Is there any python library could be used to decodescript in output

Question

For example decode the ScriptPubKey like

4104678afdb0fe5548271967f1a67130b7105cd6a828e03909a67962e0ea1f61deb649f6bc3f4cef38c4f35504e51ec112de5c384df7ba0b8d578a4c702b6bf11d5fac

to some data like this

{
"result": {
    "asm": "04678afdb0fe5548271967f1a67130b7105cd6a828e03909a67962e0ea1f61deb649f6bc3f4cef38c4f35504e51ec112de5c384df7ba0b8d578a4c702b6bf11d5f OP_CHECKSIG",
    "reqSigs": 1,
    "type": "pubkey",
    "addresses": [
        "1A1zP1eP5QGefi2DMPTfTL5SLmv7DivfNa"
    ],
    "p2sh": "3DjjKyU38gSfuVxajV43MUy4vHkg1JVL7T"
},
"error": null,
"id": null
}

In general, something like the function in decodescript rpc.
http://chainquery.com/bitcoin-api/decodescript

Answer 1

I just added that to my toy library.

>>> from btctools import decode_scriptpubkey
>>> decode_scriptpubkey('76a914b3c2dc3a7f68a024a5d2ee9d4012dca1134dea8588ac')
{'address': '1HPVPU3xHMPcxmgdP9puPbnDcHDV5JhURh',
 'asm': 'OP_DUP OP_HASH160 b3c2dc3a7f68a024a5d2ee9d4012dca1134dea85 OP_EQUALVERIFY OP_CHECKSIG',
 'hex': '76a914b3c2dc3a7f68a024a5d2ee9d4012dca1134dea8588ac',
 'type': 'P2PKH'}

Answer 2

Resolved and save the code in here. https://github.com/keviny/bitcoin-block-parser

Many details are found in https://en.bitcoin.it/wiki/Script.

The code to decode the ScriptPubKey in transaction output:

class TxOutput:
  def __init__(self, blockchain, idx):
    self.idx = idx
    self.value = uint8(blockchain)
    self.script_len = varint(blockchain)
    self.pubkey = blockchain.read(self.script_len)
    self.addr = "UNKNOWN"
    self.decode_scriptpubkey(self.pubkey)

  def to_string(self):
    sb = []
    sb.append("Value: %d" % self.value + " Satoshi")
    sb.append("Script Len: %d" % self.script_len)
    sb.append("ScriptPubkey: %s" % self.addr)
    sb.append("Addr: %s" % self.addr)
    return sb

  def decode_scriptpubkey(self, data):
    ''' https://en.bitcoin.it/wiki/Script '''
    hexstr = hashStr(data)
    # Get the first two bytes.
    # which might some problem.
    # https://www.blockchain.com/btc/tx/7bd54def72825008b4ca0f4aeff13e6be2c5fe0f23430629a9d484a1ac2a29b8
    try:
      op_idx = int(hexstr[0:2], 16)
    except:
      self.type = "EXCEPTION"
      self.addr = "UNKNOWN"
      return
    try:
      op_code = OPCODE_NAMES[op_idx]
    except KeyError:
      if op_idx==65:
        self.type = "P2PK"
        # Obsoleted pay to pubkey directly
        # For detail see: https://en.bitcoin.it/wiki/Script#Obsolete_pay-to-pubkey_transaction
        pub_key_len = op_idx
        op_code_tail = OPCODE_NAMES[int(hexstr[2 + pub_key_len * 2:2 + pub_key_len * 2 + 2], 16)]
        self.pubkey_human = "Pubkey OP_CODE: None Bytes:%s tail_op_code:%s %d" % (pub_key_len, op_code_tail, op_idx)
        self.addr = pubkey_to_address(hexstr[2:2 + pub_key_len * 2])[0]
      else:
        # Some times people will push data directly
        # e.g: https://www.blockchain.com/btc/tx/d65bb24f6289dad27f0f7e75e80e187d9b189a82dcf5a86fb1c6f8ff2b2c190f
        self.type = "UN"
        pub_key_len = op_idx
        self.pubkey_human = "PUSH_DATA:%s" % hexstr[2:2 + pub_key_len * 2]
        self.addr = "UNKNOWN"
      return
    try:
      if op_code == "OP_DUP":
        self.type = "P2PKHA"
        # P2PKHA pay to pubkey hash mode
        # For detail see: https://en.bitcoin.it/wiki/Script#Standard_Transaction_to_Bitcoin_address_.28pay-to-pubkey-hash.29
        op_code2 = OPCODE_NAMES[int(hexstr[2:4], 16)]
        pub_key_len = int(hexstr[4:6], 16)
        op_code_tail2 = OPCODE_NAMES[int(hexstr[6 + pub_key_len * 2:6 + pub_key_len * 2 + 2], 16)]
        op_code_tail_last = OPCODE_NAMES[int(hexstr[6 + pub_key_len * 2 + 2:6 + pub_key_len * 2 + 4], 16)]
        self.pubkey_human = "%s %s %s %s %s" % (op_code, op_code2,  hexstr[6:6 + pub_key_len * 2], op_code_tail2, op_code_tail_last)
        self.addr = gen_addr(hexstr[6:6 + pub_key_len * 2])[0]
      elif op_code == "OP_HASH160":
        self.type = "P2SH"
        # P2SHA pay to script hash
        # https://en.bitcoin.it/wiki/Transaction#Pay-to-Script-Hash
        pub_key_len = int(hexstr[2:4], 16)
        op_code_tail = OPCODE_NAMES[int(hexstr[4 + pub_key_len * 2:4 + pub_key_len * 2 + 2], 16)]
        hash_code = hexstr[4:4 + pub_key_len * 2]
        self.pubkey_human = "%s %s %s" % (op_code, hash_code, op_code_tail)
        self.addr = hash_code
      elif op_code == "OP_RETURN":
        self.type = "OP_RETURN"
        pub_key_len = int(hexstr[2:4], 16)
        hash_code = hexstr[4:4 + pub_key_len * 2]
        self.pubkey_human = "OP_RETURN %s" % (hash_code)
        self.addr = hash_code
      else:  # TODO extend for multi-signature parsing
        self.type = "UN"
        self.pubkey_human = "Need to extend multi-signaturer parsing %x" % int(hexstr[0:2], 16) + op_code
        self.addr = "UNKNOWN"
    except:
      self.type = "ERROR"
      self.addr = "UNKNOWN"