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@PatrickAlphaC
Forked from alexroan/RandomNumberConsumer.sol
Last active June 23, 2021 12:12
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Random Number Generator. Use this gist as a way to generate a random number in solidity or your EVM compatible smart contracts. If you'd like to deploy it to remix, try this: url: https://remix.ethereum.org/#version=soljson-v0.6.6+commit.6c089d02.js&optimize=false&evmVersion=null&gist=f47e4eae5f2ffa7868ef4ecd5bda9044
/** 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 0.6.6;
import "@chainlink/contracts/src/v0.6/VRFConsumerBase.sol";
contract RandomNumberConsumer is VRFConsumerBase {
bytes32 internal keyHash;
uint256 internal fee;
uint256 public randomResult;
/**
* Constructor inherits VRFConsumerBase
*
* Network: Kovan
* Chainlink VRF Coordinator address: 0xdD3782915140c8f3b190B5D67eAc6dc5760C46E9
* LINK token address: 0xa36085F69e2889c224210F603D836748e7dC0088
* Key Hash: 0x6c3699283bda56ad74f6b855546325b68d482e983852a7a82979cc4807b641f4
*/
constructor()
VRFConsumerBase(
0xdD3782915140c8f3b190B5D67eAc6dc5760C46E9, // VRF Coordinator
0xa36085F69e2889c224210F603D836748e7dC0088 // LINK Token
) public
{
keyHash = 0x6c3699283bda56ad74f6b855546325b68d482e983852a7a82979cc4807b641f4;
fee = 0.1 * 10 ** 18; // 0.1 LINK
}
/**
* Requests randomness
*/
function getRandomNumber() public returns (bytes32 requestId) {
require(LINK.balanceOf(address(this)) > fee, "Not enough LINK - fill contract with faucet");
return requestRandomness(keyHash, fee);
}
/**
* Callback function used by VRF Coordinator
*/
function fulfillRandomness(bytes32 requestId, uint256 randomness) internal override {
randomResult = randomness;
}
/**
* Withdraw LINK from this contract
*
* DO NOT USE THIS IN PRODUCTION AS IT CAN BE CALLED BY ANY ADDRESS.
* THIS IS PURELY FOR EXAMPLE PURPOSES.
*/
function withdrawLink() external {
require(LINK.transfer(msg.sender, LINK.balanceOf(address(this))), "Unable to transfer");
}
}
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