AssetPriceConsumer.sol

pragma solidity ^0.4.23;

import "../Chainlinked.sol";
import "openzeppelin-solidity/contracts/ownership/Ownable.sol";

contract SpecAndRunRequester is Chainlinked, Ownable {

  event RequestFulfilled(
    bytes32 indexed requestId,
    bytes32 indexed price
  );

  mapping(bytes32 => bytes32) requests;
  mapping(bytes32 => bytes32) prices;

  constructor(address _link, address _oracle) Ownable() public {
    setLinkToken(_link);
    setOracle(_oracle);
  }

  function requestPrice(string _base, string _quote) public {
    string[] memory tasks = new string[](4);
    tasks[0] = "assetprice";
    tasks[1] = "copy";
    tasks[2] = "ethuint256";
    tasks[3] = "ethtx";

    ChainlinkLib.Spec memory spec = newSpec(tasks, this, "fulfill(bytes32,bytes32)");
    spec.add("base", _base);
    spec.add("quote", _quote);

    string[] memory path = new string[](1);
    path[0] = "price";
    spec.addStringArray("copyPath", path);
    requests[chainlinkRequest(spec, LINK(1))] = keccak256(_base, _quote);
  }

  function cancelRequest(bytes32 _requestId) public onlyOwner {
    cancelChainlinkRequest(_requestId);
  }

  function fulfill(bytes32 _requestId, bytes32 _price)
    public
    checkChainlinkFulfillment(_requestId)
  {
    emit RequestFulfilled(_requestId, _price);
    prices[requests[_requestId]] = _price;
  }

}