Parsing the Bitcoin block chain with Go language using Gocoin

package main
import (
    "log"
    "github.com/piotrnar/gocoin/blockdb"
    "github.com/piotrnar/gocoin/btc"
    "encoding/hex"
)

func main() {
    // Set real Bitcoin network
    Magic := [4]byte{0xF9,0xBE,0xB4,0xD9}

    // Specify blocks directory
    BlockDatabase := blockdb.NewBlockDB("/box/bitcoind_data/blocks", Magic)
    
    start_block := 0
    end_block := 275000

    for i := 0; i < end_block + 1; i++ {

        dat, er := BlockDatabase.FetchNextBlock()
        if dat==nil || er!=nil {
            log.Println("END of DB file")
            break
        }
        bl, er := btc.NewBlock(dat[:])

        if er != nil {
            println("Block inconsistent:", er.Error())
            break
        }

        // Read block till we reach start_block
        if i < start_block {
        	continue
        }

        log.Printf("Current block height: %v", i)

        // Basic block info
        log.Printf("Block hash: %v", bl.Hash)
        log.Printf("Block time: %v", bl.BlockTime)
        log.Printf("Block version: %v", bl.Version)
        log.Printf("Block parent: %v", btc.NewUint256(bl.Parent).String())
        log.Printf("Block merkle root: %v", hex.EncodeToString(bl.MerkleRoot))
        log.Printf("Block bits: %v", bl.Bits)
        log.Printf("Block size: %v", len(bl.Raw))

        // Fetch TXs and iterate over them
        bl.BuildTxList()
        for _, tx := range bl.Txs {
            log.Printf("TxId: %v", tx.Hash.String())
            log.Printf("Tx Size: %v", tx.Size)
            log.Printf("Tx Lock time: %v", tx.Lock_time)
            log.Printf("Tx Version: %v", tx.Version)

            log.Println("TxIns:")

            if tx.IsCoinBase() {
                log.Printf("TxIn coinbase, newly generated coins")
            } else {
                for txin_index, txin := range tx.TxIn {
                    log.Printf("TxIn index: %v", txin_index)
                    log.Printf("TxIn Input: %v", txin.Input.String())
                    log.Printf("TxIn ScriptSig: %v", hex.EncodeToString(txin.ScriptSig))
                    log.Printf("TxIn Sequence: %v", txin.Sequence)
                }
            }

            log.Println("TxOuts:")

            for txo_index, txout := range tx.TxOut {
                log.Printf("TxOut index: %v", txo_index)
                log.Printf("TxOut value: %v", txout.Value)
                log.Printf("TxOut script: %s", hex.EncodeToString(txout.Pk_script))
                txout_addr := btc.NewAddrFromPkScript(txout.Pk_script, false)
                if txout_addr != nil {
                    log.Printf("TxOut address: %v", txout_addr.String())
                } else {
                    log.Printf("TxOut address: can't decode address")
                }
            }
        }
        log.Println()
    }
}

2013/12/17 22:07:46 Current block height: 0
2013/12/17 22:07:46 Block hash: 000000000019d6689c085ae165831e934ff763ae46a2a6c172b3f1b60a8ce26f
2013/12/17 22:07:46 Block time: 1231006505
2013/12/17 22:07:46 TxId: 4a5e1e4baab89f3a32518a88c31bc87f618f76673e2cc77ab2127b7afdeda33b
2013/12/17 22:07:46 TxIns:
2013/12/17 22:07:46 TxIn coinbase, newly generated coins
2013/12/17 22:07:46 TxOuts:
2013/12/17 22:07:46 TxOut index: 0
2013/12/17 22:07:46 TxOut value: 5000000000
2013/12/17 22:07:46 TxOut address: 1A1zP1eP5QGefi2DMPTfTL5SLmv7DivfNa
2013/12/17 22:07:46 
2013/12/17 22:07:46 Current block height: 1
2013/12/17 22:07:46 Block hash: 00000000839a8e6886ab5951d76f411475428afc90947ee320161bbf18eb6048
2013/12/17 22:07:46 Block time: 1231469665
2013/12/17 22:07:46 TxId: 0e3e2357e806b6cdb1f70b54c3a3a17b6714ee1f0e68bebb44a74b1efd512098
2013/12/17 22:07:46 TxIns:
2013/12/17 22:07:46 TxIn coinbase, newly generated coins
2013/12/17 22:07:46 TxOuts:
2013/12/17 22:07:46 TxOut index: 0
2013/12/17 22:07:46 TxOut value: 5000000000
2013/12/17 22:07:46 TxOut address: 12c6DSiU4Rq3P4ZxziKxzrL5LmMBrzjrJX
2013/12/17 22:07:46 
2013/12/17 22:07:46 Current block height: 2
2013/12/17 22:07:46 Block hash: 000000006a625f06636b8bb6ac7b960a8d03705d1ace08b1a19da3fdcc99ddbd
2013/12/17 22:07:46 Block time: 1231469744
2013/12/17 22:07:46 TxId: 9b0fc92260312ce44e74ef369f5c66bbb85848f2eddd5a7a1cde251e54ccfdd5
2013/12/17 22:07:46 TxIns:
2013/12/17 22:07:46 TxIn coinbase, newly generated coins
2013/12/17 22:07:46 TxOuts:
2013/12/17 22:07:46 TxOut index: 0
2013/12/17 22:07:46 TxOut value: 5000000000
2013/12/17 22:07:46 TxOut address: 1HLoD9E4SDFFPDiYfNYnkBLQ85Y51J3Zb1
2013/12/17 22:07:46