“Nonce too low” using contract.methods.myFunction().send()

Using web3 to build a contract from the ABI: contract = new web3.eth.Contract(JSON.parse(abi), ‘0x17c91A5a6f5e3E4BEaFC478D18C4A44D88833277’, { from: ‘0x0Ad2b5CCe78D677fD000698a7E4Cde866DE189C6’, gas: 100000}) contract.methods.myFunction(‘constructorVariable1’, ‘constructorVariable2′).send() First send completes successfully. Second+ send returns the error: nonce too low Truffle v5.1.13 (core: 5.1.13) Web3.js v1.2.1 Ropsten testnet Infura as HDWalletProvider node I can’t find any documentation on manually increasing the nonce…

Importing OpenZeppelin loads all node_modules contracts into Ganache

I install OpenZeppelin’s contracts npm install @openzeppelin/contracts Create a contract: pragma solidity ^0.5.0; import “@openzeppelin/contracts/token/ERC20/ERC20Mintable.sol”; contract NewCoin is ERC20Mintable { constructor() public { } } truffle compile (successful) When I load Ganache it imports every single node_module contract into the “Contracts” tab and the program rapidly starts OOMing. truffle migrate then kills it completely. What…

What if John McAfee is right about 1 Bitcoin = 1 million USD by late 2020? Will this “Bitcoin halving” be the catalyst?

The next Bitcoin Halving will take place on May 20th 2020. It will be the third time, that the block reward of the most known blockchain will be halved. As a consequence, miners will earn 50 percent less BTC for every generated block. Experts are expecting, that this development could change the value of bitcoin.…

Undeclared identifier. “costOfAppeal” is not (or not yet) visible at this point

Code: pragma solidity >=0.6; abstract contract TestContract { function costOfAppeal ( bytes calldata _data ) external virtual view returns(uint cost); modifier Fee(bytes memory _data) { require(msg.value >= costOfAppeal(_data), “Not enough ETH”); _; } } It gives the following error: Undeclared identifier. “costOfAppeal” is not (or not yet) visible at this point. How to fix the…

Unable to deploy contract on Private Quorum Network

We just built a new 3 node quorum network but we are unable to deploy any contract on it. Please find the below info: Quorum vesrsion: Geth Version: 1.8.18-stable Git Commit: b5266cbd194aaa61efd1815df87c7d9edaad118c Quorum Version: 2.4.0 Architecture: amd64 Protocol Versions: [63 62] Network Id: 1337 Go Version: go1.13.8 Operating System: linux GOPATH= GOROOT=/usr/local/go genesis.json { “alloc”:…

What is the use of a interface or function without implementation?

Take, for example, this code. The interface contains function without implementation, so how it’s useful. pragma solidity ^0.5.0; interface Calculator { function getResult() external view returns(uint); } contract Test is Calculator { constructor() public {} function getResult() external view returns(uint){ uint a = 1; uint b = 2; uint result = a + b; return…