4️⃣Execute a Route (Transfer)

We allow you to execute any on-chain or cross-chain swap and bridging process and a combination of both.

After fetching routes, you can execute one using executeRoute as described here.

async function executeRoute (
  signer: Signer,
  route: Route,
  settings?: ExecutionSettings
): Promise<Route>
  
interface ExecutionSettings {
  acceptExchangeRateUpdateHook?: AcceptExchangeRateUpdateHook
  switchChainHook?: SwitchChainHook
  updateRouteHook?: UpdateRouteHook
  updateTransactionRequestHook?: TransactionRequestUpdateHook
  executeInBackground?: boolean
  infiniteApproval?: boolean
}

Executing a route requires a signer to send transactions to involved contracts. You can read more about signers in the official ethers documentation. Once you have the route and the signer, you call executeRoute.

const route = await lifi.executeRoute(signer, route)

Note that the function will return the executed route once the execution has been completed.

In addition to the first two parameters, executeRoute takes an optional settings object as a third parameter.

switchChainHook

pageHandling Chain Switches

updateRouteHook

This function will be called every time the SDK performs an action on the route. You can use this callback to keep track of the execution status.

acceptExchangeRateUpdateHook

This function will be called every time the rate changes during swap/bridge and will provide old and new amount values to you. You should return true as a result to continue the execution. When you don't provide this hook or return false - SDK throws an error (TransactionError: Exchange rate has changed!).

updateTransactionRequestHook

This hook is intended for advanced usage and you can use it to modify transaction or token approval requests e.g. updating gas price.

Controlling the execution of a route

moveExecutionToBackground

function moveExecutionToBackground(route: Route): void

Once a route execution has started, it can be pushed "to the background" by calling this method. Once called, the execution will continue until it reaches a point where user interaction is required (i.e. signing a transaction). If such a point is reached, the execution will halt until resumeRoute is called with the same route object. The execution will then pick up where it halted.

stopExecution

function stopExecution(route: Route): Route

This method immediately stops the execution of a given route. If a transaction has already been signed and sent by the user, it will be executed on-chain.

updateExecutionSettings

function updateExecutionSettings (
    settings: ExecutionSettings,
    route: Route
  ): void 

This function updates the execution settings of a route. Please see #executeroute for the ExecutionSettings interface.

resumeRoute

async function resumeRoute (
    signer: Signer,
    route: Route,
    settings?: ExecutionSettings
  ): Promise<Route>

resumeRoute takes in the same parameters as executeRoute and will resume either a route that has been stopped or a route that has been moved to the background.

Example code snippet

Building on the code from Request a Route we can now choose a route and execute it.

// getting routes
const routeOptions = { ... }
const routesRequest = { ... }

const result = await lifi.getRoutes(routesRequest)
const routes = result.routes
const chosenRoute = routes[0]

const updateCallback = (updatedRoute: Route) => {
    console.log('Ping! Everytime a status update is made!')
}

// executing a route
const route = await lifi.executeRoute(signer, chosenRoute, { updateCallback })