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ChainlinkFlightRatingsOracleDemo.sol

// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.6.0;

import "https://github.com/smartcontractkit/chainlink/evm-contracts/src/v0.6/ChainlinkClient.sol";
import "https://github.com/smartcontractkit/chainlink/evm-contracts/src/v0.6/vendor/Ownable.sol";

/*
 *  This is a demo of the Chainlink FlightRatings Oracle.
 *  To demonstrate, follow these steps: 
 *  
 *  1) Compile the contract
 *  2) Deploy the contract to xDai Chain
 *  3) Call the requestRatingsOracle function
 *  4) A short time later, the oracle will call back the fullfillRatingsOracle function with the result.
 *
 */



contract ChainlinkFlightRatingsOracleDemo is ChainlinkClient, Ownable {
  uint256 constant private ORACLE_PAYMENT = 0 * LINK;

  address oracle = 0xa68bC2d344f69F34f5A7cbb5233f9bF1a270B2f6;
  // string jobId = "d62ca345ab9443ddbe9087560f7e833b";

  bytes32 public ratings;


  event RequestRatingsOracleFulfilled(
    bytes32 indexed requestId,
    bytes32 ratings
  );


  constructor() public Ownable() {
    setChainlinkToken(0xE2e73A1c69ecF83F464EFCE6A5be353a37cA09b2);
    
  }

  function requestRatingsOracle()
    public
    onlyOwner
  {
    
    Chainlink.Request memory req = buildChainlinkRequest(
        stringToBytes32('e67eb5a4072b48ba881863f1b9b57fab'), 
        address(this), 
        this.fulfillRatingsOracle.selector
        );
    
    req.add("extPath", "LH/117"); // replace this with Carrier/FlightNumber combination of your choice
    
    sendChainlinkRequestTo(oracle, req, ORACLE_PAYMENT);
    
  }


  function fulfillRatingsOracle(bytes32 _requestId, bytes32 _ratings)
    public
    recordChainlinkFulfillment(_requestId)
  {
    ratings = _ratings;
    emit RequestRatingsOracleFulfilled(_requestId, _ratings);
  }

  function stringToBytes32(string memory source) private pure returns (bytes32 result) {
    bytes memory tempEmptyStringTest = bytes(source);
    if (tempEmptyStringTest.length == 0) {
      return 0x0;
    }

    assembly { // solhint-disable-line no-inline-assembly
      result := mload(add(source, 32))
    }
  }

}