All Questions

Im looking for a way to call a contract that is deployed on the ethereum main network using Go (or JS/anything). From what i can see the foolproof way is to do so over json RPC but i would love to ...

As we all know, the more address there are, the more bytes the MPT tree (Merkle Patricia Tree) saves and there may be 35 million active address in Ethereum. If we put all 35 million active address ...

Normally in MIST, we have to mine by miner.start() to deploy the smart contract. But in Remix we don't need to mine. Can someone tell me why is that ?

I am attempting to write some unit tests as I'm working on the development of some smart contracts, but I've run into an issue that's preventing me from continuing. I'm attempting to check the address ...

I am trying to deploy my contract onto the blockchain in my private network with local private key (no wallet: I used web3.auto.w3.account.create()). I know how to send normal transaction with local ...

I installed Ethereum 0.9.1 from Github on iMac running macOS 10.12.6. Synching 6 days now & still going. Documentation on all things Ethereum is garbled to say the least. Does anyone know if I now ...

While creating a web3 instance, and attempting to call setProvider with a valid provider (Ganache), I get a TypeError. TypeError: Cannot read property 'clearSubscriptions' of undefined Steps to ...

I set up a contract with three files referring to Token Factory. I make a test on remix online tool, they can be successfully compiled. when I'm tring to compile them by solc module in a .js file, ...

I implemented selfdestruct(), also it showed succeeded on Etherscan. Afterwards, I still am able to send transactions to the contract. Can you tell me why? Doesn't selfdestruct() delete the contract ...

I know transferring ERC-20 token from my wallet to a custom contract. The smart contract has to call transferFrom() to enable withdraw. ERC20 token = ERC20(_tokenAddress); token.transferFrom(msg....

I have created a test token and deployed it on the ropsten test network. I have the full balance in my ether wallet. My question is how can I transfer this token to other wallets? How can I configure ...

I am having trouble deploying my smart contract to the ropsten network using infura and truffle am getting error that says "var sig = secp256k1.sign(msgHash, privateKey); ^ ...

I'm building a private blockchain with Parity clients. For performance testing, I'm submitting many identical transactions. One of the nodes has a GPU miner attached. There are 2 issues I cannot ...

Currently I'm using this to do ens lookups: https://etherscan.io/enslookup But is there a public API I can use to do queries to see what each ens goes to?

I'm trying to listen for an event I've created on remix IDE , from NodeJS. I call a smart contract method from where the event is triggered and I'm waiting for it in my console...but I don't receive ...

I am unable to find the correct API call format to download the input data field from the event log of each transaction - is there a way to use API key to download this information? I am referring ...

LemonEmail looks like a very interesting implementation of 100% decentralized messaging system with end-to-end encryption. From what I understand from the information available, it uses the Ethereum ...

I'm running the following services in docker: go-ethereum 1.9.11-stable-6a62fe39 in light mode python 3.7-alpine app with Web3 v5.5.1. Geth node startup is straightforward: image: ethereum/client-...

okay so i am making a mobile application where i want to place the ERC20 wallet with that application ? so my question is : is it possible to do this ? how much will it be secure ?

Playing around with the gnosis multisig, using truffle-contract to interact with already deployed MultiSigWallet using truffle migrate. Contents of the file I am trying to run: var contract = ...

TL;DR - Replicated Ethereum Blockchain. Running Local Node. Connecting Local Node to Web3.js in browser using RPC. Want to create addresses & send transactions Details - I have a blockchain that ...

Hey I'm calling externals contract method transferFrom in following way. function sendTransaction(address tokenAddress, uint tokenAmount) public payable { if (!performTransfer(tokenAddress, ...

I have a wallet at MyEtherWallet.com . Is there any API which allows me to transfer Ether from my account to different accounts ? Does MyEtherWallet provides any such API's ? I saw the documentation, ...

I transferred eth to my parity account and then to my parity wallet. I accidentally erased the account, and it also erased my wallet. I got them back, but now my wallet is stuck in my addressbook. I ...

our project now uses scheduled task to query the eth address with infura API to get its balance every 10 seconds but as the number of addresses keep increasing, the efficiency is very bad. Is there ...

Getting error with this code **/* Meta Mining Token https://github.com/Overtorment/MetaMining */ import "https://github.com/OpenZeppelin/openzeppelin- solidity/contracts/token/ERC20/...

I want to get events from block X. I have: quorum-v2.4.0 web3js 1.2.6 And I have my own smart contracts I want to listen for. So I have created listener for allEvents like this: const event = ...

I am trying to deploy contracts to Ganache for testing using Truffle, but no matter what I set gas price / gas limit / gas to both in truffle.js and Ganache itself, it always get check gas amount on ...

I am using web3 1.0 and testrpc, The following is my contract. pragma solidity ^0.4.18; contract LocalEthereum { event Created(bytes32 _tradeHash); uint32 value = 0; function addValue() ...

Here's my code, including the caller and called contract: pragma solidity ^0.4.24; contract Called { string info = "default"; function setInfo(string _info) public { info = _info; ...

Whenever someone buys a smart-contract the amount (in Wei) get stored in SC(Smart Contract) address(this) += msg.value. Now I am trying to create a function to redeem the balance of the SC ...

When I run the TestRPC client (ganache-cli), it provides me with 10 different accounts and private keys along with a local server at localhost:8545 Available Accounts (0) ...

Take look at my contract transaction history: https://ropsten.etherscan.io/address/0xe42d26e4a66e9562b40bde44e4ceff706fd67d20 I verified my contract so you can see everything using etherscan ...

Hello I am trying to set up a private ethereum instance with geth on MacOS I have a startnode.sh file using ATOM But every time I try to start the node with "./startnode.sh", the http access account ...

I have running a private blockchain with 4 nodes, and when i'm creating my Dapp, i have specified for the web3 address only one node ( Ip; port, RCP) So, my question is , how the others nodes ...

I have this type of list of contact numbers, [0825623456,0838956234], that I am storing inside solidity in uint256[] array. But when I get the list of that number in console or web application , I can ...

I was on the Ethereum Wallet's test network and finally worked out all the code, but now that I have switched over to the main network I've had to download a lot of the preexisting blocks and has my ...

I have private Ethereum network running on my local network with two sealer node and one bootnode. I have deployed the private blockchain and configured it using geth. Now I want to create another ...

I am creating a smart contract, so inside that I have to pass the token in contract and the value of ether will be calculate on behalf of token price please help.

Starting with a simple example. If you just encode a single string like, abi.encode("AAAA"); You get the following output (96 bytes, 3 words) ...

i am following this tutorial tutorial under the section Working with smart contracts with Java smart contract wrappers i followed the same steps but i am getting RunTimeException here is the full ...

I have an event with two indexed arguments orderId and status. Filtering works fine when I filter the event on orderId which is uint. I am not able to filter the events on the second argument (status)...

I'm trying to deploy a trivial faucet program which compiles OK with remix but I get the following error. "Gas requirement of function Faucet.withdraw(uint256) high: infinite. " This means that while ...

truffle-config.js module.exports = { compilers: { solc: { version: "^0.6.0" } }, networks: { development: { host: "127.0.0.1", port: ...

I'm trying to link my contract to an external library by defining an interface contract that defines the library functions and the main contract that refers to the actual library address. My library ...

quick question... ... I have a remote host running Parity which I can connect to via an SSH Tunnel. I've forwarded ports 8180, 8546 and 8646 through the tunnel to the computer running Parity. I can ...

Is there any way that i could run a shell script after a contract is deployed,since the terminal has geth Javascript console running,and there are some commands which are already in the shell script. ...

I am looking for a way to execute a transaction locally (using local geth/parity node) for simulation only, before actually submitting it to blockchain. I know that I can use 'eth_call' RPC call and ...

System information Geth version: 1.8.8-stable-2688dab4 OS & Version: ubuntu I'm currently created private ethereum network using puppeth, when I created a sealer/ miner, appear this question "...

I built a local private chain, and created an account via geth. Then I switched to test net from metamask. After that, the account started to lose ether. People sent the ether in that account to ...