Most viewed questions in Blockchain

0 votes
1 answer

How to get return value from solidity contract?

Once you call a constant function, you ...READ MORE

Aug 16, 2018 in Blockchain by slayer
• 29,370 points
5,028 views
+15 votes
5 answers

How to add Org or peer in Org dynamically in Hyperledger fabric?

I know it is a bit late ...READ MORE

Jul 27, 2018 in Blockchain by Omkar
• 69,220 points

edited Jul 22, 2019 by Omkar 4,953 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
4,921 views
0 votes
1 answer

How to install truffle on Linux?

You can install Truffle using npm(node package manager). ...READ MORE

Feb 28, 2019 in Blockchain by Rishab
4,910 views
0 votes
1 answer

Truffle can not find artifacts error

To deploy any project/ smart contract, you ...READ MORE

Jan 24, 2019 in Blockchain by Omkar
• 69,220 points
4,897 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
4,805 views
+1 vote
2 answers

Using Composite Key formation to get states for a date range in Hyperledger Fabric V1.0

I think you have found a partial ...READ MORE

Jul 20, 2018 in Blockchain by charlie_brown
• 7,720 points
4,784 views
0 votes
1 answer

Cant decode hex sting into decimal. Getting TypeError.

On the line where it shows error, ...READ MORE

Jul 6, 2018 in Blockchain by slayer
• 29,370 points
4,771 views
0 votes
3 answers

Solidity: TypeError: Data location must be "memory" for parameter in function, but none was given.

Could be a version problem. This worked ...READ MORE

May 1, 2019 in Blockchain by Yogi
4,673 views
+1 vote
2 answers

How to solve Hyperledger Fabric "error endorsing chaincode" error?

Try to install chaincode with a name ...READ MORE

Jul 13, 2018 in Blockchain by digger
• 26,740 points
4,648 views
+2 votes
3 answers

Hyperledger Fabric: How to run node js chaincode in dev mode?

Hi, the command you are using to ...READ MORE

Nov 2, 2018 in Blockchain by Omkar
• 69,220 points
4,616 views
0 votes
2 answers

Why is network already up to date while trying to deploy a contract on truffle?

I guess you have ganache running already ...READ MORE

Apr 24, 2018 in Blockchain by Shashank
• 10,400 points
4,556 views
0 votes
1 answer

Javascript Websocket subscribe to channel

This is how you can do it let ...READ MORE

Aug 28, 2018 in Blockchain by slayer
• 29,370 points
4,519 views
+1 vote
2 answers

HyperLedger Fabric Java SDK - Wrinting the ChainCode Sample in Java

To get started developing Java chaincode Ensure you ...READ MORE

Aug 3, 2018 in Blockchain by Omkar
• 69,220 points
4,487 views
+1 vote
1 answer

Security Properties of Hash Functions

The difference is indeed subtle. I understood ...READ MORE

Mar 27, 2018 in Blockchain by Johnathon
• 9,090 points
4,444 views
0 votes
1 answer

Not able to install truffle using npm install -g truffle

You need root access to install truffle, ...READ MORE

Nov 29, 2018 in Blockchain by Omkar
• 69,220 points
4,425 views
+1 vote
2 answers

Error 500: mychannel has been migrated to new lifecycle. Chaincode instantiation error.

This error occured only because I had ...READ MORE

Jan 9, 2020 in Blockchain by Aditya
• 250 points
4,398 views
0 votes
3 answers

Hyperledger fabric: Cant connect peer to channel

Open the hosts file: $ gedit /etc/hosts And add the IP ...READ MORE

May 8, 2019 in Blockchain by John
4,372 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
4,339 views
0 votes
1 answer

Hyperledger Fabric: can't load package: package github.com/hyperledger/fabric/core/chaincode/shim:

You can install various golang projects with ...READ MORE

Oct 30, 2018 in Blockchain by Omkar
• 69,220 points
4,323 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
4,280 views
0 votes
1 answer

"Migrations" -- Returned error: authentication needed: password or unlock.

By default, the accounts are locked and ...READ MORE

Jan 17, 2019 in Blockchain by Omkar
• 69,220 points
4,257 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
4,229 views
+1 vote
1 answer

What are the differences between the hyperledger and Blockchain?

To answer your first query.. Blockchain is ...READ MORE

Apr 5, 2018 in Blockchain by anonymous
4,194 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
4,123 views
+1 vote
4 answers

How can we search a block using transaction Id(TxID) or hash?

The most obvious use case would be ...READ MORE

Apr 10, 2018 in Blockchain by Johnathon
• 9,090 points
4,103 views
+1 vote
2 answers

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

Looks like the account you are trying ...READ MORE

Dec 6, 2018 in Blockchain by Omkar
• 69,220 points
4,087 views
0 votes
1 answer
0 votes
1 answer
0 votes
1 answer

Truffle "Migrations" ran out of gas error

This error is caused because the amount ...READ MORE

Jan 17, 2019 in Blockchain by Omkar
• 69,220 points
4,068 views
–1 vote
1 answer

Not able to install truffle

I know this is very frustrating, I ...READ MORE

Jan 17, 2019 in Blockchain by Omkar
• 69,220 points
4,048 views
0 votes
1 answer

Angular 4, typescript Assign interface property to variable

The first thing worth noting is that ...READ MORE

Aug 27, 2018 in Blockchain by slayer
• 29,370 points
4,041 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
3,989 views
+16 votes
4 answers

Why do only ADMIN users in Hyperledger Fabric have the permission to install query in chaincode?

It was already decided that installing chaincode ...READ MORE

Apr 3, 2018 in Blockchain by Perry
• 17,100 points
3,964 views
0 votes
1 answer

How to retrieve data from a block to a blockchain?

web3.eth.getTransaction(txHash) will returns transaction details like blockHash, transactionIndex, ...READ MORE

Jun 27, 2018 in Blockchain by Perry
• 17,100 points
3,950 views
0 votes
2 answers

How do I interact with a smart contract on a private network through web3.js

I found a blog that explains how ...READ MORE

Aug 20, 2018 in Blockchain by slayer
• 29,370 points
3,944 views
0 votes
1 answer

Hyperledger Fabric peer command not found error.

This error occurs when the system can ...READ MORE

Jul 2, 2018 in Blockchain by Omkar
• 69,220 points
3,924 views
+1 vote
1 answer

Hyperledger Fabric: Got permission denied Docker daemon socket at unix:///var/run/docker.sock

You are getting this error probably because ...READ MORE

Nov 19, 2018 in Blockchain by Omkar
• 69,220 points
3,890 views
+2 votes
3 answers

Hyperledger Fabric: Peer Connection error: Failed obtaining connection: Could not connect to any of the endpoints.

 You can extend your /etc/hosts file and make orderer.example.com domain name ...READ MORE

Nov 13, 2018 in Blockchain by Omkar
• 69,220 points
3,871 views
0 votes
1 answer
0 votes
2 answers

Truffle compile: SyntaxError: No visibility specified. Did you intend to add "public"?

You can try another method : contract HelloWorld{       function ...READ MORE

Mar 18, 2019 in Blockchain by anonymous
3,860 views
+1 vote
1 answer

Getting Hash160 bitcoin address in python

There is a package to decode and ...READ MORE

Aug 24, 2018 in Blockchain by slayer
• 29,370 points
3,832 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
3,821 views
0 votes
2 answers

Hyperledger Composer: Adding a new peer: failed to create a new connection: context deadline exceeded.

Seems like peer address problem. Set the ...READ MORE

May 6, 2019 in Blockchain by Tina
3,804 views
0 votes
1 answer

Solidity how to solve “Error Encoding arguments ” error while using create button?

When you pass multiple arguments, you need ...READ MORE

Jul 30, 2018 in Blockchain by slayer
• 29,370 points
3,789 views
–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
• 69,220 points
3,778 views