ConsumerAPI.sol

// SPDX-License-Identifier: MIT
pragma solidity 0.8.7;


import "@chainlink/contracts/src/v0.8/ChainlinkClient.sol";
import "@chainlink/contracts/src/v0.8/ConfirmedOwner.sol";


contract APIConsumer is ChainlinkClient, ConfirmedOwner {
   using Chainlink for Chainlink.Request;


   uint256 public volume;
   bytes32 private jobId;
   uint256 private fee;


   event RequestVolume(bytes32 indexed requestId, uint256 volume);


   /**
    * @notice Initialise the link token and target oracle
    *
    * Sepolia Testnet details:
    * Link Token: 0x779877A7B0D9E8603169DdbD7836e478b4624789
    * Oracle: 0x6090149792dAAeE9D1D568c9f9a6F6B46AA29eFD (Chainlink DevRel)
    * jobId: ca98366cc7314957b8c012c72f05aeeb
    *
    */
   constructor() ConfirmedOwner(msg.sender) {
       setChainlinkToken(0x779877A7B0D9E8603169DdbD7836e478b4624789);
       setChainlinkOracle(0x6090149792dAAeE9D1D568c9f9a6F6B46AA29eFD);
       jobId = "ca98366cc7314957b8c012c72f05aeeb";
       fee = (1 * LINK_DIVISIBILITY) / 10; // 0,1 * 10**18 (Varies by network and job)
   }


   /**
    * Create a Chainlink request to retrieve API response, find the target
    * data, then multiply by 1000000000000000000 (to remove decimal places from data).
    */
   function requestVolumeData() public returns (bytes32 requestId) {
       Chainlink.Request memory req = buildChainlinkRequest(
           jobId,
           address(this),
           this.fulfill.selector
       );


       // Set the URL to perform the GET request on
       req.add(
           "get",
           "https://min-api.cryptocompare.com/data/pricemultifull?fsyms=ETH&tsyms=USD"
       );


       // Set the path to find the desired data in the API response, where the response format is:
       // {"RAW":
       //   {"ETH":
       //    {"USD":
       //     {
       //      "VOLUME24HOUR": xxx.xxx,
       //     }
       //    }
       //   }
       //  }
       // request.add("path", "RAW.ETH.USD.VOLUME24HOUR"); // Chainlink nodes prior to 1.0.0 support this format
       req.add("path", "RAW,ETH,USD,VOLUME24HOUR"); // Chainlink nodes 1.0.0 and later support this format


       // Multiply the result by 1000000000000000000 to remove decimals
       int256 timesAmount = 10 ** 18;
       req.addInt("times", timesAmount);


       // Sends the request
       return sendChainlinkRequest(req, fee);
   }


   /**
    * Receive the response in the form of uint256
    */
   function fulfill(
       bytes32 _requestId,
       uint256 _volume
   ) public recordChainlinkFulfillment(_requestId) {
       emit RequestVolume(_requestId, _volume);
       volume = _volume;
   }


   /**
    * Allow withdraw of Link tokens from the contract
    */
   function withdrawLink() public onlyOwner {
       LinkTokenInterface link = LinkTokenInterface(chainlinkTokenAddress());
       require(
           link.transfer(msg.sender, link.balanceOf(address(this))),
           "Unable to transfer"
       );
   }
}