# Solidity API ## RelayPool ERC4626 vault that enables cross-chain asset bridging and yield generation. Receives bridged assets via Hyperlane, provides instant liquidity, and deposits idle funds into yield pools. ### OriginSettings Configuration for an authorized origin chain and bridge #### Parameters | Name | Type | Description | |------------|--------|---------------------------------------------------------------------------------------------------------------| | chainId | uint32 | The ID of the blockchain chain. | | bridge | address| The bridge address to interact with. | | curator | address| Address of the designated curator for managing this origin. | | maxDebt | uint256| The maximum debt the origin can accumulate. | | outstandingDebt | uint256 | The current outstanding debt of the origin. | | proxyBridge | address| A proxy bridge address, if applicable. | | bridgeFee | uint32 | The fee charged by the bridge for transactions. | | coolDown | uint32 | Time period required before a bridge can be used again after it has been utilized. | ```solidity struct OriginSettings { uint32 chainId; address bridge; address curator; uint256 maxDebt; uint256 outstandingDebt; address proxyBridge; uint32 bridgeFee; uint32 coolDown; } ``` ### OriginParam Parameters for adding a new origin #### Parameters | Name | Type | Description | |-----------|--------|---------------------------------------------------------------------------------------------------------| | curator | address| The curator managing the new origin. | | chainId | uint32 | The ID of the blockchain chain for the new origin. | | bridge | address| The bridge address for this origin. | | proxyBridge | address| A proxy bridge address, if applicable. | | maxDebt | uint256| The maximum debt allowed for this origin. | | bridgeFee | uint32 | The fee charged by the bridge for this origin. | | coolDown | uint32 | Time period required before this origin can be utilized again after it has been used. | ```solidity struct OriginParam { address curator; uint32 chainId; address bridge; address proxyBridge; uint256 maxDebt; uint32 bridgeFee; uint32 coolDown; } ``` ### UnauthorizedCaller ```solidity error UnauthorizedCaller(address sender) ``` Error when the caller is not authorized for the operation. #### Parameters | Name | Type | Description | |--------|--------|---------------------------------------------------| | sender | address| The address that attempted the unauthorized call. | ### UnauthorizedSwap ```solidity error UnauthorizedSwap(address token) ``` Error when attempting to swap the pool’s underlying asset. #### Parameters | Name | Type | Description | |--------|--------|--------------------------------------------------| | token | address| The token address that was attempted to be swapped. | ### UnauthorizedOrigin ```solidity error UnauthorizedOrigin(uint32 chainId, address bridge) ``` Error when a message is from an unauthorized origin. #### Parameters | Name | Type | Description | |---------|--------|-------------------------------------------------------------------------| | chainId | uint32 | The chain ID of the unauthorized origin. | | bridge | address| The bridge address of the unauthorized origin. | ### MessageAlreadyProcessed ```solidity error MessageAlreadyProcessed(uint32 chainId, address bridge, uint256 nonce) ``` Error when attempting to process an already processed message. #### Parameters | Name | Type | Description | |----------|--------|-------------------------------------------------------------| | chainId | uint32 | The chain ID of the message origin. | | bridge | address| The bridge address of the message origin. | | nonce | uint256| The nonce of the already processed message. | ### TooMuchDebtFromOrigin ```solidity error TooMuchDebtFromOrigin(uint32 chainId, address bridge, uint256 maxDebt, uint256 nonce, address recipient, uint256 amount) ``` Error when the origin would exceed its maximum allowed debt. #### Parameters | Name | Type | Description | |-----------|--------|--------------------------------------------------------------------------| | chainId | uint32 | The chain ID of the origin. | | bridge | address| The bridge address of the origin. | | maxDebt | uint256| The maximum allowed debt for this origin. | | nonce | uint256| The nonce of the rejected transaction. | | recipient | address| The intended recipient of the funds. | | amount | uint256| The amount that would exceed the debt limit. | ### FailedTransfer ```solidity error FailedTransfer(address recipient, uint256 amount) ``` Error when native currency transfer fails. #### Parameters | Name | Type | Description | |-----------|--------|-------------------------------------------------------| | recipient | address| The intended recipient of the transfer. | | amount | uint256| The amount that failed to transfer. | ### InsufficientFunds ```solidity error InsufficientFunds(uint256 amount, uint256 balance) ``` Error when insufficient funds are available. #### Parameters | Name | Type | Description | |---------|----------|-----------------------------------------------------------------| | amount | uint256 | The amount available. | | balance | uint256 | The balance required. | ### NotAWethPool ```solidity error NotAWethPool() ``` Error when native currency is sent to a non-WETH pool. ### MessageTooRecent ```solidity error MessageTooRecent(uint32 chainId, address bridge, uint256 nonce, uint256 timestamp, uint32 coolDown) ``` Error when message timestamp is too recent based on cooldown period. #### Parameters | Name | Type | Description | |-----------|----------|-----------------------------------------------------------------| | chainId | uint32 | The chain ID of the message origin. | | bridge | address | The bridge address of the message origin. | | nonce | uint256 | The nonce of the message. | | timestamp | uint256 | The timestamp of the message. | | coolDown | uint32 | The required cooldown period. | ### SharePriceTooLow ```solidity error SharePriceTooLow(uint256 actualPrice, uint256 minPrice) ``` Error when share price is below minimum acceptable threshold. #### Parameters | Name | Type | Description | |---------------|----------|-------------------------------------------------------------| | actualPrice | uint256 | The actual share price. | | minPrice | uint256 | The minimum acceptable share price. | ### SharePriceTooHigh ```solidity error SharePriceTooHigh(uint256 actualPrice, uint256 maxPrice) ``` Error when share price is above maximum acceptable threshold. #### Parameters | Name | Type | Description | |---------------|----------|-------------------------------------------------------------| | actualPrice | uint256 | The actual share price. | | maxPrice | uint256 | The maximum acceptable share price. | ### HYPERLANE_MAILBOX ```solidity address HYPERLANE_MAILBOX ``` The address of the Hyperlane mailbox. Used to receive cross-chain messages. ### WETH ```solidity address WETH ``` The address of the WETH contract (used for native pools). Set to WETH address for native currency pools, otherwise can be address(0). ### FRACTIONAL_BPS_DENOMINATOR ```solidity uint256 FRACTIONAL_BPS_DENOMINATOR ``` Denominator for fractional basis points calculations (1 = 0.0000001 bps). ### outstandingDebt ```solidity uint256 outstandingDebt ``` Keeping track of the outstanding debt for ERC4626 computations. Represents funds that have been sent but not yet claimed from bridges. ### authorizedOrigins ```solidity mapping(uint32 => mapping(address => struct RelayPool.OriginSettings)) authorizedOrigins ``` Mapping of origins to their settings: [chainId][bridgeAddress] => OriginSettings. ### messages ```solidity mapping(uint32 => mapping(address => mapping(uint256 => bytes))) messages ``` Mapping of messages by origin: [chainId][bridgeAddress][nonce] => message data. ### yieldPool ```solidity address yieldPool ``` The address of the yield pool where funds are deposited. Must be an ERC4626 vault for the same underlying asset. ### tokenSwapAddress ```solidity address tokenSwapAddress ``` UniswapV3 wrapper contract for token swaps. ### pendingBridgeFees ```solidity uint256 pendingBridgeFees ``` Keeping track of the total fees collected. Fees are held in the yield pool until they finish streaming. ### totalAssetsToStream ```solidity uint256 totalAssetsToStream ``` All incoming assets are streamed (even though they are instantly deposited in the yield pool). Total amount of assets currently being streamed. ### lastAssetsCollectedAt ```solidity uint256 lastAssetsCollectedAt ``` Timestamp when assets were last collected for streaming. ### endOfStream ```solidity uint256 endOfStream ``` Timestamp when the current streaming period ends. ### streamingPeriod ```solidity uint256 streamingPeriod ``` Duration over which collected assets are streamed. ### LoanEmitted ```solidity event LoanEmitted(uint256 nonce, address recipient, contract ERC20 asset, uint256 amount, struct RelayPool.OriginSettings origin, uint256 fees) ``` Emitted when a loan is provided to a bridge recipient. #### Parameters | Name | Type | Description | |---------|----------|----------------------------------------------------------------------------| | nonce | uint256 | The unique identifier of the transaction. | | recipient | address| The address receiving the funds. | | asset | contract ERC20 | The asset being transferred. | | amount | uint256 | The total amount including fees. | | origin | struct RelayPool.OriginSettings | The origin settings for this bridge. | | fees | uint256 | The fee amount collected. | ### BridgeCompleted ```solidity event BridgeCompleted(uint32 chainId, address bridge, uint256 amount, uint256 fees) ``` Emitted when bridged funds are claimed and deposited. #### Parameters | Name | Type | Description | |---------|----------|-------------------------------------------------------------------------| | chainId | uint32 | The chain ID of the bridge origin. | | bridge | address | The bridge address on the origin chain. | | amount | uint256 | The total amount claimed. | | fees | uint256 | The fee amount collected. | ### OutstandingDebtChanged ```solidity event OutstandingDebtChanged(uint256 oldDebt, uint256 newDebt, struct RelayPool.OriginSettings origin, uint256 oldOriginDebt, uint256 newOriginDebt) ``` Emitted when outstanding debt changes. #### Parameters | Name | Type | Description | |-----------------|----------|--------------------------------------------------------------| | oldDebt | uint256 | Previous total outstanding debt. | | newDebt | uint256 | New total outstanding debt. | | origin | struct RelayPool.OriginSettings | The origin settings involved. | | oldOriginDebt | uint256 | Previous outstanding debt for the origin. | | newOriginDebt | uint256 | New outstanding debt for the origin. | ### AssetsDepositedIntoYieldPool ```solidity event AssetsDepositedIntoYieldPool(uint256 amount, address yieldPool) ``` Emitted when assets are deposited into the yield pool. #### Parameters | Name | Type | Description | |-----------|----------|-------------------------------------------------------------| | amount | uint256 | The amount deposited. | | yieldPool | address | The yield pool address. | ### AssetsWithdrawnFromYieldPool ```solidity event AssetsWithdrawnFromYieldPool(uint256 amount, address yieldPool) ``` Emitted when assets are withdrawn from the yield pool. #### Parameters | Name | Type | Description | |-----------|----------|-------------------------------------------------------------| | amount | uint256 | The amount withdrawn. | | yieldPool | address | The yield pool address. | ### TokenSwapChanged ```solidity event TokenSwapChanged(address prevAddress, address newAddress) ``` Emitted when the token swap address is changed. #### Parameters | Name | Type | Description | |--------------|----------|--------------------------------------------------------| | prevAddress | address | The previous swap contract address. | | newAddress | address | The new swap contract address. | ### YieldPoolChanged ```solidity event YieldPoolChanged(address oldPool, address newPool) ``` Emitted when the yield pool is changed. #### Parameters | Name | Type | Description | |-----------|----------|------------------------------------------------------------| | oldPool | address | The previous yield pool address. | | newPool | address | The new yield pool address. | ### StreamingPeriodChanged ```solidity event StreamingPeriodChanged(uint256 oldPeriod, uint256 newPeriod) ``` Emitted when the streaming period is changed. #### Parameters | Name | Type | Description | |-----------|----------|------------------------------------------------------------| | oldPeriod | uint256 | The previous streaming period. | | newPeriod | uint256 | The new streaming period. | ### OriginAdded ```solidity event OriginAdded(struct RelayPool.OriginParam origin) ``` Emitted when a new origin is added. #### Parameters | Name | Type | Description | |--------|----------|--------------------------------------------------------| | origin | struct RelayPool.OriginParam | The origin parameters. | ### OriginDisabled ```solidity event OriginDisabled(uint32 chainId, address bridge, uint256 maxDebt, uint256 outstandingDebt, address proxyBridge) ``` Emitted when an origin is disabled. #### Parameters | Name | Type | Description | |-----------------|----------|--------------------------------------------------------------| | chainId | uint32 | The chain ID of the disabled origin. | | bridge | address | The bridge address of the disabled origin. | | maxDebt | uint256 | The previous maximum debt limit. | | outstandingDebt | uint256 | The outstanding debt at the time of disabling. | | proxyBridge | address | The proxy bridge address. | ### Constructor ```solidity constructor(address hyperlaneMailbox, contract ERC20 asset, string name, string symbol, address baseYieldPool, address weth, address curator) public ``` Initializes the RelayPool with core parameters. Warning: the owner should always be a timelock with significant delay. #### Parameters | Name | Type | Description | |----------------------|----------|--------------------------------------------------------| | hyperlaneMailbox | address | The Hyperlane mailbox contract address. | | asset | contract ERC20 | The underlying asset for this vault. | | name | string | The name of the vault token. | | symbol | string | The symbol of the vault token. | | baseYieldPool | address | The initial yield pool for depositing assets. | | weth | address | The WETH contract address (for native currency pools).| | curator | address | The address that will own the pool after deployment. | ### updateStreamingPeriod ```solidity function updateStreamingPeriod(uint256 newPeriod) public ``` Updates the streaming period for fee accrual. Updates streamed assets before changing the period. #### Parameters | Name | Type | Description | |-----------|----------|------------------------------------------------------------| | newPeriod | uint256 | The new streaming period in seconds. | ### updateYieldPool ```solidity function updateYieldPool(address newPool, uint256 minSharePriceFromOldPool, uint256 maxSharePricePriceFromNewPool) public ``` Updates the yield pool, moving all assets from the old pool to the new one. Implements share price-based slippage protection to ensure fair value transfer. #### Parameters | Name | Type | Description | |-------------------------------|----------|---------------------------------------------------------------| | newPool | address | The address of the new yield pool. | | minSharePriceFromOldPool | uint256 | The minimum acceptable share price when withdrawing from the old pool. | | maxSharePricePriceFromNewPool | uint256 | The maximum acceptable share price when depositing into the new pool. | ### addOrigin ```solidity function addOrigin(struct RelayPool.OriginParam origin) public ``` Adds a new authorized origin for bridging. Only callable by owner, typically a timelock contract. #### Parameters | Name | Type | Description | |--------|----------|------------------------------------------------------------| | origin | struct RelayPool.OriginParam | The origin parameters including chain ID, addresses, and limits. | ### disableOrigin ```solidity function disableOrigin(uint32 chainId, address bridge) public ``` Disables an origin by setting its max debt to zero. Only callable by the origin’s curator for emergency response. #### Parameters | Name | Type | Description | |-----------|----------|-------------------------------------------------------------| | chainId | uint32 | The chain ID of the origin to disable. | | bridge | address | The bridge address of the origin to disable. | ### increaseOutstandingDebt ```solidity function increaseOutstandingDebt(uint256 amount, struct RelayPool.OriginSettings origin) internal ``` Increases outstanding debt for an origin. Updates both origin-specific and total outstanding debt. #### Parameters | Name | Type | Description | |-----------|----------|-------------------------------------------------------------------| | amount | uint256 | The amount to increase debt by. | | origin | struct RelayPool.OriginSettings | The origin settings to update. | ### decreaseOutstandingDebt ```solidity function decreaseOutstandingDebt(uint256 amount, struct RelayPool.OriginSettings origin) internal ``` Decreases outstanding debt for an origin. Updates both origin-specific and total outstanding debt. #### Parameters | Name | Type | Description | |-----------|----------|-------------------------------------------------------------------| | amount | uint256 | The amount to decrease debt by. | | origin | struct RelayPool.OriginSettings | The origin settings to update. | ### maxDeposit ```solidity function maxDeposit(address) public view returns (uint256 maxAssets) ``` Returns the maximum assets that can be deposited. Limited by the yield pool’s capacity. #### Parameters | Name | Type | Description | |---------|------------|---------------------------------| | | address | The address from which assets can be deposited. | #### Return Values | Name | Type | Description | |-----------|----------|------------------------------------------------------------| | maxAssets | uint256 | The maximum amount of assets that can be deposited. | ### maxWithdraw ```solidity function maxWithdraw(address owner) public view returns (uint256 maxAssets) ``` Returns the maximum assets that can be withdrawn by an owner. Limited to the owner’s share balance converted to assets. #### Parameters | Name | Type | Description | |---------|------------|----------------------------------| | owner | address | The address to check withdrawal capacity for. | #### Return Values | Name | Type | Description | |-----------|----------|------------------------------------------------------------| | maxAssets | uint256 | The maximum amount of assets that can be withdrawn. | ### maxMint ```solidity function maxMint(address receiver) public view returns (uint256 maxShares) ``` Returns the maximum shares that can be minted. Limited by the yield pool’s deposit capacity. #### Parameters | Name | Type | Description | |-----------|------------|--------------------------------------| | receiver | address | The address that would receive the shares. | #### Return Values | Name | Type | Description | |-----------|----------|------------------------------------------------------------| | maxShares | uint256 | The maximum amount of shares that can be minted. | ### maxRedeem ```solidity function maxRedeem(address owner) public view returns (uint256 maxShares) ``` Returns the maximum shares that can be redeemed by an owner. Limited by the owner’s share balance and yield pool’s withdrawal capacity. #### Parameters | Name | Type | Description | |-----------|------------|--------------------------------| | owner | address | The address to check redemption capacity for. | #### Return Values | Name | Type | Description | |-----------|----------|------------------------------------------------------------| | maxShares | uint256 | The maximum amount of shares that can be redeemed. | ### totalAssets ```solidity function totalAssets() public view returns (uint256) ``` Returns the total assets controlled by the pool. Includes yield pool balance, outstanding debt, minus pending fees and streaming assets. #### Return Values | Name | Type | Description | |-----------|----------|------------------------------------------------------------------| | [0] | uint256 | The total assets under management. | ### depositAssetsInYieldPool ```solidity function depositAssetsInYieldPool(uint256 amount) internal ``` Deposits assets into the yield pool. Internal function that approves and deposits to yield pool. #### Parameters | Name | Type | Description | |---------|------------|----------------------------------| | amount | uint256 | The amount of assets to deposit. | ### withdrawAssetsFromYieldPool ```solidity function withdrawAssetsFromYieldPool(uint256 amount, address recipient) internal ``` Withdraws assets from the yield pool. Internal function that withdraws from yield pool to recipient. #### Parameters | Name | Type | Description | |-----------|------------|----------------------------------------| | amount | uint256 | The amount of assets to withdraw. | | recipient | address | The address to receive the withdrawn assets. | ### handle ```solidity function handle(uint32 chainId, bytes32 bridgeAddress, bytes data) external payable ``` Handles incoming cross-chain messages from Hyperlane. Only callable by Hyperlane mailbox, provides instant liquidity to recipients. #### Parameters | Name | Type | Description | |---------------|-----------|---------------------------------------------| | chainId | uint32 | The origin chain ID. | | bridgeAddress | bytes32 | The origin bridge address (as bytes32). | | data | bytes | The encoded message data. | ### remainsToStream ```solidity function remainsToStream() internal view returns (uint256) ``` Calculates remaining assets to be streamed. Returns zero if the streaming period has ended. #### Return Values | Name | Type | Description | |-----------|-----------|-------------------------------------------------| | [0] | uint256 | The amount of assets remaining to be streamed. | ### updateStreamedAssets ```solidity function updateStreamedAssets() public returns (uint256) ``` Updates the streamed assets calculation. Resets the streaming calculation to current timestamp. #### Return Values | Name | Type | Description | |-----------|-----------|-------------------------------------------------| | [0] | uint256 | The new total assets to stream. | ### addToStreamingAssets ```solidity function addToStreamingAssets(uint256 amount) internal returns (uint256) ``` Adds assets to be accounted for in a streaming fashion. Adjusts streaming end time based on weighted average. #### Parameters | Name | Type | Description | |---------|-----------|-------------------------------------| | amount | uint256 | The amount of assets to add to streaming. | #### Return Values | Name | Type | Description | |-----------|-----------|-------------------------------------------------| | [0] | uint256 | The new total assets to stream. | ### claim ```solidity function claim(uint32 chainId, address bridge) public returns (uint256 amount) ``` Claims funds from a bridge after they arrive. Decreases outstanding debt and deposits funds into yield pool. #### Parameters | Name | Type | Description | |-----------|-----------|-------------------------------------------------------------| | chainId | uint32 | The origin chain ID. | | bridge | address | The origin bridge address. | #### Return Values | Name | Type | Description | |-----------|-----------|-------------------------------------------------------| | amount | uint256 | The amount of assets claimed. | ### sendFunds ```solidity function sendFunds(uint256 amount, address recipient) internal ``` Sends funds to a recipient. Handles both ERC20 and native currency transfers. #### Parameters | Name | Type | Description | |-----------|-----------|---------------------------------------------------| | amount | uint256 | The amount to send. | | recipient | address | The address to receive the funds. | ### setTokenSwap ```solidity function setTokenSwap(address newTokenSwapAddress) external ``` Sets the token swap contract address. Used for swapping non-asset tokens received by the pool. #### Parameters | Name | Type | Description | |----------------------|----------|---------------------------------------------------| | newTokenSwapAddress | address | The new token swap contract address. | ### swapAndDeposit ```solidity function swapAndDeposit(address token, uint256 amount, uint24 uniswapWethPoolFeeToken, uint24 uniswapWethPoolFeeAsset, uint48 deadline, uint256 amountOutMinimum) public ``` Swaps tokens and deposits resulting assets. Swaps via Uniswap V3 through the token swap contract. #### Parameters | Name | Type | Description | |---------------------------|----------|---------------------------------------------------| | token | address | The token to swap from. | | amount | uint256 | The amount of tokens to swap. | | uniswapWethPoolFeeToken | uint24 | The fee tier for token-WETH pool. | | uniswapWethPoolFeeAsset | uint24 | The fee tier for WETH-asset pool. | | deadline | uint48 | The deadline for the swap. | | amountOutMinimum | uint256 | The minimum amount of assets to receive. | ### collectNonDepositedAssets ```solidity function collectNonDepositedAssets() public ``` Collects any assets not yet deposited and starts streaming them. Can be called by anyone to ensure timely asset collection. ### beforeWithdraw ```solidity function beforeWithdraw(uint256 assets, uint256) internal ``` Hook called before withdrawing assets from the vault. Withdraws assets from yield pool before processing withdrawal. #### Parameters | Name | Type | Description | |---------|-----------|---------------------------------------------------| | assets | uint256 | The amount of assets to withdraw. | | | uint256 | | ### afterDeposit ```solidity function afterDeposit(uint256 assets, uint256) internal ``` Hook called after depositing assets to the vault. Deposits assets into yield pool after receiving them. #### Parameters | Name | Type | Description | |---------|-----------|---------------------------------------------------| | assets | uint256 | The amount of assets deposited. | | | uint256 | | ### processFailedHandler ```solidity function processFailedHandler(uint32 chainId, address bridge, bytes data) public ``` Processes failed Hyperlane messages manually. Only callable by owner, typically after slow bridge resolution. #### Parameters | Name | Type | Description | |-----------|-----------|---------------------------------------------------| | chainId | uint32 | The origin chain ID. | | bridge | address | The origin bridge address. | | data | bytes | The encoded message data. | ### receive ```solidity receive() external payable ``` Receives native currency. Required for WETH unwrapping in native currency pools.