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2
votes
1answer
40 views

Why Ethereum sets user balance to MaxBig256 whenever a contract query is performed?

There is a strange behaviour on user wallet balances when performing a contract call (that is supposed to have no cost). Balance is right (expected value) until a free call is requested to a contract. ...
0
votes
0answers
11 views

ethereum whisper's method 'addPrivateKey' returning different keyid pair for same private key

Can somebody please explain why running this code produces different key-id pair each time? Is it not supposed to be unique for a given pvt key? web3.shh.addPrivateKey('...
0
votes
0answers
25 views

Getting empty events in response of receipt. I am using Infura+web3.js+ropsten

JS code contract.methods .myFunction( "data1", 1568545262, 1568631662, 1568718062, "0xD4496dA2a4b376fC8s4d786EB6B71483436077c4" ) .send({ from: "...
5
votes
2answers
37 views

Pros and Cons of smart contract upgradable patterns

There have been quite many arguments around how to achieve smart contract updates like Upgradeable smart contracts. I feel Proxycontract with Delegate-call is currently the most famous one. But aside ...
0
votes
1answer
22 views

Error : migrate kovan

From : truffle migrate --network kovan >> ProviderError: VM Exception while processing transaction: revert >truffle migrate --reset --network kovan Warning: Both truffle-config.js and ...
1
vote
1answer
13 views

How to verify the sha256 result of integer 5 in the Zokrates tutorial?

The Zokrates tutorial here starts with calculating the SHA256 hash of (the number) 5. The hex representation of the result is shown at the bottom here: However, I could not reproduce this on my ...
0
votes
0answers
11 views

what to sign to close the contract on JVM?

Full Contract I cannot sign the message correctly thus failing to close the contract.
0
votes
2answers
40 views

How to save an array of address?

I wrote a smart contract PersonalInfo.sol. In this smart contract, I want to save an array of address. Each address is the place where smart contract were deployed. However, each time I deployed the ...
0
votes
1answer
16 views

How DApp actually talks to Ganache ethereum node?

Both Metamask and web3.js seems to be enabling a DApp communicates to a remote ethereum node. There are a few different aspects to developing blockchain applications with Ethereum: Smart ...
1
vote
0answers
18 views

How to allow mobile wallets to sign and access to my dapp

I'm building a dapp application on Ethereum using React & Web3js. As usual the dapp will get the injected provider from Window.web3 (MetaMask), perhaps. The problem that I'm facing now is how can ...
0
votes
0answers
35 views

Why my geth fast node suddenly stopped running?

Fatal: Error starting protocol stack: gap (#3) in the chain between ancients and leveldb when I run geth node for ropsten by : geth --testnet --syncmode "fast" --cache=512 --rpc --ws --shh console ...
0
votes
0answers
21 views

contract not deployed [on hold]

I am getting this error in the browser console and dont what to do please help... ERROR Error: Uncaught (in promise): Error: Contract has not been deployed to detected network (network/artifact ...
0
votes
0answers
5 views

I need to transfer my ETH from JAXX to Coinbase [closed]

I have 0.15260000 ETH in JAXX, which I want to transfer to my Coinbase account. I have the original QR code in JAXX and the 'current etherium address' as a screen shot that Jaxx generated when I ...
0
votes
1answer
53 views

Web3-core-helpers error: Uncaught (in promise) Error: Provided address “undefined” is invalid,

When I launch the app with with react.. this error occur when my exchange contract is loaded.. Here is the code i wrote to talk to the blockchain: export const loadBalances = async (dispatch, web3, ...
0
votes
0answers
16 views

how to deploy usdt contract through remix browser [closed]

pragma solidity ^0.4.11; /** * Math operations with safety checks */ library SafeMath { function mul(uint a, uint b) internal returns (uint) { uint c = a * b; assert(a == 0 || c / a == b);...
1
vote
1answer
22 views

Useful resources to help understand go-ethereum source code

I am new to ethereum community and I want to study the implementation of Ethereum (e.g. geth) and contribute to the go-ethereum project. However, I find the source code hard to understand by only ...
0
votes
0answers
31 views

What is the difference between calling this two function from another contract by interface? [closed]

interface ERC20Interface { function transfer(address _to, uint256 _value) external; // <---- A function transfer(address _to, uint256 _value) public returns (bool success); // <---- B ...
0
votes
1answer
22 views

MetaMask listed as “web wallet” on official Ethereum website

MetaMask is listed only in the "web wallets" section of the official Ethereum wallet guide. Obviously, MetaMask is written in Javascript and runs in a web browser. But this is also true of the ...
0
votes
0answers
13 views

How to setup clef signer with clef --stdio-ui

I have geth running on rinkeby network and successfully used clef as a signer using command. clef --keystore ~/.ethereum/rinkeby/keystore --chainid 4 --stdio-ui Also started geth with clef as ...
1
vote
0answers
8 views

fail for read ethereum node base on leveldb.py

I installed leveldb base on python3.6.but when I using leveldb.LevelDB import path for files to be read. a error occered "leveldb.LevelDBError: Corruption: 3 missing files; e.g.: D:/downloads_by_geth/...
0
votes
1answer
30 views

Detect failed token transfer via RPC

It seems like Etherscan can detect failed token transfer even though the transaction itself is successful and the gas isn't used completely. Like in this transfer of Huobi Tokens Is there a way to ...
0
votes
1answer
17 views

Coinbase to Bittrex deposit gone awry? Eth vanished despite being sent to correct address [closed]

Can somebody help me figure this out? I sent ~1.258 Eth from Coinbase to my Bittrex wallet address a couple hours ago and, despite being confirmed and sent to the correct address, it seems to have ...
0
votes
1answer
26 views

How to access Struct field dynamically

I have a struct struct lineItem { string idNo; string date; string code; string docCode; string vendorNumber; string invoiceDate; string ...
0
votes
0answers
91 views
+50

Remix never returns a transaction - but everything works - why?

This code supposedly works. Its supposed to let the owner withdrawal collected ERC20 tokens in a contract. It calls the balanceOf() for the erc20, then calls transfer(). Only have this error when ...
0
votes
1answer
59 views

MetaMask - RPC Error: Internal JSON-RPC error

I am getting this error when i trying to use metamask on my local for a simple transaction from one account(say A) to another (say B). code: -32603 data: {originalError: {…}} message: "Internal ...
0
votes
1answer
34 views

Ethereum Smart contract calling a function in another smart contract that has a address payable return value give error

I am new to solidity. Anyway, I have written the following smart contract: pragma solidity >=0.4.22 <0.7.0; contract SP { address BlockAddress; bytes32 _Mhash; function ...
1
vote
1answer
8 views

What is the unit for the tx.gasprice?

Is it a wei, kwei, mwei, gwei, ... Something else? The API doesn't say much.
0
votes
1answer
20 views

Loading modified contracts keeping the same super class

I am trying to implement upgrade of contracts. One pattern by [1] is to have a layer to resolve the actual address of a contract. I implemented that adding the Pausable manipulation. My idea was to ...
0
votes
1answer
20 views

How to parse ecrecover parameters?

I am looking into getting the public key from ANY ethereum address (not owned by me) that has sent a transaction at least once. It seems that the most viable solution here would be to use ethereumjs-...
1
vote
1answer
14 views

Forks of Metamask

Are there forks of metamask to be used to end-users in a permissioned network? In other words, I would like to: - hide public networks (to avoid confusion) - pre-configure that the user should use the ...
1
vote
1answer
14 views

Event Names not showing up on Etherscan

For some reason Event Names associated with transactions to my contracts aren't being shown in their Event Logs on Etherscan. Worth noting, this event in particular is not indexed. Any thoughts as to ...
1
vote
2answers
65 views

How to check Ethereum smart contract info?

I want to know 3 things: Is an address a smart contract? Is this smart contract an ERC20 or ERC721 token? Is the Solidity code public?
1
vote
1answer
19 views

Duplication of events in permissioned geth Chain with clique PoA consensus algorithm

I have an Ethereum chain running on my local host via geth and i am using the clique PoA Algorithm. I have 4 authority nodes so the number of Nodes allowed to sign a block should always be 1 because ...
1
vote
0answers
30 views

Any C library available to interact with an Ethereum smart contract?

I need a C library that enables to create, sign transactions and interact with the smart contract.
0
votes
1answer
35 views

truffle migrate --network kovan >> ProviderError: VM Exception while processing transaction: revert

I am a beginner. I can deploy to a private network but I can not deploy to a public network. I need a Deploy to the kovan test network. please help me. >truffle init >npm install truffle-...
0
votes
2answers
32 views

Quorum Development [closed]

i am looking for in depth development reference for JPM Quorum blockchain, i am not able to find anything other than the basics. If anyone has any good resources please share them with me. to be more ...
0
votes
1answer
14 views

View sendTransaction implementation

I'd like to see code that implements getAccounts and sendTransaction in a provider. I tried digging into the Metamask source code and found the line where Metamask supplies the Web3 provider, but I ...
0
votes
1answer
28 views

Storing transactions result into database

I need to store the transaction details to my database. And here is my code: var rawTx = { nonce: nonce, gas: estimate_gas, to: contract_add, value: '0x0', ...
1
vote
1answer
24 views

str.slice is not a function

I ran two command lines of web3 and it returned an error > length ='0000000000000000000000000000000000000000000000000000000000000002' ...
0
votes
1answer
37 views

One contract accessing data from another fails

I am trying to get two contracts to interact: pragma solidity ^0.5.10; contract C2 { address public addr; constructor(address per) public { addr = per; } function ...
0
votes
0answers
18 views

Contract deployed successfully on localhost and mainnet, but gives error on rinkeby and ropsten

I tried to deploy a contract to rinkeby then on ropsten, but getting an error: Network ropsten-fork Minting initial supply of 5000000000 ... Error: Error: Error: invalid address (arg="_to", coderType=...
2
votes
1answer
12 views

Does the Raiden client ever deploy TokenNetworkRegistry?

Is there any code in the Raiden client that deploys a TokenNetworkRegistry contract?
0
votes
0answers
17 views

ethereum hash is not searchable in parity private network

I did this in rospten network, but when I use it in private parity network, I get transaction hash, but it isn't searchable at the explorer: const Web3 = require('web3'); const EthereumTx = require('...
1
vote
1answer
25 views

In Raiden's source, why is a result of state transition called “iteration”?

Throughout the Raiden source code, the result of a state transition is called a iteration (for example https://github.com/raiden-network/raiden/pull/4791#pullrequestreview-285494821 ). Where does ...
0
votes
1answer
25 views

While importing web3.py getting following error: TypeError: 'ellipsis' object is not iterable [closed]

Python version : 3.5.2. web3 version : 4.9.2. Ubuntu : 16.04. Also tried previous version of web3: 4.0.0
-1
votes
0answers
38 views

Update a non-upgradable ERC721 contract [duplicate]

I'm trying to add some extensions to the ERC721 token standard. Usually, contracts should be desgined to be upgradable before deployment. The problem is that the contract is already deployed and the ...
0
votes
0answers
25 views

Simple functions and constructors not working

I am working with a private blockchain, and am having a problem where simple functions and constructors simply fail to work. For instance: constructor(address admin) public{ owner = msg....
0
votes
3answers
39 views

Publish and verify the source contract code in Ethscan. I tried it but it keeps failing. Can anyone help me?

this is the token: MovieMarketCoin https://etherscan.io/token/0xa0005edc8897fe1f9e2705a1682431497a504657 Source code is here: https://github.com/Gh4Algebra/MovieMarketCoin I followed other answers ...
1
vote
1answer
34 views

How to get top 5 token holders?

I want to keep a track of top 5 token holders inside the contract in terms of their token balances, is there any efficient way to do that in solidity?
0
votes
1answer
25 views

Weighted Random Number Array generation in solidity

I have an array like this in the array, uint256[] public numberArr= [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]; Each number in an array have their own weight, uint256[] public weightNumberArr = [1, 3, 9, 7, 15,...

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