ASCII text string to binary string and vise versa (Python2/3 compatible)

binasciicoder.py

# -*- coding: utf-8 -*-

'''
How to use binascii

	1. ASCII text string to hex string
		hex_string = binascii.hexlify(<ASCII_TEXT>.encode('utf-8'))

Hex string to ASCII text string

	1. (python2,3)
		ascii_text = binascii.unhexlify(<HEX_STRING>).decode('utf-8')

	2. (python3)
		n = int(<HEX_STRING>, 16)
		ascii_text = n.to_bytes((n.bit_length() + 7) // 8, 'big').decode('utf-8')

	3. (python3)
		ascii_text = bytearray.fromhex(<HEX_STRING>).decode('utf-8')

	4. (python2)
		ascii_text = <HEX_STRING>.decode('hex')
'''

import sys

if sys.version_info[0] >= 3:


	def ascii_to_bits(s, encoding='utf-8', errors='surrogatepass'):
		"""ASCII text string to binary string."""
		bits = bin(int.from_bytes(s.encode(encoding, errors), 'big'))[2:]
		return bits.zfill(8 * ((len(bits) + 7) // 8))


	def bits_to_ascii(s, encoding='utf-8', errors='surrogatepass'):
		"""Binary string to ASCII text string."""
		n = int(s, 2)
		return n.to_bytes((n.bit_length() + 7) // 8, 'big').decode(encoding, errors) or '\x00'


else:
	import binascii


	def ascii_to_bits(s, encoding='utf-8', errors='surrogatepass'):
		"""ASCII text string to binary string."""
		bits = bin(int(binascii.hexlify(s.encode(encoding, errors)), 16))[2:]
		return bits.zfill(8 * ((len(bits) + 7) // 8))


	def bits_to_ascii(s, encoding='utf-8', errors='surrogatepass'):
		"""Binary string to ASCII text string."""
		n = int(s, 2)
		return _int_to_bytes(n).decode(encoding, errors)


	def _int_to_bytes(s, i):
		hex_string = hex(i)
		n = len(hex_string)
		return binascii.unhexlify(hex_string.zfill(n + (n & 1)))