Enable cross-chain NFT transfers on asset-hub (#2796)

This PR introduces the following changes:

- [x] Adds a `UniquesTransactor` to asset-hub-rococo
- [x] Adds a `UniquesTransactor` to asset-hub-westend

We can't add a transactor for `pallet-nfts` like we do for
`pallet-uniques` because `pallet-nfts` uses `nonfungibles_v2::Mutate`
instead of `nonfungibles::Mutate`, and making that work would be out of
scope of this PR.

With these modifications, reserve-based NFT cross-chain transfers can be
performed on asset-hub.

---------

Co-authored-by: joe petrowski <25483142+joepetrowski@users.noreply.github.com>

cumulus/parachains/common/src/lib.rs

@@ -67,6 +67,12 @@ mod types {
 
 	// Id used for identifying assets.
 	pub type AssetIdForTrustBackedAssets = u32;
+
+	// Id used for identifying non-fungible collections.
+	pub type CollectionId = u32;
+
+	// Id used for identifying non-fungible items.
+	pub type ItemId = u32;
 }
 
 /// Common constants of parachains.

cumulus/parachains/runtimes/assets/asset-hub-rococo/src/lib.rs

@@ -76,9 +76,9 @@ use parachains_common::{
 	impls::DealWithFees,
 	message_queue::{NarrowOriginToSibling, ParaIdToSibling},
 	rococo::{consensus::*, currency::*, fee::WeightToFee},
-	AccountId, AssetIdForTrustBackedAssets, AuraId, Balance, BlockNumber, Hash, Header, Nonce,
+	AccountId, AssetIdForTrustBackedAssets, AuraId, Balance, BlockNumber, CollectionId, Hash,
-	Signature, AVERAGE_ON_INITIALIZE_RATIO, DAYS, HOURS, MAXIMUM_BLOCK_WEIGHT,
+	Header, ItemId, Nonce, Signature, AVERAGE_ON_INITIALIZE_RATIO, DAYS, HOURS,
-	NORMAL_DISPATCH_RATIO, SLOT_DURATION,
+	MAXIMUM_BLOCK_WEIGHT, NORMAL_DISPATCH_RATIO, SLOT_DURATION,
 };
 use sp_runtime::{Perbill, RuntimeDebug};
 use xcm_config::{
@@ -773,8 +773,8 @@ parameter_types! {
 
 impl pallet_uniques::Config for Runtime {
 	type RuntimeEvent = RuntimeEvent;
-	type CollectionId = u32;
+	type CollectionId = CollectionId;
-	type ItemId = u32;
+	type ItemId = ItemId;
 	type Currency = Balances;
 	type ForceOrigin = AssetsForceOrigin;
 	type CollectionDeposit = UniquesCollectionDeposit;
@@ -831,8 +831,8 @@ parameter_types! {
 
 impl pallet_nfts::Config for Runtime {
 	type RuntimeEvent = RuntimeEvent;
-	type CollectionId = u32;
+	type CollectionId = CollectionId;
-	type ItemId = u32;
+	type ItemId = ItemId;
 	type Currency = Balances;
 	type CreateOrigin = AsEnsureOriginWithArg<EnsureSigned<AccountId>>;
 	type ForceOrigin = AssetsForceOrigin;

cumulus/parachains/runtimes/assets/asset-hub-rococo/src/xcm_config.rs

@@ -17,7 +17,8 @@ use super::{
 	AccountId, AllPalletsWithSystem, Assets, Authorship, Balance, Balances, BaseDeliveryFee,
 	CollatorSelection, FeeAssetId, ForeignAssets, ForeignAssetsInstance, ParachainInfo,
 	ParachainSystem, PolkadotXcm, PoolAssets, Runtime, RuntimeCall, RuntimeEvent, RuntimeOrigin,
-	ToWestendXcmRouter, TransactionByteFee, TrustBackedAssetsInstance, WeightToFee, XcmpQueue,
+	ToWestendXcmRouter, TransactionByteFee, TrustBackedAssetsInstance, Uniques, WeightToFee,
+	XcmpQueue,
 };
 use assets_common::{
 	local_and_foreign_assets::MatchesLocalAndForeignAssetsLocation,
@@ -54,12 +55,12 @@ use xcm_builder::{
 	AllowSubscriptionsFrom, AllowTopLevelPaidExecutionFrom, DenyReserveTransferToRelayChain,
 	DenyThenTry, DescribeAllTerminal, DescribeFamily, EnsureXcmOrigin, FungiblesAdapter,
 	GlobalConsensusParachainConvertsFor, HashedDescription, IsConcrete, LocalMint,
-	NetworkExportTableItem, NoChecking, ParentAsSuperuser, ParentIsPreset, RelayChainAsNative,
+	NetworkExportTableItem, NoChecking, NonFungiblesAdapter, ParentAsSuperuser, ParentIsPreset,
-	SiblingParachainAsNative, SiblingParachainConvertsVia, SignedAccountId32AsNative,
+	RelayChainAsNative, SiblingParachainAsNative, SiblingParachainConvertsVia,
-	SignedToAccountId32, SovereignPaidRemoteExporter, SovereignSignedViaLocation, StartsWith,
+	SignedAccountId32AsNative, SignedToAccountId32, SovereignPaidRemoteExporter,
-	StartsWithExplicitGlobalConsensus, TakeWeightCredit, TrailingSetTopicAsId, UsingComponents,
+	SovereignSignedViaLocation, StartsWith, StartsWithExplicitGlobalConsensus, TakeWeightCredit,
-	WeightInfoBounds, WithComputedOrigin, WithUniqueTopic, XcmFeeManagerFromComponents,
+	TrailingSetTopicAsId, UsingComponents, WeightInfoBounds, WithComputedOrigin, WithUniqueTopic,
-	XcmFeeToAccount,
+	XcmFeeManagerFromComponents, XcmFeeToAccount,
 };
 use xcm_executor::{traits::WithOriginFilter, XcmExecutor};
 
@@ -80,6 +81,8 @@ parameter_types! {
 		PalletInstance(<ForeignAssets as PalletInfoAccess>::index() as u8).into();
 	pub PoolAssetsPalletLocation: Location =
 		PalletInstance(<PoolAssets as PalletInfoAccess>::index() as u8).into();
+	pub UniquesPalletLocation: Location =
+		PalletInstance(<Uniques as PalletInfoAccess>::index() as u8).into();
 	pub PoolAssetsPalletLocationV3: xcm::v3::Location =
 		xcm::v3::Junction::PalletInstance(<PoolAssets as PalletInfoAccess>::index() as u8).into();
 	pub CheckingAccount: AccountId = PolkadotXcm::check_account();
@@ -145,6 +148,26 @@ pub type FungiblesTransactor = FungiblesAdapter<
 	CheckingAccount,
 >;
 
+/// Matcher for converting `ClassId`/`InstanceId` into a uniques asset.
+pub type UniquesConvertedConcreteId =
+	assets_common::UniquesConvertedConcreteId<UniquesPalletLocation>;
+
+/// Means for transacting unique assets.
+pub type UniquesTransactor = NonFungiblesAdapter<
+	// Use this non-fungibles implementation:
+	Uniques,
+	// This adapter will handle any non-fungible asset from the uniques pallet.
+	UniquesConvertedConcreteId,
+	// Convert an XCM Location into a local account id:
+	LocationToAccountId,
+	// Our chain's account ID type (we can't get away without mentioning it explicitly):
+	AccountId,
+	// Does not check teleports.
+	NoChecking,
+	// The account to use for tracking teleports.
+	CheckingAccount,
+>;
+
 /// `AssetId`/`Balance` converter for `ForeignAssets`.
 pub type ForeignAssetsConvertedConcreteId = assets_common::ForeignAssetsConvertedConcreteId<
 	(
@@ -198,8 +221,13 @@ pub type PoolFungiblesTransactor = FungiblesAdapter<
 >;
 
 /// Means for transacting assets on this chain.
-pub type AssetTransactors =
+pub type AssetTransactors = (
-	(CurrencyTransactor, FungiblesTransactor, ForeignFungiblesTransactor, PoolFungiblesTransactor);
+	CurrencyTransactor,
+	FungiblesTransactor,
+	ForeignFungiblesTransactor,
+	PoolFungiblesTransactor,
+	UniquesTransactor,
+);
 
 /// Simple `Location` matcher for Local and Foreign asset `Location`.
 pub struct LocalAndForeignAssetsLocationMatcher;

cumulus/parachains/runtimes/assets/asset-hub-westend/src/lib.rs

@@ -60,9 +60,9 @@ use parachains_common::{
 	impls::DealWithFees,
 	message_queue::*,
 	westend::{consensus::*, currency::*, fee::WeightToFee},
-	AccountId, AssetIdForTrustBackedAssets, AuraId, Balance, BlockNumber, Hash, Header, Nonce,
+	AccountId, AssetIdForTrustBackedAssets, AuraId, Balance, BlockNumber, CollectionId, Hash,
-	Signature, AVERAGE_ON_INITIALIZE_RATIO, DAYS, HOURS, MAXIMUM_BLOCK_WEIGHT,
+	Header, ItemId, Nonce, Signature, AVERAGE_ON_INITIALIZE_RATIO, DAYS, HOURS,
-	NORMAL_DISPATCH_RATIO, SLOT_DURATION,
+	MAXIMUM_BLOCK_WEIGHT, NORMAL_DISPATCH_RATIO, SLOT_DURATION,
 };
 use sp_api::impl_runtime_apis;
 use sp_core::{crypto::KeyTypeId, OpaqueMetadata};
@@ -748,8 +748,8 @@ parameter_types! {
 
 impl pallet_uniques::Config for Runtime {
 	type RuntimeEvent = RuntimeEvent;
-	type CollectionId = u32;
+	type CollectionId = CollectionId;
-	type ItemId = u32;
+	type ItemId = ItemId;
 	type Currency = Balances;
 	type ForceOrigin = AssetsForceOrigin;
 	type CollectionDeposit = UniquesCollectionDeposit;
@@ -806,8 +806,8 @@ parameter_types! {
 
 impl pallet_nfts::Config for Runtime {
 	type RuntimeEvent = RuntimeEvent;
-	type CollectionId = u32;
+	type CollectionId = CollectionId;
-	type ItemId = u32;
+	type ItemId = ItemId;
 	type Currency = Balances;
 	type CreateOrigin = AsEnsureOriginWithArg<EnsureSigned<AccountId>>;
 	type ForceOrigin = AssetsForceOrigin;

cumulus/parachains/runtimes/assets/asset-hub-westend/src/xcm_config.rs

@@ -17,7 +17,8 @@ use super::{
 	AccountId, AllPalletsWithSystem, Assets, Authorship, Balance, Balances, BaseDeliveryFee,
 	CollatorSelection, FeeAssetId, ForeignAssets, ForeignAssetsInstance, ParachainInfo,
 	ParachainSystem, PolkadotXcm, PoolAssets, Runtime, RuntimeCall, RuntimeEvent, RuntimeOrigin,
-	ToRococoXcmRouter, TransactionByteFee, TrustBackedAssetsInstance, WeightToFee, XcmpQueue,
+	ToRococoXcmRouter, TransactionByteFee, TrustBackedAssetsInstance, Uniques, WeightToFee,
+	XcmpQueue,
 };
 use assets_common::{
 	local_and_foreign_assets::MatchesLocalAndForeignAssetsLocation,
@@ -52,11 +53,12 @@ use xcm_builder::{
 	AllowSubscriptionsFrom, AllowTopLevelPaidExecutionFrom, DenyReserveTransferToRelayChain,
 	DenyThenTry, DescribeFamily, DescribePalletTerminal, EnsureXcmOrigin, FungiblesAdapter,
 	GlobalConsensusParachainConvertsFor, HashedDescription, IsConcrete, LocalMint,
-	NetworkExportTableItem, NoChecking, ParentAsSuperuser, ParentIsPreset, RelayChainAsNative,
+	NetworkExportTableItem, NoChecking, NonFungiblesAdapter, ParentAsSuperuser, ParentIsPreset,
-	SiblingParachainAsNative, SiblingParachainConvertsVia, SignedAccountId32AsNative,
+	RelayChainAsNative, SiblingParachainAsNative, SiblingParachainConvertsVia,
-	SignedToAccountId32, SovereignSignedViaLocation, StartsWith, StartsWithExplicitGlobalConsensus,
+	SignedAccountId32AsNative, SignedToAccountId32, SovereignSignedViaLocation, StartsWith,
-	TakeWeightCredit, TrailingSetTopicAsId, UsingComponents, WeightInfoBounds, WithComputedOrigin,
+	StartsWithExplicitGlobalConsensus, TakeWeightCredit, TrailingSetTopicAsId, UsingComponents,
-	WithUniqueTopic, XcmFeeManagerFromComponents, XcmFeeToAccount,
+	WeightInfoBounds, WithComputedOrigin, WithUniqueTopic, XcmFeeManagerFromComponents,
+	XcmFeeToAccount,
 };
 use xcm_executor::{traits::WithOriginFilter, XcmExecutor};
 
@@ -77,6 +79,8 @@ parameter_types! {
 		PalletInstance(<ForeignAssets as PalletInfoAccess>::index() as u8).into();
 	pub PoolAssetsPalletLocation: Location =
 		PalletInstance(<PoolAssets as PalletInfoAccess>::index() as u8).into();
+	pub UniquesPalletLocation: Location =
+		PalletInstance(<Uniques as PalletInfoAccess>::index() as u8).into();
 	pub PoolAssetsPalletLocationV3: xcm::v3::Location =
 		xcm::v3::Junction::PalletInstance(<PoolAssets as PalletInfoAccess>::index() as u8).into();
 	pub CheckingAccount: AccountId = PolkadotXcm::check_account();
@@ -139,6 +143,26 @@ pub type FungiblesTransactor = FungiblesAdapter<
 	CheckingAccount,
 >;
 
+/// Matcher for converting `ClassId`/`InstanceId` into a uniques asset.
+pub type UniquesConvertedConcreteId =
+	assets_common::UniquesConvertedConcreteId<UniquesPalletLocation>;
+
+/// Means for transacting unique assets.
+pub type UniquesTransactor = NonFungiblesAdapter<
+	// Use this non-fungibles implementation:
+	Uniques,
+	// This adapter will handle any non-fungible asset from the uniques pallet.
+	UniquesConvertedConcreteId,
+	// Convert an XCM Location into a local account id:
+	LocationToAccountId,
+	// Our chain's account ID type (we can't get away without mentioning it explicitly):
+	AccountId,
+	// Does not check teleports.
+	NoChecking,
+	// The account to use for tracking teleports.
+	CheckingAccount,
+>;
+
 /// `AssetId`/`Balance` converter for `ForeignAssets`.
 pub type ForeignAssetsConvertedConcreteId = assets_common::ForeignAssetsConvertedConcreteId<
 	(
@@ -192,8 +216,13 @@ pub type PoolFungiblesTransactor = FungiblesAdapter<
 >;
 
 /// Means for transacting assets on this chain.
-pub type AssetTransactors =
+pub type AssetTransactors = (
-	(CurrencyTransactor, FungiblesTransactor, ForeignFungiblesTransactor, PoolFungiblesTransactor);
+	CurrencyTransactor,
+	FungiblesTransactor,
+	ForeignFungiblesTransactor,
+	PoolFungiblesTransactor,
+	UniquesTransactor,
+);
 
 /// Simple `Location` matcher for Local and Foreign asset `Location`.
 pub struct LocalAndForeignAssetsLocationMatcher;

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

@@ -25,7 +25,7 @@ pub mod runtime_api;
 
 use crate::matching::{LocalLocationPattern, ParentLocation};
 use frame_support::traits::{Equals, EverythingBut};
-use parachains_common::AssetIdForTrustBackedAssets;
+use parachains_common::{AssetIdForTrustBackedAssets, CollectionId, ItemId};
 use xcm_builder::{
 	AsPrefixedGeneralIndex, MatchedConvertedConcreteId, StartsWith, V4V3LocationConverter,
 };
@@ -43,6 +43,10 @@ pub type AssetIdForTrustBackedAssetsConvert<TrustBackedAssetsPalletLocation> =
 pub type AssetIdForTrustBackedAssetsConvertLatest<TrustBackedAssetsPalletLocation> =
 	AsPrefixedGeneralIndex<TrustBackedAssetsPalletLocation, AssetIdForTrustBackedAssets, JustTry>;
 
+/// `Location` vs `CollectionId` converter for `Uniques`
+pub type CollectionIdForUniquesConvert<UniquesPalletLocation> =
+	AsPrefixedGeneralIndex<UniquesPalletLocation, CollectionId, JustTry>;
+
 /// [`MatchedConvertedConcreteId`] converter dedicated for `TrustBackedAssets`
 pub type TrustBackedAssetsConvertedConcreteId<TrustBackedAssetsPalletLocation, Balance> =
 	MatchedConvertedConcreteId<
@@ -53,6 +57,17 @@ pub type TrustBackedAssetsConvertedConcreteId<TrustBackedAssetsPalletLocation, B
 		JustTry,
 	>;
 
+/// [`MatchedConvertedConcreteId`] converter dedicated for `Uniques`
+pub type UniquesConvertedConcreteId<UniquesPalletLocation> = MatchedConvertedConcreteId<
+	CollectionId,
+	ItemId,
+	// The asset starts with the uniques pallet. The `CollectionId` of the asset is specified as a
+	// junction within the pallet itself.
+	StartsWith<UniquesPalletLocation>,
+	CollectionIdForUniquesConvert<UniquesPalletLocation>,
+	JustTry,
+>;
+
 /// [`MatchedConvertedConcreteId`] converter dedicated for storing `AssetId` as `Location`.
 pub type LocationConvertedConcreteId<LocationFilter, Balance> = MatchedConvertedConcreteId<
 	xcm::v3::Location,

prdoc/pr_2796.prdoc

@@ -0,0 +1,12 @@
+title: Rococo and Westend Asset-Hub: XCM Transfers with Pallet-Uniques
+
+doc:
+  - audience: Runtime User
+    description: |
+      With the added `UniquesTransactor` Rococo and Westend Asset-Hub are now capable of handling
+      XCM transfers with pallet-uniques. 
+
+crates:
+  - name: "asset-hub-rococo-runtime"
+  - name: "asset-hub-westend-runtime"
+  - name: "assets-common"