Most viewed questions in Blockchain

–1 vote
1 answer

Not able to create new account in geth for private ethereum blockchain

personal.newAccount() is not a default geth method. This ...READ MORE

Jan 17, 2019 in Blockchain by Omkar
• 69,210 points
3,394 views
0 votes
1 answer
0 votes
1 answer

How do I send back ethers to the sender of the tokens in a smart contract?

Whenever a smart contract receives ether via ...READ MORE

May 30, 2018 in Blockchain by Perry
• 17,100 points
3,371 views
+1 vote
1 answer

Getting issues while Sending signTransaction with web3.js

The chain ID for ropsten is 3. ...READ MORE

Mar 28, 2018 in Blockchain by Johnathon
• 9,090 points
3,333 views
0 votes
1 answer

How to save complex object in the contract in solidity

You can't pass objects when initiating a ...READ MORE

Oct 15, 2018 in Blockchain by Omkar
• 69,210 points
3,325 views
0 votes
1 answer

When running the enrollAdmin.js i get this error:

you are not running the ca, port ...READ MORE

Jun 7, 2020 in Blockchain by sumit
3,320 views
0 votes
1 answer

Hyperledger Fabric: How to get transaction history using key?

history, err := stub.GetHistoryForKey(key_value) for history.HasNext() { ...READ MORE

Nov 20, 2018 in Blockchain by Omkar
• 69,210 points
3,312 views
0 votes
1 answer

Generate Ethereum addresses in HD Wallet using public key only (bitcoinj/web3j)

Like Bitcoin, Ethereum uses secp256k1. Ethereum addresses ...READ MORE

Apr 12, 2022 in Blockchain by Soham
• 9,700 points
3,304 views
+1 vote
7 answers

What are the advantages and limitations of hyperledger composer over fabric?

While hyperledger composer is a set of ...READ MORE

Apr 8, 2018 in Blockchain by Perry
• 17,100 points
3,283 views
+1 vote
1 answer

geth: Fatal: Failed to read genesis file: open “/home/edureka/privatechain/”: no such file or directory

Use this: geth --datadir ./data init ./custom_genesis.json READ MORE

Dec 6, 2018 in Blockchain by Omkar
• 69,210 points
3,281 views
0 votes
1 answer

Why do the resultant hash after mining has a leading no. of zeroes in Blockchain verification?

This is chosen by the DIFFICULTY EQUATION. In ...READ MORE

Aug 10, 2018 in Blockchain by Christine
• 15,790 points
3,275 views
+1 vote
2 answers

Hyperledger: get “/bin/bash: ./scripts/script.sh: No such file or directory” when running “./byfn -m up”

You can follow these steps : In your ...READ MORE

Mar 27, 2018 in Blockchain by ned_crew
• 1,610 points
3,238 views
+1 vote
5 answers

Does Hyperledger remove asset actually remove anything?

Hyperledger remove asset doesn't actually "remove" the ...READ MORE

Jun 19, 2018 in Blockchain by charlie_brown
• 7,720 points
3,218 views
+2 votes
1 answer

how to convert hash160 to bitcoin address in python?

Hey @Raj. I use the following script. ...READ MORE

Jul 12, 2019 in Blockchain by Tanisha
3,212 views
0 votes
1 answer

var_dump of a JSON response returns NULL

You should be aware of the chances ...READ MORE

Aug 28, 2018 in Blockchain by digger
• 26,740 points
3,192 views
0 votes
1 answer

Cannot find package “google/protobuf”

Firstly, your import is wrong, you are ...READ MORE

Oct 1, 2018 in Blockchain by Perry
• 17,100 points
3,180 views
0 votes
1 answer

Stuck while using call_back_address and ipn url in coinpayment.net gateway

To make use of this api, just ...READ MORE

Aug 31, 2018 in Blockchain by digger
• 26,740 points
3,172 views
+1 vote
5 answers

Hyperledger Fabric: Error cryptogen tool

I got same error on Windows.  The solution ...READ MORE

Oct 25, 2018 in Blockchain by Mahesh
3,163 views
0 votes
0 answers
0 votes
1 answer

How can I become a miner in Blockchain?

You need to download software to become ...READ MORE

Jul 3, 2019 in Blockchain by Raman
3,162 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
3,162 views
0 votes
1 answer

String concatenation in solidity?

A library can be used, for example: import "github.com/Arachnid/solidity-stringutils/strings.sol"; contract C ...READ MORE

Sep 21, 2018 in Blockchain by slayer
• 29,350 points
3,146 views
0 votes
1 answer

How can I integrate ethereum wallet on my site??

you can use web3 js API to ...READ MORE

May 29, 2018 in Blockchain by Perry
• 17,100 points
3,146 views
0 votes
1 answer

How can i import the csv/excel files into my contract and record the transaction ?

You can not directly import an excel/csv ...READ MORE

Apr 16, 2019 in Blockchain by Omkar
• 69,210 points
3,122 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
3,113 views
0 votes
1 answer

javascript bytes32 to string

Assuming you're using web3 on the JS side, it's web3.toAscii. Example ...READ MORE

Oct 8, 2018 in Blockchain by Omkar
• 69,210 points
3,110 views
0 votes
2 answers

Where can i find Hyperledger Fabric Node SDK sample application?

Here are some links where you can ...READ MORE

Apr 26, 2019 in Blockchain by Firoz
3,107 views
0 votes
1 answer

TypeError: argument must be a string node.js while encoding to hex string.

The error is in protobuf.Transaction.create headerSignature needs to be a string, ...READ MORE

Nov 6, 2018 in Blockchain by Omkar
• 69,210 points
3,094 views
+1 vote
2 answers

Peer chaincode instantiation timeout expired

Hey, i think you made a slight ...READ MORE

Sep 19, 2018 in Blockchain by digger
• 26,740 points
3,086 views
+6 votes
3 answers

Why don't we consider Git as a Blockchain?

Blockchain is not just any chain of any blocks. Blockchain is when there ...READ MORE

Sep 7, 2018 in Blockchain by Rowski
3,086 views
+1 vote
3 answers

How efficient is Ethereum in regard to its TPS??

TPS means transactions processing at any given ...READ MORE

Apr 16, 2018 in Blockchain by Shashank
• 10,400 points
3,085 views
0 votes
1 answer

How to generate new address for blockchain wallet?

You can use the following to generate ...READ MORE

Jul 16, 2018 in Blockchain by digger
• 26,740 points
3,073 views
0 votes
2 answers

Using Hyperledger composer with Hyperledger Blockchain explorer.

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

Aug 9, 2018 in Blockchain by digger
• 26,740 points
3,070 views
+1 vote
4 answers

Trying to connect to Cryptocompare's websocket stream using socketIO from a Python client

The reason might be that the the socketio ...READ MORE

Aug 6, 2018 in Blockchain by Perry
• 17,100 points
3,048 views
0 votes
2 answers

Hyperledger byfn: could not assemble transaction: ProposalResponsePayloads do not match

This is because you have not installed ...READ MORE

Nov 20, 2018 in Blockchain by Omkar
• 69,210 points
3,033 views
+1 vote
2 answers

Can I invoke a chaincode function from the chaincode itself?

Here's an example on how you can ...READ MORE

May 7, 2019 in Blockchain by Shir
3,031 views
0 votes
1 answer

How do display all the events logs from a smart contract?

You'll need to watch the events. const filter ...READ MORE

Oct 3, 2018 in Blockchain by digger
• 26,740 points
3,005 views
0 votes
1 answer

Bitcoin: parsing Blockchain API using JSON

Because you only add one address to ...READ MORE

Aug 22, 2018 in Blockchain by digger
• 26,740 points
2,992 views
0 votes
2 answers

Hyperledger Fabric: Channel creation failed! FAILED to execute End-2-End Scenario

This error usually occurs if some old ...READ MORE

May 8, 2019 in Blockchain by John
2,989 views
0 votes
2 answers

How to check if bitcoin address is valid?

For Java, have a look at the ...READ MORE

Aug 20, 2018 in Blockchain by Omkar
• 69,210 points
2,973 views
0 votes
3 answers

String conversion to Array in Solidity

There is no built-in method/function for this ...READ MORE

Oct 3, 2018 in Blockchain by Charlie
2,971 views
0 votes
1 answer

How to install Ethereum on Windows?

Download geth installer from https://geth.ethereum.org/downloads/ After download, run ...READ MORE

Feb 28, 2019 in Blockchain by Raj
2,970 views
0 votes
1 answer

Error while sending an address to functions

In solidity 0.5.0 (and above) there are ...READ MORE

Jan 23, 2019 in Blockchain by Omkar
• 69,210 points
2,948 views
0 votes
2 answers

Web socket API session automatically disconnecting

Yes, the code given by Christine works! ...READ MORE

Aug 29, 2018 in Blockchain by digger
• 26,740 points
2,924 views
+1 vote
4 answers

What is the asset, key-value pair in hyperledger fabric?

Let me explain with an example. Suppose ...READ MORE

May 2, 2019 in Blockchain by Kiran
2,923 views
0 votes
1 answer

HyperLedger Fabric and Multichain - difference & different use cases

MULTICHAIN: It is a Permissioned Blockchain. It doesn't implement ...READ MORE

Dec 28, 2018 in Blockchain by Omkar
• 69,210 points
2,919 views
+1 vote
2 answers

How to configure Endorsement policy in Hyperledger?

The Hyperledger Fabric Endorsement policy is configured ...READ MORE

Jul 25, 2018 in Blockchain by slayer
• 29,350 points
2,917 views
+1 vote
3 answers

Hyperledger Java SDK Client Event Listener to register and listen Blocks

First add the eventhub, and then  register ...READ MORE

Oct 29, 2018 in Blockchain by Omkar
• 69,210 points
2,915 views
0 votes
1 answer

Can't call contract function in truffle console

Inspect the object adoption within the console. You will ...READ MORE

Sep 28, 2018 in Blockchain by slayer
• 29,350 points
2,914 views
0 votes
1 answer

Solidity invalid opcode error

In the for loop, your indexing going ...READ MORE

Aug 16, 2018 in Blockchain by slayer
• 29,350 points
2,911 views