nexus-sdk-bridge-flows（nexus SDK bridge flows 命令行）

Bridge and Execute Flows

Call bridge(params, options?)

• Use to move tokens cross-chain (intent-based bridge).
• Signature:

- sdk.bridge(params, {onEvent?})

• Params (BridgeParams):

- token: string — token symbol (e.g., "ETH", "USDC") - amount: bigint — smallest units - toChainId: number — destination chain id - recipient?: Hex — defaults to connected user address - gas?: bigint — optional native gas to deliver on destination - sourceChains?: number[] — restrict source chains

• Result (BridgeResult):

- explorerUrl: string - sourceTxs: {chain, hash, explorerUrl}[] - intent: ReadableIntent

Call bridgeAndTransfer(params, options?)

• Use to bridge and transfer to a recipient address.
• Signature:

- sdk.bridgeAndTransfer(params, {onEvent?})

• Params (TransferParams):

- token: string - amount: bigint - toChainId: number - recipient: Hex - sourceChains?: number[]

• Result (TransferResult):

- transactionHash: string - explorerUrl: string

Call bridgeAndExecute(params, options?)

• Use to bridge (if needed) and then execute a contract call.
• Signature:

- sdk.bridgeAndExecute(params, {onEvent?, beforeExecute?})

• Params (BridgeAndExecuteParams):

- token: string, amount: bigint, toChainId: number - execute: Omit<ExecuteParams, "toChainId"> - Optional: waitForReceipt, requiredConfirmations, timeouts

• beforeExecute hook (optional):

- beforeExecute?: () => Promise<{value?: bigint; data?: Hex; gas?: bigint}> - Use to dynamically override execute payload before sending.

• Result (BridgeAndExecuteResult):

- executeTransactionHash: string - executeExplorerUrl: string - bridgeExplorerUrl?: string (undefined if bridge skipped) - bridgeSkipped: boolean - intent?: ReadableIntent

Call execute(params, options?)

• Use for a standalone contract call on a chain.
• Signature:

- sdk.execute(params, {onEvent?})

• Params (ExecuteParams):

- toChainId: number - to: Hex (contract address) - data?: Hex - value?: bigint - gas?: bigint (optional but recommended for deterministic behavior) - gasPrice?: 'low' | 'medium' | 'high' - Optional receipt config: waitForReceipt, receiptTimeout, requiredConfirmations - Optional tokenApproval?: {token: string; amount: bigint; spender: Hex}

• Result (ExecuteResult):

- transactionHash, explorerUrl, chainId - optional receipt fields

Use simulation helpers

• Call sdk.simulateBridge(params) → SimulationResult.
• Call sdk.simulateBridgeAndTransfer(params) → BridgeAndExecuteSimulationResult.
• Call sdk.simulateBridgeAndExecute(params) → BridgeAndExecuteSimulationResult.
• Use simulation to show fees and gas before execution.
• Expect BridgeAndExecuteSimulationResult.bridgeSimulation to be null if bridge is skipped.

Compute max bridgeable amount

• Call sdk.calculateMaxForBridge({token, toChainId, recipient?, sourceChains?}).
• Use BridgeMaxResult to set “max” or validate input.

Convert amounts to bigint

• Use sdk.convertTokenReadableAmountToBigInt(amountString, tokenSymbol, chainId).
• Or use sdk.utils.parseUnits(value, decimals) if decimals are known.

Attach hooks and events

• Attach intent and allowance hooks before calling bridge flows.
• Use NEXUS_EVENTS.STEPS_LIST and NEXUS_EVENTS.STEP_COMPLETE for progress UI.

Handle common failures

• On throw, clear intent/allowance refs and reset UI state.
• On user cancel, call deny() on the active hook and abort.