View file File name : encoders.py Content :# Copyright (C) 2001-2006 Python Software Foundation # Author: Barry Warsaw # Contact: email-sig@python.org """Encodings and related functions.""" __all__ = [ 'encode_7or8bit', 'encode_base64', 'encode_noop', 'encode_quopri', ] import base64 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 _bencode(s): # We can't quite use base64.encodestring() since it tacks on a "courtesy # newline". Blech! if not s: return s hasnewline = (s[-1] == '\n') value = base64.encodestring(s) if not hasnewline and value[-1] == '\n': return value[:-1] return value def encode_base64(msg): """Encode the message's payload in Base64. Also, add an appropriate Content-Transfer-Encoding header. """ orig = msg.get_payload() encdata = _bencode(orig) 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 to ASCII succeeds, we # know the data must be 7bit, otherwise treat it as 8bit. try: orig.encode('ascii') except UnicodeError: msg['Content-Transfer-Encoding'] = '8bit' else: msg['Content-Transfer-Encoding'] = '7bit' def encode_noop(msg): """Do nothing."""