GOcoin

Overview

A fork of https://github.com/utamaro/gocoin

This is a library to make bitcoin address and transactions which was initially forked from hellobitcoin, and added some useful features.

GOcoin uses btcec library in btcd instead of https://github.com/toxeus/go-secp256k1 to make it a pure GO program.

Features

1. Normaly Payment(P2PKH) supporting multi TxIns and multi TxOuts.
2. Gethering unspent transaction outputs(UTXO) and send transactions by using Blockr.io WEB API.
3. M of N multisig whose codes were partially ported from https://github.com/soroushjp/go-bitcoin-multisig.

Changes

1. Removed the "local" package btcec and changed the code to use github.com/btcsuite/btcd/btcec
2. Refactored a lot of code
3. Implements dynamic fee calculation using the API from 21.co

Requirements

This requires

• git
• go 1.5+

Installation

$ mkdir -p tmp/{src,bin,pkg}
$ cd tmp
$ export GOPATH=$(pwd)
$ go get github.com/klim8d/gocoin

Example

(This example omits error handlings for simplicity.)

Key Handling

import gocoin

func main(){
	//make a public and private key pair.
	key, _ := gocoin.GenerateKey(true)
	adr, _ := key.Pub.GetAddress()
	fmt.Println("address=", adr)
	wif := key.Priv.GetWIFAddress()
	fmt.Println("wif=", wif)
	
	//get key from wif
	wif := "928Qr9J5oAC6AYieWJ3fG3dZDjuC7BFVUqgu4GsvRVpoXiTaJJf"
	txKey, _ := gocoin.GetKeyFromWIF(wif)
}

Normal Payment

import gocoin

func main(){
	key, _ := gocoin.GenerateKey(true)

	//get unspent transactions
	service := gocoin.NewBlockrService(true)
	txs, _ := service.GetUTXO(adr,nil)
	
	//Normal Payment
	gocoin.Pay([]*Key{txKey}, []*gocoin.Amounts{&{gocoin.Amounts{"n2eMqTT929pb1RDNuqEnxdaLau1rxy3efi", 0.01*gocoin.BTC}}, service)
}

M of N Multisig

import gocoin

func main(){
	key, _ := gocoin.GenerateKey(true)
	service := gocoin.NewBlockrService(true)

	//2 of 3 multisig
	key1, _ := gocoin.GenerateKey(true)
	key2, _ := gocoin.GenerateKey(true)
	key3, _ := gocoin.GenerateKey(true)
	rs, _:= gocoin.NewRedeemScript(2, []*PublicKey{key1.Pub, key2.Pub, key3.Pub})
	//make a fund
	rs.Pay([]*Key{txKey}, 0.05*gocoin.BTC, service)

    //get a raw transaction for signing.
	rawtx, tx, _:= rs.CreateRawTransactionHashed([]*gocoin.Amounts{&{gocoin.Amounts{"n3Bp1hbgtmwDtjQTpa6BnPPCA8fTymsiZy", 0.05*gocoin.BTC}}, service)

	//spend the fund
	sign1, _:= key2.Priv.Sign(rawtx)
	sign2, _:= key3.Priv.Sign(rawtx)
	rs.Spend(tx, [][]byte{nil, sign1, sign2}, service)
}

Contribution

Improvements to the codebase and pull requests are encouraged.