See how Chainlink CCIP, Functions, and Automation combine to power a prediction dApp that uses real-time sports data to trigger automatic payouts.
Retrieve Web2 data and store it onchain using Chainlink Functions.
Built using Chainlink Data Streams, this dApp enables you to use low-latency data in your smart contracts.
Create batch-revealed NFT collections powered by Chainlink Automation & VRF.
See how Chainlink CCIP, Functions, and Automation combine to power a prediction dApp that uses real-time sports data to trigger automatic payouts.
pragma solidity ^0.8.7;
import {ResultsConsumer} from "./ResultsConsumer.sol";
import {NativeTokenSender} from "./ccip/NativeTokenSender.sol";
import {AutomationCompatibleInterface} from "@chainlink/contracts/src/v0.8/AutomationCompatible.sol";
struct Config {
address oracle;
address ccipRouter;
address link;
address weth9Token;
address exchangeToken;
address uniswapV3Router;
uint64 subscriptionId;
uint64 destinationChainSelector;
uint32 gasLimit;
bytes secrets;
string source;
}
contract SportsPredictionGame is ResultsConsumer, NativeTokenSender, AutomationCompatibleInterface {
uint256 private constant MIN_WAGER = 0.00001 ether;
uint256 private constant MAX_WAGER = 0.01 ether;
uint256 private constant GAME_RESOLVE_DELAY = 2 hours;
mapping(uint256 => Game) private games;
mapping(address => mapping(uint256 => Prediction[])) private predictions;
mapping(uint256 => bytes32) private pendingRequests;
uint256[] private activeGames;
uint256[] private resolvedGames;
struct Game {
uint256 sportId;
uint256 externalId;
uint256 timestamp;
uint256 homeWagerAmount;
uint256 awayWagerAmount;
bool resolved;
Result result;
}
struct Prediction {
uint256 gameId;
Result result;
uint256 amount;
bool claimed;
}
enum Result {
None,
Home,
Away
}
event GameRegistered(uint256 indexed gameId);
event GameResolved(uint256 indexed gameId, Result result);
event Predicted(address indexed user, uint256 indexed gameId, Result result, uint256 amount);
event Claimed(address indexed user, uint256 indexed gameId, uint256 amount);
error GameAlreadyRegistered();
error TimestampInPast();
error GameNotRegistered();
error GameIsResolved();
error GameAlreadyStarted();
error InsufficientValue();
error ValueTooHigh();
error InvalidResult();
error GameNotResolved();
error GameNotReadyToResolve();
error ResolveAlreadyRequested();
error NothingToClaim();
constructor(
Config memory config
)
ResultsConsumer(config.oracle, config.subscriptionId, config.source, config.secrets, config.gasLimit)
NativeTokenSender(
config.ccipRouter,
config.link,
config.weth9Token,
config.exchangeToken,
config.uniswapV3Router,
config.destinationChainSelector
)
{}
function predict(uint256 gameId, Result result) public payable {
Game memory game = games[gameId];
uint256 wagerAmount = msg.value;
if (game.externalId == 0) revert GameNotRegistered();
if (game.resolved) revert GameIsResolved();
if (game.timestamp < block.timestamp) revert GameAlreadyStarted();
if (wagerAmount < MIN_WAGER) revert InsufficientValue();
if (wagerAmount > MAX_WAGER) revert ValueTooHigh();
if (result == Result.Home) games[gameId].homeWagerAmount = wagerAmount;
else if (result == Result.Away) games[gameId].awayWagerAmount = wagerAmount;
else revert InvalidResult();
predictions[msg.sender][gameId].push(Prediction(gameId, result, wagerAmount, false));
emit Predicted(msg.sender, gameId, result, wagerAmount);
}
function registerAndPredict(uint256 sportId, uint256 externalId, uint256 timestamp, Result result) external payable {
uint256 gameId = _registerGame(sportId, externalId, timestamp);
predict(gameId, result);
}
function claim(uint256 gameId, bool transfer) external {
Game memory game = games[gameId];
address user = msg.sender;
if (!game.resolved) revert GameNotResolved();
uint256 totalWinnings = 0;
Prediction[] memory userPredictions = predictions[user][gameId];
for (uint256 i = 0; i < userPredictions.length; i ) {
Prediction memory prediction = userPredictions[i];
if (prediction.claimed) continue;
if (game.result == Result.None) {
totalWinnings = prediction.amount;
} else if (prediction.result == game.result) {
uint256 winnings = calculateWinnings(gameId, prediction.amount, prediction.result);
totalWinnings = winnings;
}
predictions[user][gameId][i].claimed = true;
}
if (totalWinnings == 0) revert NothingToClaim();
if (transfer) {
_sendTransferRequest(user, totalWinnings);
} else {
payable(user).transfer(totalWinnings);
}
emit Claimed(user, gameId, totalWinnings);
}
function _registerGame(uint256 sportId, uint256 externalId, uint256 timestamp) internal returns (uint256 gameId) {
gameId = getGameId(sportId, externalId);
if (games[gameId].externalId != 0) revert GameAlreadyRegistered();
if (timestamp < block.timestamp) revert TimestampInPast();
games[gameId] = Game(sportId, externalId, timestamp, 0, 0, false, Result.None);
activeGames.push(gameId);
emit GameRegistered(gameId);
}
function _requestResolve(uint256 gameId) internal {
Game memory game = games[gameId];
if (pendingRequests[gameId] != 0) revert ResolveAlreadyRequested();
if (game.externalId == 0) revert GameNotRegistered();
if (game.resolved) revert GameIsResolved();
if (!readyToResolve(gameId)) revert GameNotReadyToResolve();
pendingRequests[gameId] = _requestResult(game.sportId, game.externalId);
}
function _processResult(uint256 sportId, uint256 externalId, bytes memory response) internal override {
uint256 gameId = getGameId(sportId, externalId);
Result result = Result(uint256(bytes32(response)));
_resolveGame(gameId, result);
}
function _resolveGame(uint256 gameId, Result result) internal {
games[gameId].result = result;
games[gameId].resolved = true;
resolvedGames.push(gameId);
_removeFromActiveGames(gameId);
emit GameResolved(gameId, result);
}
function _removeFromActiveGames(uint256 gameId) internal {
uint256 index;
for (uint256 i = 0; i < activeGames.length; i ) {
if (activeGames[i] == gameId) {
index = i;
break;
}
}
for (uint256 i = index; i < activeGames.length - 1; i ) {
activeGames[i] = activeGames[i 1];
}
activeGames.pop();
}
function getGameId(uint256 sportId, uint256 externalId) public pure returns (uint256) {
return (sportId << 128) | externalId;
}
function getGame(uint256 gameId) external view returns (Game memory) {
return games[gameId];
}
function getActiveGames() public view returns (Game[] memory) {
Game[] memory activeGamesArray = new Game[](activeGames.length);
for (uint256 i = 0; i < activeGames.length; i ) {
activeGamesArray[i] = games[activeGames[i]];
}
return activeGamesArray;
}
function getActivePredictions(address user) external view returns (Prediction[] memory) {
uint256 totalPredictions = 0;
for (uint256 i = 0; i < activeGames.length; i ) {
totalPredictions = predictions[user][activeGames[i]].length;
}
uint256 index = 0;
Prediction[] memory userPredictions = new Prediction[](totalPredictions);
for (uint256 i = 0; i < activeGames.length; i ) {
Prediction[] memory gamePredictions = predictions[user][activeGames[i]];
for (uint256 j = 0; j < gamePredictions.length; j ) {
userPredictions[index] = gamePredictions[j];
index ;
}
}
return userPredictions;
}
function getPastPredictions(address user) external view returns (Prediction[] memory) {
uint256 totalPredictions = 0;
for (uint256 i = 0; i < resolvedGames.length; i ) {
totalPredictions = predictions[user][resolvedGames[i]].length;
}
uint256 index = 0;
Prediction[] memory userPredictions = new Prediction[](totalPredictions);
for (uint256 i = 0; i < resolvedGames.length; i ) {
Prediction[] memory gamePredictions = predictions[user][resolvedGames[i]];
for (uint256 j = 0; j < gamePredictions.length; j ) {
userPredictions[index] = gamePredictions[j];
index ;
}
}
return userPredictions;
}
function isPredictionCorrect(address user, uint256 gameId, uint32 predictionIdx) external view returns (bool) {
Game memory game = games[gameId];
if (!game.resolved) return false;
Prediction memory prediction = predictions[user][gameId][predictionIdx];
return prediction.result == game.result;
}
function calculateWinnings(uint256 gameId, uint256 wager, Result result) public view returns (uint256) {
Game memory game = games[gameId];
uint256 totalWager = game.homeWagerAmount game.awayWagerAmount;
uint256 winnings = (wager * totalWager) / (result == Result.Home ? game.homeWagerAmount : game.awayWagerAmount);
return winnings;
}
function readyToResolve(uint256 gameId) public view returns (bool) {
return games[gameId].timestamp GAME_RESOLVE_DELAY < block.timestamp;
}
function checkUpkeep(bytes memory) public view override returns (bool, bytes memory) {
Game[] memory activeGamesArray = getActiveGames();
for (uint256 i = 0; i < activeGamesArray.length; i ) {
uint256 gameId = getGameId(activeGamesArray[i].sportId, activeGamesArray[i].externalId);
if (readyToResolve(gameId) && pendingRequests[gameId] == 0) {
return (true, abi.encodePacked(gameId));
}
}
return (false, "");
}
function performUpkeep(bytes calldata data) external override {
uint256 gameId = abi.decode(data, (uint256));
_requestResolve(gameId);
}
function deletePendingRequest(uint256 gameId) external onlyOwner {
delete pendingRequests[gameId];
}
}
Retrieve Web2 data and store it onchain using Chainlink Functions.
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.19;
import {FunctionsClient} from "@chainlink/contracts/src/v0.8/functions/dev/v1_0_0/FunctionsClient.sol";
import {ConfirmedOwner} from "@chainlink/contracts/src/v0.8/shared/access/ConfirmedOwner.sol";
import {FunctionsRequest} from "@chainlink/contracts/src/v0.8/functions/dev/v1_0_0/libraries/FunctionsRequest.sol";
/**
* @title Chainlink Functions example consuming X (formerly Twitter) API
*/
contract XUserDataConsumer is FunctionsClient, ConfirmedOwner {
using FunctionsRequest for FunctionsRequest.Request;
enum ResponseType {
UserInfo,
UserLastTweet
}
struct APIResponse {
ResponseType responseType;
string response;
}
// Chainlink Functions script soruce code
string private constant SOURCE_USERNAME_INFO =
"const username = args[0];"
"if(!secrets.xBearerToken) {"
"throw Error('No bearer token');"
"}"
"const xUserResponse = await Functions.makeHttpRequest({"
"url: `https://api.twitter.com/2/users/by/username/${username}?user.fields=profile_image_url`,"
"headers: { Authorization: `Bearer ${secrets.xBearerToken}` },"
"});"
"if (xUserResponse.error) {"
"throw Error(`X User Request Error`);"
"}"
"const { name, id } = xUserResponse.data.data;"
"return Functions.encodeString([name, id]);";
string private constant SOURCE_LAST_TWEET_INFO =
"const id = args[0];"
"if (!secrets.xBearerToken) {"
"throw Error('No bearer token');"
"}"
"const xTweetsResponse = await Functions.makeHttpRequest({"
"url: `https://api.twitter.com/2/users/${id}/tweets`,"
"headers: { Authorization: `Bearer ${secrets.xBearerToken}` },"
"});"
"if (xTweetsResponse.error) {"
"throw Error('X User Request Error');"
"}"
"const lastTweet = xTweetsResponse.data.data[0].text;"
"const shortenedTweet = lastTweet.substring(0, 200);"
"return Functions.encodeString(shortenedTweet);";
bytes32 public donId; // DON ID for the Functions DON to which the requests are sent
uint64 private subscriptionId; // Subscription ID for the Chainlink Functions
uint32 private gasLimit; // Gas limit for the Chainlink Functions callbacks
// Mapping of request IDs to API response info
mapping(bytes32 => APIResponse) public requests;
event UserInfoRequested(bytes32 indexed requestId, string username);
event UserInfoReceived(bytes32 indexed requestId, string response);
event UserLastTweetRequested(bytes32 indexed requestId, string username);
event UserLastTweetReceived(bytes32 indexed requestId, string response);
event RequestFailed(bytes error);
constructor(
address router,
bytes32 _donId,
uint64 _subscriptionId,
uint32 _gasLimit
) FunctionsClient(router) ConfirmedOwner(msg.sender) {
donId = _donId;
subscriptionId = _subscriptionId;
gasLimit = _gasLimit;
}
/**
* @notice Request X profile information for provided handle
* @param username username of said user e.g. chainlink
* @param slotId the location of the DON-hosted secrets
* @param version the version of the secret to be used
*/
function requestUserInfo(string calldata username, uint8 slotId, uint64 version) external {
string[] memory args = new string[](1);
args[0] = username;
bytes32 requestId = _sendRequest(SOURCE_USERNAME_INFO, args, slotId, version);
requests[requestId].responseType = ResponseType.UserInfo;
emit UserInfoRequested(requestId, username);
}
/**
* @notice Request last post for given username
* @param userId username of said user e.g. chainlink
* @param slotId the location of the DON-hosted secrets
* @param version the version of the secret to be used
*/
function requestLastTweet(string calldata userId, uint8 slotId, uint64 version) external {
string[] memory args = new string[](1);
args[0] = userId;
bytes32 requestId = _sendRequest(SOURCE_LAST_TWEET_INFO, args, slotId, version);
requests[requestId].responseType = ResponseType.UserLastTweet;
emit UserLastTweetRequested(requestId, userId);
}
/**
* @notice Process the response from the executed Chainlink Functions script
* @param requestId The request ID
* @param response The response from the Chainlink Functions script
*/
function _processResponse(bytes32 requestId, bytes memory response) private {
requests[requestId].response = string(response);
if (requests[requestId].responseType == ResponseType.UserInfo) {
emit UserInfoReceived(requestId, string(response));
} else {
emit UserLastTweetReceived(requestId, string(response));
}
}
// CHAINLINK FUNCTIONS
/**
* @notice Triggers an on-demand Functions request
* @param args String arguments passed into the source code and accessible via the global variable `args`
* @param slotId the location of the DON-hosted secrets
* @param version the version of the secret to be used
*/
function _sendRequest(
string memory source,
string[] memory args,
uint8 slotId,
uint64 version
) internal returns (bytes32 requestId) {
FunctionsRequest.Request memory req;
req.initializeRequest(FunctionsRequest.Location.Inline, FunctionsRequest.CodeLanguage.JavaScript, source);
req.addDONHostedSecrets(slotId, version);
if (args.length > 0) {
req.setArgs(args);
}
requestId = _sendRequest(req.encodeCBOR(), subscriptionId, gasLimit, donId);
}
/**
* @notice Fulfillment callback function
* @param requestId The request ID, returned by sendRequest()
* @param response Aggregated response from the user code
* @param err Aggregated error from the user code or from the execution pipeline
* Either response or error parameter will be set, but never both
*/
function fulfillRequest(bytes32 requestId, bytes memory response, bytes memory err) internal override {
if (err.length > 0) {
emit RequestFailed(err);
return;
}
_processResponse(requestId, response);
}
// OWNER
/**
* @notice Set the DON ID
* @param newDonId New DON ID
*/
function setDonId(bytes32 newDonId) external onlyOwner {
donId = newDonId;
}
/**
* @notice Set the gas limit
* @param newGasLimit new gas limit
*/
function setCallbackGasLimit(uint32 newGasLimit) external onlyOwner {
gasLimit = newGasLimit;
}
}
Built using Chainlink Data Streams, this dApp enables you to use low-latency data in your smart contracts.
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.16;
import {IERC20} from "@uniswap/v2-core/contracts/interfaces/IERC20.sol";
import {ILogAutomation, Log} from "@chainlink/contracts/src/v0.8/automation/interfaces/ILogAutomation.sol";
import {StreamsLookupCompatibleInterface} from "@chainlink/contracts/src/v0.8/automation/interfaces/StreamsLookupCompatibleInterface.sol";
import {ISwapRouter} from "./interfaces/ISwapRouter.sol";
import {IVerifierProxy} from "./interfaces/IVerifierProxy.sol";
/**
* @title DataStreamsConsumer
* @dev This contract is a Chainlink Data Streams consumer.
* This contract provides low-latency delivery of low-latency delivery of market data.
* These reports can be verified onchain to verify their integrity.
*/
contract DataStreamsConsumer is
ILogAutomation,
StreamsLookupCompatibleInterface
{
// ================================================================
// | CONSTANTS |
// ================================================================
string public constant STRING_DATASTREAMS_FEEDLABEL = "feedIDs";
string public constant STRING_DATASTREAMS_QUERYLABEL = "timestamp";
uint24 public constant FEE = 3000;
// ================================================================
// | STATE |
// ================================================================
string[] public s_feedsHex;
// ================================================================
// | IMMUTABLES |
// ================================================================
address public i_linkToken;
ISwapRouter public i_router;
IVerifierProxy public i_verifier;
// ================================================================
// | STRUCTS |
// ================================================================
struct Report {
bytes32 feedId;
uint32 lowerTimestamp;
uint32 observationsTimestamp;
uint192 nativeFee;
uint192 linkFee;
uint64 upperTimestamp;
int192 benchmark;
}
struct TradeParamsStruct {
address recipient;
address tokenIn;
address tokenOut;
uint256 amountIn;
string feedId;
}
struct Quote {
address quoteAddress;
}
// ================================================================
// | Events |
// ================================================================
event InitiateTrade(
address msgSender,
address tokenIn,
address tokenOut,
uint256 amountIn,
string feedId
);
event TradeExecuted(uint256 tokensAmount);
// ================================================================
// | Errors |
// ================================================================
error InvalidFeedId(string feedId);
/**
* @dev Initializes the contract with necessary parameters.
* @param router The address of the swap router contract.
* @param verifier The address of the verifier contract.
* @param linkToken The address of the LINK token contract.
* @param feedsHex An array of hexadecimal feed IDs.
*/
function initializer(
address router,
address payable verifier,
address linkToken,
string[] memory feedsHex
) public {
i_router = ISwapRouter(router);
i_verifier = IVerifierProxy(verifier);
i_linkToken = linkToken;
s_feedsHex = feedsHex;
}
// ================================================================
// | Chainlink DON |
// ================================================================
/**
* @dev Initiates a trade by emitting a InitiateTrade event.
* When emitted Data Streams will trigger the checkLog function
* indicating that the network should initiate a trade.
* @param tokenIn The input token address.
* @param tokenOut The output token address.
* @param amount The amount to trade.
* @param feedId data feed of the id you are trading
*/
function trade(
address tokenIn,
address tokenOut,
uint256 amount,
string memory feedId
) external {
emit InitiateTrade(msg.sender, tokenIn, tokenOut, amount, feedId);
}
/**
* @dev Checks the log data using Chainlink Data Streams via the StreamsLookup error.
* Once StreamsLookUp error is emitted the data in the error is passed
* to the checkCallback function. Which afterwards executes performUpkeep.
* @param log The log data to be checked.
* @return A boolean indicating if performUpkeep is needed.
*/
function checkLog(
Log calldata log,
bytes memory
) external view returns (bool, bytes memory) {
revert StreamsLookup(
STRING_DATASTREAMS_FEEDLABEL,
s_feedsHex,
STRING_DATASTREAMS_QUERYLABEL,
log.timestamp,
log.data
);
}
/**
* @dev Checks if upkeep is needed and returns the corresponding performData.
* @param values An array of values for the upkeep check.
* @param extraData Additional data for the upkeep.
* @return upkeepNeeded A boolean indicating whether upkeep is needed
* @return performData Bytes that include the signed reports and the extra data
* that is passed in StreamsLookup error.
*/
function checkCallback(
bytes[] memory values,
bytes memory extraData
) external pure returns (bool upkeepNeeded, bytes memory performData) {
return (true, abi.encode(values, extraData));
}
/**
* @dev 1. Decodes the report and extraData.
* 2. Verifies the integrity of the data.
* 3. Performs a swap between tokens using the verified report data.
* This function is executed by Chainlink's Automation Registry.
* @notice This contract needs to have the networks native token to verify the report.
* @param performData The data needed to perform the upkeep.
*/
function performUpkeep(bytes calldata performData) external {
(
Report memory unverifiedReport,
TradeParamsStruct memory tradeParams,
bytes memory bundledReport
) = _decodeData(performData);
// verify tokens
bytes memory verifiedReportData = i_verifier.verify{
value: unverifiedReport.nativeFee
}(bundledReport, abi.encode(i_linkToken));
Report memory verifiedReport = abi.decode(verifiedReportData, (Report));
// swap tokens
uint256 successfullyTradedTokens = _swapTokens(
verifiedReport,
tradeParams
);
emit TradeExecuted(successfullyTradedTokens);
}
// ================================================================
// | REPORT MANIPULATION |
// ================================================================
/**
* @dev Decodes and extracts relevant data from the provided `performData`.
* It decodes the `performData` into signed reports, swap parameters,
* and a bundled report.
* @param performData The data needed for the decoding process.
* @return signedReport The decoded report from the bundled report data.
* @return tradeParams The decoded swap parameters.
* @return bundledReport The bundled report data for verification.
*/
function _decodeData(
bytes memory performData
)
private
view
returns (
Report memory signedReport,
TradeParamsStruct memory tradeParams,
bytes memory bundledReport
)
{
(bytes[] memory signedReports, bytes memory extraData) = abi.decode(
performData,
(bytes[], bytes)
);
(
address sender,
address tokenIn,
address tokenOut,
uint256 amountIn,
string memory feedId
) = abi.decode(extraData, (address, address, address, uint256, string));
tradeParams = TradeParamsStruct({
recipient: sender,
tokenIn: tokenIn,
tokenOut: tokenOut,
amountIn: amountIn,
feedId: feedId
});
uint256 feedIdIndex = getIdFromFeed(feedId);
bundledReport = _bundleReport(signedReports[feedIdIndex]);
signedReport = _getReportData(bundledReport);
}
/**
* @dev Bundles a report with a quote and returns the bundled report.
* @param report The report to be bundled.
* @return The bundled report.
*/
function _bundleReport(
bytes memory report
) private view returns (bytes memory) {
Quote memory quote;
quote.quoteAddress = i_linkToken;
(
bytes32[3] memory reportContext,
bytes memory reportData,
bytes32[] memory rs,
bytes32[] memory ss,
bytes32 raw
) = abi.decode(
report,
(bytes32[3], bytes, bytes32[], bytes32[], bytes32)
);
bytes memory bundledReport = abi.encode(
reportContext,
reportData,
rs,
ss,
raw,
abi.encode(quote)
);
return bundledReport;
}
/**
* @dev Extracts and decodes the report data from a signed report.
* @param signedReport The signed report.
* @return The decoded report data.
*/
function _getReportData(
bytes memory signedReport
) internal pure returns (Report memory) {
(, bytes memory reportData, , , ) = abi.decode(
signedReport,
(bytes32[3], bytes, bytes32[], bytes32[], bytes32)
);
Report memory report = abi.decode(reportData, (Report));
return report;
}
/**
* @dev Returns the index of a feed ID in the array of feed IDs.
* @param feedId The feed id that you are looking for its index
* @return The index of the feed ID in the array, or reverts with an error if not found.
*/
function getIdFromFeed(string memory feedId) public view returns (uint256) {
uint256 result;
string[] storage feeds = s_feedsHex;
for (uint256 i = 0; i < feeds.length; i ) {
if (
keccak256(abi.encode(feeds[i])) == keccak256(abi.encode(feedId))
) {
result = i;
break;
}
if (i == feeds.length - 1) {
revert InvalidFeedId(feedId);
}
}
return result;
}
// ================================================================
// | SWAP |
// ================================================================
/**
* @dev Scales the price from a report to match the token's decimals.
* @param tokenOut The output token for which the price should be scaled.
* @param priceFromReport The price from the report to be scaled.
* @return The scaled price with the appropriate token decimals.
*/
function _scalePriceToTokenDecimals(
IERC20 tokenOut,
int192 priceFromReport
) private view returns (uint256) {
uint256 pricefeedDecimals = 18;
uint8 tokenOutDecimals = tokenOut.decimals();
if (tokenOutDecimals < pricefeedDecimals) {
uint256 difference = pricefeedDecimals - tokenOutDecimals;
return uint256(uint192(priceFromReport)) / 10 ** difference;
} else {
uint256 difference = tokenOutDecimals - pricefeedDecimals;
return uint256(uint192(priceFromReport)) * 10 ** difference;
}
}
/**
* @dev Swaps tokens using the verified report data and swap parameters.
* It first decodes the verified report data to obtain the benchmark price,
* then transfers tokens from the recipient to this contract, approves the
* token transfer, and executes the swap using the provided parameters.
* @param verifiedReport The verified report data containing price information.
* @param tradeParams The parameters for the token swap.
* @return The amount of tokens received after the swap.
*/
function _swapTokens(
Report memory verifiedReport,
TradeParamsStruct memory tradeParams
) private returns (uint256) {
uint8 inputTokenDecimals = IERC20(tradeParams.tokenIn).decimals();
uint256 priceForOneToken = _scalePriceToTokenDecimals(
IERC20(tradeParams.tokenOut),
verifiedReport.benchmark
);
uint256 outputAmount = (priceForOneToken * tradeParams.amountIn) /
10 ** inputTokenDecimals;
IERC20(tradeParams.tokenIn).transferFrom(
tradeParams.recipient,
address(this),
tradeParams.amountIn
);
IERC20(tradeParams.tokenIn).approve(
address(i_router),
tradeParams.amountIn
);
ISwapRouter.ExactInputSingleParams memory params = ISwapRouter
.ExactInputSingleParams(
tradeParams.tokenIn,
tradeParams.tokenOut,
FEE,
tradeParams.recipient,
tradeParams.amountIn,
outputAmount,
0
);
return i_router.exactInputSingle(params);
}
/**
* @dev Extracts and decodes the report data from a signed report.
* This function is needed because the contract needs native tokens
* to verify reports.
**/
receive() external payable {}
}
Create batch-revealed NFT collections powered by Chainlink Automation & VRF.
// SPDX-License-Identifier: MIT
pragma solidity 0.8.4;
import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/token/ERC721/extensions/ERC721Enumerable.sol";
import "@openzeppelin/contracts/utils/Strings.sol";
import "@openzeppelin/contracts/utils/Base64.sol";
import "@chainlink/contracts/src/v0.8/VRFConsumerBaseV2.sol";
import "@chainlink/contracts/src/v0.8/interfaces/VRFCoordinatorV2Interface.sol";
import "@chainlink/contracts/src/v0.8/KeeperCompatible.sol";
import "./INFTCollection.sol";
contract NFTCollection is
INFTCollection,
Ownable,
ERC721Enumerable,
VRFConsumerBaseV2,
KeeperCompatibleInterface
{
// STRUCTS
struct Metadata {
uint256 startIndex;
uint256 endIndex;
uint256 entropy;
}
// IMMUTABLE STORAGE
uint256 private immutable MAX_SUPPLY;
uint256 private immutable MINT_COST;
// MUTABLE STORAGE
uint256 private s_revealedCount;
uint256 private s_revealBatchSize;
uint256 private s_revealInterval;
uint256 private s_lastRevealed = block.timestamp;
bool private s_revealInProgress;
Metadata[] private s_metadatas;
// VRF CONSTANTS & IMMUTABLE
uint16 private constant VRF_REQUEST_CONFIRMATIONS = 3;
uint32 private constant VRF_NUM_WORDS = 1;
VRFCoordinatorV2Interface private immutable VRF_COORDINATOR_V2;
uint64 private immutable VRF_SUBSCRIPTION_ID;
bytes32 private immutable VRF_GAS_LANE;
uint32 private immutable VRF_CALLBACK_GAS_LIMIT;
// EVENTS
event BatchRevealRequested(uint256 requestId);
event BatchRevealFinished(uint256 startIndex, uint256 endIndex);
// ERRORS
error InvalidAmount();
error MaxSupplyReached();
error InsufficientFunds();
error RevealCriteriaNotMet();
error RevealInProgress();
error InsufficientLINK();
error WithdrawProceedsFailed();
error NonExistentToken();
constructor(
string memory _name,
string memory _symbol,
uint256 _maxSupply,
uint256 _mintCost,
uint256 _revealBatchSize,
uint256 _revealInterval,
address _vrfCoordinatorV2,
uint64 _vrfSubscriptionId,
bytes32 _vrfGasLane,
uint32 _vrfCallbackGasLimit
) ERC721(_name, _symbol) VRFConsumerBaseV2(_vrfCoordinatorV2) {
MAX_SUPPLY = _maxSupply;
MINT_COST = _mintCost;
VRF_COORDINATOR_V2 = VRFCoordinatorV2Interface(_vrfCoordinatorV2);
VRF_SUBSCRIPTION_ID = _vrfSubscriptionId;
VRF_GAS_LANE = _vrfGasLane;
VRF_CALLBACK_GAS_LIMIT = _vrfCallbackGasLimit;
s_revealBatchSize = _revealBatchSize;
s_revealInterval = _revealInterval;
}
// ACTIONS
function mint(uint256 _amount) external payable override {
uint256 totalSupply = totalSupply();
if (_amount == 0) {
revert InvalidAmount();
}
if (totalSupply _amount > MAX_SUPPLY) {
revert MaxSupplyReached();
}
if (msg.value < MINT_COST * _amount) {
revert InsufficientFunds();
}
for (uint256 i = 1; i <= _amount; i ) {
_safeMint(msg.sender, totalSupply i);
}
}
function withdrawProceeds() external override onlyOwner {
(bool sent, ) = payable(owner()).call{value: address(this).balance}("");
if (!sent) {
revert WithdrawProceedsFailed();
}
}
// GETTERS
function tokenURI(uint256 tokenId)
public
view
override
returns (string memory)
{
if (!_exists(tokenId)) {
revert NonExistentToken();
}
(uint256 randomness, bool metadataCleared) = _getTokenRandomness(tokenId);
string memory svg = _generateSVG(randomness, metadataCleared);
string memory svgEncoded = _svgToImageURI(svg);
return _formatTokenURI(svgEncoded);
}
function revealedCount() external view override returns (uint256) {
return s_revealedCount;
}
function lastRevealed() external view override returns (uint256) {
return s_lastRevealed;
}
function batchSize() external view override returns (uint256) {
return s_revealBatchSize;
}
function revealInterval() external view override returns (uint256) {
return s_revealInterval;
}
function batchCount() external view returns (uint256) {
return s_metadatas.length;
}
function batchDetails(uint256 index)
external
view
returns (
uint256,
uint256,
uint256
)
{
Metadata memory batch = s_metadatas[index];
return (batch.startIndex, batch.endIndex, batch.entropy);
}
function mintCost() public view override returns (uint256) {
return MINT_COST;
}
function maxSupply() external view override returns (uint256) {
return MAX_SUPPLY;
}
// HELPERS
function _getTokenRandomness(uint256 tokenId)
internal
view
returns (uint256 randomness, bool metadataCleared)
{
for (uint256 i = 0; i < s_metadatas.length; i ) {
if (
tokenId >= s_metadatas[i].startIndex &&
tokenId < s_metadatas[i].endIndex
) {
randomness = uint256(
keccak256(abi.encode(s_metadatas[i].entropy, tokenId))
);
metadataCleared = true;
}
}
}
function _formatTokenURI(string memory imageURI)
internal
pure
returns (string memory)
{
return
string(
abi.encodePacked(
"data:application/json;base64,",
Base64.encode(
bytes(
abi.encodePacked(
'{',
'"name":"NFT", ',
'"description":"Batch-revealed NFT!", ',
'"attributes":"", ',
'"image":"', imageURI, '"',
'}'
)
)
)
)
);
}
function _generateSVG(uint256 _randomness, bool _metadataCleared)
internal
pure
returns (string memory)
{
string[4] memory parts;
parts[0] = '<svg xmlns="http://www.w3.org/2000/svg" preserveAspectRatio="xMinYMin meet" viewBox="0 0 350 350">';
if (_metadataCleared) {
parts[1] = '<style>.base { fill: white; font-family: serif; font-size: 59px; }</style><rect width="100%" height="100%" fill="black" /><text class="base">';
string[6] memory svgRows;
string memory randomnessString = Strings.toHexString(_randomness, 32);
for (uint8 i = 0; i < 6; i ) {
string memory partialString = _substring(randomnessString, i * 11, (i 1) * 11);
svgRows[i] = string(
abi.encodePacked(
'<tspan x="16" dy="56">',
partialString,
"</tspan>"
)
);
}
parts[2] = string(
abi.encodePacked(
svgRows[0],
svgRows[1],
svgRows[2],
svgRows[3],
svgRows[4],
svgRows[5]
)
);
} else {
parts[1] = '<style>.base { fill: white; font-family: serif; font-size: 350px; }</style><rect width="100%" height="100%" fill="black" /><text x="90" y="295" class="base">';
parts[2] = "?";
}
parts[3] = "</text></svg>";
return string(abi.encodePacked(parts[0], parts[1], parts[2], parts[3]));
}
function _svgToImageURI(string memory svg)
internal
pure
returns (string memory)
{
string memory baseURL = "data:image/svg xml;base64,";
string memory svgBase64Encoded = Base64.encode(bytes(string(abi.encodePacked(svg))));
return string(abi.encodePacked(baseURL, svgBase64Encoded));
}
function _substring(
string memory str,
uint256 startIndex,
uint256 endIndex
) internal pure returns (string memory) {
bytes memory strBytes = bytes(str);
bytes memory result = new bytes(endIndex - startIndex);
for (uint256 i = startIndex; i < endIndex; i ) {
result[i - startIndex] = strBytes[i];
}
return string(result);
}
// REVEAL
function shouldReveal() public view override returns (bool) {
uint256 unrevealedCount = totalSupply() - s_revealedCount;
if (unrevealedCount == 0) {
return false;
}
bool batchSizeCriteria = false;
if (s_revealBatchSize > 0 && unrevealedCount >= s_revealBatchSize) {
batchSizeCriteria = true;
}
bool intervalCriteria = false;
if (
s_revealInterval > 0 &&
block.timestamp - s_lastRevealed > s_revealInterval
) {
intervalCriteria = true;
}
return (batchSizeCriteria || intervalCriteria);
}
function revealPendingMetadata()
public
override
returns (uint256 requestId){
if (s_revealInProgress) {
revert RevealInProgress();
}
if (!shouldReveal()) {
revert RevealCriteriaNotMet();
}
requestId = VRF_COORDINATOR_V2.requestRandomWords(
VRF_GAS_LANE,
VRF_SUBSCRIPTION_ID,
VRF_REQUEST_CONFIRMATIONS,
VRF_CALLBACK_GAS_LIMIT,
VRF_NUM_WORDS
);
s_revealInProgress = true;
emit BatchRevealRequested(requestId);
}
function _fulfillRandomnessForMetadata(uint256 randomness) internal {
uint256 totalSupply = totalSupply();
uint256 startIndex = s_revealedCount 1;
uint256 endIndex = totalSupply 1;
s_metadatas.push(
Metadata({
startIndex: startIndex,
endIndex: endIndex,
entropy: randomness
})
);
s_revealedCount = totalSupply;
s_lastRevealed = block.timestamp;
s_revealInProgress = false;
emit BatchRevealFinished(startIndex, endIndex);
}
// VRF
function fulfillRandomWords(uint256, uint256[] memory randomWords)
internal
override
{
_fulfillRandomnessForMetadata(randomWords[0]);
}
// KEEPERS
function checkUpkeep(bytes calldata)
external
view
override
returns (bool upkeepNeeded, bytes memory)
{
upkeepNeeded = !s_revealInProgress && shouldReveal();
}
function performUpkeep(bytes calldata) external override {
revealPendingMetadata();
}
// SETTERS
function setRevealBatchSize(uint256 _revealBatchSize)
external
override
onlyOwner
{
s_revealBatchSize = _revealBatchSize;
}
function setRevealInterval(uint256 _revealInterval)
external
override
onlyOwner
{
s_revealInterval = _revealInterval;
}
function supportsInterface(bytes4 interfaceId)
public
view
override
returns (bool)
{
return
super.supportsInterface(interfaceId) ||
interfaceId == type(INFTCollection).interfaceId;
}
}
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