Arb Executor Notes

Fee Structure

Fee reserves are logged per execution in results/xcmReserveFees example as ReserveFeeData

arb-finder uses feeBook to calculate xcm fees feeBook

Arb-Finder types

arb-finder rust structs that parse [feeBook] pub struct TransferDepositFeeBook{ #[serde(rename = "polkadot-transfer")] pub polkadot_transfer: HashMap<String, ChainTransferData>, #[serde(rename = "polkadot-deposit")] pub polkadot_deposit: HashMap<String, ChainDepositData>, } pub struct ChainTransferData { #[serde(flatten)] pub assets: HashMap<String, TransferData>, } pub struct ChainDepositData { #[serde(flatten)] pub assets: HashMap<String, DepositData>, } pub struct TransferData { pub transferAmount: Option, pub transferDecimals: Option, pub transferAssetSymbol: Option, // #[serde(deserialize_with = "deserialize_to_string")] transferAssetId: serde_json::Value, pub feeAmount: Option, pub feeDecimals: Option, pub feeAssetSymbol: Option, // #[serde(deserialize_with = "deserialize_to_string")] feeAssetId: serde_json::Value, } pub struct DepositData { pub depositAmount: Option, pub feeAmount: Option, pub feeDecimals: Option, pub feeAssetSymbol: Option, // #[serde(deserialize_with = "deserialize_to_string")] feeAssetId: serde_json::Value, }

Arb-Executor Fee Types

export interface DepositEventData { depositAmount: bn depositAssetSymbol: string, depositAssetId: string, depositAssetDecimals: number, feeAmount: bn, feeAssetSymbol: string, feeAssetId: string, feeAssetDecimals: number, node: PNode }

export interface TransferEventData { transferAmount: bn, transferAssetSymbol: string, transferAssetId: string, transferAssetDecimals: number, feeAmount: bn, feeAssetSymbol: string, feeAssetId: string, feeAssetDecimals: number, node: PNode }

export interface ReserveFeeData { chainId: number, feeAssetId: string, feeAssetAmount: string, reserveAssetId: string, reserveAssetAmount: string }

Execution Flow

Fees are logged at the end of each successful xcm transfer

executeSingleTransferExtrinsic

• logEventFeeBook - (TransferEventData and DepositEventData from transfer event listeners. FeeBook used by arb finder)
• updateAccumulatedFeeData - Updates globalState.accumulatedFees (used in logAccumulatedFees()), accumulatedFees.json file (test file), feeTracker.json/chopsticksFeeTracker.json
• updateXcmFeeReserves - Adds ReserveFeeData from latest transfer to globalState.xcmFeeReserves