parachains_common/
pay.rs

1// Copyright (C) Parity Technologies (UK) Ltd.
2// This file is part of Cumulus.
3// SPDX-License-Identifier: Apache-2.0
4
5// Licensed under the Apache License, Version 2.0 (the "License");
6// you may not use this file except in compliance with the License.
7// You may obtain a copy of the License at
8//
9// 	http://www.apache.org/licenses/LICENSE-2.0
10//
11// Unless required by applicable law or agreed to in writing, software
12// distributed under the License is distributed on an "AS IS" BASIS,
13// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14// See the License for the specific language governing permissions and
15// limitations under the License.
16
17use codec::{Decode, DecodeWithMemTracking, Encode, MaxEncodedLen};
18use frame_support::traits::{
19	fungibles,
20	tokens::{PaymentStatus, Preservation},
21};
22use polkadot_runtime_common::impls::VersionedLocatableAsset;
23use sp_runtime::{traits::TypedGet, DispatchError, RuntimeDebug};
24use xcm::latest::prelude::*;
25use xcm_executor::traits::ConvertLocation;
26
27/// Versioned locatable account type which contains both an XCM `location` and `account_id` to
28/// identify an account which exists on some chain.
29#[derive(
30	Encode,
31	Decode,
32	Eq,
33	PartialEq,
34	Clone,
35	RuntimeDebug,
36	scale_info::TypeInfo,
37	MaxEncodedLen,
38	DecodeWithMemTracking,
39)]
40pub enum VersionedLocatableAccount {
41	#[codec(index = 4)]
42	V4 { location: xcm::v4::Location, account_id: xcm::v4::Location },
43	#[codec(index = 5)]
44	V5 { location: xcm::v5::Location, account_id: xcm::v5::Location },
45}
46
47/// Pay on the local chain with `fungibles` implementation if the beneficiary and the asset are both
48/// local.
49pub struct LocalPay<F, A, C>(core::marker::PhantomData<(F, A, C)>);
50impl<A, F, C> frame_support::traits::tokens::Pay for LocalPay<F, A, C>
51where
52	A: TypedGet,
53	F: fungibles::Mutate<A::Type, AssetId = xcm::v5::Location> + fungibles::Create<A::Type>,
54	C: ConvertLocation<A::Type>,
55	A::Type: Eq + Clone,
56{
57	type Balance = F::Balance;
58	type Beneficiary = VersionedLocatableAccount;
59	type AssetKind = VersionedLocatableAsset;
60	type Id = QueryId;
61	type Error = DispatchError;
62	fn pay(
63		who: &Self::Beneficiary,
64		asset: Self::AssetKind,
65		amount: Self::Balance,
66	) -> Result<Self::Id, Self::Error> {
67		let who = Self::match_location(who).map_err(|_| DispatchError::Unavailable)?;
68		let asset = Self::match_asset(&asset).map_err(|_| DispatchError::Unavailable)?;
69		<F as fungibles::Mutate<_>>::transfer(
70			asset,
71			&A::get(),
72			&who,
73			amount,
74			Preservation::Expendable,
75		)?;
76		// We use `QueryId::MAX` as a constant identifier for these payments since they are always
77		// processed immediately and successfully on the local chain. The `QueryId` type is used to
78		// maintain compatibility with XCM payment implementations.
79		Ok(Self::Id::MAX)
80	}
81	fn check_payment(_: Self::Id) -> PaymentStatus {
82		PaymentStatus::Success
83	}
84	#[cfg(feature = "runtime-benchmarks")]
85	fn ensure_successful(_: &Self::Beneficiary, asset: Self::AssetKind, amount: Self::Balance) {
86		let asset = Self::match_asset(&asset).expect("invalid asset");
87		<F as fungibles::Create<_>>::create(asset.clone(), A::get(), true, amount).unwrap();
88		<F as fungibles::Mutate<_>>::mint_into(asset, &A::get(), amount).unwrap();
89	}
90	#[cfg(feature = "runtime-benchmarks")]
91	fn ensure_concluded(_: Self::Id) {}
92}
93
94impl<A, F, C> LocalPay<F, A, C>
95where
96	A: TypedGet,
97	F: fungibles::Mutate<A::Type> + fungibles::Create<A::Type>,
98	C: ConvertLocation<A::Type>,
99	A::Type: Eq + Clone,
100{
101	fn match_location(who: &VersionedLocatableAccount) -> Result<A::Type, ()> {
102		// only applicable for the local accounts
103		let account_id = match who {
104			VersionedLocatableAccount::V4 { location, account_id } if location.is_here() =>
105				&account_id.clone().try_into().map_err(|_| ())?,
106			VersionedLocatableAccount::V5 { location, account_id } if location.is_here() =>
107				account_id,
108			_ => return Err(()),
109		};
110		C::convert_location(account_id).ok_or(())
111	}
112	fn match_asset(asset: &VersionedLocatableAsset) -> Result<xcm::v5::Location, ()> {
113		match asset {
114			VersionedLocatableAsset::V4 { location, asset_id } if location.is_here() =>
115				asset_id.clone().try_into().map(|a: xcm::v5::AssetId| a.0).map_err(|_| ()),
116			VersionedLocatableAsset::V5 { location, asset_id } if location.is_here() =>
117				Ok(asset_id.clone().0),
118			_ => Err(()),
119		}
120	}
121}
122
123#[cfg(feature = "runtime-benchmarks")]
124pub mod benchmarks {
125	use super::*;
126	use core::marker::PhantomData;
127	use frame_support::traits::Get;
128	use pallet_treasury::ArgumentsFactory as TreasuryArgumentsFactory;
129	use sp_core::ConstU8;
130
131	/// Provides factory methods for the `AssetKind` and the `Beneficiary` that are applicable for
132	/// the payout made by [`LocalPay`].
133	///
134	/// ### Parameters:
135	/// - `PalletId`: The ID of the assets registry pallet.
136	/// - `AssetId`: The ID of the asset that will be created for the benchmark within `PalletId`.
137	pub struct LocalPayArguments<PalletId = ConstU8<0>>(PhantomData<PalletId>);
138	impl<PalletId: Get<u8>>
139		TreasuryArgumentsFactory<VersionedLocatableAsset, VersionedLocatableAccount>
140		for LocalPayArguments<PalletId>
141	{
142		fn create_asset_kind(seed: u32) -> VersionedLocatableAsset {
143			VersionedLocatableAsset::V5 {
144				location: Location::new(0, []),
145				asset_id: Location::new(
146					0,
147					[PalletInstance(PalletId::get()), GeneralIndex(seed.into())],
148				)
149				.into(),
150			}
151		}
152		fn create_beneficiary(seed: [u8; 32]) -> VersionedLocatableAccount {
153			VersionedLocatableAccount::V5 {
154				location: Location::new(0, []),
155				account_id: Location::new(0, [AccountId32 { network: None, id: seed }]),
156			}
157		}
158	}
159}
parachains_common/pay.rs

parachains_common/
pay.rs
