vnegi10 / btcparser.jl

A Bitcoin blockchain parser in pure Julia

BTCParser.jl

About

A pure Julia implementation of a Bitcoin blockchain parser. Before using BTCParser.jl you must install a bitcoin client and download the entire blockchain.

Bitcoin core should save the blockchain data into $HOME/.bitcoin/blocks, BTCParser.jl will look there by default. You can change this directory by setting the environmental variable BTCPARSER_BLOCK_DIR.

Usage

Read the chain:

using BTCParser

# this takes ~2-3 minues on a SATA SSD
chain = make_chain()

Extract the Genesis Block

genesis_block = Block(chain[0])

Extract Block at height h

block = Block(chain[h])

chain indexing is 0-based to match the numbering used by the bitcoin core client, if you require 1-based indexing, use chain.data[h].

Get the hash of a block

double_sha256(genesis_block)
double_sha256(chain[0])

Get the header of a block

Header(chain[1])
Header(genesis_block)

Access transactions

genesis_tx = genesis_block.transactions[1]

Hashing transactions

double_sha256(genesis_tx)

Update an existing chain (in case the bitcoin client is running in the background)

chain = make_chain(chain)

Problems

• Currently only tested on amd64 architectures under Linux
  • many of the internals are endian-dependent and may not work on other architectures.
  • Paths are different under Windows/MacOS.
• Testing requires a working copy of the Bitcoin blockchain (200GB) and therefore testing on travis is difficult.
• Grep the code for "TODO" for more stuff.
• Please report any issues or improvement proposals here.