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1answer
110 views

What are options re: transferring ETH and ERC-20 tokens out of Mist without having to synch?

I have some ETH and many custom tokens sitting in a Mist wallet that will take many days to synch. I assume I can use the 'transfer from' function to move these tokens from this wallet without having ...
0
votes
1answer
8 views

How to set a transaction timeout in txpool properly?

I want to limit transaction pending time to 5 seconds, after that the transaction considered as failed; does --txpool.lifetime solve the problem ?
0
votes
0answers
6 views

Can a factory-contract access/read/modify variables in generated child-contracts?

at the moment I am experimenting with the factory/child-logic in solidity. With my factory contract I am able to create child contracts in which an auction is executed. Now I want to return a variable ...
0
votes
0answers
5 views

PIVX fork CryptoDezire Coin SendRawTransaction not working

A CDZC coin basically fork of PIVX . I am trying to send coin via rpc calls. Successfuly created RawTxn, SignRawTxn but unable to SendRawTxn. `await rpc.listunspent().then(async r => { ...
1
vote
1answer
95 views

ERC721 “Digibles”: different than Bitcoin colored coin concept?

As I understand ERC721 contracts, in particular Cryptokitties, a cryptokitty is not associated with a piece of ETH but rather is just some storage associated with the Cryptokitty smart contract. Is ...
0
votes
1answer
27 views

Solidity - Creating child contract

Recent code: pragma solidity ^0.5.11; pragma experimental ABIEncoderV2; contract Master { address Pi_C_Owner; address payable public NewAuctionPayable; //Hilfsvariable um ...
0
votes
2answers
48 views
+50

How to send ETH to address(0) from msg.sender address using multiple token's contracts, with Solidity 5.x?

I need the safest way for an user to send any amount of Ethereum to address(0). The amount is calculated by the contract, and there is no limit (assuming there is enough funds). All the code I could ...
3
votes
1answer
206 views

Parse arbitrary bytes input

A function recives bytes as input: function foo (bytes data) How do I parse that into individual byte32 chunks? function foo (bytes data) returns (bytes32[]) My goal is to understand how to handle ...
14
votes
3answers
8k views

Export Parity private key

Good afternoon all. Been searching around for an answer to this question and can't seem to find the exact solution I need. I have an ETH account on my Parity node that I want to move to Ethereum ...
0
votes
1answer
166 views

How to send ERC20 to 0x0000000000000000000000000000000000000000

How to send ERC20 to 0x0000000000000000000000000000000000000000 I have tried to do this on myetherwallet and it will not send as a transaction, is there a special way to send here? Thanks
0
votes
1answer
10 views

Quorum permissioned network

How can I permission a quorum network? Imagine I have 3 nodes in my network and I install another node in my friends house. How can I prevent my friend add more nodes to my quorum network? thanks
1
vote
1answer
234 views

truffle-contract cannot deploy in node js

This is the error I get. internal/modules/cjs/loader.js:631 throw new ERR_INVALID_ARG_TYPE('id', 'string', id); ^ TypeError [ERR_INVALID_ARG_TYPE]: The "id" argument must be of ...
0
votes
1answer
228 views

No etherbase set and no accounts found as default

I am getting: "No etherbase set and no accounts found as default" when trying to sync my node using: geth --testnet --rpc --rpcapi db,eth,net,web3,personal --cache=1024 --rpcport 8545 --rpcaddr 127....
0
votes
1answer
227 views

Not getting any results from Web3j querying of ERC20 token's balanceOf() function

I am trying to use Web3j to query the balanceOf() function of a standard ERC20 token as shown in the code below: try { String encodedFunction = FunctionEncoder.encode(function); ...
0
votes
0answers
6 views

what configuration I need to set at parity if I using web3js?

What is the setting at Parity private server, if I want to sent signed transaction? const sender = '0x...'; const senderPrivateKey = '...'; const recipient = '0x..'; const ...
0
votes
1answer
38 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
0
votes
2answers
88 views
3
votes
5answers
3k views

Can't get ether from Rinkeby testnet faucet

I'm a new user trying out the Rinkeby testnet. I followed the procedure in this youtube video. But I can't get ether. This page says "Invalid User... boom!" I've contacted GitHub. They suspect that ...
0
votes
1answer
31 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', ...
0
votes
0answers
4 views

How to save as g6 using graphs.nauty_geng in Sage?

I am trying to get Sage to generate all graphs with 7. I typed in the following: g7=[g for g in graphs.nauty_geng('7') ] I’d like to save as g6 data typeI file. How to do ? I want to use the g6 ...
0
votes
0answers
8 views

Is it normal that the last transactions don’t appear on Etherscan?

Last block with latest transaction was mined 4 hours ago. Of course, other explorers can see the latest ones but I need the Etherscan feature of accessing the details storage change of transactions. ...
0
votes
1answer
103 views

Ethereum mempool transaction of Uncle and Fork nodes

In the Bitcoin network when a fork happens, the block transactions from the shortest chain are reinserted again into the mempool. In Ethereum instead we have Uncle blocks and Fork blocks. What ...
0
votes
1answer
257 views

I tried to deploy a contract on Ropsten, but always get the following error

PS D:\nodejs\rff\metacoin> truffle --network ropsten migrate Using network 'ropsten'. Running migration: 1_initial_migration.js Deploying Migrations... Error encountered, bailing. Network state ...
0
votes
1answer
97 views

Unlocking account web3.js 1.0 on AWS Lambda

I'm getting following error message when trying to unlock account on AWS Lambda: Error: Node error: {"code":-32601,"message":"The method personal_unlockAccount does not exist/is not available"} ...
1
vote
1answer
188 views

running eth-net-intelligence-api throws “[eth] =✘= Web3 connection attempt #0 failed”

I am trying to run eth-netstart in my machine. I run geth using this command line: geth --datadir innofactory1/ --syncmode 'full' --port 30312 --rpc --ws --wsorigins "*" --rpccorsdomain '"*"' --...
0
votes
1answer
242 views

Web3.js event.get not firing, whereas event.watch gives correct values

I am trying to do a simple test for events. Following is solidity code. Values received from chgEvent.watch are always correct. But in chgEvent.get, results1 is empty. chgEvent.get does not get ...
4
votes
1answer
582 views

Extremely slow geth mining and synchronization for private blockchain

I am constructing a very simple 2 nodes private Ethereum network to study the mining behaviour. The consensus algorithm is ethash. In order for the 2 nodes to discover each other, I also setup a ...
1
vote
0answers
9 views

Creating a contract instance

Is it generally better to define a contract instance once, then pass it through your components like... class Parent extends React.Component{ constructor(props){ super(props); ...
0
votes
0answers
10 views

Function Call when Sender Must Be Certain Address

I have a contract on Ropsten, and when I do this is python, I get a result: result = contract.functions.getLastUpdateTime(0).call() So I know the abi is there, the address, etc. There's another ...
0
votes
1answer
102 views

Web3js can not touch smart contract, always return 0

web3js can not touch smart contract. var id = dragoncore.getGenesNum(); has no error, but always return back 0, never changed. -----------------------------web3js code ----------------------------- ...
0
votes
1answer
125 views

Mist : Getting error Couldn't connect to node? See the logs for more:

First I started the private network and connected with 2 node . After I opened another terminal and used the command to open the mist: open -a /Applications/Mist.app --args --rpc /usr/local/Cellar/...
0
votes
0answers
12 views

TypeError: market.FileViewed is not a function while trying to watch event

I want to watch for fileViewed event and it throws TypeError: market.FileViewed is not a function in marketplace.FileViewed{ ^ My solidity contract: pragma solidity ^0.5.0; contract ...
0
votes
0answers
7 views

How To Unit Test Smart Contracts With Inheritance & Modifiers

What is the best way to approach unit testing of smart contracts which inherit other contracts, and use custom modifiers? Here's an example of a simple Whitelisting smart contract which implements ...
0
votes
2answers
152 views

Cryptocurrency Tutorial: how to transfer on the geth console?

I build, compiled and deployed (to Testrpc) the token contract from the cryptocurrency tutorial. The token offers the transfer(addres _to, uint256 value) method, which I would like to call from ...
1
vote
0answers
6 views

How to tell if `geth` connected to EVM One?

I'm using the EVM One back-end with ewasm/geth according to the following instructions. Geth seems to be starting up as usual with the following command: geth --vm.evm=./libevmone.dylib How can I ...
0
votes
1answer
16 views

Link library to contract without migrations

To link library in migrations I use: await deployer.deploy(MyTokenL) await deployer.link(MyTokenL, MyToken) We want to use migrations as infrastructure deployment and then have a deployment factory ...
2
votes
1answer
263 views

subscription not happen on geth+websocketProvider in web3

I have started geth node (connect to ropsten testnet) on my local OSX system. Command: geth --testnet --fast --bootnodes "enode://...
0
votes
1answer
6 views

How estimate GAS from a contract call with Web3j

I'm trying to estimate gas cost of a contract call, i need to send a string to a contract, but i need to see if i overtook the GAS limit. I'm trying like this: Transaction t = Transaction....
0
votes
1answer
165 views

Web3js :interact with smart contract

I'm currently struggling to interact with my smart contract, I don't if it comes from the way I call the function or the way I connect to my smart contract. Here is the code const contractAddress = '...
0
votes
0answers
13 views

cloning div container number of deployed child contracts time and put their data inside div container

Sorry for the silly question. I have a div container "product-card" , I want to loop the number of my deployed smart contracts time. every time when I loop I want to clone this div container and ...
0
votes
1answer
13 views

Giving a big nonce in transaction doesn't return anything?

When we put a low nonce in transaction options we got "nonce too low", but when a put a big nonce (bigger then transaction count) we got anything why ?
0
votes
1answer
16 views

Does etherum support smart contrast that has many subcontracts that can be executed once they are called by others

Can I have a main smart contrast that has many subcontracts that can be executed once they are called by other people? And the subcontracts can update the status of the main one if some conditions are ...
1
vote
3answers
294 views

Can't compile old solidity contracts(version 0.4.17)

I'm new with blockchain development. I'm working on an old project which use solidity 0.4.17 and truffle ^4.0.0-beta.2; These versions were in the package.json file of the project. When I installed ...
2
votes
0answers
11 views

Why is it required to know the function selector in a smart contract to call the function? [duplicate]

I understand what a function selector is and how it is computed: The first four bytes of the call data for a function call specifies the function to be called. It is the first (left, high-order ...
0
votes
1answer
22 views

How to change push() method to simple code?

I have this code but it's static and I wanna change it dynamically. function addCandidates(){ if( own == 1 ){ candidate[0].candidate_ID[0] = 1; candidate[0].candidate_ID[1] = 2; ...
4
votes
2answers
2k views

Is a smart contract analogous to an OOP class?

Can I think of a smart contract as being analogous to a Class in an object-oriented programming language (e.g., Java)? Each transaction that uses the contract essentially instantiates an object of ...
0
votes
0answers
8 views

How can I change the text message on connection request window of metamask?

I want to change the message in connection request window using web3js. I have attached screenshot here. kindly check it.
0
votes
0answers
5 views

hwo to identifie error from transaction error object?

is it possible to know what is the reason of transaction error from "error" object (nonce, insufficient fund ..) is there status or something to test using it ? Geth error message is generic, I ...
1
vote
2answers
26 views

How do i use .send() to fire methods of my smartcontract?

I have looked alot for information about this and lastly i turn myself to here. I've written a smartcontract and deployed it to Ropsten . I am then using web3.js to interact with my smartcontract, i ...

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