Error in creating uniswap pair for smart contract - solidity

I am getting the below error on calling function setRouterAddress with router address 0xD99D1c33F9fC3444f8101754aBC46c52416550D1 in testnet.
Gas estimation failed error
Gas estimation errored with the following message (see below). The transaction execution will likely fail. Do you want to force sending?
execution reverted
this is message is coming for this line of code in the below function. IUniswapV2Factory(_uniswapV2Router.factory()).createPair(address(this), _uniswapV2Router.WETH());
declarations:
IUniswapV2Router02 public unswapV2Router;
address public unswapV2Pair;
Function:
function setRouterAddress(address newRouter) external onlyOwner() returns(address, address){
IUniswapV2Router02 _uniswapV2Router = IUniswapV2Router02(newRouter);
// Create a uniswap pair for this new token
uniswapV2Pair = IUniswapV2Factory(_uniswapV2Router.factory()).createPair(address(this), _uniswapV2Router.WETH());
// set the rest of the contract variables
uniswapV2Router = _uniswapV2Router;
return (newRouter, uniswapV2Pair);
}
Could someone guide what is the problem ?

Related

Burning Deployed ERC Tokens In an NFT Mint Function - Compiles, but Transaction Fails

I am very new to Solidity, and have recently been working on trying to learn the ropes. For reference, I have been using code from this video (https://www.youtube.com/watch?v=tBMk1iZa85Y) as a primer after having gone through the basic crypto zombies tutorial series.
I have been attempting to adapt the Solidity contract code presented in this video (which I had functioning just fine!) to require a Burn of a specified amount of an ERC-20 token before minting an NFT as an exercise for myself. I thought I had what should be a valid implementation which compiled in Remix, and then deployed to Rinkeby. I call the allowAccess function in Remix after deploying to Rinkeby, and that succeeds. But, when I call the mint function with the two parameters, I get: "gas estimation errored with the following message (see below). The transaction execution will likely fail. Do you want to force sending? execution reverted."
If I still send the transaction, metamask yields "Transaction xx failed! Transaction encountered an error.".
I'm positive it has to do with "require(paymentToken.transfer(burnwallet, amounttopay),"transfer Failed");", though I'm not sure what's wrong. Below is my entire contract code. I'm currently just interacting with the Chainlink contract on Rinkeby as my example, since they have a convenient token faucet.
pragma solidity ^0.8.0;
import "https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/token/ERC721/ERC721.sol";
import "https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/token/ERC20/IERC20.sol";
import "https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/access/Ownable.sol";
import "https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/utils/Counters.sol";
contract myNFTwithBurn is ERC721, Ownable {
address externalTokenAddress = 0x01BE23585060835E02B77ef475b0Cc51aA1e0709; //Token Type to burn on minting
uint256 amounttopay = 5; //number of these tokens to burn
IERC20 paymentToken = IERC20(externalTokenAddress); //my code: create an interface of the external token
address burnwallet = 0x000000000000000000000000000000000000dEaD; //burn wallet
using Counters for Counters.Counter;
Counters.Counter private _tokenIds;
using Strings for uint256;
// Optional mapping for token URIs
mapping (uint256 => string) private _tokenURIs;
// Base URI
string private _baseURIextended;
constructor() ERC721("NFTsWithBurn","NWB") {
}
function setBaseURI(string memory baseURI_) external onlyOwner() {
_baseURIextended = baseURI_;
}
function _setTokenURI(uint256 tokenId, string memory _tokenURI) internal virtual {
require(_exists(tokenId), "ERC721Metadata: URI set of nonexistent token");
_tokenURIs[tokenId] = _tokenURI;
}
function _baseURI() internal view virtual override returns (string memory) {
return _baseURIextended;
}
function tokenURI(uint256 tokenId) public view virtual override returns (string memory) {
require(_exists(tokenId), "ERC721Metadata: URI query for nonexistent token");
string memory _tokenURI = _tokenURIs[tokenId];
string memory base = _baseURI();
// If there is no base URI, return the token URI.
if (bytes(base).length == 0) {
return _tokenURI;
}
// If both are set, concatenate the baseURI and tokenURI (via abi.encodePacked).
if (bytes(_tokenURI).length > 0) {
return string(abi.encodePacked(base, _tokenURI));
}
// If there is a baseURI but no tokenURI, concatenate the tokenID to the baseURI.
return string(abi.encodePacked(base, tokenId.toString()));
}
function allowAccess() public
{
paymentToken.approve(address(this), 5000000); //This is my attempt to allow the contract access to the user's external tokens, in this case Chainlink (paymentToken)
}
function mintItem(address to, string memory tokenURI)
public
onlyOwner
returns (uint256)
{
require(paymentToken.transfer(burnwallet, amounttopay),"transfer Failed"); //Try to transfer 5 chainlink to the burn wallet
_tokenIds.increment();
uint256 id = _tokenIds.current();
_mint(to, id);
_setTokenURI(id, tokenURI);
return id;
}
}
If anybody can at least point me to what I'm doing completely wrong in the code that I've added, please do! TIA!
I'm not sure why are you trying to burn link in order to mint and nft but first check if the link code does not have a require that check if the destination address is the burn address if it has then burn the link is not possible and you should use any other erc20 maybe your own erc20, also your contract probably does not have any link and if you want to transfer the link from the user you should do this in the contract paymentToken.transferFrom(msg.sender,destinationAddress,amount) and if the user previously approve your contract you will able to send the tokens, and i suppose that the purpose of the allowAccess function is to make the user approve the contract to move the tokens that will never work, the approve function let's anyone that call it approve any address to move an amount of tokens, the thing is that to know who is approving to let other to move the tokens the function use msg.sender to explain how this work take a look at this example
let's say that your contract is the contract A and the link contract is the contract B
now a user call allowAccess in the contract A, so here the msg.sender is the user because they call the function
now internally this function call approve on contract B, here the contract A is the msg.sender, because the contract is who call the function
so what allowAccess is really doing is making the contract approving itself to move their own tokens that I assume it doesn't have

Warning! Error encountered during contract execution [execution reverted]

I am just learning about solidity, I got this code and when I deploy it I got this error can you help me how to fix it?
I don't know where the error exists.
I am using BSC Test-net
constructor () {
_rOwned[_msgSender()] = _rTotal; // assigning the max reflection token to owner's address
ISummitSwapRouter01 _summitSwapRouter = ISummitSwapRouter01(0x10ED43C718714eb63d5aA57B78B54704E256024E);
// Create a summitswap pair for this new token
summitSwapPair = ISummitSwapFactory(_summitSwapRouter.factory())
.createPair(address(this), _summitSwapRouter.WETH());
//exclude owner and this contract from fee
_isExcludedFromFee[owner()] = true;
_isExcludedFromFee[address(this)] = true;
_isExcludedFromFee[_CodradoLiquidityProviderAddress] = true;
//Exclude dead address from reflection
_isExcludedFromReflection[address(0)] = true;
_isExcludedFromReflection[0x000000000000000000000000000000000000dEaD] = true;
emit Transfer(address(0), _msgSender(), _tTotal);
}
There's no contract on the 0x10ED... address on the BSC testnet.
When your code is calling the .factory() function, it expects a response. But no response comes from the non-contract address, which causes the revert.

The called function should be payable error in withdraw function

I have such function to transfer tokens from contract and i get error where shoudl i add payable and i dont really understand if withdraw will withdraw ethers or tokens?
function withdrawBalances() public nonReentrant {
uint share = _Balances[msg.sender];
_Balances[msg.sender] = 0;
msg.sender.transfer(share);
}
.withdrawBalances errored: VM error: revert. revert The transaction has been reverted to the initial state. Note: The called function should be payable if you send value and the value you send should be less than your current balance. Debug the transaction to get more information.
This error occurs when you try to send some Ether when calling a function that isn't payable. Set Ether value to 0 to avoid this. You can also allow a function to accept Ether by using the payable keyword.
function withdrawBalances() public payable {
...
}

“Out of Gas” while transferring ethereum from account to contract

I am using ganache to create 10 ethereum accounts. I want to transfer ethereum from one account to a smart contract. I am doing this by writing two following smart contracts in solidity;
pragma solidity >=0.4.0 <0.6.0;
contract Ether_Transfer_To{
function () external payable { //fallback function
}
function get_balance() public returns(uint){
return address(this).balance;
}
}
contract Ether_Transfer_From{
Ether_Transfer_To private the_instance;
constructor() public{
//the_instance=Ether_Transfer_To(address(this));
the_instance=new Ether_Transfer_To();
}
function get_balance() public returns(uint){
return address(this).balance;
}
function get_balance_of_instance() public returns(uint){
//return address(the_instance).balance;
return the_instance.get_balance();
}
function () external payable {
// msg.sender.send(msg.value)
address(the_instance).send(msg.value);
}
}
When I deploy the contract Ether_Transfer_From smart contract then I get its three-member functions as follows in remix;
But when I sent one 1 Wei from account to smart contract by writing 1 in the text box and clicking on a (fallback) button, then I get the following error;
transact to Ether_Transfer_From. (fallback) errored: VM Exception while
processing transaction: out of gas
I followed the answer of the same question by installing Ganache-cli 7.0.0 beta.0 by using following command;
npm install -g ganache-cli#7.0.0-beta.0
But I still get the same error. I think I am using older Ganache cli instead of Ganache-cli 7.0.0 beta.0 as it goes to C drive and I installed ganache 2.1.1 in D drive previously.
I just want to send ethereum from one account to other but I am really stuck in this out of gas Error. If there is any way to remove this error or transfer ethereum from one account to another then please let me know.
So this is what I did for one of my projects.
This snippet, deploys the compiles the solidity file and then deploys it and gets the address of the deployed contract address
const input = fs.readFileSync('Migrations.sol');
const output = solc.compile(input.toString(), 1);
const bytecode = output.contracts[':Migrations']['bytecode'];
const abi = JSON.parse(output.contracts[':Migrations'].interface);
var contract = new web3.eth.Contract(abi);
contract.deploy({
data: '0x'+bytecode,
})
.send({
from: chairPerson,
gas: 5500000,
gasPrice: '2000000000000'
})
.on('receipt', (receipt) => {
add=receipt.contractAddress;
})
Now using contract's abi, I can call methods of the deployed contract and use the following code to transfer '1.5' ether from one address to another.
contract.methods.registerRequest(fromAddress,toAddress,requestNumber).send({from:fromAddress,value : web3.utils.toWei('1.5', 'ether')}).on('transactionHash', (hashResult) => {-- some code--})
And also make the method in the solidity as payable to allow it to transfer ether, like :
function registerRequest(address requestedBy,address requestedTo,uint requestNumber) payable public{}
Refer : https://web3js.readthedocs.io/en/v1.2.0/web3-eth-contract.html#id12
Basically I used web3 api itself to transfer ether from one account
to another by calling my solidity method.
Also, check the following things :
1. While deploying, are you deploying with enough gas ? I faced this error when I was deploying the contract with less gas quantity
2. Your method in solidity should be payable

Even-though i don't have constructor in my code i am getting error the constructor should be payable if you send value

This is my code in Solidity
pragma solidity ^0.4.17;
contract WithdrawalContract {
mapping(address => uint) buyers;
function buy()public payable {
require(msg.value > 0);
buyers[msg.sender] = msg.value;
}
function withdraw()public {
uint amount = buyers[msg.sender];
require(amount > 0);
buyers[msg.sender] = 0;
require(msg.sender.send(amount));
}
}
Below is the error i am getting. Not sure why it is asking for constructor
transact to WithdrawalContract.buy errored: VM error: revert.
revert The transaction has been reverted to the initial state.
Note: The constructor should be payable if you send value. Debug the transaction to get more information.
That's just part of the error message Remix shows when a transaction reverts, presumably because that's a common mistake people make.
In your case, that's not the issue. My guess would be that you're calling buy and not attaching any ether, so the require(msg.value > 0) is causing the transaction to revert. In Remix, make sure you have a non-zero "value" in the upper right.