Finnhub Stock API Oracle Overview

The API is organized around REST. Our API has predictable resource-oriented URLs, accepts form-encoded request bodies, returns JSON-encoded responses, and uses standard HTTP response codes, authentication, and verbs. This is 1 of the most comprehensive financial API available on the market.

This oracle's initial implementation will provide:

• The Quote for a given stock with the endpoint: quote
• The in-date Stock Candles with the endpoint: stock/candle

API responses are packed after executing our adapter and then pushed on-chain.

Steps For Using This Oracle

Write and deploy your Chainlink contract using the network details below

Fund it with LINK.

Call your request method.

Network Details

Ethereum Mainnet

• Payment amount: 3 LINK
• LINK Token address: 0x514910771af9ca656af840dff83e8264ecf986ca
• Oracle Address: 0x2E5F9bA916558C7Dd6C8cEB5071b499218Fec436
• JobID: 8097c0c8a09545b1a11593c3badda016

Ethereum Kovan Testnet

• Payment amount: 1 LINK
• LINK Token address: 0xa36085F69e2889c224210F603D836748e7dC0088
• Oracle Address: 0x5D376D602BA795984c5430BD80401668c195451c
• JobID: 81f2755374114f8aaa426c7224ac2cc2

Ethereum Rinkeby Testnet

• Payment amount: 1 LINK
• LINK Token address: 0x01BE23585060835E02B77ef475b0Cc51aA1e0709
• Oracle Address: 0xE85d10D6440edcACc1478e28CEa9566704fe88Db
• JobID: 061029413a4d48818df70086050bc60e

Tasks

• Finnhub
• Copy
• Multiply
• ETH Uint256
• ETH Transaction

Request Parameters

Endpoint: The real-time Quote and Stock Candles endpoint. Check Finnhub APIs documment

Solidity Example

req.add("endpoint", "quote");

req.add("endpoint", "stock/candle");

Symbol: The stock ticker from Finnhub Stock Symbols api:

Solidity Example

req.add("ticker", "AAPL");

Timestamp: The exact integer timestamp for candle check (stock/candle).

Solidity Example

req.add("timestamp", 1631627048);

Field: The field selected from JSON response.

Solidity Example

req.add("field", "c");

quote

• c: Current price
• d: Change
• dp: Percent change
• h: High price of the day
• l: Low price of the day
• o: Open price of the day
• pc: Previous close price

stock/candle:

• c: List of close prices for returned candles.
• h: List of high prices for returned candles.
• l: List of low prices for returned candles.
• o: List of open prices for returned candles.
• t: List of timestamp for returned candles.
• v: List of volume data for returned candles.

Times: The amount to multiply the result to uint256.

Solidity Example

req.addInt("times", 100); (for close prise c)

Note for Rinkeby and Kovan Test net Jobs:

• Requests on a test net will return only static data for testing purposes. The returned result may not match Finnhub's API value.

• Entities that are working on Rinkeby or Kovan should contact us for service.

Outputs

An unint256 value of JSON response from our API.

Full Solidity contract

// 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);
    constructor() ConfirmedOwner(msg.sender) {
        setChainlinkToken(0x514910771af9ca656af840dff83e8264ecf986ca);
        setChainlinkOracle(0x2E5F9bA916558C7Dd6C8cEB5071b499218Fec436);
        jobId = '8097c0c8a09545b1a11593c3badda016';
        fee = (30 * LINK_DIVISIBILITY) / 10; // 3 * 10**18 (Varies by network and job)
    }

    function requestVolumeData() public returns (bytes32 requestId) {
        Chainlink.Request memory req = buildChainlinkRequest(jobId, address(this), this.fulfill.selector);

        req.add('endpoint', 'quote'); // or stock/candle
        req.add('symbol', 'AAPL');
        req.addInt('timestamp', 1631627048); // Random number for "quote" endpoint or 0000000000
        req.add('field', 'c');               // timestamp will be ignored as "quote" is real-time
        req.addInt('times', 100);            // All fields (endpoint, symbol, timestamp, etc.) are required

        // 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');
    }
}