Transaction Fee Module

Cargo.toml

@@ -64,6 +64,7 @@ members = [
 	"srml/democracy",
 	"srml/example",
 	"srml/executive",
+	"srml/fees",
 	"srml/grandpa",
 	"srml/indices",
 	"srml/metadata",

core/sr-primitives/src/traits.rs

@@ -126,15 +126,57 @@ pub trait BlockNumberToHash {
 	}
 }
 
-/// Simple payment making trait, operating on a single generic `AccountId` type.
-pub trait MakePayment<AccountId> {
-	/// Make some sort of payment concerning `who` for an extrinsic (transaction) of encoded length
-	/// `encoded_len` bytes. Return true iff the payment was successful.
-	fn make_payment(who: &AccountId, encoded_len: usize) -> Result<(), &'static str>;
+/// Charge bytes fee trait
+pub trait ChargeBytesFee<AccountId> {
+	/// Charge fees from `transactor` for an extrinsic (transaction) of encoded length
+	/// `encoded_len` bytes. Return Ok iff the payment was successful.
+	fn charge_base_bytes_fee(transactor: &AccountId, encoded_len: usize) -> Result<(), &'static str>;
 }
 
-impl<T> MakePayment<T> for () {
-	fn make_payment(_: &T, _: usize) -> Result<(), &'static str> { Ok(()) }
+/// Charge fee trait
+pub trait ChargeFee<AccountId>: ChargeBytesFee<AccountId> {
+	/// The type of fee amount.
+	type Amount;
+
+	/// Charge `amount` of fees from `transactor`. Return Ok iff the payment was successful.
+	fn charge_fee(transactor: &AccountId, amount: Self::Amount) -> Result<(), &'static str>;
+
+	/// Refund `amount` of previous charged fees from `transactor`. Return Ok iff the refund was successful.
+	fn refund_fee(transactor: &AccountId, amount: Self::Amount) -> Result<(), &'static str>;
+}
+
+/// Transfer fungible asset trait
+pub trait TransferAsset<AccountId> {
+	/// The type of asset amount.
+	type Amount;
+
+	/// Transfer asset from `from` account to `to` account with `amount` of asset.
+	fn transfer(from: &AccountId, to: &AccountId, amount: Self::Amount) -> Result<(), &'static str>;
+
+	/// Remove asset from `who` account by deducing `amount` in the account balances.
+	fn remove_from(who: &AccountId, amount: Self::Amount) -> Result<(), &'static str>;
+
+	/// Add asset to `who` account by increasing `amount` in the account balances.
+	fn add_to(who: &AccountId, amount: Self::Amount) -> Result<(), &'static str>;
+}
+
+impl<T> ChargeBytesFee<T> for () {
+	fn charge_base_bytes_fee(_: &T, _: usize) -> Result<(), &'static str> { Ok(()) }
+}
+
+impl<T> ChargeFee<T> for () {
+	type Amount = ();
+
+	fn charge_fee(_: &T, _: Self::Amount) -> Result<(), &'static str> { Ok(()) }
+	fn refund_fee(_: &T, _: Self::Amount) -> Result<(), &'static str> { Ok(()) }
+}
+
+impl<T> TransferAsset<T> for () {
+	type Amount = ();
+
+	fn transfer(_: &T, _: &T, _: Self::Amount) -> Result<(), &'static str> { Ok(()) }
+	fn remove_from(_: &T, _: Self::Amount) -> Result<(), &'static str> { Ok(()) }
+	fn add_to(_: &T, _: Self::Amount) -> Result<(), &'static str> { Ok(()) }
 }
 
 /// Extensible conversion trait. Generic over both source and destination types.

node-template/runtime/Cargo.toml

@@ -16,13 +16,15 @@ version = { package = "sr-version", path = "../../core/sr-version", default_feat
 srml-support = { path = "../../srml/support", default_features = false }
 primitives = { package = "substrate-primitives", path = "../../core/primitives", default_features = false }
 balances = { package = "srml-balances", path = "../../srml/balances", default_features = false }
+fees = { package = "srml-fees", path = "../../srml/fees", default_features = false }
 consensus = { package = "srml-consensus", path = "../../srml/consensus", default_features = false }
 aura = { package = "srml-aura", path = "../../srml/aura", default_features = false }
 executive = { package = "srml-executive", path = "../../srml/executive", default_features = false }
 indices = { package = "srml-indices", path = "../../srml/indices", default_features = false }
 system = { package = "srml-system", path = "../../srml/system", default_features = false }
 timestamp = { package = "srml-timestamp", path = "../../srml/timestamp", default_features = false }
 sudo = { package = "srml-sudo", path = "../../srml/sudo", default_features = false }
+fees = { package = "srml-fees", path = "../../srml/fees", default_features = false }
 runtime-primitives = { package = "sr-primitives", path = "../../core/sr-primitives", default_features = false }
 substrate-client = { path = "../../core/client", default_features = false }
 consensus-aura = { package = "substrate-consensus-aura-primitives", path = "../../core/consensus/aura/primitives", default_features = false }
@@ -38,13 +40,15 @@ std = [
 	"runtime-io/std",
 	"srml-support/std",
 	"balances/std",
+	"fees/std",
 	"executive/std",
 	"aura/std",
 	"indices/std",
 	"primitives/std",
 	"system/std",
 	"timestamp/std",
 	"sudo/std",
+	"fees/std",
 	"version/std",
 	"serde_derive",
 	"serde/std",

node-template/runtime/src/lib.rs

@@ -167,12 +167,24 @@ impl balances::Trait for Runtime {
 	type Event = Event;
 }
 
+impl fees::Trait for Runtime {
+	type Amount = u128;
+	type TransferAsset = Balances;
+	type Event = Event;
+}
+
 impl sudo::Trait for Runtime {
 	/// The uniquitous event type.
 	type Event = Event;
 	type Proposal = Call;
 }
 
+impl fees::Trait for Runtime {
+	type Event = Event;
+	type Amount = u128;
+	type TransferAsset = balances::Module<Runtime>;
+}
+
 construct_runtime!(
 	pub enum Runtime with Log(InternalLog: DigestItem<Hash, Ed25519AuthorityId>) where
 		Block = Block,
@@ -186,6 +198,7 @@ construct_runtime!(
 		Indices: indices,
 		Balances: balances,
 		Sudo: sudo,
+		Fees: fees::{Module, Storage, Config<T>, Event<T>},
 	}
 );
 
@@ -204,7 +217,7 @@ pub type UncheckedExtrinsic = generic::UncheckedMortalCompactExtrinsic<Address,
 /// Extrinsic type that has already been checked.
 pub type CheckedExtrinsic = generic::CheckedExtrinsic<AccountId, Nonce, Call>;
 /// Executive: handles dispatch to the various modules.
-pub type Executive = executive::Executive<Runtime, Block, Context, Balances, AllModules>;
+pub type Executive = executive::Executive<Runtime, Block, Context, Fees, AllModules>;
 
 // Implement our runtime API endpoints. This is just a bunch of proxying.
 impl_runtime_apis! {

node-template/src/chain_spec.rs

@@ -1,7 +1,7 @@
 use primitives::{Ed25519AuthorityId, ed25519};
 use node_template_runtime::{
 	AccountId, GenesisConfig, ConsensusConfig, TimestampConfig, BalancesConfig,
-	SudoConfig, IndicesConfig
+	SudoConfig, IndicesConfig, FeesConfig,
 };
 use substrate_service;
 
@@ -90,8 +90,6 @@ fn testnet_genesis(initial_authorities: Vec<Ed25519AuthorityId>, endowed_account
 			ids: endowed_accounts.clone(),
 		}),
 		balances: Some(BalancesConfig {
-			transaction_base_fee: 1,
-			transaction_byte_fee: 0,
 			existential_deposit: 500,
 			transfer_fee: 0,
 			creation_fee: 0,
@@ -101,5 +99,9 @@ fn testnet_genesis(initial_authorities: Vec<Ed25519AuthorityId>, endowed_account
 		sudo: Some(SudoConfig {
 			key: root_key,
 		}),
+		fees: Some(FeesConfig {
+			transaction_base_fee: 1,
+			transaction_byte_fee: 0,
+		})
 	}
 }

node/cli/src/chain_spec.rs

@@ -20,7 +20,7 @@ use primitives::{Ed25519AuthorityId, ed25519};
 use node_primitives::AccountId;
 use node_runtime::{ConsensusConfig, CouncilSeatsConfig, CouncilVotingConfig, DemocracyConfig,
 	SessionConfig, StakingConfig, TimestampConfig, BalancesConfig, TreasuryConfig,
-	SudoConfig, ContractConfig, GrandpaConfig, IndicesConfig, Permill, Perbill};
+	SudoConfig, ContractConfig, GrandpaConfig, IndicesConfig, FeesConfig, Permill, Perbill};
 pub use node_runtime::GenesisConfig;
 use substrate_service;
 use hex_literal::{hex, hex_impl};
@@ -64,8 +64,6 @@ fn staging_testnet_config_genesis() -> GenesisConfig {
 		system: None,
 		balances: Some(BalancesConfig {
 			balances: endowed_accounts.iter().map(|&k| (k, 10_000_000 * DOLLARS)).collect(),
-			transaction_base_fee: 1 * CENTS,
-			transaction_byte_fee: 10 * MILLICENTS,
 			existential_deposit: 1 * DOLLARS,
 			transfer_fee: 1 * CENTS,
 			creation_fee: 1 * CENTS,
@@ -139,7 +137,11 @@ fn staging_testnet_config_genesis() -> GenesisConfig {
 		}),
 		grandpa: Some(GrandpaConfig {
 			authorities: initial_authorities.clone().into_iter().map(|k| (k, 1)).collect(),
-		})
+		}),
+		fees: Some(FeesConfig {
+			transaction_base_fee: 1 * CENTS,
+			transaction_byte_fee: 10 * MILLICENTS,
+		}),
 	}
 }
 
@@ -192,8 +194,6 @@ pub fn testnet_genesis(
 			ids: endowed_accounts.iter().map(|x| x.0.into()).collect(),
 		}),
 		balances: Some(BalancesConfig {
-			transaction_base_fee: 1,
-			transaction_byte_fee: 0,
 			existential_deposit: 500,
 			transfer_fee: 0,
 			creation_fee: 0,
@@ -267,7 +267,11 @@ pub fn testnet_genesis(
 		}),
 		grandpa: Some(GrandpaConfig {
 			authorities: initial_authorities.clone().into_iter().map(|k| (k, 1)).collect(),
-		})
+		}),
+		fees: Some(FeesConfig {
+			transaction_base_fee: 1,
+			transaction_byte_fee: 0,
+		}),
 	}
 }
 

node/executor/Cargo.toml

@@ -31,6 +31,7 @@ treasury = { package = "srml-treasury", path = "../../srml/treasury" }
 contract = { package = "srml-contract", path = "../../srml/contract" }
 grandpa = { package = "srml-grandpa", path = "../../srml/grandpa" }
 indices = { package = "srml-indices", path = "../../srml/indices" }
+fees = { package = "srml-fees", path = "../../srml/fees" }
 wabt = "~0.7.4"
 
 [features]