Subchain

You've had a great idea for a software project, but nobody takes it serious because you're not using the latest shit aka blockchain technology?

Don't dispair, Subchain is here to help! Just include it on your project, use it to save some data nobody needs, and you call tell everyone you're on the blockchain!

Installation

Just install the package from npm:

npm install --save subchain

Type definitions for usage with TypeScript are already included.

Usage

Import the package:

var subchain = require('subchain');

Now you can create an empty blockchain and fill it with blocks:

var blockchain = new subchain.Blockchain();
blockchain.add({ number: 23, string: 'incredible' }, publicKey, privateKey);
blockchain.add({ number: 42 }, publicKey, privateKey);

The privateKey and publicKey parameters need to contain the private/public key used for the cryptographic singing of blocks. You can create these keys, for example, with openssl:

openssl genpkey -algorithm RSA -out private.pem -pkeyopt rsa_keygen_bits:2048
openssl rsa -pubout -in private.pem -out public.pem

A snapshot of the blockchains data can be retrieved with the head getter. This includes all data ever passed to the chain, while keys included on newer blocks overwrite those of older ones:

blockchain.head; // => { number: 42, string: 'incredible' }

You can verify the integrity of the chain at any time with the verify() method, which throws an exception if the validation fails.

blockchain.verify();

To serialize the blockchain, just call:

var serialized = blockchain.serialize();

This returns a Buffer you can write to disk, send over the wire, print out, our whatever you want to to with it.

To recreate the Blockchain instance from a serialized one, just pass it to the constructor:

var blockchain = new subchain.Blockchain(serialized);

Contributing

You want to make Subchain even greater as it is already? Spendid! I'd love to see pull requests for this incredible piece of software!