Trying to get the table of contents from a doctree

docutils_get_toc.py

#! /usr/bin/env python
# -*- coding: utf-8 -*-
import docutils
from docutils import io
from docutils.core import Publisher, publish_doctree, publish_from_doctree
from docutils.transforms.parts import Contents
from docutils.writers.html5_polyglot import Writer


contents = """

=========
Hey world
=========

what's up
---------

ok



"""


def publish_parts_from_doctree(document, destination_path=None,
                               writer=None, writer_name='pseudoxml',
                               settings=None, settings_spec=None,
                               settings_overrides=None, config_section=None,
                               enable_exit_status=False):
    """
    Set up & run a `Publisher` to render from an existing document
    tree data structure, for programmatic use with string I/O.  Return
    the encoded string output.

    Note that document.settings is overridden; if you want to use the settings
    of the original `document`, pass settings=document.settings.

    Also, new document.transformer and document.reporter objects are
    generated.

    For encoded string output, be sure to set the 'output_encoding' setting to
    the desired encoding.  Set it to 'unicode' for unencoded Unicode string
    output.  Here's one way::

        publish_from_doctree(
            ..., settings_overrides={'output_encoding': 'unicode'})

    Parameters: `document` is a `docutils.nodes.document` object, an existing
    document tree.

    Other parameters: see `publish_programmatically`.
    """
    reader = docutils.readers.doctree.Reader(parser_name='null')
    pub = Publisher(reader, None, writer,
                    source=io.DocTreeInput(document),
                    destination_class=io.StringOutput, settings=settings)
    if not writer and writer_name:
        pub.set_writer(writer_name)
    pub.process_programmatic_settings(
        settings_spec, settings_overrides, config_section)
    pub.set_destination(None, destination_path)
    pub.publish(enable_exit_status=enable_exit_status)
    return pub.writer.parts


# parts for the contents
doc = publish_doctree(
    source=contents,
)
publish_from_doctree(doc, writer=Writer())
# from ptpdb import set_trace
# set_trace()
# from docutils.transforms.peps import Contents
doc.transformer.add_transform(Contents)

# ok so how do I get the TOC?

print(publish_parts_from_doctree(doc, writer=Writer()))

just_the_contents = publish_parts_from_doctree(
    document=doc,
    writer=Writer(),
)


print('All I want to have in html_body is: \n%s' %
      just_the_contents['html_body'])