View file File name : iterators.py Content :# Copyright (C) 2001-2006 Python Software Foundation # Author: Barry Warsaw # Contact: email-sig@python.org """Various types of useful iterators and generators.""" __all__ = [ 'body_line_iterator', 'typed_subpart_iterator', 'walk', # Do not include _structure() since it's part of the debugging API. ] import sys from io import StringIO # This function will become a method of the Message class def walk(self): """Walk over the message tree, yielding each subpart. The walk is performed in depth-first order. This method is a generator. """ yield self if self.is_multipart(): for subpart in self.get_payload(): yield from subpart.walk() # These two functions are imported into the Iterators.py interface module. def body_line_iterator(msg, decode=False): """Iterate over the parts, returning string payloads line-by-line. Optional decode (default False) is passed through to .get_payload(). """ for subpart in msg.walk(): payload = subpart.get_payload(decode=decode) if isinstance(payload, str): yield from StringIO(payload) def typed_subpart_iterator(msg, maintype='text', subtype=None): """Iterate over the subparts with a given MIME type. Use `maintype' as the main MIME type to match against; this defaults to "text". Optional `subtype' is the MIME subtype to match against; if omitted, only the main type is matched. """ for subpart in msg.walk(): if subpart.get_content_maintype() == maintype: if subtype is None or subpart.get_content_subtype() == subtype: yield subpart def _structure(msg, fp=None, level=0, include_default=False): """A handy debugging aid""" if fp is None: fp = sys.stdout tab = ' ' * (level * 4) print(tab + msg.get_content_type(), end='', file=fp) if include_default: print(' [%s]' % msg.get_default_type(), file=fp) else: print(file=fp) if msg.is_multipart(): for subpart in msg.get_payload(): _structure(subpart, fp, level+1, include_default)