Collect the domain transaction fee and use as the operator reward

domains/pallets/domain-transaction-fees/Cargo.toml

@@ -0,0 +1,32 @@
+[package]
+name = "pallet-domain-transaction-fees"
+version = "0.1.0"
+authors = ["Subspace Labs <https://subspace.network>"]
+edition = "2021"
+license = "Apache-2.0"
+homepage = "https://subspace.network"
+repository = "https://github.com/subspace/subspace"
+description = "Subspace node pallet for charging and re-distributing domain transaction fees"
+include = [
+  "/src",
+  "/Cargo.toml",
+]
+
+[dependencies]
+codec = { package = "parity-scale-codec", version = "3.6.3", default-features = false, features = ["derive"] }
+frame-support = { version = "4.0.0-dev", default-features = false, git = "https://github.com/subspace/substrate", rev = "55c157cff49b638a59d81a9f971f0f9a66829c71" }
+frame-system = { version = "4.0.0-dev", default-features = false, git = "https://github.com/subspace/substrate", rev = "55c157cff49b638a59d81a9f971f0f9a66829c71" }
+scale-info = { version = "2.7.0", default-features = false, features = ["derive"] }
+sp-runtime = { version = "24.0.0", default-features = false, git = "https://github.com/subspace/substrate", rev = "55c157cff49b638a59d81a9f971f0f9a66829c71" }
+sp-std = { version = "8.0.0", default-features = false, git = "https://github.com/subspace/substrate", rev = "55c157cff49b638a59d81a9f971f0f9a66829c71" }
+
+[features]
+default = ["std"]
+std = [
+  "codec/std",
+  "frame-support/std",
+  "frame-system/std",
+  "scale-info/std",
+  "sp-runtime/std",
+  "sp-std/std",
+]

domains/pallets/domain-transaction-fees/src/lib.rs

@@ -0,0 +1,72 @@
+// Copyright (C) 2023 Subspace Labs, Inc.
+// 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.
+
+//! Pallet Domain Transaction Fees
+
+#![cfg_attr(not(feature = "std"), no_std)]
+
+pub use pallet::*;
+
+#[frame_support::pallet]
+mod pallet {
+    use codec::{Codec, MaxEncodedLen};
+    use frame_support::pallet_prelude::*;
+    use frame_system::pallet_prelude::*;
+    use scale_info::TypeInfo;
+    use sp_runtime::traits::{AtLeast32BitUnsigned, MaybeSerializeDeserialize, Saturating, Zero};
+    use sp_runtime::FixedPointOperand;
+    use sp_std::fmt::Debug;
+
+    #[pallet::config]
+    pub trait Config: frame_system::Config {
+        /// The balance of an account.
+        type Balance: Parameter
+            + Member
+            + AtLeast32BitUnsigned
+            + Codec
+            + Default
+            + Copy
+            + MaybeSerializeDeserialize
+            + Debug
+            + MaxEncodedLen
+            + TypeInfo
+            + FixedPointOperand;
+    }
+
+    // The accumulated transaction fee of all transactions included in current block
+    #[pallet::storage]
+    #[pallet::getter(fn block_transaction_fee)]
+    pub(super) type BlockTransactionFee<T: Config> = StorageValue<_, T::Balance, ValueQuery>;
+
+    /// Pallet domain-transaction-fees to store the domain block transaction fee.
+    #[pallet::pallet]
+    #[pallet::without_storage_info]
+    pub struct Pallet<T>(_);
+
+    #[pallet::hooks]
+    impl<T: Config> Hooks<BlockNumberFor<T>> for Pallet<T> {
+        fn on_initialize(_now: BlockNumberFor<T>) -> Weight {
+            BlockTransactionFee::<T>::set(Zero::zero());
+            T::DbWeight::get().writes(1)
+        }
+    }
+
+    impl<T: Config> Pallet<T> {
+        pub fn note_transaction_fees(tx_fee: T::Balance) {
+            let next_tx_fee = BlockTransactionFee::<T>::get().saturating_add(tx_fee);
+            BlockTransactionFee::<T>::set(next_tx_fee);
+        }
+    }
+}