Companion for #13352

Cargo.toml

@@ -35,6 +35,7 @@ members = [
 	"parachains/runtimes/testing/rococo-parachain",
 	"parachains/runtimes/starters/shell",
 	"parachains/runtimes/starters/seedling",
+	"parachains/runtimes/assets/common",
 	"parachains/runtimes/assets/statemint",
 	"parachains/runtimes/assets/statemine",
 	"parachains/runtimes/assets/westmint",

parachains/runtimes/assets/common/Cargo.toml

@@ -0,0 +1,38 @@
+[package]
+name = "assets-common"
+version = "0.1.0"
+authors = ["Parity Technologies <admin@parity.io>"]
+edition = "2021"
+description = "Assets common utilities"
+
+[dependencies]
+codec = { package = "parity-scale-codec", version = "3.0.0", default-features = false, features = ["derive"] }
+
+# Substrate
+frame-support = { git = "https://github.com/paritytech/substrate", default-features = false, branch = "master" }
+sp-api = { git = "https://github.com/paritytech/substrate", default-features = false, branch = "master" }
+sp-std = { git = "https://github.com/paritytech/substrate", default-features = false, branch = "master" }
+
+# Polkadot
+xcm = { git = "https://github.com/paritytech/polkadot", default-features = false, branch = "master" }
+xcm-builder = { git = "https://github.com/paritytech/polkadot", default-features = false, branch = "master" }
+xcm-executor = { git = "https://github.com/paritytech/polkadot", default-features = false, branch = "master" }
+
+# Cumulus
+parachains-common = { path = "../../../common", default-features = false }
+
+[build-dependencies]
+substrate-wasm-builder = { git = "https://github.com/paritytech/substrate", branch = "master" }
+
+[features]
+default = [ "std" ]
+std = [
+	"codec/std",
+	"frame-support/std",
+	"parachains-common/std",
+	"sp-api/std",
+	"sp-std/std",
+	"xcm/std",
+	"xcm-builder/std",
+	"xcm-executor/std",
+]

parachains/runtimes/assets/common/src/fungible_conversion.rs

@@ -0,0 +1,136 @@
+// This file is part of Substrate.
+
+// Copyright (C) 2018-2022 Parity Technologies (UK) Ltd.
+// SPDX-License-Identifier: GPL-3.0-or-later WITH Classpath-exception-2.0
+
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with this program. If not, see <https://www.gnu.org/licenses/>.
+
+//! Runtime API definition for assets.
+
+use crate::runtime_api::FungiblesAccessError;
+use sp_std::{borrow::Borrow, vec::Vec};
+use xcm::latest::{MultiAsset, MultiLocation};
+use xcm_builder::ConvertedConcreteId;
+use xcm_executor::traits::{Convert, MatchesFungibles};
+
+/// Converting any [`(AssetId, Balance)`] to [`MultiAsset`]
+pub trait MultiAssetConverter<AssetId, Balance, ConvertAssetId, ConvertBalance>:
+	MatchesFungibles<AssetId, Balance>
+where
+	AssetId: Clone,
+	Balance: Clone,
+	ConvertAssetId: Convert<MultiLocation, AssetId>,
+	ConvertBalance: Convert<u128, Balance>,
+{
+	fn convert_ref(
+		value: impl Borrow<(AssetId, Balance)>,
+	) -> Result<MultiAsset, FungiblesAccessError>;
+}
+
+impl<
+		AssetId: Clone,
+		Balance: Clone,
+		ConvertAssetId: Convert<MultiLocation, AssetId>,
+		ConvertBalance: Convert<u128, Balance>,
+	> MultiAssetConverter<AssetId, Balance, ConvertAssetId, ConvertBalance>
+	for ConvertedConcreteId<AssetId, Balance, ConvertAssetId, ConvertBalance>
+{
+	fn convert_ref(
+		value: impl Borrow<(AssetId, Balance)>,
+	) -> Result<MultiAsset, FungiblesAccessError> {
+		let (asset_id, balance) = value.borrow();
+		match ConvertAssetId::reverse_ref(asset_id) {
+			Ok(asset_id_as_multilocation) => match ConvertBalance::reverse_ref(balance) {
+				Ok(amount) => Ok((asset_id_as_multilocation, amount).into()),
+				Err(_) => Err(FungiblesAccessError::AmountToBalanceConversionFailed),
+			},
+			Err(_) => Err(FungiblesAccessError::AssetIdConversionFailed),
+		}
+	}
+}
+
+/// Helper function to convert collections with [`(AssetId, Balance)`] to [`MultiAsset`]
+pub fn convert<'a, AssetId, Balance, ConvertAssetId, ConvertBalance, Converter>(
+	items: impl Iterator<Item = &'a (AssetId, Balance)>,
+) -> Result<Vec<MultiAsset>, FungiblesAccessError>
+where
+	AssetId: Clone + 'a,
+	Balance: Clone + 'a,
+	ConvertAssetId: Convert<MultiLocation, AssetId>,
+	ConvertBalance: Convert<u128, Balance>,
+	Converter: MultiAssetConverter<AssetId, Balance, ConvertAssetId, ConvertBalance>,
+{
+	items.map(Converter::convert_ref).collect()
+}
+
+/// Helper function to convert `Balance` with MultiLocation` to `MultiAsset`
+pub fn convert_balance<
+	T: frame_support::pallet_prelude::Get<MultiLocation>,
+	Balance: TryInto<u128>,
+>(
+	balance: Balance,
+) -> Result<MultiAsset, FungiblesAccessError> {
+	match balance.try_into() {
+		Ok(balance) => Ok((T::get(), balance).into()),
+		Err(_) => Err(FungiblesAccessError::AmountToBalanceConversionFailed),
+	}
+}
+
+#[cfg(test)]
+mod tests {
+	use super::*;
+
+	use xcm::latest::prelude::*;
+	use xcm_executor::traits::{Identity, JustTry};
+
+	type Converter = ConvertedConcreteId<MultiLocation, u64, Identity, JustTry>;
+
+	#[test]
+	fn converted_concrete_id_fungible_multi_asset_conversion_roundtrip_works() {
+		let location = MultiLocation::new(0, X1(GlobalConsensus(ByGenesis([0; 32]))));
+		let amount = 123456_u64;
+		let expected_multi_asset = MultiAsset {
+			id: Concrete(MultiLocation::new(0, X1(GlobalConsensus(ByGenesis([0; 32]))))),
+			fun: Fungible(123456_u128),
+		};
+
+		assert_eq!(
+			Converter::matches_fungibles(&expected_multi_asset).map_err(|_| ()),
+			Ok((location, amount))
+		);
+
+		assert_eq!(Converter::convert_ref((location, amount)), Ok(expected_multi_asset));
+	}
+
+	#[test]
+	fn converted_concrete_id_fungible_multi_asset_conversion_collection_works() {
+		let data = vec![
+			(MultiLocation::new(0, X1(GlobalConsensus(ByGenesis([0; 32])))), 123456_u64),
+			(MultiLocation::new(1, X1(GlobalConsensus(ByGenesis([1; 32])))), 654321_u64),
+		];
+
+		let expected_data = vec![
+			MultiAsset {
+				id: Concrete(MultiLocation::new(0, X1(GlobalConsensus(ByGenesis([0; 32]))))),
+				fun: Fungible(123456_u128),
+			},
+			MultiAsset {
+				id: Concrete(MultiLocation::new(1, X1(GlobalConsensus(ByGenesis([1; 32]))))),
+				fun: Fungible(654321_u128),
+			},
+		];
+
+		assert_eq!(convert::<_, _, _, _, Converter>(data.iter()), Ok(expected_data));
+	}
+}

parachains/runtimes/assets/common/src/lib.rs

@@ -0,0 +1,70 @@
+// Copyright (C) 2023 Parity Technologies (UK) Ltd.
+// SPDX-License-Identifier: Apache-2.0
+
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 	http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#![cfg_attr(not(feature = "std"), no_std)]
+
+pub mod fungible_conversion;
+pub mod runtime_api;
+
+use parachains_common::AssetIdForTrustBackedAssets;
+use xcm_builder::{AsPrefixedGeneralIndex, ConvertedConcreteId};
+use xcm_executor::traits::JustTry;
+
+/// `MultiLocation` vs `AssetIdForTrustBackedAssets` converter for `TrustBackedAssets`
+pub type AssetIdForTrustBackedAssetsConvert<TrustBackedAssetsPalletLocation> =
+	AsPrefixedGeneralIndex<TrustBackedAssetsPalletLocation, AssetIdForTrustBackedAssets, JustTry>;
+
+/// [`ConvertedConcreteId`] converter dedicated for `TrustBackedAssets`
+pub type TrustBackedAssetsConvertedConcreteId<TrustBackedAssetsPalletLocation, Balance> =
+	ConvertedConcreteId<
+		AssetIdForTrustBackedAssets,
+		Balance,
+		AssetIdForTrustBackedAssetsConvert<TrustBackedAssetsPalletLocation>,
+		JustTry,
+	>;
+
+#[cfg(test)]
+mod tests {
+
+	use super::*;
+	use xcm::latest::prelude::*;
+	use xcm_executor::traits::Convert;
+
+	frame_support::parameter_types! {
+		pub TrustBackedAssetsPalletLocation: MultiLocation = MultiLocation::new(5, X1(PalletInstance(13)));
+	}
+
+	#[test]
+	fn asset_id_for_trust_backed_assets_convert_works() {
+		let local_asset_id = 123456789 as AssetIdForTrustBackedAssets;
+		let expected_reverse_ref =
+			MultiLocation::new(5, X2(PalletInstance(13), GeneralIndex(local_asset_id.into())));
+
+		assert_eq!(
+			AssetIdForTrustBackedAssetsConvert::<TrustBackedAssetsPalletLocation>::reverse_ref(
+				local_asset_id
+			)
+			.unwrap(),
+			expected_reverse_ref
+		);
+		assert_eq!(
+			AssetIdForTrustBackedAssetsConvert::<TrustBackedAssetsPalletLocation>::convert_ref(
+				expected_reverse_ref
+			)
+			.unwrap(),
+			local_asset_id
+		);
+	}
+}

parachains/runtimes/assets/common/src/runtime_api.rs

@@ -0,0 +1,41 @@
+// Copyright (C) 2023 Parity Technologies (UK) Ltd.
+// SPDX-License-Identifier: Apache-2.0
+
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 	http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//! Runtime API definition for fungibles.
+
+use codec::{Codec, Decode, Encode};
+use frame_support::RuntimeDebug;
+use sp_std::vec::Vec;
+use xcm::latest::MultiAsset;
+
+/// The possible errors that can happen querying the storage of assets.
+#[derive(Eq, PartialEq, Encode, Decode, RuntimeDebug)]
+pub enum FungiblesAccessError {
+	/// `MultiLocation` to `AssetId`/`ClassId` conversion failed.
+	AssetIdConversionFailed,
+	/// `u128` amount to currency `Balance` conversion failed.
+	AmountToBalanceConversionFailed,
+}
+
+sp_api::decl_runtime_apis! {
+	/// The API for querying account's balances from runtime.
+	pub trait FungiblesApi<AccountId>
+	where
+		AccountId: Codec,
+	{
+		/// Returns the list of all [`MultiAsset`] that an `AccountId` has.
+		fn query_account_balances(account: AccountId) -> Result<Vec<MultiAsset>, FungiblesAccessError>;
+	}
+}

parachains/runtimes/assets/statemine/Cargo.toml

@@ -49,6 +49,7 @@ pallet-state-trie-migration = { git = "https://github.com/paritytech/substrate",
 # Polkadot
 kusama-runtime-constants = { git = "https://github.com/paritytech/polkadot", default-features = false, branch = "master" }
 pallet-xcm = { git = "https://github.com/paritytech/polkadot", default-features = false, branch = "master" }
+pallet-xcm-benchmarks = { git = "https://github.com/paritytech/polkadot", branch = "master", default-features = false, optional = true }
 polkadot-core-primitives = { git = "https://github.com/paritytech/polkadot", default-features = false, branch = "master" }
 polkadot-parachain = { git = "https://github.com/paritytech/polkadot", default-features = false, branch = "master" }
 polkadot-runtime-common = { git = "https://github.com/paritytech/polkadot", default-features = false, branch = "master" }
@@ -69,8 +70,7 @@ cumulus-primitives-utility = { path = "../../../../primitives/utility", default-
 pallet-collator-selection = { path = "../../../../pallets/collator-selection", default-features = false }
 parachain-info = { path = "../../../pallets/parachain-info", default-features = false }
 parachains-common = { path = "../../../common", default-features = false }
-pallet-xcm-benchmarks = { git = "https://github.com/paritytech/polkadot", branch = "master", default-features = false, optional = true }
-
+assets-common = { path = "../common", default-features = false }
 
 [dev-dependencies]
 asset-test-utils = { path = "../test-utils"}
@@ -187,4 +187,5 @@ std = [
 	"pallet-collator-selection/std",
 	"parachain-info/std",
 	"parachains-common/std",
+	"assets-common/std",
 ]

parachains/runtimes/assets/statemine/src/lib.rs

@@ -64,7 +64,7 @@ use parachains_common::{
 	Index, Signature, AVERAGE_ON_INITIALIZE_RATIO, HOURS, MAXIMUM_BLOCK_WEIGHT,
 	NORMAL_DISPATCH_RATIO, SLOT_DURATION,
 };
-use xcm_config::{KsmLocation, XcmConfig};
+use xcm_config::{KsmLocation, TrustBackedAssetsConvertedConcreteId, XcmConfig};
 
 #[cfg(any(feature = "std", test))]
 pub use sp_runtime::BuildStorage;
@@ -831,6 +831,34 @@ impl_runtime_apis! {
 		}
 	}
 
+	impl assets_common::runtime_api::FungiblesApi<
+		Block,
+		AccountId,
+	> for Runtime
+	{
+		fn query_account_balances(account: AccountId) -> Result<Vec<xcm::latest::MultiAsset>, assets_common::runtime_api::FungiblesAccessError> {
+			use assets_common::fungible_conversion::{convert, convert_balance};
+			Ok([
+				// collect pallet_balance
+				{
+					let balance = Balances::free_balance(account.clone());
+					if balance > 0 {
+						vec![convert_balance::<KsmLocation, Balance>(balance)?]
+					} else {
+						vec![]
+					}
+				},
+				// collect pallet_assets (TrustBackedAssets)
+				convert::<_, _, _, _, TrustBackedAssetsConvertedConcreteId>(
+					Assets::account_balances(account)
+						.iter()
+						.filter(|(_, balance)| balance > &0)
+				)?,
+				// collect ... e.g. pallet_assets ForeignAssets
+			].concat())
+		}
+	}
+
 	impl cumulus_primitives_core::CollectCollationInfo<Block> for Runtime {
 		fn collect_collation_info(header: &<Block as BlockT>::Header) -> cumulus_primitives_core::CollationInfo {
 			ParachainSystem::collect_collation_info(header)