Blockchain | A simple implementation of blockchain in java | Blockchain library

by Will1229 Java Version: Current License: Apache-2.0

X-Ray Key Features Code Snippets Community Discussions(10)Vulnerabilities Install Support

kandi X-RAY | Blockchain Summary

Blockchain is a Java library typically used in Blockchain, Bitcoin, Spring Boot, Spring applications. Blockchain has no bugs, it has no vulnerabilities, it has build file available, it has a Permissive License and it has low support. You can download it from GitHub.

This project aims to create a simple implementation of blockchain concept and demostrate it in a user friendly way.

Support

Quality

Security

License

Reuse

Support

Blockchain has a low active ecosystem.

It has 286 star(s) with 111 fork(s). There are 36 watchers for this library.

It had no major release in the last 6 months.

There are 2 open issues and 2 have been closed. On average issues are closed in 509 days. There are no pull requests.

It has a neutral sentiment in the developer community.

The latest version of Blockchain is current.

Quality

Blockchain has 0 bugs and 0 code smells.

Security

Blockchain has no vulnerabilities reported, and its dependent libraries have no vulnerabilities reported.

Blockchain code analysis shows 0 unresolved vulnerabilities.

There are 0 security hotspots that need review.

License

Blockchain is licensed under the Apache-2.0 License. This license is Permissive.

Permissive licenses have the least restrictions, and you can use them in most projects.

Reuse

Blockchain releases are not available. You will need to build from source code and install.

Build file is available. You can build the component from source.

Installation instructions are not available. Examples and code snippets are available.

Blockchain saves you 291 person hours of effort in developing the same functionality from scratch.

It has 703 lines of code, 61 functions and 12 files.

It has medium code complexity. Code complexity directly impacts maintainability of the code.

Top functions reviewed by kandi - BETA

kandi has reviewed Blockchain and discovered the below as its top functions. This is intended to give you an instant insight into Blockchain implemented functionality, and help decide if they suit your requirements.

Runs the agent
Checks if a block is valid
Adds a block to the database
Get the list of registered blocks
Create a new block
Sends a message to a socket
Create a block
Creates a new block
Add a new agent
Starts the agent server
Add a new agent
Gets an agent
Gets the property name
Returns the agent with the given name
Deletes all agents
Delete all agents
Stop the host
Request all agents
Returns a list of all the agents
Deletes an agent
Removes the agent with the given name
Calculate the SHA - 256 hash of a string
Returns a unique hash code
Compares this block with the specified object
Gets the block of the agent with the given name
Entry point for the application

Get all kandi verified functions for this library.

Blockchain Key Features

No Key Features are available at this moment for Blockchain.

Blockchain Examples and Code Snippets

No Code Snippets are available at this moment for Blockchain.

Community Discussions

Trending Discussions on Blockchain

Why Metamask if web3.js can interact directly with ganache?

Error: Property 'body' cannot be accessed on 'Response?' because it is potentially null

How to send a web3 transaction from a test account of RSKj regtest blockchain node

How can I convert an [u8] hex ascii representation to a u64

The transaction declared chain ID 5777, but the connected node is on 1337

How to locally unit-test Chainlink's Verifiable Random Function?

I want to get the address from mnemonic with the proper derivation path

how to sign a message with ecdsa privatekey using golang?

Flag provided but not defined: -rpc

ParserError: Source file requires different compiler version

QUESTION

Why Metamask if web3.js can interact directly with ganache?

Asked 2022-Mar-30 at 17:55

I am new to blockchain app development, I saw a project where ganache accounts are imported into Metamask, then web3.js is used to access and print those accounts and balances on Frontend (user interface).

If web3.js can directly access ganache blockchain accounts and balances, why do we need Metamask in between?

...

ANSWER

Answered 2022-Feb-08 at 09:11

If web3.js can directly acccess ganache blockchain accounts and balances, why we need metamask in between?

In this case, you don't need MetaMask to sign the transaction, as the node (Ganache) holds your private key.

But in a public environment (testnets and mainnet), the node doesn't hold your private key, so you'd need to sign the transaction using MetaMask (or any other tool that holds the private key).

Source https://stackoverflow.com/questions/70952165

QUESTION

Error: Property 'body' cannot be accessed on 'Response?' because it is potentially null

Asked 2022-Mar-29 at 00:29

so I'am trying to learn dart and flutter and everything went well so far. But now I'am stuck at an error which I cannot handle. I coded a function which is supposed to asynchronously return the actual BTC price from https://blockchain.info/ticker.

Only thing it returns is errors:

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ANSWER

Answered 2022-Mar-29 at 00:29

To get rid of that error you need to use the bang operator to tell the compiler that snapshot.data won't be null.

Source https://stackoverflow.com/questions/71640944

QUESTION

How to send a web3 transaction from a test account of RSKj regtest blockchain node

Asked 2022-Mar-25 at 10:34

I am creating a DApp that connects to a smart contract deployed on a local test RSK blockchain (regtest) run by RSKj Java app. I intend to send transactions via Web3 connected to Metamask. In DApp I am getting the accounts list by sending a Web3 request:

...

ANSWER

Answered 2022-Mar-25 at 10:34

The first account from the list is referred as a “cow” seed in this file in RSKj. You can take the corresponding private key from there.

Do the following:

copy the private key c85ef7d79691fe79573b1a7064c19c1a9819ebdbd1faaab1a8ec92344438aaf4,
open your Metamask browser plugin
select regtest network
import the account
1. Account icon in the upper right corner
2. Import account
3. ‘Paste your private key string here:’
Set the just imported account as an active one
Enjoy sending your transactions

Source https://stackoverflow.com/questions/69450433

QUESTION

How can I convert an [u8] hex ascii representation to a u64

Asked 2022-Mar-17 at 10:57

I would like to convert my bytes array into a u64.

For example b"00" should return 0u64 b"0a" should return 10u64

I am working on blockchain, so I must find something efficient.
For example, my current function is not efficient at all.

...

ANSWER

Answered 2022-Mar-16 at 20:21

How about?

Source https://stackoverflow.com/questions/71501726

QUESTION

The transaction declared chain ID 5777, but the connected node is on 1337

Asked 2022-Mar-11 at 02:52

I am trying to deploy my SimpleStorage.sol contract to a ganache local chain by making a transaction using python. It seems to have trouble connecting to the chain.

...

ANSWER

Answered 2022-Jan-17 at 18:17

Had this issue myself, apparently it's some sort of Ganache CLI error but the simplest fix I could find was to change the network id in Ganache through settings>server to 1337. It restarts the session so you'd then need to change the address and private key variable.

If it's the same tutorial I'm doing, you're likely to come unstuck after this... the code for transaction should be:

Source https://stackoverflow.com/questions/70731492

QUESTION

How to locally unit-test Chainlink's Verifiable Random Function?

Asked 2022-Mar-08 at 04:12

Context

While trying to set up a basic self-hosted unit testing environment (and CI) that tests this Chainlink VRF random number contract, I am experiencing slight difficulties in how to simulate any relevant blockchains/testnets locally.

For example, I found this repository that tests Chainlinks VRF. However, for default deployment it suggests/requires a free KOVAN_RPC_URL e.g. from Infura's site and even for "local deployment" it suggests/requires a free MAINNET_RPC_URL from e.g. Alchemy's site.

Attempt/baseline

I adopted a unit test environment from the waffle framework which is described as:

Filestructure ...

ANSWER

Answered 2021-Sep-09 at 04:35

to test locally you need to make use of mocks which can simulate having an oracle network. Because you're working locally, a Chainlink node doesn't know about your local blockchain, so you can't actually do proper VRF requests. Note you can try deploy a local Chainlink node and a local blockchain and have them talk, but it isn't fully supported yet so you may get mixed results. Anyway, as per the hardhat starter kit that you linked, you can set the defaultNetwork to be 'hardhat' in the hardhat.config.js file, then when you deploy and run the integration tests (yarn test-integration), it will use mocks to mock up the VRF node, and to test the requesting of a random number. See the test here, and the mock contracts and linktoken get deployed here

Source https://stackoverflow.com/questions/69089799

QUESTION

I want to get the address from mnemonic with the proper derivation path

Asked 2022-Feb-23 at 00:41

I am very new to blockchain programming and programming in general. I want to generate my SOL address using the mnemonic seed phrase with the derivation path "m/44'/501'/0'/0". I can't find a proper BIP44 module for python where you can specify the derivation path.

...

ANSWER

Answered 2022-Feb-23 at 00:41

After a long search through the internet, I have finally found a way of solving my problem that I want to share with you.

Source https://stackoverflow.com/questions/71217530

QUESTION

how to sign a message with ecdsa privatekey using golang?

Asked 2022-Feb-20 at 14:48

I am trying to sign a message in go generated via hd wallet's private key using cosmos sdk. Below is the equivalent implementation in python which generates the signed message / signature as expected when submitted/verified is working properly but unable to get it working wtih Go implementation. Any inputs for equivalent golang version of the python implementation is much appreciated. Thank you.

Python version uses sha256 , ecdsa but when using the equivalent cyrpto/ecdsa doesn't return valid signature.

Python

...

ANSWER

Answered 2022-Feb-20 at 14:48

Both codes return hex encoded as private key

Source https://stackoverflow.com/questions/71186925

QUESTION

Flag provided but not defined: -rpc

Asked 2022-Feb-19 at 20:07

Am starting off in blockchain development using the book Mastering Blockchain - A deep dive into distributed ledgers, consensus protocols, smart contracts, DApps, cryptocurrencies, Ethereum,

Am using WSL with geth version 1.10.9.

...

ANSWER

Answered 2021-Oct-11 at 23:20

It appears 1.10.9-stable version has a problem and is returning a -rpc error. GETH 1.10.8-stable version works fine when running the geth command with --rpc

Source https://stackoverflow.com/questions/69463898

QUESTION

ParserError: Source file requires different compiler version

Asked 2022-Feb-08 at 13:18

I tried all that you mentioned in the discussion here (in other questions) and at https://github.com/smartcontractkit/full-blockchain-solidity-course-py/discussions/522 , however it is not solving the issue for me, I also noticed that the current compiler version remains (current compiler is 0.6.12+commit.27d51765.Windows.msvc). But when I right click and select Solidty:Compiler information, it shows 0.8.0.

from output:

...

ANSWER

Answered 2022-Jan-02 at 03:09

i had the same issue. i had this compiler setting:

Source https://stackoverflow.com/questions/70459922

Community Discussions, Code Snippets contain sources that include Stack Exchange Network

Vulnerabilities

No vulnerabilities reported

Install Blockchain

You can download it from GitHub.
You can use Blockchain like any standard Java library. Please include the the jar files in your classpath. You can also use any IDE and you can run and debug the Blockchain component as you would do with any other Java program. Best practice is to use a build tool that supports dependency management such as Maven or Gradle. For Maven installation, please refer maven.apache.org. For Gradle installation, please refer gradle.org .

Support

For any new features, suggestions and bugs create an issue on GitHub. If you have any questions check and ask questions on community page Stack Overflow .

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