I am trying my hands on a program which transfers test ethers from one account to other on remix ide using javascript VM environment. I am unable to see funds getting transferred to beneficiary account.
I have put diagnostic code as well which prints the contract current balance but it always prints 0.
pragma solidity <=0.5.7;
contract MultiSigWallet{
address payable private owner;
address payable private beneficiary;
uint private minApprovers ;
uint private currentApprovals;
mapping(address => bool) approvedBy;
mapping(address =>bool) isApprover;
uint public contractBalance;
constructor (address payable _beneficiary, address [] memory _approvers, int32 _minApprovers) public payable{
require(_approvers.length > 0 && _minApprovers > 0,"At least one approver is required!");
require(_approvers.length >= minApprovers,"Number of minimum approvers cannot be more than total approvers count");
owner = msg.sender;
beneficiary = _beneficiary;
for(uint i = 0;i<_approvers.length;i++){
isApprover[_approvers[i]]= true;
}
}
function approve () public{
require(isApprover[msg.sender],"Not an Approver");
if(!approvedBy[msg.sender]){
approvedBy[msg.sender] = true;
currentApprovals++;
}
if(currentApprovals== minApprovers){
beneficiary.send(address(this).balance);
selfdestruct(owner);
}
}
function getContractBalance () public payable returns( uint){
contractBalance = address(this).balance;
}
function reject() public {
require(isApprover[msg.sender],"Not an approver!");
selfdestruct(owner);
}
}
if i provide beneficiary address as a1, list of approvers as a2,a3 and i invoke the constructor with a4 by putting 10 ethers in the value field, i can see 10 ether reduction in a4 balance.
Next after approving from accounts a2, a3, i am expecting the balance of a1 to swell by 10 ethers and balance of contract turns 0.
However i don't see a change in a1 balance and contract balance is always 0.
Can someone explain what i am doing wrong or if any gaps in my understanding?
You probably want to do something like minApprovers = _minApprovers in the constructor. Otherwise minApprovers is always 0, and your == check will always fail because the first successful call to approve will make currentApprovals == 1.
Related
I've seen some problems with calling functions from other contracts but I believe my problem is fairly genuine to demand a separate question if only to be negated in its possibility.
So I am trying to call a contract within another contract. Is it possible to get the blockhash of a particular block number of the callee contract within my caller? If so how?
Every syntax I've attempted fails for some reason.
Contract A
enter code here
contract DiceGame {
uint256 public nonce = 0;
uint256 public prize = 0;
event Roll(address indexed player, uint256 roll);
event Winner(address winner, uint256 amount);
constructor() payable {
resetPrize();
}
function resetPrize() private {
prize = ((address(this).balance * 10) / 100);
}
function rollTheDice() public payable {
require(msg.value >= 0.002 ether, "Failed to send enough value");
bytes32 prevHash = blockhash(block.number - 1);
bytes32 hash = keccak256(abi.encodePacked(prevHash, address(this), nonce));
uint256 roll = uint256(hash) % 16;
console.log('\t'," Dice Game Roll:",roll);
nonce++;
prize += ((msg.value * 40) / 100);
emit Roll(msg.sender, roll);
if (roll > 2 ) {
return;
}
uint256 amount = prize;
(bool sent, ) = msg.sender.call{value: amount}("");
require(sent, "Failed to send Ether");
resetPrize();
emit Winner(msg.sender, amount);
}
receive() external payable { }
}
Contract B
enter code here
contract RiggedRoll is Ownable {
DiceGame public diceGame;
constructor(address payable diceGameAddress) {
diceGame = DiceGame(diceGameAddress);
}
//Add withdraw function to transfer ether from the rigged contract to an address
//Add riggedRoll() function to predict the randomness in the DiceGame contract and only roll when it's going to be a winner
function riggedRoll(bytes32 riggedHash) public payable {
riggedHash = address(diceGame).blockhash(block.number-1); //I am aware this syntax is broken but I am not able to find a legitimate one to access the data from contract A.
}
//Add receive() function so contract can receive Eth
receive() external payable { }
}
A contract doesn't know when it was last called, unless you explicitly store this information.
Then you can get the block hash using the native blockhash() function (accepts the block number as a parameter).
contract Target {
uint256 public lastCalledAtBlockNumber;
// The value is stored only if you invoke the function using a (read-write) transaction.
// If you invoke the function using a (read-only) call, then it's not stored.
function foo() external {
lastCalledAtBlockNumber = block.number;
}
}
bytes32 blockHash = blockhash(block.number);
I am working on a smart contract, and my goal is that when a certain (variable) amount of eth gets send to the contract, it gets split and payed to three adresses. I currently have this code. Am I missing something? It doesn't work in Remix unfortunately. Thanks in advance for your valuable time!
`pragma solidity ^0.6.0;
contract PaymentSplitter {
address payable addressOne;
address payable addressTwo;
address payable addressThree;
uint256 amount;
constructor(address payable _addressOne = 0xAb8483F64d9C6d1EcF9b849Ae677dD3315835cb2, address payable _addressTwo = 0x4B20993Bc481177ec7E8f571ceCaE8A9e22C02db, address payable _addressThree = 0x78731D3Ca6b7E34aC0F824c42a7cC18A495cabaB) public {
addressOne = _addressOne;
addressTwo = _addressTwo;
addressThree = _addressThree;
}
function splitPayment(uint256 _amount) public {
amount = _amount;
addressOne.transfer(_amount / 3);
addressTwo.transfer(_amount / 3);
addressThree.transfer(_amount / 3);
}
function getSplitAmount() public view returns (uint256) {
return amount;
}
// This will be invoked when the contract receives a payment
function() external payable {
splitPayment(msg.value);
}
}`
We tried various smart contract, but without any significant results
I modified your smart contract. I put some notes, to understand you some errors in your logic:
// SPDX-License-Identifier: MIT
pragma solidity ^0.6.0;
contract PaymentSplitter {
address payable addressOne;
address payable addressTwo;
address payable addressThree;
uint256 amount;
constructor(address _addressOne, address _addressTwo, address _addressThree) public {
addressOne = payable(_addressOne);
addressTwo = payable(_addressTwo);
addressThree = payable(_addressThree);
}
// NOTE: Avoid passing parameter with value because with this statement 'address(this).balance' I receive the entire amount of Ether stored in smart contract
function splitPayment() public {
// NOTE: I retrieve entire amount stored in smart contract balance after send value to it
uint smartContractBalance = address(this).balance;
// NOTE: Since smart contract balance should be divided into three equal part the amount, I make this operation one time and put the value inside 'amount' variable. Then
// I transfer the equal amount to three accounts.
amount = smartContractBalance / 3;
addressOne.transfer(amount);
addressTwo.transfer(amount);
addressThree.transfer(amount);
}
function getSplitAmount() public view returns (uint256) {
return amount;
}
// This will be invoked when the contract receives a payment
receive() external payable {
splitPayment();
}
}
NOTE: Consider to use address.call{value}() for send amount from smart contract to accounts.
Is this a better contract? A few changes, and different amounts have to be sent to different addresses.
pragma solidity ^0.8.17;
contract Blockbook{
address payable public address1;
address payable public address2;
address payable public address3;
constructor(address payable _address1, address payable _address2, address payable _address3) public {
address1 = _address1;
address2 = _address2;
address3 = _address3;
}
function splitPayment(uint amount) public payable {
address1.transfer(amount * 0.8);
address2.transfer(amount * 0.1);
address3.transfer(amount * 0.1);
}
receive() external payable {
splitPayment(msg.value);
}
function updateAddresses(address payable _address1, address payable _address2, address payable _address3) public {
address1 = _address1;
address2 = _address2;
address3 = _address3;
}
}
pragma solidity ^0.8.7;
// SPDX-License-Identifier: MIT
contract Client {
address payable private hub;
address payable public owner;
uint256 public balance;
constructor(address payable _hub) {
hub = _hub;
owner = payable(msg.sender);
}
receive() payable external {
balance += msg.value;
}
function withdraw(address payable destAddr) public {
require(msg.sender == owner, "Only owner can withdraw funds");
uint amount = address(this).balance;
destAddr.transfer(amount);
}
function start() public payable {
require(msg.sender == owner, "Only owner can start the process");
uint amount = address(this).balance;
hub.transfer(amount);
balance = 0;
}
function setHub(address payable _new) public {
require(msg.sender == owner, "Only owner can change address");
hub = _new;
}
}
Hi i have a problem, when I deploy this contract and put as input (hub) the other contract, then send eth to this contract, i call the "start" function and throw a gas estimation error.
Someone who can help me pls...
I'm expecting that calling the start function fund will be sent to the other contract that also have a function for receiving eth
receive() payable external {
balance += msg.value;
}
You are getting that gas estimation error because your receive function on the second contract is not empty and the transaction does not have enough gas to execute the code. transfer only sends the amount of gas necessary to execute a transfer of ether (21,000 gas) and nothing more.
You can use call instead of transfer to send ether and set the amount of gas that you want to send. transfer is actually no longer recommended for sending ether.
I have deployed smart contract using remix IDE, launched with Injected Web3 on Ropsten test network. I could call BuyTokens function within solidity IDE successfully, but when tried to buy tokens with metamask from other address transaction get reverted. I can see the difference between those operations on ropsten.etherscan explorer - the difference is in Input Data field.
Metamask transaction has value 0x and transaction via remix is:
Function: buyTokens() ***
MethodID: 0xd0febe4c
Code:
// SPDX-License-Identifier: GPL-3.0
pragma solidity ^0.8.0;
contract Token {
// Track how many tokens are owned by each address.
mapping (address => uint256) public balanceOf;
// Modify this section
string public name = "DemoCoin";
string public symbol = "DC";
uint8 public decimals = 8;
uint256 public totalSupply = 1000000000 * (uint256(10) ** decimals);
address public owner;
//uint scaler = 10e18; // == 1 ETH in wei
//uint public coinPrice = 20; //initial price => 20 cents
event Transfer(address indexed from, address indexed to, uint256 value);
constructor() {
// Initially assign all tokens to the contract's creator.
owner = msg.sender;
balanceOf[msg.sender] = totalSupply;
emit Transfer(address(0), msg.sender, totalSupply);
}
// Might be executed automaticlly
// https://blog.chronologic.network/schedule-your-transaction-now-using-mycrypto-and-myetherwallet-17b48166b412
// function changeCoinPrice() public {
// uint newCoinPrice;
// require(msg.sender == address(0));
// coinPrice = newCoinPrice;
// }
function buyTokens() public payable {
// msg.value in wei so 1ETH = 10e18
// lets set 0.20 cents for 1 token
uint paidAmount;
require(balanceOf[msg.sender] >= paidAmount);
require(balanceOf[owner] >= value);
uint tokens;
tokens = value/10e14;
balanceOf[owner] -= tokens;
balanceOf[msg.sender] += tokens;
emit Transfer(owner, msg.sender, tokens);
}
function msgSenderBalancce() public view returns (uint) {
return balanceOf[msg.sender];
}
function withDrawEth() public view {
require(msg.sender == owner);
}
}
Why these methods are called diffrently? And how to add method id in metamask? Or am I missing something and this should be handled in other way?
MetaMask has a very basic UI. It only allows transfers of ETH and standardized tokens, but it doesn't show any buttons to call other contract functions. It also doesn't allow creating any custom buttons in their UI.
You'll need to set the data field of the transaction to 0xd0febe4c (which effectively executes the buyTokens() function).
But - they also don't allow specifying the data field value manually in the UI, so you'll need to preset it using the Ethereum provider API.
Your web app connects to the user's MetaMask acccount. It opens a MetaMask window and the user needs to manually confirm the connect.
The web app sends a request to MetaMask specifying the transaction with data field value.
The user confirms the transaction (which now includes the data field value 0xd0febe4c) in their MetaMask UI.
The wallet address that is sent through event differs from the one stored in contract
Hi, I have a contract that is deployed to development network through truffle.
I trigger function that looks like this:
struct Round {
bool isValue;
uint32 id;
RoundState state;
address[] addresses;
RoundBet[] bets;
mapping(address => bool) betUsers;
mapping(address => uint256) userBets;
uint256 winTicket;
uint256 amount;
uint256 lastTicket;
address winner;
}
.....
event roundBet(
address user,
uint256 amount,
uint256 start,
uint256 end
);
......
function test() payable public {
Round storage round = roundsHistory[currentRound];
require(round.isValue == true);
require(round.state == RoundState.started);
require(msg.value >= MIN_BET);
uint256 amount = msg.value - msg.value % MIN_STEP;
if(!round.betUsers[msg.sender]){
round.addresses.push(msg.sender);
round.betUsers[msg.sender] = true;
}
round.userBets[msg.sender] += amount;
uint256 sticket = round.lastTicket + 1;
uint256 eticket = sticket + amount;
uint256 length = round.bets.push(RoundBet(true, sticket, eticket, msg.sender, amount));
round.amount += amount;
round.lastTicket = eticket;
if(round.addresses.length == 2){
round.state = RoundState.running;
emit roundTimerStart(currentRound);
}
emit roundBet(msg.sender,amount, sticket, eticket);
}
AS you can see I emit roundBet event at the end of function call. The problem is that value of "user" of that event differs from msg.sender that is stored in round.addresses(values stored in round.addresses - is currect and the one emited - is wrong)
If you are using Metamask, keep in mind that it does not switch the account set as msg.sender to the contract, it seems to use the first account (0) to sign every transaction.
We encountered the same problem during a school project.
First of all about platform. It was tron not ethereum. May be in ethereum there is no such issue.
So what I did:
I do not pass address in event. I save it in internal structure
In event I do pass index of saved address in structure
I've wrote a separate method that returns address (and other usefull info) from internal structures by its index.
So by using this workaround I was able to get needed information from contract.