# Copyright (C) 2001-2006 Python Software Foundation # Author: Barry Warsaw # Contact: email-sig@python.org """Encodings and related functions.""" from __future__ import unicode_literals from __future__ import division from __future__ import absolute_import from future.builtins import str __all__ = [ 'encode_7or8bit', 'encode_base64', 'encode_noop', 'encode_quopri', ] try: from base64 import encodebytes as _bencode except ImportError: # Py2 compatibility. TODO: test this! from base64 import encodestring as _bencode from quopri import encodestring as _encodestring def _qencode(s): enc = _encodestring(s, quotetabs=True) # Must encode spaces, which quopri.encodestring() doesn't do return enc.replace(' ', '=20') def encode_base64(msg): """Encode the message's payload in Base64. Also, add an appropriate Content-Transfer-Encoding header. """ orig = msg.get_payload() encdata = str(_bencode(orig), 'ascii') msg.set_payload(encdata) msg['Content-Transfer-Encoding'] = 'base64' def encode_quopri(msg): """Encode the message's payload in quoted-printable. Also, add an appropriate Content-Transfer-Encoding header. """ orig = msg.get_payload() encdata = _qencode(orig) msg.set_payload(encdata) msg['Content-Transfer-Encoding'] = 'quoted-printable' def encode_7or8bit(msg): """Set the Content-Transfer-Encoding header to 7bit or 8bit.""" orig = msg.get_payload() if orig is None: # There's no payload. For backwards compatibility we use 7bit msg['Content-Transfer-Encoding'] = '7bit' return # We play a trick to make this go fast. If encoding/decode to ASCII # succeeds, we know the data must be 7bit, otherwise treat it as 8bit. try: if isinstance(orig, str): orig.encode('ascii') else: orig.decode('ascii') except UnicodeError: charset = msg.get_charset() output_cset = charset and charset.output_charset # iso-2022-* is non-ASCII but encodes to a 7-bit representation if output_cset and output_cset.lower().startswith('iso-2022-'): msg['Content-Transfer-Encoding'] = '7bit' else: msg['Content-Transfer-Encoding'] = '8bit' else: msg['Content-Transfer-Encoding'] = '7bit' if not isinstance(orig, str): msg.set_payload(orig.decode('ascii', 'surrogateescape')) def encode_noop(msg): """Do nothing.""" # Well, not quite *nothing*: in Python3 we have to turn bytes into a string # in our internal surrogateescaped form in order to keep the model # consistent. orig = msg.get_payload() if not isinstance(orig, str): msg.set_payload(orig.decode('ascii', 'surrogateescape'))