Overview The RelayFacet enables cross-chain token transfers using the Relay Protocol. Relay provides fast and secure cross-chain transfers with support for non-EVM chains.
Contract Interface State Functions relayReceiver Returns the address of the Relay receiver contract.
function relayReceiver () external view returns ( address )
relaySolver Returns the address of the Relay solver.
function relaySolver () external view returns ( address )
consumedIds Checks if a request ID has been consumed.
function consumedIds ( bytes32 requestId ) external view returns ( bool )
Bridging Functions startBridgeTokensViaRelay Bridges tokens to another chain using Relay Protocol.
function startBridgeTokensViaRelay ( BridgeData _bridgeData , RelayData _relayData ) external payable
Standard bridge data containing transaction details
Relay-specific bridging parameters Unique request identifier
Receiver address on non-EVM chains
Asset to receive on destination
Relay signature for verification
swapAndStartBridgeTokensViaRelay Performs a token swap on the source chain before bridging via Relay.
function swapAndStartBridgeTokensViaRelay ( BridgeData _bridgeData , SwapData [] _swapData , RelayData _relayData ) external payable
Array of swap operations to execute before bridging
Relay-specific parameters
Data Structures RelayData struct RelayData { bytes32 requestId ; // Request ID bytes32 nonEVMReceiver ; // Non-EVM receiver bytes32 receivingAssetId ; // Receiving asset ID bytes signature ; // Relay signature }
Usage Example import { RelayFacet } from '@lifi/contract-types' ; const relayFacet = RelayFacet__factory . connect ( facetAddress , signer ); const bridgeData = { transactionId: '0x...' , bridge: 'relay' , integrator: 'my-dapp' , referrer: '0x0000000000000000000000000000000000000000' , sendingAssetId: '0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48' , // USDC receiver: '0x...' , minAmount: ethers . utils . parseUnits ( '100' , 6 ), destinationChainId: 8453 , // Base hasSourceSwaps: false , hasDestinationCall: false }; const relayData = { requestId: ethers . utils . randomBytes ( 32 ), nonEVMReceiver: '0x0000000000000000000000000000000000000000000000000000000000000000' , receivingAssetId: '0x0000000000000000000000000000000000000000000000000000000000000000' , signature: '0x...' }; const tx = await relayFacet . startBridgeTokensViaRelay ( bridgeData , relayData , { value: 0 } ); await tx . wait ();
Events The facet emits standard LiFi events:
LiFiTransferStarted(BridgeData bridgeData)LiFiTransferCompletedAssetSwapped (when using swapAndStart variant)BridgeToNonEVMChain (for non-EVM destinations)BridgeToNonEVMChainBytes32 (for non-EVM destinations with bytes32 receiver)
See Also