FunctionsClient API Reference

Consumer contract developers inherit FunctionsClient to create Chainlink Functions requests.

Events

RequestSent

event RequestSent(bytes32 id)

RequestFulfilled

event RequestFulfilled(bytes32 id)

Errors

SenderIsNotRegistry

error SenderIsNotRegistry()

RequestIsAlreadyPending

error RequestIsAlreadyPending()

RequestIsNotPending

error RequestIsNotPending()

Methods

constructor

constructor(address oracle)

getDONPublicKey

function getDONPublicKey() external view returns (bytes)

Returns the DON's secp256k1 public key used to encrypt secrets

All Oracles nodes have the corresponding private key needed to decrypt the secrets encrypted with the public key

Return Values

| Name | Type | Description | | ---- | ----- | -------------------------- | | [0] | bytes | publicKey DON's public key |

estimateCost

function estimateCost(struct Functions.Request req, uint64 subscriptionId, uint32 gasLimit, uint256 gasPrice) public view returns (uint96)

Estimate the total cost that will be charged to a subscription to make a request: gas re-imbursement, plus DON fee, plus Registry fee

Parameters

| Name | Type | Description | | -------------- | ------------------------ | -------------------------------------- | | req | struct Functions.Request | The initialized Functions.Request | | subscriptionId | uint64 | The subscription ID | | gasLimit | uint32 | gas limit for the fulfillment callback | | gasPrice | uint256 | |

Return Values

| Name | Type | Description | | ---- | ------ | --------------------------------------- | | [0] | uint96 | billedCost Cost in Juels (1e18) of LINK |

sendRequest

function sendRequest(struct Functions.Request req, uint64 subscriptionId, uint32 gasLimit) internal returns (bytes32)

Sends a Chainlink Functions request to the stored oracle address

Parameters

| Name | Type | Description | | -------------- | ------------------------ | -------------------------------------- | | req | struct Functions.Request | The initialized Functions.Request | | subscriptionId | uint64 | The subscription ID | | gasLimit | uint32 | gas limit for the fulfillment callback |

Return Values

| Name | Type | Description | | ---- | ------- | ---------------------------------- | | [0] | bytes32 | requestId The generated request ID |

fulfillRequest

function fulfillRequest(bytes32 requestId, bytes response, bytes err) internal virtual

User defined function to handle a response

Parameters

| Name | Type | Description | | --------- | ------- | --------------------------------------------------------------------------------------------------------------------------------- | | requestId | bytes32 | The request ID, returned by sendRequest() | | response | bytes | Aggregated response from the user code | | err | bytes | Aggregated error from the user code or from the execution pipeline Either response or error parameter will be set, but never both |

handleOracleFulfillment

function handleOracleFulfillment(bytes32 requestId, bytes response, bytes err) external

Chainlink Functions response handler called by the designated transmitter node in an OCR round.

Parameters

| Name | Type | Description | | --------- | ------- | ------------------------------------------------------------------------------------------------------------------------------------------ | | requestId | bytes32 | The requestId returned by FunctionsClient.sendRequest(). | | response | bytes | Aggregated response from the user code. | | err | bytes | Aggregated error either from the user code or from the execution pipeline. Either response or error parameter will be set, but never both. |

setOracle

function setOracle(address oracle) internal

Sets the stored Oracle address

Parameters

| Name | Type | Description | | ------ | ------- | ---------------------------------------- | | oracle | address | The address of Functions Oracle contract |

getChainlinkOracleAddress

function getChainlinkOracleAddress() internal view returns (address)

Gets the stored address of the oracle contract

Return Values

| Name | Type | Description | | ---- | ------- | ---------------------------------- | | [0] | address | The address of the oracle contract |

addExternalRequest

function addExternalRequest(address oracleAddress, bytes32 requestId) internal

Allows for a request which was created on another contract to be fulfilled on this contract

Parameters

| Name | Type | Description | | ------------- | ------- | ---------------------------------------------------------------- | | oracleAddress | address | The address of the oracle contract that will fulfill the request | | requestId | bytes32 | The request ID used for the response |

Modifiers

recordChainlinkFulfillment

modifier recordChainlinkFulfillment(bytes32 requestId)

Reverts if the sender is not the oracle that serviced the request. Emits RequestFulfilled event.

Parameters

| Name | Type | Description | | --------- | ------- | ------------------------------ | | requestId | bytes32 | The request ID for fulfillment |

notPendingRequest

modifier notPendingRequest(bytes32 requestId)

Reverts if the request is already pending

Parameters

| Name | Type | Description | | --------- | ------- | ------------------------------ | | requestId | bytes32 | The request ID for fulfillment |