Trending questions in Blockchain

+3 votes
3 answers

How to validate bitcoin address?

I found these 2 scripts online: Javascript: <html> <head> <script type="text/javascript" ...READ MORE

Aug 17, 2018 in Blockchain by slayer
• 29,370 points
6,436 views
0 votes
1 answer

ethereum eth_sendTransaction via PHP curl

Your params field is missing a wrapping array. Try ...READ MORE

Sep 27, 2018 in Blockchain by slayer
• 29,370 points
4,903 views
+1 vote
1 answer

Hyperledger fabric java sdk setup

Suppose (assuming) you started the first network ...READ MORE

Nov 17, 2018 in Blockchain by Christine
• 15,790 points
2,679 views
0 votes
2 answers

Hyperledger Fabric: invokeChaincode returns [Object object]

Replace  return shim.success(valString); with: return shim ...READ MORE

Nov 9, 2018 in Blockchain by Omkar
• 69,220 points
1,023 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
3,454 views
0 votes
1 answer

How to create a contract in truffle?

The command you are using to create ...READ MORE

Dec 11, 2018 in Blockchain by Omkar
• 69,220 points
1,587 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
3,682 views
0 votes
1 answer

Hyperledger — how to set up REST API for invoking Chaincode?

Hyperledger Fabric v1.0 and later does not ...READ MORE

Nov 17, 2018 in Blockchain by Christine
• 15,790 points
2,611 views
+3 votes
4 answers

How to solve “ERROR: manifest for hyperledger/fabric-orderer:latest not found” error?

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

Sep 6, 2018 in Blockchain by Rakesh
6,240 views
0 votes
1 answer

Ethereum contract hangs on AWS

Please check the memory consumption for docker ...READ MORE

Dec 31, 2018 in Blockchain by Omkar
• 69,220 points
662 views
0 votes
1 answer

When I create public getters (committed code), my contract exceeds code size limit

Are you pushing info one by one ...READ MORE

Dec 31, 2018 in Blockchain by Omkar
• 69,220 points
644 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
3,652 views
0 votes
1 answer

Not able to pull any events in ethereum

You need to catch the even emitted ...READ MORE

Dec 31, 2018 in Blockchain by Omkar
• 69,220 points
603 views
0 votes
1 answer

Not able to install Multichain

Hi. It seems you have changed some ...READ MORE

Dec 28, 2018 in Blockchain by Omkar
• 69,220 points
726 views
0 votes
1 answer

Hyper Fabric: Error: CONNECTION_FAILED. Description: dialing connection timed out

The mapping is not set up right. ...READ MORE

Nov 9, 2018 in Blockchain by Omkar
• 69,220 points
2,829 views
0 votes
1 answer

What is the difference between hashing and encryption process?

Hashing and encryption are same but not ...READ MORE

Dec 4, 2018 in Blockchain by Omkar
• 69,220 points
1,759 views
–1 vote
1 answer

Unable to create account in geth

Well, that's not how you create a ...READ MORE

Dec 28, 2018 in Blockchain by Omkar
• 69,220 points
707 views
0 votes
2 answers

Not able to POST chaincode to hyperledger-fabric using API

TypeError: Cannot read property 'curve' of undefined     at ...READ MORE

Jan 30, 2019 in Blockchain by SHRADDHA
1,019 views
0 votes
1 answer

Send all Tokens and Eth to a Address automatically

require(token.transfer(beneficiary, token.balanceOf(this))); where token is the ERC20 token you're transferring. ...READ MORE

Oct 1, 2018 in Blockchain by digger
• 26,740 points
4,263 views
0 votes
1 answer

truffle npm run dev not working

Are you running this command from the ...READ MORE

Dec 1, 2018 in Blockchain by Omkar
• 69,220 points
1,616 views
0 votes
1 answer

Hyperledger Fabric :failed to send proposal to peers: Unable to resolve host peer0.org1

This peer address does not exist on ...READ MORE

Nov 16, 2018 in Blockchain by Omkar
• 69,220 points
2,225 views
0 votes
1 answer

Hyperledger Fabric:Promise is rejected:Error:Failed to deserialize creator identity,The supplied identity is not valid.

 This error happens because basic-network/docker-compose.yaml has CA ...READ MORE

Nov 14, 2018 in Blockchain by Omkar
• 69,220 points
2,275 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
• 69,220 points
3,563 views
0 votes
1 answer

truffle create contract shows no network available error

In your truffle project directory, you have ...READ MORE

Dec 11, 2018 in Blockchain by Omkar
• 69,220 points
1,067 views
0 votes
1 answer

Hyperledger Fabric: Upgrading Chaincode after modification

You need to specify the channel name ...READ MORE

Nov 13, 2018 in Blockchain by Omkar
• 69,220 points
2,270 views
0 votes
2 answers

Hyperledger sawtooth installation: No connectivity between host computer and docker container

Check the ip used by docker. If ...READ MORE

Jan 21, 2019 in Blockchain by Bhavana
1,929 views
0 votes
1 answer

Where is the cryptogen tool in fabric?

Go in the fabric directory and then ...READ MORE

Oct 29, 2018 in Blockchain by Omkar
• 69,220 points
2,897 views
0 votes
1 answer

Angular: How to display ngModel Object In Html Template?

You can use pipe as json on html page like this: {{ ...READ MORE

Oct 30, 2018 in Blockchain by Omkar
• 69,220 points
2,842 views
0 votes
1 answer

What is my chaincode ID in Hyperledger Fabric?

Hey. You have used chaincode id but ...READ MORE

Nov 21, 2018 in Blockchain by Omkar
• 69,220 points
1,868 views
0 votes
2 answers

Laravel 5.4 to get data form API response

Input::get('var_name') READ MORE

Feb 14, 2019 in Blockchain by anonymous
1,838 views
0 votes
2 answers

Is it possible to modify a variable value from another contract?

No, you can't directly edit a variable ...READ MORE

Sep 24, 2018 in Blockchain by Sai
4,314 views
0 votes
1 answer

Invalid opcode error in a simple Solidity contract and script

You don't need to call .at() if you're using .new(). ...READ MORE

Sep 14, 2018 in Blockchain by slayer
• 29,370 points
4,776 views
0 votes
1 answer

Hyperledger Composer: Error: Error trying to start business network. Error: No valid responses from any peers.

You have to configure TLS in peers ...READ MORE

Nov 5, 2018 in Blockchain by Omkar
• 69,220 points
2,499 views
0 votes
2 answers

How to generate ethereum qr code address with amount?

You implement this package: ethereum-qr-code. It implements the EIP67 standard which uses ...READ MORE

Sep 6, 2018 in Blockchain by Omkar
• 69,220 points
5,059 views
0 votes
1 answer

How to use different network cards for multiple composer rest server users?

You are getting the same network card in ...READ MORE

Dec 6, 2018 in Blockchain by Perry
• 17,100 points
1,191 views
0 votes
1 answer

Why do I require fabric-kafka and fabric-order containers in same network?

There are three ordering services, as you ...READ MORE

Dec 6, 2018 in Blockchain by Perry
• 17,100 points
1,172 views
0 votes
1 answer

How can I get the same return value as solidity `abi.encodePacked` in Golang?

This is what I used:  package main import ( ...READ MORE

Sep 26, 2018 in Blockchain by slayer
• 29,370 points
4,208 views
+1 vote
4 answers

What role does Orderer peer serves in Hyperledger Fabric??

Shared communication channel to clients and peers ...READ MORE

Apr 12, 2018 in Blockchain by Johnathon
• 9,090 points
2,985 views
0 votes
1 answer

Not able to create contracts in truffle

It seems like you have files missing that ...READ MORE

Dec 11, 2018 in Blockchain by Omkar
• 69,220 points
861 views
0 votes
1 answer

NPM cannot install “truffle” on Windows

Your install is failing at node-gyp rebuild. Solutions ...READ MORE

Sep 27, 2018 in Blockchain by slayer
• 29,370 points
4,111 views
0 votes
1 answer

Hyperledger Fabric: How to access transaction ID in invoke function?

You can access transaction ID in Invoke ...READ MORE

Nov 5, 2018 in Blockchain by Omkar
• 69,220 points
2,397 views
0 votes
1 answer

Hyperldger: Hyperledger Explorer not starting. Throws error

in "network-config" you should use lowercase 'org1' { ...READ MORE

Nov 8, 2018 in Blockchain by Omkar
• 69,220 points
2,276 views
0 votes
1 answer

How to create Bitcoin Address in PHP?

You need to understand that Bitcoin address and ...READ MORE

Aug 28, 2018 in Blockchain by Perry
• 17,100 points
5,407 views
0 votes
1 answer

Not able to migrate truffle project even after running testrpc

Maybe you forgot to compile the project ...READ MORE

Dec 11, 2018 in Blockchain by Omkar
• 69,220 points
815 views
0 votes
1 answer

Ethereum truffle server command not working

Try this command to create project: truffle init ...READ MORE

Nov 30, 2018 in Blockchain by Omkar
• 69,220 points
1,291 views
+2 votes
3 answers

Can multi-channels be supported by Hyperledger in one peer?

Yes you can run  multiple chains on ...READ MORE

Apr 11, 2018 in Blockchain by Perry
• 17,100 points
2,843 views
0 votes
1 answer
+1 vote
1 answer

Calling deployed smart contract from node.js

contractInstance.wakeUp.call is calling the function as constant, but ...READ MORE

Sep 26, 2018 in Blockchain by digger
• 26,740 points
3,958 views
0 votes
1 answer

Cant set Remix IDE to work on testrpc

As I can see that you are ...READ MORE

Dec 11, 2018 in Blockchain by Omkar
• 69,220 points
694 views
0 votes
1 answer

Hyperledger Docker: Error building images: cannot connect to Docker endpoint.

Check your container environment variable: CORE_VM_ENDPOINT=unix:///var/run/docker.sock Then if you ...READ MORE

Nov 15, 2018 in Blockchain by Omkar
• 69,220 points
1,811 views