Gets the symbol from the CoinGeckoAPI

StringTestAPIConsumer.sol

/** This example code is designed to quickly deploy an example contract using Remix.
 *  If you have never used Remix, try our example walkthrough: https://docs.chain.link/docs/example-walkthrough
 *  You will need testnet ETH and LINK.
 *     - Kovan ETH faucet: https://faucet.kovan.network/
 *     - Kovan LINK faucet: https://kovan.chain.link/
 */

pragma solidity ^0.6.0;

import "https://raw.githubusercontent.com/smartcontractkit/chainlink/develop/evm-contracts/src/v0.6/ChainlinkClient.sol";

contract APIConsumer is ChainlinkClient {
  
    bytes32 public symbol;
    
    address private oracle;
    bytes32 private jobId;
    uint256 private fee;
    
    /**
     * Network: Kovan
     * Oracle: Chainlink - 0x2f90A6D021db21e1B2A077c5a37B3C7E75D15b7e
     * Job ID: Chainlink - 29fa9aa13bf1468788b7cc4a500a45b8
     * Fee: 0.1 LINK
     */
    constructor() public {
        setPublicChainlinkToken();
        oracle = 0x2f90A6D021db21e1B2A077c5a37B3C7E75D15b7e;
        jobId = "50fc4215f89443d185b061e5d7af9490";
        fee = 0.1 * 10 ** 18; // 0.1 LINK
    }
    
    /**
     * Create a Chainlink request to retrieve API response, and find the ethereum symbol.
     */
    function requestSymbol() public returns (bytes32 requestId) 
    {
        Chainlink.Request memory request = buildChainlinkRequest(jobId, address(this), this.fulfill.selector);
        
        // Set the URL to perform the GET request on
        request.add("get", "https://api.coingecko.com/api/v3/coins/ethereum?localization=false&tickers=false&market_data=true&community_data=false&developer_data=false&sparkline=false");
        
        // Set the path to find the desired data in the API response, where the response format is:
        // {"symbol":"eth"}
        request.add("path", "symbol");
        
        // Sends the request
        return sendChainlinkRequestTo(oracle, request, fee);
    }
    
    /**
     * Receive the response in the form of uint256
     */ 
    function fulfill(bytes32 _requestId, bytes32 _symbol) public recordChainlinkFulfillment(_requestId)
    {
        symbol = _symbol;
    }
}