Trending questions in Blockchain

+1 vote
3 answers

HTML Bitcoin address parsing using Beautiful soup

Regex is not meant for parsing. As ...READ MORE

Sep 5, 2018 in Blockchain by Lewis
1,336 views
0 votes
1 answer

How to access bitcoin Daemon from other services?

You don't need all these things to ...READ MORE

Aug 29, 2018 in Blockchain by digger
• 26,740 points
1,756 views
0 votes
1 answer

blockchain/service-my-wallet-v3 - Connection refused

Hey, if you have installed blockchain/service-my-wallet properly, ...READ MORE

Sep 18, 2018 in Blockchain by slayer
• 29,350 points
886 views
0 votes
1 answer

Python Double hash SHA256

You can get the given hash by ...READ MORE

Aug 29, 2018 in Blockchain by slayer
• 29,350 points
1,723 views
0 votes
1 answer

How to generate litecoin using pycoin?

In the secret_exponent_to_wif function def secret_exponent_to_wif(se, compressed): ...READ MORE

Aug 29, 2018 in Blockchain by digger
• 26,740 points
1,713 views
0 votes
1 answer

Using Bitcoin's sendmany function with perl

Replace the line  my $action = $api->call('sendmany','',%recipients); with  my ...READ MORE

Sep 11, 2018 in Blockchain by digger
• 26,740 points
1,145 views
0 votes
1 answer

Getting error during “truffle migrate” for an ethereum contract on testrpc

Can you just try to give network ...READ MORE

Sep 27, 2018 in Blockchain by slayer
• 29,350 points
450 views
0 votes
1 answer

“make” build ‘EC_GF2m_simple_method’ was not declared in this scope error in centos7

Step 1: I assume that your present ...READ MORE

Sep 17, 2018 in Blockchain by digger
• 26,740 points
867 views
0 votes
1 answer

Php code to generate Ethereum wallets.

You can use web3.eth.accounts in web3js web3.eth.accounts.create(); With Php, ...READ MORE

Jul 27, 2018 in Blockchain by slayer
• 29,350 points
3,105 views
0 votes
2 answers

Does Ethereum Solidity support Associative Arrays?

Here's a little example that passes values ...READ MORE

Sep 17, 2018 in Blockchain by Bobin
877 views
0 votes
1 answer

Can we set a list of discovery nodes in Hyperledger fabric?

New nodes doesn't depend on a single ...READ MORE

Sep 19, 2018 in Blockchain by Christine
• 15,790 points
759 views
0 votes
1 answer

What do I import for SHA encryption in Node.js?

var sha = require('sha.js'); //... getHash() { ...READ MORE

Sep 21, 2018 in Blockchain by digger
• 26,740 points
665 views
0 votes
1 answer

Bitcoin Wallet address validation using Json and bitcoin/blockexplorer.

The URL isn't returning JSON. So instead ...READ MORE

Aug 20, 2018 in Blockchain by slayer
• 29,350 points
2,030 views
0 votes
1 answer

ERRO : Error trying to connect to local peer: grpc: timed out trying to connect

You need to use the correct port ...READ MORE

Sep 17, 2018 in Blockchain by slayer
• 29,350 points
813 views
0 votes
1 answer

How connect library to smart contract from external resources?

pragma solidity ^0.4.0; import "github.com/OpenZeppelin/zeppelin-solidity/contracts/math/SafeMath.sol"; contract MathExtended { ...READ MORE

Sep 26, 2018 in Blockchain by digger
• 26,740 points
414 views
0 votes
1 answer

Nodejs: How to pass user form data into defined class

This should do your work: // select the ...READ MORE

Sep 19, 2018 in Blockchain by digger
• 26,740 points
711 views
0 votes
1 answer

Not able to send Ethereum transaction

Hey, Change this line: await crowdsale.sendTransaction({value, from: buyer, gas: ...READ MORE

Sep 24, 2018 in Blockchain by slayer
• 29,350 points
494 views
0 votes
1 answer

How are the ethers sent to smart contract in the IBM example?

They are in magical variable msg. The function ...READ MORE

Sep 28, 2018 in Blockchain by digger
• 26,740 points
317 views
0 votes
1 answer

'Invalid sender' error after upgrading to geth 1.4.0

Guessing that the JSON RPC stuff changed ...READ MORE

Sep 11, 2018 in Blockchain by Christine
• 15,790 points
1,042 views
0 votes
1 answer

How to extend Composer rest Server ?

 It looks like you want to query ...READ MORE

Sep 20, 2018 in Blockchain by Perry
• 17,100 points
650 views
0 votes
1 answer

Etheruem: Pyethereum Error

Try running this: sudo easy_install -U setuptools In my ...READ MORE

Sep 28, 2018 in Blockchain by digger
• 26,740 points
300 views
0 votes
1 answer

How to interact with a Smart Contract on private network using Web3.js?

Once you set up infura you can ...READ MORE

Aug 22, 2018 in Blockchain by Christine
• 15,790 points
1,901 views
0 votes
2 answers

Issues while installing Hyperledger Composer

Follow these steps to correctly install: mkdir ~/fabric-dev-servers ...READ MORE

Nov 15, 2018 in Blockchain by Omkar
• 69,210 points
781 views
0 votes
1 answer

What does _ mean in solidity language?

The _ symbol is a place holder. ...READ MORE

Aug 10, 2018 in Blockchain by digger
• 26,740 points
2,367 views
0 votes
1 answer

how loop through a JSON Array of bitcoin transaction data

for($i=0; $i<count($result['out']); $i++) { echo ...READ MORE

Sep 21, 2018 in Blockchain by slayer
• 29,350 points
536 views
+2 votes
1 answer

What is Bitcoin Powered Electrical Outlet?

Bitcoin powered electrical outlet is nothing but ...READ MORE

Sep 20, 2018 in Blockchain by Bhaskar
491 views
0 votes
1 answer

How do you obtain the transaction uuid after submitting an invoke transaction using the nodejs HFC

The results returned via the 'submitted' event ...READ MORE

Sep 14, 2018 in Blockchain by slayer
• 29,350 points
837 views
0 votes
1 answer

Bitcoinjs-lib getAddress not a function error

You need to pass network parameter to ...READ MORE

Aug 27, 2018 in Blockchain by slayer
• 29,350 points
1,604 views
+1 vote
1 answer

Ethereum vs Hyperledger: Which is better for business networks?

Hyperledger is preferred for B2B business and ...READ MORE

Sep 20, 2018 in Blockchain by digger
• 26,740 points
516 views
0 votes
1 answer

What Regex to use to identify a Block Hash?

Blockhashes are always 64 characters in length. You ...READ MORE

Aug 28, 2018 in Blockchain by digger
• 26,740 points
1,551 views
0 votes
1 answer

pybitcointools pushtx TypeError: expected string or buffer

From the looks of it, you need ...READ MORE

Sep 6, 2018 in Blockchain by digger
• 26,740 points
1,160 views
+1 vote
1 answer

Is there a way to send funds from a specific bitcoin address in a wallet?

I'll answer my own question, It was unbelievably ...READ MORE

Sep 3, 2018 in Blockchain by Perry
• 17,100 points
1,243 views
0 votes
1 answer

Why do people prefer mining Litecoin over Bitcoin?

The main reason people prefer mining Litecoin ...READ MORE

Sep 21, 2018 in Blockchain by slayer
• 29,350 points
505 views
0 votes
1 answer

How to create raw transaction using web3swift?

var options = Web3Options.defaultOptions() options.gasLimit = BigUInt(21000) options.from = ...READ MORE

Sep 17, 2018 in Blockchain by slayer
• 29,350 points
676 views
0 votes
1 answer

PHP Bitcoin validate from form

isValid($addr, $version) $addr: A bitcoin address $version: The ...READ MORE

Sep 3, 2018 in Blockchain by slayer
• 29,350 points
1,275 views
0 votes
1 answer

How to handle Overlapping of array objects in node js

Try this code, may be it works for ...READ MORE

Sep 18, 2018 in Blockchain by digger
• 26,740 points
614 views
0 votes
1 answer

How to deploy hyperledger fabric in production level?

Once you set up the Fabric, bring ...READ MORE

Aug 2, 2018 in Blockchain by aryya
• 7,450 points
2,668 views
0 votes
1 answer

How to send JSON object from npm module to browser

A simple solution for this would be ...READ MORE

Sep 20, 2018 in Blockchain by digger
• 26,740 points
521 views
+1 vote
1 answer

Unable to convert variable to GMP when initializing Bitpay client class (Laravel)

Bitpay automatically uses the encrypted file store, ...READ MORE

Sep 10, 2018 in Blockchain by slayer
• 29,350 points
914 views
0 votes
1 answer

Is there a way to get a trade history report from the Bitfinex API?

You can still fetch your private trades ...READ MORE

Aug 30, 2018 in Blockchain by Perry
• 17,100 points
1,450 views
0 votes
1 answer

Decorators in Hyperledger Composer Modeling Language

Define you CustomAsset like mentioned below and ...READ MORE

Sep 19, 2018 in Blockchain by slayer
• 29,350 points
557 views
0 votes
1 answer

Not able to run chaincode locally using docker

Looks like the Fabric team introduced "nopkcs11" ...READ MORE

Sep 18, 2018 in Blockchain by slayer
• 29,350 points
589 views
0 votes
2 answers

PHP: json_decode - reading category names

<?php function findHighestBid() { $result = ...READ MORE

Sep 7, 2018 in Blockchain by Shotgun
1,021 views
+1 vote
1 answer

Node.js blockchain bitcoin api

The callback URL should be the one ...READ MORE

Sep 10, 2018 in Blockchain by slayer
• 29,350 points
893 views
+1 vote
1 answer

How to create participant and there identities via rest API in Hyperledger Composer?

If you have already imported an Identity ...READ MORE

Aug 10, 2018 in Blockchain by Perry
• 17,100 points
2,210 views
0 votes
1 answer

How to send Bitcoins with node.js?

This website https://blockr.io/tx/push will successfully do the ...READ MORE

Jul 20, 2018 in Blockchain by Christine
• 15,790 points
3,157 views
0 votes
1 answer

How to make POST request on C# to blockr.io

By default UploadValues doesn't format the data ...READ MORE

Aug 30, 2018 in Blockchain by digger
• 26,740 points
1,390 views
+2 votes
1 answer

How to store data in Hyperledger Fabric after restart?

When you use docker-compose down, all the ...READ MORE

Jul 27, 2018 in Blockchain by digger
• 26,740 points
2,773 views
0 votes
1 answer

coin.mx : 403 forbidden error on my web request

I was having the same issue and ...READ MORE

Sep 11, 2018 in Blockchain by digger
• 26,740 points
865 views
+1 vote
2 answers

Hex to ASCII conversion shows wrong result.

Hey, I use the following code: public static ...READ MORE

Aug 21, 2018 in Blockchain by Omkar
• 69,210 points
1,689 views