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how can I get the account locked information via python web3?

There is a command personal.listWallets in geth cli to get the account locked/unlocked status such as below: > personal.listWallets[1] { accounts: [{ address: "...
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0answers
12 views

gas estimate is null

The code is working in Remix but in geth it is showing the Node error: {"code":-32000,"message":"gas required exceeds allowance (8000000) or always failing transaction"} BUt the gas required by ...
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0answers
4 views

Accidental TRX ERC20 transfer from MEW to Poloniex

I sent TRX Tokens that were saved in my Ledger Nano S in ETH. I accessed myetherwallet to send the TRX tokens to Poloniex. I used the ETH Address of my Poloniex Account and I transferred the TRX. It ...
0
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0answers
8 views

Downgrade version of evm

I've installed the evm via apt-get, it returns me an unwanted version which is newest one. I've tried to find the older version to install but it returned nothing. I want to get evm version 1.7.3. Is ...
0
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1answer
7 views

Solidity. Concatenate hash w address. TypeError: Operator + not compatible with types string memory and address payable

I am trying to do something simple: examsFinalHash = keccak256(examHash + msg.sender); but I get the following error: TypeError: Operator + not compatible with types string memory and address ...
0
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0answers
5 views

How do you mint tokens on Compound Finance with Infura and Web3

I'm new to Compound and I'm trying to get minting/redeeming implemented in my app using Infura (Ropsten) as my httpProvider for Web3. I understand that Infura doesn't allow invocation of ...
0
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0answers
4 views

Fixed time between blocks like Ganache

I am trying to establish an Ethereum network and study its TxPool. I tried Ganache, but it looks like it doesn't support TxPool yet, but I found the fixed time between blocks and no difficulty (...
0
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1answer
6 views

Size limit to number of items in a struct

If I loop over mapping into a struct the gas fee is very low. However, in trying to test its limits, the EVM often causes Remix to crash in creating edge cases, because I'm creating blocks of 50 new ...
0
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0answers
5 views

Get key for coinbase account in go-ethereum SimulatedBackend

What's the best way to 1) pre-fund 2) get a signing key for the coinbase account in the go-ethereum Simulated Back-end? Right now the simulated back-end coinbase account seems to default to 0x0 but I'...
0
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1answer
14 views

Solidity: Is there any way to store the start time of solidity code? now() function returns block.timestamp only

I wanted to get a start time of solidity code, so I used now() previous which only returns block.timestamp whenever the solidity got started. Is there any way to store or know the start time of ...
0
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0answers
12 views

Does it make sense to require token value to be anything but negative to prevent hack (more details below…)?

I was asked to validate a smart contract for a token and a function that puzzled me looks like that: function transferFrom(address _from, address _to, uint tokens) { require(...
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0answers
18 views

blockchain solidity tracking system

I am trying to make a code in solidity to add items to a blockchain which contains items and their tracking history (like when trace your order online for an item) (which at first are located in "...
1
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0answers
7 views

Isn't proof-of-stake too risky for stakers, given the volatility of ETH?

As I understand it, proof of stake involves staking some ETH for a fixed number of months, and getting the ETH back - with interest - at the end of the period. But, being volatile like most ...
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0answers
5 views

Chain ID of Remix Javascript VM

I am attempting to test out a simplemultisig contract (https://github.com/christianlundkvist/simple-multisig) but it requires the chain id. I have been testing using ganache but wanted to switch to ...
0
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0answers
12 views

Curl Request Java - How To

I am looking to use some of the management admin API's found here: https://github.com/ethereum/go-ethereum/wiki/Management-APIs but unfortunately, the web3j library does not support the calls that I ...
-1
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0answers
15 views

Working with CEth and web3js in Compound Finace [on hold]

What could be the best way to initiate a borrow activity while using web3js interacting with Compound Finance: const cToken = CEther.at(0x3FDB...); await cToken.methods.borrow(50).send({from: ...
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0answers
15 views

Backward program analysis (like symbolic backward execution) tools for smart contracts

I know there are some backward program analysis tools for traditional softwares, but i wonder if there are already backward symbolic execution tools for smart contracts, or any tool that I can refer ...
0
votes
1answer
37 views

How to use array of arrays with mapping in Solidity

I'm developing a smart contract handling document signing. Mainly, there are two things to consider 1) Signers 2) Sign Types. 1) Signers: Mandatory sign the document 2) Types: Types of signs such as ...
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0answers
22 views

creating transaction with dynamic arguments (objects/variables)

My scenario is to make transactions (deploy contract, calling its functions, etc.) with arguments (which are dynamically created/extracted from some json abi file). For example; function ...
0
votes
1answer
19 views

Erc-20 Token Send Transaction

I want some Information about Erc-20 Transactions. I want to transfer Erc-20Token from first wallet to a second wallet, I have Privet Key, But I want to transfer with Api, So How can I transfer the ...
0
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0answers
9 views

accceptOwnership Tx “Returned error: nonce too low”, though getTransactionCount(account) gives a nonce that looks ok

Could anyone let me know what is wrong with the code below? Before executing the below code, transferOwnership(newOwner) went through successfully. And then, I execute the below code, "Error: ...
1
vote
1answer
14 views

TxPool on Ganache

I started using Ganache to run Ethereum and tried via cURL the following: curl -X POST -d '{"jsonrpc":"2.0","method":"txpool_status","params":[],"id":1}' http://ip:port But I got the message: ...
2
votes
1answer
14 views

let user create and sign erc20 transactions but i pay the fees?

I try to build an app where users can send and receive ERC20 tokens. I want the transactions for my user to be feeless. So is it possible for a user to create and sign the transactions, my system ...
0
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0answers
23 views

Error: Returned values aren't valid, did it run Out of Gas based on YT Tutorial

I red the other Threads about this case, but couldn't fixed the problem. I got this tutorial for Scmart contracts: https://www.youtube.com/watch?v=coQ5dg8wM2o&feature=youtu.be However the ...
0
votes
1answer
24 views

Deleting structure and gas refund

contract SomeContract { struct ImportantInformation { uint256 a; uint256 b; uint256 c; uint256 d; uint256 e; address f; } ...
0
votes
0answers
10 views

Privatenet Blocktime

I want to run some experiments on my private net where I can try faster and slow Block times - I know on clique you can set it to: Clique: &CliqueConfig{ Period: 15, But I don't see ...
1
vote
1answer
17 views

Remix compile error: Expected primary expression

function Renting() public { checkUser[owner] = true; struct govt = Person(owner, 'Owner', 'Owner', 0, 'None', new uint[](0), new uint[](0)); addressToPerson[owner] = govt; } When I try ...
1
vote
1answer
26 views

fraction**veryLargeNumber type math in EVM

A fraction like 0.5**1/31556926, raised to an exponent in the range of 10^9. What are the best ways to do that in a smart contract?
0
votes
1answer
14 views

Truffle Migrate for metacoin truffle box example failing

truffle migrate Compiling your contracts... =========================== > Compiling .\contracts\ConvertLib.sol > Artifacts written to C:\blockchain_projects\truffle_projects\metacoin\build\...
1
vote
1answer
14 views

Automatically extracting functions names and parameters from ABI JSON file

I have done some work on captioned subject. For example, I can extract all getter functions (and some constructors as well) of all given smart contracts (in abi json file format). Then i can call (...
0
votes
1answer
20 views

How do I fix it? To be able to send eth from smartcontract to the address

Frontend class App extends React.Component { state = { address: '', } async componentDidMount() { await window.ethereum.enable() this.w3 = new Web3(window.ethereum) const ...
0
votes
1answer
23 views

Ethereum Petabyte Storage Problem

As the need of blockchain systems grows so will be the storage issues and the cost of handling such large amounts of data. Is ethereum capable of handling petabyte storage or is it upto an ...
1
vote
1answer
13 views

EVM is sandboxed program execution environment

I read following content about EVM: It is vital to also note that EVM operates in a sandboxed environment- it is totally isolated from the main Blockchain network, and works perfectly as a testing ...
0
votes
1answer
13 views

MetaMask - RPC Error: Error: [ethjs-rpc] rpc error with payload

I have created a DApp. In all my functions where I have used send() function of web3, I am facing above error. I have a function in which I used call() and it worked fine but all send() using ...
0
votes
1answer
10 views

How can I add new contracts generated from a factory to my drizzle-react app?

I have a Factory contract which creates new contracts. How do I get the new contract into my drizzle-react web app? I am using to send the transaction to create a new contract but I don't know how ...
0
votes
0answers
11 views

Blockchain Performance Metrics

How can I measure blockchain execution time, latency and throughput? Which API do I use to measure? Anyone suggest any article or book for me to read about the blockchain performance metrics?
0
votes
0answers
17 views

How to build a P2P wager contract with Solidity

I am looking to build a contract with Solidity that will take wagers on a football game between a bunch of friends. Each user should be able to place a bet on either team, with each bet to be added to ...
0
votes
0answers
12 views

How do I get the value from the event to be displayed on the webpage? [duplicate]

I can connect and console.log the event. But can't bring the value to display on the webpage. I don't know what to do. Front-end import React from 'react'; import logo from './logo.svg'; import './...
0
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0answers
33 views

Track incoming transaction of an account with web3js [on hold]

How to track an ethereum address and get notifications when someone transfers ether to that address?
1
vote
1answer
37 views

Are Solidity numbers little endian, or big endian padded left?

Solidity says it stores numbers as little endian... but I don't understand how thats possible given that they are left padded. const a = new Bn(256) const b = new Bn(256 * 256) a.toArray('le') >&...
2
votes
1answer
19 views

Total metamask balance

I am curious how to get the total current balance of my metamask wallet with as many "accounts" inside it as it bears in the moment? As I can understand metamask is the HD wallet and all my addresses ...
0
votes
0answers
12 views

Geth console stuck at Smartcard socket not found, disabling

My node is running well in the last month. But somehow I restart the node and currently couldn't start probably, keep stuck at smartcart socket not found: INFO [11-15|21:22:32.178] Maximum peer count ...
0
votes
0answers
25 views

Opera wallet web3 problems

I am writing a Dapp. I'm not an expert. It works perfectly on Edge, Firefox, and Chrome (with MetaMask). But I get the following error on Opera when the cryptowallet is on but not synced: { "error":...
0
votes
0answers
7 views

Quorum Maker for recovery of blockchain data in secondary node

We are trying to setup multiple nodes in QUorum maker to make one node as a backup to be used in case the primary node fails for some reason. We are able to deploy our smart contract successfully but ...
1
vote
2answers
29 views

loop though all the members of a map

I need to loop though all of the members of a map and change their property (which is a struct). the way i'm doing this is when adding a member to the map object also save it's address inside an ...
0
votes
0answers
28 views

What do I have to do to call this events to be display on the web page?

How do I call showLottery to display on my webpage? Front-End class App extends React.Component { state = { address: '', lottery: '', events: '', } async componentDidMount() { ...
0
votes
2answers
14 views

Getiing error in remix while using oraclize

Getting this error" called function should be payable if you send value and the value you send should be less than your current balance" even when i set value
0
votes
1answer
17 views

Could not call contract function with its signature

Web3.js documentation says here that the methods of a smart contract are available through: The name: myContract.methods.myMethod The name with parameters: myContract.methods['myMethod(uint256)'] The ...
1
vote
1answer
44 views

web3.eth.getCode doesn't return the data shown on etherscan

For example, let's take contract address 0xdac17f958d2ee523a2206206994597c13d831ec7. Does anybody have an idea why the following two are totally different: The string returned from await web3.eth....
1
vote
1answer
30 views

Web3: can last block be replaced?

I'm using web3py's getBlock function to get the latest block. I am right now caching the latest 50 blocks so that I reduce the amount of workload in my geth node, and to improve overall speed in my ...

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