Execute a Swap

Use the response from the previous step to perform a swap

As outlined in the previous page, the /routes endpoint will return data with the shape of:

interface ReturnData {
    expectedOut: string,
    routerAddress: Address,
    details: {
        path: Address[],
        pairs: Address[],
        extras: string[],
        inputAmount: BigNumberString,
        expectedOutputAmount: BigNumberString,
        deadline: number,
        partner: number,
        sig: string
    }
}

type Address = string
type BigNumberString = string 

For executing a swap, every field that is needed is contained within the details object.

Here is a breakdown of the details object:

Field	Type	Description
path	Array of strings	An array containing token addresses in order of the swap route. The final item in the path should be the outputToken that was supplied in the previous query.
pairs	Array of strings	An array containing addresses of trade pairs, in order of the swap route.
extras	Array of strings	Extra data needed for each pair.
inputAmount	string	Non decimal-adjusted input amount. Same value as supplied to the endpoint.
expectedOutputAmount	string	Non decimal-adjusted expected output amount. This value should be used, along with some slippage value, to determine the minimum expected output.
deadline	integer	Unix timestamp (seconds) of when the trade must be executed by.
partner	integer	The tenant id for the corresponding api key supplied in the request from Query a Swap
sig	string	Signed message verifying the tenant id along with various other aspects of the trade. If this is modified at all then the user will incur a 1% fee due to the contract not being able to verify the authorizer of the swap.

The details purposefully details the struct recognized by the Swap router as SwapPayload. This struct looks like:

struct SwapPayload {
		address[] path;
		address[] pairs;
		bytes[] extras;
		uint256 inputAmount;
		uint256 minOutputAmount;
		uint256 expectedOutputAmount;
		address to;
		uint deadline;
		uint256 partner;
		bytes sig;
	}

Using the above details, the transaction can be created for the Swap router. The address for the swap router is supplied in the response from GET /routes. The function to call has the following declaration:

function swapExactInputForOutput(
		SwapPayload calldata details
	) external returns (uint256 outputAmount);

Once the transaction has been created, use the user's preferred wallet provider to sign the transaction and send it to be committed on chain.