Lib/email/_compat21.py

   1 # Copyright (C) 2002 Python Software Foundation
   2 # Author: barry@zope.com
   3
   4 """Module containing compatibility functions for Python 2.1.
   5 """
   6
   7 from cStringIO import StringIO
   8 from types import StringType, UnicodeType
   9
  10 False = 0
  11 True = 1
  12
  13
  14 \f
  15 # This function will become a method of the Message class
  16 def walk(self):
  17     """Walk over the message tree, yielding each subpart.
  18
  19     The walk is performed in depth-first order.  This method is a
  20     generator.
  21     """
  22     parts = []
  23     parts.append(self)
  24     if self.is_multipart():
  25         for subpart in self.get_payload():
  26             parts.extend(subpart.walk())
  27     return parts
  28
  29
  30 # Python 2.2 spells floor division //
  31 def _floordiv(i, j):
  32     """Do a floor division, i/j."""
  33     return i / j
  34
  35
  36 def _isstring(obj):
  37     return isinstance(obj, StringType) or isinstance(obj, UnicodeType)
  38
  39
  40 \f
  41 # These two functions are imported into the Iterators.py interface module.
  42 # The Python 2.2 version uses generators for efficiency.
  43 def body_line_iterator(msg, decode=False):
  44     """Iterate over the parts, returning string payloads line-by-line.
  45
  46     Optional decode (default False) is passed through to .get_payload().
  47     """
  48     lines = []
  49     for subpart in msg.walk():
  50         payload = subpart.get_payload(decode=decode)
  51         if _isstring(payload):
  52             for line in StringIO(payload).readlines():
  53                 lines.append(line)
  54     return lines
  55
  56
  57 def typed_subpart_iterator(msg, maintype='text', subtype=None):
  58     """Iterate over the subparts with a given MIME type.
  59
  60     Use `maintype' as the main MIME type to match against; this defaults to
  61     "text".  Optional `subtype' is the MIME subtype to match against; if
  62     omitted, only the main type is matched.
  63     """
  64     parts = []
  65     for subpart in msg.walk():
  66         if subpart.get_content_maintype() == maintype:
  67             if subtype is None or subpart.get_content_subtype() == subtype:
  68                 parts.append(subpart)
  69     return parts