:mod:`email.iterators`: Iterators

:mod:email.iterators: Iterators

.. module:: email.iterators :synopsis: Iterate over a message object tree.

Source code: :source:Lib/email/iterators.py

Iterating over a message object tree is fairly easy with the :meth:Message.walk <email.message.Message.walk> method. The :mod:email.iterators module provides some useful higher level iterations over message object trees.

.. function:: body_line_iterator(msg, decode=False)

This iterates over all the payloads in all the subparts of msg, returning the string payloads line-by-line. It skips over all the subpart headers, and it skips over any subpart with a payload that isn't a Python string. This is somewhat equivalent to reading the flat text representation of the message from a file using :meth:~io.TextIOBase.readline, skipping over all the intervening headers.

Optional decode is passed through to :meth:Message.get_payload <email.message.Message.get_payload>.

.. function:: typed_subpart_iterator(msg, maintype='text', subtype=None)

This iterates over all the subparts of msg, returning only those subparts that match the MIME type specified by maintype and subtype.

Note that subtype is optional; if omitted, then subpart MIME type matching is done only with the main type. maintype is optional too; it defaults to :mimetype:text.

Thus, by default :func:typed_subpart_iterator returns each subpart that has a MIME type of :mimetype:text/\*.

The following function has been added as a useful debugging tool. It should not be considered part of the supported public interface for the package.

.. function:: _structure(msg, fp=None, level=0, include_default=False)

Prints an indented representation of the content types of the message object structure. For example:

.. testsetup::

  import email
  from email.iterators import _structure
  somefile = open('../Lib/test/test_email/data/msg_02.txt')

.. doctest::

  >>> msg = email.message_from_file(somefile)
  >>> _structure(msg)
  multipart/mixed
      text/plain
      text/plain
      multipart/digest
          message/rfc822
              text/plain
          message/rfc822
              text/plain
          message/rfc822
              text/plain
          message/rfc822
              text/plain
          message/rfc822
              text/plain
      text/plain

.. testcleanup::

  somefile.close()

Optional fp is a file-like object to print the output to. It must be suitable for Python's :func:print function. level is used internally. include_default, if true, prints the default type as well.