Interfaces. Why am I getting a type error when trying to use an external function? - interface

Question

Here is the code for my main smart contract.
Errors on the last two functions.
from solidity: TypeError: Invalid type for argument in function call.
Invalid implicit conversion from type(uint256) to uint256 requested.
--> contracts/DIV4.sol:39:57: | 39 | randomness_interface(_random).fulfillRandomness(uint256); |
^^^^^^
from solidity: TypeError: Invalid type for argument in function call.
Invalid implicit conversion from type(bytes32) to bytes32 requested.
--> contracts/DIV4.sol:43:55: | 43 | randomness_interface(_random).getRandomNumber(bytes32); |
^^^^^^^
import "https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/token/ERC1155/ERC1155.sol";
import {randomness_interface} from "./randomness_interface.sol";
contract Divergence is ERC1155, Ownable {
uint256 public constant One = 0;
uint256 public constant Two = 1;
uint256 public constant Three = 2;
uint256 public constant Four = 3;
constructor() ERC1155 ("https://ipfs.io/ipfs/dsfgijdsfklj348rue0ur099045948.json"){
_mint(msg.sender, item1, 1000, "" );
_mint(msg.sender, item2, 130, "" );
_mint(msg.sender, item3, 65, "" );
_mint(msg.sender, item4, 3, "" );
}
function uri(uint256 _tokenId) override public view returns (string memory) {
return string(
abi.encodePacked(
"https://ipfs.io/ipfs/Qmf4WrTGA2fYJXitigvqJ7FDVMPreJQW4of8HZ1k5Wzkd3?filename=Divergence1",
Strings.toString(_tokenId),
".json"
)
);
}
function generateRandomNumber(address _random) external(bytes32 requestId) {
randomness_interface(_random).fulfillRandomness(uint256);
}
function getRandomNumberfromOutside(address _random) external {
randomness_interface(_random).getRandomNumber(bytes32);
}
Interface.sol file.
pragma solidity ^0.8.0;
interface randomness_interface {
function fulfillRandomness(uint256 randomness) external view returns (uint);
function getRandomNumber(bytes32 requestId) external;
}
Finally, the file with all the randomization happening.
pragma solidity ^0.6.6;
import "https://github.com/smartcontractkit/chainlink/blob/develop/contracts/src/v0.8/VRFConsumerBase.sol";
contract RandomNumber is VRFConsumerBase {
bytes32 public keyHash;
uint256 public fee;
uint256 public randomResult;
constructor() VRFConsumerBase(0xdD3782915140c8f3b190B5D67eAc6dc5760C46E9, 0xa36085F69e2889c224210F603D836748e7dC0088) public {
keyHash = 0x6c3699283bda56ad74f6b855546325b68d482e983852a7a82979cc4807b641f4;
fee = 0.1 * 10 ** 18; //0.1 LINK
}
function getRandomNumber() public returns (bytes32 requestId) {
return requestRandomness(keyHash, fee);
}
function fulfillRandomness(bytes32 requestId, uint256 randomness) internal override {
randomResult = randomness.mod(100).add(1);
}
}

Answer 1

You are not passing correct arguments to the functions.
-
function generateRandomNumber(address _random) external(bytes32 requestId) {
randomness_interface(_random).fulfillRandomness(uint256);
}
You are calling randomness_interface(_random).fulfillRandomness and fulfillRandomness expects
function fulfillRandomness(bytes32 requestId, uint256 randomness)
I am not sure if this is the correct way of calling fulfillRandomness
function generateRandomNumber(address _random) external(bytes32 requestId) {
randomness_interface(_random).fulfillRandomness(uint256);
}
Because as far as I know, fulfillRandomness gets called by the chainlink node, so you make request, get the random number and then chainlink will call fulfillRandomness. I think you should have written like this:
function fulfillRandomness(bytes32 requestId,uint256 randomNumber) internal override{
}