Method parse

code-ch08/tx.py:268–281

Takes a byte stream and parses the tx_input at the start return a TxIn object

(cls, s)

    @classmethod
    def parse(cls, s):
        '''Takes a byte stream and parses the tx_input at the start
        return a TxIn object
        '''
        # prev_tx is 32 bytes, little endian
        prev_tx = s.read(32)[::-1]
        # prev_index is an integer in 4 bytes, little endian
        prev_index = little_endian_to_int(s.read(4))
        # use Script.parse to get the ScriptSig
        script_sig = Script.parse(s)
        # sequence is an integer in 4 bytes, little-endian
        sequence = little_endian_to_int(s.read(4))
        # return an instance of the class (see __init__ for args)
        return cls(prev_tx, prev_index, script_sig, sequence)

    def serialize(self):
        '''Returns the byte serialization of the transaction input'''