# ChainlinkClientUtils

\_Chainlink client refactored into library and all unused functions removed Uses price aggregator facet of multi collat diamond for storage.

Copy of <https://github.com/smartcontractkit/chainlink/blob/contracts-v0.5.1/contracts/src/v0.8/ChainlinkClient.sol> with only `requestCount` changed to unset so as to be inherited by a proxy implementation.\_

## ChainlinkRequested

```solidity
event ChainlinkRequested(bytes32 id)
```

## ChainlinkFulfilled

```solidity
event ChainlinkFulfilled(bytes32 id)
```

## \_getSlot

```solidity
function _getSlot() internal pure returns (uint256)
```

*Returns storage slot to use when fetching storage relevant to library*

## \_getStorage

```solidity
function _getStorage() internal pure returns (struct IPriceAggregator.PriceAggregatorStorage s)
```

*Returns storage pointer for storage struct in diamond contract, at defined slot*

## buildChainlinkRequest

```solidity
function buildChainlinkRequest(bytes32 specId, address callbackAddr, bytes4 callbackFunctionSignature) internal pure returns (struct Chainlink.Request)
```

Creates a request that can hold additional parameters

### Parameters

| Name                      | Type    | Description                                                   |
| ------------------------- | ------- | ------------------------------------------------------------- |
| specId                    | bytes32 | The Job Specification ID that the request will be created for |
| callbackAddr              | address | address to operate the callback on                            |
| callbackFunctionSignature | bytes4  | function signature to use for the callback                    |

### Return Values

| Name | Type                     | Description                          |
| ---- | ------------------------ | ------------------------------------ |
| \[0] | struct Chainlink.Request | A Chainlink Request struct in memory |

## sendChainlinkRequestTo

```solidity
function sendChainlinkRequestTo(address oracleAddress, struct Chainlink.Request req, uint256 payment) internal returns (bytes32 requestId)
```

Creates a Chainlink request to the specified oracle address

*Generates and stores a request ID, increments the local nonce, and uses `transferAndCall` to send LINK which creates a request on the target oracle contract. Emits ChainlinkRequested event.*

### Parameters

| Name          | Type                     | Description                                |
| ------------- | ------------------------ | ------------------------------------------ |
| oracleAddress | address                  | The address of the oracle for the request  |
| req           | struct Chainlink.Request | The initialized Chainlink Request          |
| payment       | uint256                  | The amount of LINK to send for the request |

### Return Values

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

## setChainlinkToken

```solidity
function setChainlinkToken(address _linkErc677) internal
```

Sets the LINK token address

### Parameters

| Name         | Type    | Description                            |
| ------------ | ------- | -------------------------------------- |
| \_linkErc677 | address | The address of the LINK token contract |

## validateChainlinkCallback

```solidity
function validateChainlinkCallback(bytes32 requestId) internal
```

Ensures that the fulfillment is valid for this contract

*Use if the contract developer prefers methods instead of modifiers for validation*

### Parameters

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

## recordChainlinkFulfillment

```solidity
modifier recordChainlinkFulfillment(bytes32 requestId)
```

*Reverts if the sender is not the oracle of the request. Emits ChainlinkFulfilled event.*

### Parameters

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