Support paying DOT as a fee (#404)

* generic template implemented

* support pay do as a fee

* update locks with latest fixes

* docs & tests

* fix clippy

* fix fmt

evm-template/runtime/src/configs/mod.rs

@@ -18,8 +18,8 @@ use frame_support::{
     dispatch::DispatchClass,
     parameter_types,
     traits::{
-        AsEnsureOriginWithArg, ConstU128, ConstU16, ConstU32, ConstU64, Contains, EitherOf,
-        EitherOfDiverse, Everything, FindAuthor, Nothing, TransformOrigin,
+        fungibles::Credit, AsEnsureOriginWithArg, ConstU128, ConstU16, ConstU32, ConstU64,
+        Contains, EitherOf, EitherOfDiverse, Everything, FindAuthor, Nothing, TransformOrigin,
     },
     weights::{ConstantMultiplier, Weight},
 };
@@ -43,9 +43,13 @@ use openzeppelin_pallet_abstractions::{
 };
 #[cfg(feature = "tanssi")]
 use openzeppelin_pallet_abstractions::{impl_openzeppelin_tanssi, TanssiConfig, TanssiWeight};
+use pallet_asset_tx_payment::HandleCredit;
 use pallet_ethereum::PostLogContent;
 use pallet_evm::{EVMCurrencyAdapter, EnsureAccountId20, IdentityAddressMapping};
-use parachains_common::message_queue::{NarrowOriginToSibling, ParaIdToSibling};
+use parachains_common::{
+    impls::AccountIdOf,
+    message_queue::{NarrowOriginToSibling, ParaIdToSibling},
+};
 use parity_scale_codec::{Decode, Encode};
 use polkadot_runtime_common::{BlockHashCount, SlowAdjustingFeeUpdate};
 #[cfg(not(feature = "tanssi"))]
@@ -93,10 +97,10 @@ use crate::{
     },
     weights::{BlockExecutionWeight, ExtrinsicBaseWeight},
     AllPalletsWithSystem, AssetManager, Balances, BaseFee, EVMChainId, Erc20XcmBridge,
-    MessageQueue, OpenZeppelinPrecompiles, OriginCaller, PalletInfo, ParachainInfo,
-    ParachainSystem, PolkadotXcm, Preimage, Referenda, Runtime, RuntimeCall, RuntimeEvent,
-    RuntimeFreezeReason, RuntimeHoldReason, RuntimeOrigin, RuntimeTask, Scheduler, System,
-    Timestamp, Treasury, UncheckedExtrinsic, WeightToFee, XcmpQueue,
+    MessageQueue, OpenZeppelinPrecompiles, Oracle, OracleMembership, OriginCaller, PalletInfo,
+    ParachainInfo, ParachainSystem, PolkadotXcm, Preimage, Referenda, Runtime, RuntimeCall,
+    RuntimeEvent, RuntimeFreezeReason, RuntimeHoldReason, RuntimeOrigin, RuntimeTask, Scheduler,
+    System, Timestamp, Treasury, UncheckedExtrinsic, WeightToFee, XcmpQueue,
 };
 
 // OpenZeppelin runtime wrappers configuration
@@ -198,7 +202,28 @@ impl EvmConfig for OpenZeppelinRuntime {
     type PrecompilesValue = PrecompilesValue;
     type WithdrawOrigin = EnsureAccountId20;
 }
+
+parameter_types! {
+    pub RootOperatorAccountId: AccountId = AccountId::from([0xffu8; 20]);
+}
+
+pub struct AssetsToBlockAuthor<R, I>(PhantomData<(R, I)>);
+impl<R, I> HandleCredit<AccountIdOf<R>, pallet_assets::Pallet<R, I>> for AssetsToBlockAuthor<R, I>
+where
+    I: 'static,
+    R: pallet_authorship::Config + pallet_assets::Config<I>,
+{
+    fn handle_credit(credit: Credit<AccountIdOf<R>, pallet_assets::Pallet<R, I>>) {
+        use frame_support::traits::fungibles::Balanced;
+        if let Some(author) = pallet_authorship::Pallet::<R>::author() {
+            // In case of error: Will drop the result triggering the `OnDrop` of the imbalance.
+            let _ = pallet_assets::Pallet::<R, I>::resolve(&author, credit);
+        }
+    }
+}
+
 impl AssetsConfig for OpenZeppelinRuntime {
+    type AccountId = AccountId;
     type ApprovalDeposit = ConstU128<MILLICENTS>;
     type AssetAccountDeposit = ConstU128<{ deposit(1, 16) }>;
     type AssetDeposit = ConstU128<{ 10 * CENTS }>;
@@ -206,11 +231,15 @@ impl AssetsConfig for OpenZeppelinRuntime {
     type AssetRegistrar = AssetRegistrar;
     type AssetRegistrarMetadata = AssetRegistrarMetadata;
     type AssetType = AssetType;
+    type AssetsToBlockAuthor = AssetsToBlockAuthor<Runtime, ()>;
     #[cfg(feature = "runtime-benchmarks")]
     type BenchmarkHelper = BenchmarkHelper;
     type CreateOrigin = AsEnsureOriginWithArg<EnsureSigned<AccountId>>;
     type ForceOrigin = EnsureRoot<AccountId>;
     type ForeignAssetModifierOrigin = EnsureRoot<AccountId>;
+    type FungiblesToAccount = TreasuryAccount;
+    type RootOperatorAccountId = RootOperatorAccountId;
+    type Timestamp = Timestamp;
     type WeightToFee = WeightToFee;
 }
 #[cfg(feature = "tanssi")]
@@ -283,6 +312,77 @@ impl fp_rpc::ConvertTransaction<opaque::UncheckedExtrinsic> for TransactionConve
 
 #[cfg(test)]
 mod tests {
+    mod assets_to_block_author {
+        use frame_support::traits::fungibles::Balanced;
+        use pallet_asset_tx_payment::HandleCredit;
+        use parity_scale_codec::Encode;
+        use sp_runtime::{
+            testing::{Digest, DigestItem},
+            ConsensusEngineId,
+        };
+
+        use crate::{
+            configs::AssetsToBlockAuthor, AccountId, Assets, Balance, Runtime, RuntimeOrigin,
+        };
+
+        pub const MOCK_ENGINE_ID: ConsensusEngineId = [b'M', b'O', b'C', b'K'];
+        #[test]
+        fn handle_credit_works_when_author_exists() {
+            new_test_ext().execute_with(|| {
+                // Setup
+                let data = [0u8; 32];
+                let author: AccountId = AccountId::from(data);
+                const ASSET_ID: u128 = 1;
+                const AMOUNT: Balance = 100;
+
+                let mut digest = Digest::default();
+                digest.push(DigestItem::PreRuntime(MOCK_ENGINE_ID, author.encode()));
+                // For unit tests we are updating storage of author in a straightforward way
+                frame_support::storage::unhashed::put(
+                    &frame_support::storage::storage_prefix(b"Authorship", b"Author"),
+                    &author,
+                );
+                // Create asset and mint initial supply
+                assert!(Assets::force_create(
+                    RuntimeOrigin::root(),
+                    ASSET_ID.into(),
+                    author,
+                    true,
+                    1
+                )
+                .is_ok());
+
+                // Create credit using issue
+                let credit = Assets::issue(ASSET_ID, AMOUNT);
+
+                // Handle credit
+                AssetsToBlockAuthor::<Runtime, ()>::handle_credit(credit);
+
+                // Verify author received the assets
+                assert_eq!(Assets::balance(ASSET_ID, author), AMOUNT);
+            });
+        }
+
+        #[test]
+        fn handle_credit_drops_when_no_author() {
+            new_test_ext().execute_with(|| {
+                // Setup
+                const ASSET_ID: u128 = 1;
+                const AMOUNT: Balance = 100;
+
+                // Create credit using issue
+                let credit = Assets::issue(ASSET_ID, AMOUNT);
+
+                // Handle credit (should not panic)
+                AssetsToBlockAuthor::<Runtime, ()>::handle_credit(credit);
+            });
+        }
+
+        fn new_test_ext() -> sp_io::TestExternalities {
+            use sp_runtime::BuildStorage;
+            frame_system::GenesisConfig::<Runtime>::default().build_storage().unwrap().into()
+        }
+    }
     mod transaction_converter {
         use core::str::FromStr;
 

evm-template/runtime/src/configs/weight.rs

@@ -33,6 +33,9 @@ impl ConsensusWeight for OpenZeppelinRuntime {
 impl AssetsWeight for OpenZeppelinRuntime {
     type AssetManager = weights::pallet_asset_manager::WeightInfo<Runtime>;
     type Assets = weights::pallet_assets::WeightInfo<Runtime>;
+    // TODO: fix weight
+    type OracleMembership = ();
+    type OrmlOracle = (); // TODO: fix weight
 }
 
 impl GovernanceWeight for OpenZeppelinRuntime {

evm-template/runtime/src/lib.rs

@@ -40,7 +40,8 @@ use crate::{
 pub use crate::{
     configs::RuntimeBlockWeights,
     types::{
-        AccountId, Balance, Block, BlockNumber, Executive, Nonce, Signature, UncheckedExtrinsic,
+        AccountId, AssetId, Balance, Block, BlockNumber, Executive, Nonce, Signature,
+        UncheckedExtrinsic,
     },
 };
 #[cfg(feature = "runtime-benchmarks")]
@@ -50,7 +51,7 @@ use crate::{
         XcmExecutorConfig,
     },
     constants::currency::{CENTS, EXISTENTIAL_DEPOSIT},
-    types::{Address, AssetId},
+    types::Address,
 };
 #[cfg(feature = "async-backing")]
 use crate::{constants::SLOT_DURATION, types::ConsensusHook};
@@ -240,6 +241,8 @@ mod apis {
         type RuntimeCall = RuntimeCall;
         type TransactionPayment = TransactionPayment;
         type Balance = Balance;
+        type Oracle = Oracle;
+        type OracleKey = AssetId;
     }
 
     mod consensus {
@@ -294,6 +297,8 @@ mod apis {
         type RuntimeCall = RuntimeCall;
         type Executive = Executive;
         type Ethereum = Ethereum;
+        type Oracle = Oracle;
+        type OracleKey = AssetId;
     }
 
     mod assets {

evm-template/runtime/src/types.rs

@@ -83,7 +83,7 @@ pub type SignedExtra = (
     frame_system::CheckEra<Runtime>,
     frame_system::CheckNonce<Runtime>,
     frame_system::CheckWeight<Runtime>,
-    pallet_transaction_payment::ChargeTransactionPayment<Runtime>,
+    pallet_asset_tx_payment::ChargeAssetTxPayment<Runtime>,
     frame_metadata_hash_extension::CheckMetadataHash<Runtime>,
     cumulus_primitives_storage_weight_reclaim::StorageWeightReclaim<Runtime>,
 );