• __all__
• io
• walk
• body_line_iterator
• typed_subpart_iterator
• _structure

   1 # Copyright (C) 2001-2006 Python Software Foundation
   2 # Author: Barry Warsaw
   3 # Contact: email-sig@python.org
   4 
   5 """Various types of useful iterators and generators."""
   6 
   7 __all__ = [
   8     'body_line_iterator',
   9     'typed_subpart_iterator',
  10     'walk',
  11     # Do not include _structure() since it's part of the debugging API.
  12     ]
  13 
  14 import sys
  15 from io import StringIO
  16 
  17 
  18 
  19 # This function will become a method of the Message class
  20 def walk(self):
  21     """Walk over the message tree, yielding each subpart.
  22 
  23     The walk is performed in depth-first order.  This method is a
  24     generator.
  25     """
  26     yield self
  27     if self.is_multipart():
  28         for subpart in self.get_payload():
  29             yield from subpart.walk()
  30 
  31 
  32 
  33 # These two functions are imported into the Iterators.py interface module.
  34 def body_line_iterator(msg, decode=False):
  35     """Iterate over the parts, returning string payloads line-by-line.
  36 
  37     Optional decode (default False) is passed through to .get_payload().
  38     """
  39     for subpart in msg.walk():
  40         payload = subpart.get_payload(decode=decode)
  41         if isinstance(payload, str):
  42             yield from StringIO(payload)
  43 
  44 
  45 def typed_subpart_iterator(msg, maintype='text', subtype=None):
  46     """Iterate over the subparts with a given MIME type.
  47 
  48     Use `maintype' as the main MIME type to match against; this defaults to
  49     "text".  Optional `subtype' is the MIME subtype to match against; if
  50     omitted, only the main type is matched.
  51     """
  52     for subpart in msg.walk():
  53         if subpart.get_content_maintype() == maintype:
  54             if subtype is None or subpart.get_content_subtype() == subtype:
  55                 yield subpart
  56 
  57 
  58 
  59 def _structure(msg, fp=None, level=0, include_default=False):
  60     """A handy debugging aid"""
  61     if fp is None:
  62         fp = sys.stdout
  63     tab = ' ' * (level * 4)
  64     print(tab + msg.get_content_type(), end='', file=fp)
  65     if include_default:
  66         print(' [%s]' % msg.get_default_type(), file=fp)
  67     else:
  68         print(file=fp)
  69     if msg.is_multipart():
  70         for subpart in msg.get_payload():
  71             _structure(subpart, fp, level+1, include_default)