL_DEPOSIT,
+			_ => NANOUNIT
+		}
 	};
 }
 

runtime/integration-tests/src/amplitude_tests.rs

@@ -2,8 +2,7 @@ use crate::{
 	mock::{kusama_relay_ext, para_ext, ParachainType, USDT_ASSET_ID},
 	sibling,
 	test_macros::{
-		moonbeam_transfers_token_and_handle_automation, parachain1_transfer_asset_to_parachain2,
-		parachain1_transfer_asset_to_parachain2_and_back,
+		parachain1_transfer_asset_to_parachain2, parachain1_transfer_asset_to_parachain2_and_back,
 		parachain1_transfer_incorrect_asset_to_parachain2_should_fail,
 		transfer_10_relay_token_from_parachain_to_relay_chain,
 		transfer_20_relay_token_from_relay_chain_to_parachain,
@@ -17,7 +16,9 @@ use statemine_runtime as kusama_asset_hub_runtime;
 use xcm::latest::NetworkId;
 use xcm_emulator::{decl_test_network, decl_test_parachain, decl_test_relay_chain, TestExt};
 
-const KSM_FEE_WHEN_TRANSFER_TO_PARACHAIN: polkadot_core_primitives::Balance = 3200000000;
+const KSM_FEE_WHEN_TRANSFER_TO_PARACHAIN: polkadot_core_primitives::Balance = 32000000;
+const USDT_FEE_WHEN_TRANSFER_TO_PARACHAIN: polkadot_core_primitives::Balance = 640000000;
+const NATIVE_FEE_WHEN_TRANSFER_TO_PARACHAIN: polkadot_core_primitives::Balance = 3200000000;
 
 decl_test_relay_chain! {
 	pub struct KusamaRelay {
@@ -111,7 +112,8 @@ fn assethub_transfer_asset_to_amplitude() {
 		USDT_ASSET_ID,
 		amplitude_runtime,
 		AmplitudeParachain,
-		AMPLITUDE_ID
+		AMPLITUDE_ID,
+		USDT_FEE_WHEN_TRANSFER_TO_PARACHAIN
 	);
 }
 
@@ -127,7 +129,8 @@ fn assethub_transfer_asset_to_amplitude_and_back() {
 		amplitude_runtime,
 		AmplitudeParachain,
 		AMPLITUDE_ID,
-		network_id
+		network_id,
+		USDT_FEE_WHEN_TRANSFER_TO_PARACHAIN
 	);
 }
 
@@ -140,6 +143,7 @@ fn transfer_native_token_from_amplitude_to_sibling_parachain_and_back() {
 		sibling,
 		SiblingParachain,
 		AMPLITUDE_ID,
-		SIBLING_ID
+		SIBLING_ID,
+		NATIVE_FEE_WHEN_TRANSFER_TO_PARACHAIN
 	);
 }

runtime/integration-tests/src/pendulum_tests.rs

@@ -18,7 +18,10 @@ use statemint_runtime as polkadot_asset_hub_runtime;
 use xcm::latest::NetworkId;
 use xcm_emulator::{decl_test_network, decl_test_parachain, decl_test_relay_chain, TestExt};
 
-const DOT_FEE_WHEN_TRANSFER_TO_PARACHAIN: polkadot_core_primitives::Balance = 3200000000; //The fees that relay chain will charge when transfer DOT to parachain. sovereign account of some parachain will receive transfer_amount - DOT_FEE
+const DOT_FEE_WHEN_TRANSFER_TO_PARACHAIN: polkadot_core_primitives::Balance = 32653061; //The fees that relay chain will charge when transfer DOT to parachain. sovereign account of some parachain will receive transfer_amount - DOT_FEE
+const MOONBEAM_BRZ_FEE_WHEN_TRANSFER_TO_PARACHAIN: polkadot_core_primitives::Balance = 1391304347; //Fees that we will charge in incoming Moonbeam's BRZ. Depends on the RelativeValue struct implementation.
+const USDT_FEE_WHEN_TRANSFER_TO_PARACHAIN: polkadot_core_primitives::Balance = 266666666;
+const NATIVE_FEE_WHEN_TRANSFER_TO_PARACHAIN: polkadot_core_primitives::Balance = 3200000000;
 
 decl_test_relay_chain! {
 	pub struct PolkadotRelay {
@@ -123,7 +126,8 @@ fn assethub_transfer_asset_to_pendulum() {
 		USDT_ASSET_ID,
 		pendulum_runtime,
 		PendulumParachain,
-		PENDULUM_ID
+		PENDULUM_ID,
+		USDT_FEE_WHEN_TRANSFER_TO_PARACHAIN
 	);
 }
 
@@ -139,7 +143,8 @@ fn assethub_transfer_asset_to_pendulum_and_back() {
 		pendulum_runtime,
 		PendulumParachain,
 		PENDULUM_ID,
-		network_id
+		network_id,
+		USDT_FEE_WHEN_TRANSFER_TO_PARACHAIN
 	);
 }
 
@@ -152,7 +157,8 @@ fn transfer_native_token_from_pendulum_to_sibling_parachain_and_back() {
 		sibling,
 		SiblingParachain,
 		PENDULUM_ID,
-		SIBLING_ID
+		SIBLING_ID,
+		NATIVE_FEE_WHEN_TRANSFER_TO_PARACHAIN
 	);
 }
 
@@ -165,6 +171,7 @@ fn moonbeam_transfers_token_and_handle_automation() {
 		sibling,
 		MoonbeamParachain,
 		PENDULUM_ID,
-		MOONBEAM_PARA_ID
+		MOONBEAM_PARA_ID,
+		MOONBEAM_BRZ_FEE_WHEN_TRANSFER_TO_PARACHAIN
 	);
 }