Trending questions in Blockchain

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How to choose which function is called first in Node Js

You can do something like: infuraProvider.getBlockNumber().then(function(blockNumber) { ...READ MORE

Oct 8, 2018 in Blockchain by Omkar
• 69,180 points
816 views
0 votes
1 answer

How to call function in one contract from another contract in private blockchain?

Please check whether you have byzantiumBlock: 0 in your ...READ MORE

Oct 1, 2018 in Blockchain by digger
• 26,740 points
1,106 views
0 votes
1 answer

Can't install pyethereum module

The module's name is ethereum, not pyethereum. Using the ...READ MORE

Sep 27, 2018 in Blockchain by slayer
• 29,370 points
1,260 views
0 votes
1 answer

How to connect to *coin RPC-Server with PHP

If you want to connect inside your ...READ MORE

Sep 12, 2018 in Blockchain by slayer
• 29,370 points
1,906 views
+1 vote
1 answer

Deploy contract using solcjs

Try to add some typo and run ...READ MORE

Sep 26, 2018 in Blockchain by slayer
• 29,370 points
1,258 views
0 votes
1 answer

Unable to unmarshal non-string into Go struct field SendTxArgs from of common.Address

Probably you should specify the default_account for client(sender address). In my ...READ MORE

Aug 28, 2018 in Blockchain by Johnathon
• 9,090 points
2,571 views
0 votes
1 answer

Corda: uploading a file, attach and download

Hey, i found an example that i ...READ MORE

Sep 19, 2018 in Blockchain by digger
• 26,740 points
1,586 views
0 votes
1 answer

Can't send transaction even if I use an example from official Ethereum webpage

As I understand your question you are ...READ MORE

Sep 21, 2018 in Blockchain by slayer
• 29,370 points
1,488 views
0 votes
1 answer

How to create an asset on Bigchaindb server using http call

You could start like this: method = POST URL ...READ MORE

Sep 19, 2018 in Blockchain by Christine
• 15,750 points
1,564 views
0 votes
1 answer

How to register a user in Hyperledger Fabric?

Best practice would be to leverage an ...READ MORE

Sep 5, 2018 in Blockchain by Christine
• 15,750 points
2,167 views
0 votes
1 answer

Truffle migration error (test rpc is running)

1) Run the following command: npm install -g ...READ MORE

Oct 3, 2018 in Blockchain by slayer
• 29,370 points
955 views
0 votes
1 answer

Contract deployment is raising gas issue while transaction and issue vary on various networksbl

Starting time can't be in the past. new ...READ MORE

Oct 3, 2018 in Blockchain by Omkar
• 69,180 points
949 views
0 votes
1 answer

Nodejs Express: Getting different output in console.log and callback

If your getOrderStatus() function is like this: function getOrderStatus(_orderId, callback) ...READ MORE

Oct 9, 2018 in Blockchain by Omkar
• 69,180 points
684 views
+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
2,016 views
0 votes
1 answer

XMLHttpRequest is not defined while sending request to blockchain service via C#

use post data in url link and ...READ MORE

Sep 20, 2018 in Blockchain by slayer
• 29,370 points
1,476 views
0 votes
1 answer

Testrpc Error: listen EADDRINUSE :::8545 on Mac

Another process is already using the port ...READ MORE

Sep 26, 2018 in Blockchain by digger
• 26,740 points
1,218 views
0 votes
1 answer

Why Gas Used By Txn is different when invoking the same function in the same smart contract?

The input data might be different, but ...READ MORE

Sep 25, 2018 in Blockchain by Christine
• 15,750 points
1,276 views
0 votes
1 answer

Store contract results tag in a variable

then() takes a function as argument that is ...READ MORE

Oct 9, 2018 in Blockchain by Omkar
• 69,180 points
626 views
0 votes
1 answer

Repeating transactions hangs - web3js, local geth

If you are sending transactions back-to-back from ...READ MORE

Sep 24, 2018 in Blockchain by digger
• 26,740 points
1,264 views
0 votes
1 answer

How to achieve simple OOP in Solidity?

contract A { uint public ...READ MORE

Sep 27, 2018 in Blockchain by slayer
• 29,370 points
1,123 views
0 votes
1 answer

How to run Meteor insert within a Fiber?

Just replace events.watch(function(error, event) { ... }); with events.watch(Meteor.bindEnvironment(function(error, event) ...READ MORE

Sep 28, 2018 in Blockchain by slayer
• 29,370 points
1,056 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
1,528 views
0 votes
1 answer

How do I compile a piece of Solidity Code using eris' javascript?

The easiest way to compile Solidity is ...READ MORE

Sep 27, 2018 in Blockchain by digger
• 26,740 points
1,096 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
• 29,370 points
2,432 views
0 votes
1 answer

Unable to enroll user in new org

The thing is by default, fabric-ca only has ...READ MORE

Aug 25, 2018 in Blockchain by Christine
• 15,750 points
2,542 views
0 votes
1 answer

How to round a number down to 8 decimal places if its over 8 decimal places in Javascript

Try it in this way: function nrOfDecimals(number) { ...READ MORE

Sep 12, 2018 in Blockchain by slayer
• 29,370 points
1,732 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
• 29,370 points
3,757 views
+3 votes
1 answer

What is the difference between online and offline hyperledger composer?

Hey @Renu353! Well, it's good that you ...READ MORE

Sep 21, 2018 in Blockchain by Omkar
• 69,180 points
1,194 views
0 votes
1 answer

Web3j: Writing operations on a contract always throw “java.lang.ArrayIndexOutOfBoundsException”

That exception is thrown when you pass ...READ MORE

Oct 1, 2018 in Blockchain by slayer
• 29,370 points
873 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
• 29,370 points
2,684 views
0 votes
1 answer

Solidity, javascript Wrong format: invalid address

The contract lacks initialization, at first. var contract ...READ MORE

Sep 17, 2018 in Blockchain by digger
• 26,740 points
1,474 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
• 7,460 points
3,483 views
0 votes
1 answer

Web3 1.0: What does `web3.eth.call(tx)` return for a contract creation?

The returned bytestring is the deployedBytecode of the contract, ...READ MORE

Sep 17, 2018 in Blockchain by digger
• 26,740 points
1,456 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
3,605 views
0 votes
2 answers

Truffle migrate Error after run testrpc

Simple Solution: // module.exports = { // ...READ MORE

Sep 24, 2018 in Blockchain by Wasim
1,084 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
3,064 views
0 votes
1 answer

Getting wrong result from SHA256 than what is expected

It's just an encoding issue - don't ...READ MORE

Sep 6, 2018 in Blockchain by digger
• 26,740 points
1,894 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
1,676 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
1,441 views
0 votes
1 answer

Access variables through auto-generated getters from a different contract

You just need to pass it in ...READ MORE

Oct 3, 2018 in Blockchain by slayer
• 29,370 points
719 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
• 69,180 points
1,430 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
• 29,370 points
2,212 views
0 votes
1 answer

How to solve “The method personal_newAccount does not exist/is not available” Error?

You are connecting using WS but have ...READ MORE

Jul 27, 2018 in Blockchain by slayer
• 29,370 points
3,637 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
2,204 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
• 15,750 points
2,534 views
0 votes
1 answer

ethminer failed to submit hashrate

The pool you are linking with the -F flag ...READ MORE

Sep 24, 2018 in Blockchain by digger
• 26,740 points
1,066 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
2,224 views
0 votes
1 answer

Sawtooth Javascript SDK "Batchlist rejected" error

What you can do is use intkey-client to the ...READ MORE

Sep 19, 2018 in Blockchain by digger
• 26,740 points
1,264 views
0 votes
2 answers

How to read CGMiner output?

the only thing that made it work ...READ MORE

Sep 17, 2018 in Blockchain by Ruby
1,410 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
• 29,370 points
1,259 views