conf.py

# Matplotlib documentation build configuration file, created by
# sphinx-quickstart on Fri May  2 12:33:25 2008.
#
# This file is execfile()d with the current directory set to its containing
# dir.
#
# The contents of this file are pickled, so don't put values in the namespace
# that aren't picklable (module imports are okay, they're removed
# automatically).
#
# All configuration values have a default value; values that are commented out
# serve to show the default value.

import logging
import os
from pathlib import Path
import shutil
import subprocess
import sys
from urllib.parse import urlsplit, urlunsplit
import warnings
import yaml

import matplotlib

from datetime import datetime
import time

# debug that building expected version
print(f"Building Documentation for Matplotlib: {matplotlib.__version__}")

# Release mode enables optimizations and other related options.
is_release_build = tags.has('release')  # noqa

# are we running circle CI?
CIRCLECI = 'CIRCLECI' in os.environ


def _parse_skip_subdirs_file():
    """
    Read .mpl_skip_subdirs.yaml for subdirectories to not
    build if we do `make html-skip-subdirs`.  Subdirectories
    are relative to the toplevel directory.  Note that you
    cannot skip 'users' as it contains the table of contents,
    but you can skip subdirectories of 'users'.  Doing this
    can make partial builds very fast.
    """
    default_skip_subdirs = ['users/prev_whats_new/*', 'api/*', 'gallery/*',
                            'tutorials/*', 'plot_types/*', 'devel/*']
    try:
        with open(".mpl_skip_subdirs.yaml", 'r') as fin:
            print('Reading subdirectories to skip from',
                  '.mpl_skip_subdirs.yaml')
            out = yaml.full_load(fin)
        return out['skip_subdirs']
    except FileNotFoundError:
        # make a default:
        with open(".mpl_skip_subdirs.yaml", 'w') as fout:
            yamldict = {'skip_subdirs': default_skip_subdirs,
                        'comment': 'For use with make html-skip-subdirs'}
            yaml.dump(yamldict, fout)
        print('Skipping subdirectories, but .mpl_skip_subdirs.yaml',
              'not found so creating a default one. Edit this file',
              'to customize which directories are included in build.')

        return default_skip_subdirs


skip_subdirs = []
# triggered via make html-skip-subdirs
if 'skip_sub_dirs=1' in sys.argv:
    skip_subdirs = _parse_skip_subdirs_file()

# Parse year using SOURCE_DATE_EPOCH, falling back to current time.
# https://reproducible-builds.org/specs/source-date-epoch/
sourceyear = datetime.utcfromtimestamp(
    int(os.environ.get('SOURCE_DATE_EPOCH', time.time()))).year

# If your extensions are in another directory, add it here. If the directory
# is relative to the documentation root, use os.path.abspath to make it
# absolute, like shown here.
sys.path.append(os.path.abspath('.'))
sys.path.append('.')

# General configuration
# ---------------------

# Unless we catch the warning explicitly somewhere, a warning should cause the
# docs build to fail. This is especially useful for getting rid of deprecated
# usage in the gallery.
warnings.filterwarnings('error', append=True)

# Add any Sphinx extension module names here, as strings. They can be
# extensions coming with Sphinx (named 'sphinx.ext.*') or your custom ones.
extensions = [
    'sphinx.ext.autodoc',
    'sphinx.ext.autosummary',
    'sphinx.ext.inheritance_diagram',
    'sphinx.ext.intersphinx',
    'sphinx.ext.ifconfig',
    'IPython.sphinxext.ipython_console_highlighting',
    'IPython.sphinxext.ipython_directive',
    'numpydoc',  # Needs to be loaded *after* autodoc.
    'sphinx_gallery.gen_gallery',
    'matplotlib.sphinxext.mathmpl',
    'matplotlib.sphinxext.plot_directive',
    'sphinxcontrib.inkscapeconverter',
    'sphinxext.custom_roles',
    'sphinxext.github',
    'sphinxext.math_symbol_table',
    'sphinxext.missing_references',
    'sphinxext.mock_gui_toolkits',
    'sphinxext.skip_deprecated',
    'sphinxext.redirect_from',
    'sphinx_copybutton',
    'sphinx_design',
]

exclude_patterns = [
    'api/prev_api_changes/api_changes_*/*'
]

exclude_patterns += skip_subdirs


def _check_dependencies():
    names = {
        **{ext: ext.split(".")[0] for ext in extensions},
        # Explicitly list deps that are not extensions, or whose PyPI package
        # name does not match the (toplevel) module name.
        "colorspacious": 'colorspacious',
        "mpl_sphinx_theme": 'mpl_sphinx_theme',
        "sphinxcontrib.inkscapeconverter": 'sphinxcontrib-svg2pdfconverter',
    }
    missing = []
    for name in names:
        try:
            __import__(name)
        except ImportError:
            missing.append(names[name])
    if missing:
        raise ImportError(
            "The following dependencies are missing to build the "
            f"documentation: {', '.join(missing)}")
    if shutil.which('dot') is None:
        raise OSError(
            "No binary named dot - graphviz must be installed to build the "
            "documentation")

_check_dependencies()


# Import only after checking for dependencies.
# gallery_order.py from the sphinxext folder provides the classes that
# allow custom ordering of sections and subsections of the gallery
import sphinxext.gallery_order as gallery_order

# The following import is only necessary to monkey patch the signature later on
from sphinx_gallery import gen_rst

# On Linux, prevent plt.show() from emitting a non-GUI backend warning.
os.environ.pop("DISPLAY", None)

autosummary_generate = True

# we should ignore warnings coming from importing deprecated modules for
# autodoc purposes, as this will disappear automatically when they are removed
warnings.filterwarnings('ignore', category=DeprecationWarning,
                        module='importlib',  # used by sphinx.autodoc.importer
                        message=r'(\n|.)*module was deprecated.*')

autodoc_docstring_signature = True
autodoc_default_options = {'members': None, 'undoc-members': None}

# make sure to ignore warnings that stem from simply inspecting deprecated
# class-level attributes
warnings.filterwarnings('ignore', category=DeprecationWarning,
                        module='sphinx.util.inspect')

nitpicky = True
# change this to True to update the allowed failures
missing_references_write_json = False
missing_references_warn_unused_ignores = False

intersphinx_mapping = {
    'Pillow': ('https://pillow.readthedocs.io/en/stable/', None),
    'cycler': ('https://matplotlib.org/cycler/', None),
    'dateutil': ('https://dateutil.readthedocs.io/en/stable/', None),
    'ipykernel': ('https://ipykernel.readthedocs.io/en/latest/', None),
    'numpy': ('https://numpy.org/doc/stable/', None),
    'pandas': ('https://pandas.pydata.org/pandas-docs/stable/', None),
    'pytest': ('https://pytest.org/en/stable/', None),
    'python': ('https://docs.python.org/3/', None),
    'scipy': ('https://docs.scipy.org/doc/scipy/', None),
    'tornado': ('https://www.tornadoweb.org/en/stable/', None),
    'xarray': ('https://docs.xarray.dev/en/stable/', None),
}


# Sphinx gallery configuration

def matplotlib_reduced_latex_scraper(block, block_vars, gallery_conf,
                                     **kwargs):
    """
    Reduce srcset when creating a PDF.

    Because sphinx-gallery runs *very* early, we cannot modify this even in the
    earliest builder-inited signal. Thus we do it at scraping time.
    """
    from sphinx_gallery.scrapers import matplotlib_scraper

    if gallery_conf['builder_name'] == 'latex':
        gallery_conf['image_srcset'] = []
    return matplotlib_scraper(block, block_vars, gallery_conf, **kwargs)

gallery_dirs = [f'{ed}' for ed in ['gallery', 'tutorials', 'plot_types']
                if f'{ed}/*' not in skip_subdirs]

example_dirs = [f'../{gd}'.replace('gallery', 'examples') for gd in
                gallery_dirs]

sphinx_gallery_conf = {
    'backreferences_dir': Path('api') / Path('_as_gen'),
    # Compression is a significant effort that we skip for local and CI builds.
    'compress_images': ('thumbnails', 'images') if is_release_build else (),
    'doc_module': ('matplotlib', 'mpl_toolkits'),
    'examples_dirs': example_dirs,
    'filename_pattern': '^((?!sgskip).)*$',
    'gallery_dirs': gallery_dirs,
    'image_scrapers': (matplotlib_reduced_latex_scraper, ),
    'image_srcset': ["2x"],
    'junit': '../test-results/sphinx-gallery/junit.xml' if CIRCLECI else '',
    'matplotlib_animations': True,
    'min_reported_time': 1,
    'plot_gallery': 'True',  # sphinx-gallery/913
    'reference_url': {'matplotlib': None},
    'remove_config_comments': True,
    'reset_modules': (
        'matplotlib',
        # clear basic_units module to re-register with unit registry on import
        lambda gallery_conf, fname: sys.modules.pop('basic_units', None)
    ),
    'subsection_order': gallery_order.sectionorder,
    'thumbnail_size': (320, 224),
    'within_subsection_order': gallery_order.subsectionorder,
    'capture_repr': (),
}

if 'plot_gallery=0' in sys.argv:
    # Gallery images are not created.  Suppress warnings triggered where other
    # parts of the documentation link to these images.

    def gallery_image_warning_filter(record):
        msg = record.msg
        for pattern in (sphinx_gallery_conf['gallery_dirs'] +
                        ['_static/constrained_layout']):
            if msg.startswith(f'image file not readable: {pattern}'):
                return False

        if msg == 'Could not obtain image size. :scale: option is ignored.':
            return False

        return True

    logger = logging.getLogger('sphinx')
    logger.addFilter(gallery_image_warning_filter)


mathmpl_fontsize = 11.0
mathmpl_srcset = ['2x']

# Monkey-patching gallery header to include search keywords
gen_rst.EXAMPLE_HEADER = """
.. DO NOT EDIT.
.. THIS FILE WAS AUTOMATICALLY GENERATED BY SPHINX-GALLERY.
.. TO MAKE CHANGES, EDIT THE SOURCE PYTHON FILE:
.. "{0}"
.. LINE NUMBERS ARE GIVEN BELOW.

.. only:: html

    .. meta::
        :keywords: codex

    .. note::
        :class: sphx-glr-download-link-note

        Click :ref:`here <sphx_glr_download_{1}>`
        to download the full example code{2}

.. rst-class:: sphx-glr-example-title

.. _sphx_glr_{1}:

"""

# Add any paths that contain templates here, relative to this directory.
templates_path = ['_templates']

# The suffix of source filenames.
source_suffix = '.rst'

# This is the default encoding, but it doesn't hurt to be explicit
source_encoding = "utf-8"

# The toplevel toctree document (renamed to root_doc in Sphinx 4.0)
root_doc = master_doc = 'users/index'

# General substitutions.
try:
    SHA = subprocess.check_output(
        ['git', 'describe', '--dirty']).decode('utf-8').strip()
# Catch the case where git is not installed locally, and use the setuptools_scm
# version number instead
except (subprocess.CalledProcessError, FileNotFoundError):
    SHA = matplotlib.__version__


html_context = {
    "doc_version": SHA,
}

project = 'Matplotlib'
copyright = (
    '2002–2012 John Hunter, Darren Dale, Eric Firing, Michael Droettboom '
    'and the Matplotlib development team; '
    f'2012–{sourceyear} The Matplotlib development team'
)


# The default replacements for |version| and |release|, also used in various
# other places throughout the built documents.
#
# The short X.Y version.

version = matplotlib.__version__
# The full version, including alpha/beta/rc tags.
release = version

# There are two options for replacing |today|: either, you set today to some
# non-false value, then it is used:
# today = ''
# Else, today_fmt is used as the format for a strftime call.
today_fmt = '%B %d, %Y'

# List of documents that shouldn't be included in the build.
unused_docs = []

# If true, '()' will be appended to :func: etc. cross-reference text.
# add_function_parentheses = True

# If true, the current module name will be prepended to all description
# unit titles (such as .. function::).
# add_module_names = True

# If true, sectionauthor and moduleauthor directives will be shown in the
# output. They are ignored by default.
# show_authors = False

# The name of the Pygments (syntax highlighting) style to use.
pygments_style = 'sphinx'

default_role = 'obj'

# Plot directive configuration
# ----------------------------

# For speedup, decide which plot_formats to build based on build targets:
#     html only -> png
#     latex only -> pdf
#     all other cases, including html + latex -> png, pdf
# For simplicity, we assume that the build targets appear in the command line.
# We're falling back on using all formats in case that assumption fails.
formats = {'html': ('png', 100), 'latex': ('pdf', 100)}
plot_formats = [formats[target] for target in ['html', 'latex']
                if target in sys.argv] or list(formats.values())


# GitHub extension

github_project_url = "https://github.com/matplotlib/matplotlib/"


# Options for HTML output
# -----------------------

def add_html_cache_busting(app, pagename, templatename, context, doctree):
    """
    Add cache busting query on CSS and JavaScript assets.

    This adds the Matplotlib version as a query to the link reference in the
    HTML, if the path is not absolute (i.e., it comes from the `_static`
    directory) and doesn't already have a query.
    """
    from sphinx.builders.html import Stylesheet, JavaScript

    css_tag = context['css_tag']
    js_tag = context['js_tag']

    def css_tag_with_cache_busting(css):
        if isinstance(css, Stylesheet) and css.filename is not None:
            url = urlsplit(css.filename)
            if not url.netloc and not url.query:
                url = url._replace(query=SHA)
                css = Stylesheet(urlunsplit(url), priority=css.priority,
                                 **css.attributes)
        return css_tag(css)

    def js_tag_with_cache_busting(js):
        if isinstance(js, JavaScript) and js.filename is not None:
            url = urlsplit(js.filename)
            if not url.netloc and not url.query:
                url = url._replace(query=SHA)
                js = JavaScript(urlunsplit(url), priority=js.priority,
                                **js.attributes)
        return js_tag(js)

    context['css_tag'] = css_tag_with_cache_busting
    context['js_tag'] = js_tag_with_cache_busting


# The style sheet to use for HTML and HTML Help pages. A file of that name
# must exist either in Sphinx' static/ path, or in one of the custom paths
# given in html_static_path.
html_css_files = [
    "mpl.css",
]

html_theme = "mpl_sphinx_theme"

# The name for this set of Sphinx documents.  If None, it defaults to
# "<project> v<release> documentation".
# html_title = None

# The name of an image file (within the static path) to place at the top of
# the sidebar.
html_logo = "_static/logo2.svg"
html_theme_options = {
    "navbar_links": "internal",
    # collapse_navigation in pydata-sphinx-theme is slow, so skipped for local
    # and CI builds https://github.com/pydata/pydata-sphinx-theme/pull/386
    "collapse_navigation": not is_release_build,
    "show_prev_next": False,
    "switcher": {
        "json_url": "https://matplotlib.org/devdocs/_static/switcher.json",
        "version_match": (
            # The start version to show. This must be in switcher.json.
            # We either go to 'stable' or to 'devdocs'
            'stable' if matplotlib.__version_info__.releaselevel == 'final'
            else 'devdocs')
    },
    "logo": {"link": "index",
             "image_light": "images/logo2.svg",
             "image_dark": "images/logo_dark.svg"},
    "navbar_end": ["theme-switcher", "version-switcher", "mpl_icon_links"],
    "secondary_sidebar_items": "page-toc.html",
     "footer_items": ["copyright", "sphinx-version", "doc_version"],
}
include_analytics = is_release_build
if include_analytics:
    html_theme_options["analytics"] = {"google_analytics_id": "UA-55954603-1"}

# Add any paths that contain custom static files (such as style sheets) here,
# relative to this directory. They are copied after the builtin static files,
# so a file named "default.css" will overwrite the builtin "default.css".
html_static_path = ['_static']

# If nonempty, this is the file name suffix for generated HTML files.  The
# default is ``".html"``.
html_file_suffix = '.html'

# this makes this the canonical link for all the pages on the site...
html_baseurl = 'https://matplotlib.org/stable/'

# If not '', a 'Last updated on:' timestamp is inserted at every page bottom,
# using the given strftime format.
html_last_updated_fmt = '%b %d, %Y'

# Content template for the index page.
html_index = 'index.html'

# Custom sidebar templates, maps document names to template names.
# html_sidebars = {}

# Custom sidebar templates, maps page names to templates.
html_sidebars = {
    "index": [
        # 'sidebar_announcement.html',
        "sidebar_versions.html",
        "cheatsheet_sidebar.html",
        "donate_sidebar.html",
    ],
    # '**': ['localtoc.html', 'pagesource.html']
}

# Copies only relevant code, not the '>>>' prompt
copybutton_prompt_text = r'>>> |\.\.\. '
copybutton_prompt_is_regexp = True

# If true, add an index to the HTML documents.
html_use_index = False

# If true, generate domain-specific indices in addition to the general index.
# For e.g. the Python domain, this is the global module index.
html_domain_index = False

# If true, the reST sources are included in the HTML build as _sources/<name>.
# html_copy_source = True

# If true, an OpenSearch description file will be output, and all pages will
# contain a <link> tag referring to it.
html_use_opensearch = 'https://matplotlib.org/stable'

# Output file base name for HTML help builder.
htmlhelp_basename = 'Matplotlibdoc'

# Use typographic quote characters.
smartquotes = False

# Path to favicon
html_favicon = '_static/favicon.ico'

# Options for LaTeX output
# ------------------------

# The paper size ('letter' or 'a4').
latex_paper_size = 'letter'

# Grouping the document tree into LaTeX files.
# List of tuples:
#   (source start file, target name, title, author,
#    document class [howto/manual])

latex_documents = [
    (root_doc, 'Matplotlib.tex', 'Matplotlib',
     'John Hunter\\and Darren Dale\\and Eric Firing\\and Michael Droettboom'
     '\\and and the matplotlib development team', 'manual'),
]


# The name of an image file (relative to this directory) to place at the top of
# the title page.
latex_logo = None

# Use Unicode aware LaTeX engine
latex_engine = 'xelatex'  # or 'lualatex'

latex_elements = {}

# Keep babel usage also with xelatex (Sphinx default is polyglossia)
# If this key is removed or changed, latex build directory must be cleaned
latex_elements['babel'] = r'\usepackage{babel}'

# Font configuration
# Fix fontspec converting " into right curly quotes in PDF
# cf https://github.com/sphinx-doc/sphinx/pull/6888/
latex_elements['fontenc'] = r'''
\usepackage{fontspec}
\defaultfontfeatures[\rmfamily,\sffamily,\ttfamily]{}
'''

# Sphinx 2.0 adopts GNU FreeFont by default, but it does not have all
# the Unicode codepoints needed for the section about Mathtext
# "Writing mathematical expressions"
latex_elements['fontpkg'] = r"""
\IfFontExistsTF{XITS}{
 \setmainfont{XITS}
}{
 \setmainfont{XITS}[
  Extension      = .otf,
  UprightFont    = *-Regular,
  ItalicFont     = *-Italic,
  BoldFont       = *-Bold,
  BoldItalicFont = *-BoldItalic,
]}
\IfFontExistsTF{FreeSans}{
 \setsansfont{FreeSans}
}{
 \setsansfont{FreeSans}[
  Extension      = .otf,
  UprightFont    = *,
  ItalicFont     = *Oblique,
  BoldFont       = *Bold,
  BoldItalicFont = *BoldOblique,
]}
\IfFontExistsTF{FreeMono}{
 \setmonofont{FreeMono}
}{
 \setmonofont{FreeMono}[
  Extension      = .otf,
  UprightFont    = *,
  ItalicFont     = *Oblique,
  BoldFont       = *Bold,
  BoldItalicFont = *BoldOblique,
]}
% needed for \mathbb (blackboard alphabet) to actually work
\usepackage{unicode-math}
\IfFontExistsTF{XITS Math}{
 \setmathfont{XITS Math}
}{
 \setmathfont{XITSMath-Regular}[
  Extension      = .otf,
]}
"""

# Fix fancyhdr complaining about \headheight being too small
latex_elements['passoptionstopackages'] = r"""
    \PassOptionsToPackage{headheight=14pt}{geometry}
"""

# Additional stuff for the LaTeX preamble.
latex_elements['preamble'] = r"""
   % Show Parts and Chapters in Table of Contents
   \setcounter{tocdepth}{0}
   % One line per author on title page
   \DeclareRobustCommand{\and}%
     {\end{tabular}\kern-\tabcolsep\\\begin{tabular}[t]{c}}%
   \usepackage{etoolbox}
   \AtBeginEnvironment{sphinxthebibliography}{\appendix\part{Appendices}}
   \usepackage{expdlist}
   \let\latexdescription=\description
   \def\description{\latexdescription{}{} \breaklabel}
   % But expdlist old LaTeX package requires fixes:
   % 1) remove extra space
   \makeatletter
   \patchcmd\@item{{\@breaklabel} }{{\@breaklabel}}{}{}
   \makeatother
   % 2) fix bug in expdlist's way of breaking the line after long item label
   \makeatletter
   \def\breaklabel{%
       \def\@breaklabel{%
           \leavevmode\par
           % now a hack because Sphinx inserts \leavevmode after term node
           \def\leavevmode{\def\leavevmode{\unhbox\voidb@x}}%
      }%
   }
   \makeatother
"""
# Sphinx 1.5 provides this to avoid "too deeply nested" LaTeX error
# and usage of "enumitem" LaTeX package is unneeded.
# Value can be increased but do not set it to something such as 2048
# which needlessly would trigger creation of thousands of TeX macros
latex_elements['maxlistdepth'] = '10'
latex_elements['pointsize'] = '11pt'

# Better looking general index in PDF
latex_elements['printindex'] = r'\footnotesize\raggedright\printindex'

# Documents to append as an appendix to all manuals.
latex_appendices = []

# If false, no module index is generated.
latex_use_modindex = True

latex_toplevel_sectioning = 'part'

# Show both class-level docstring and __init__ docstring in class
# documentation
autoclass_content = 'both'

texinfo_documents = [
    (root_doc, 'matplotlib', 'Matplotlib Documentation',
     'John Hunter@*Darren Dale@*Eric Firing@*Michael Droettboom@*'
     'The matplotlib development team',
     'Matplotlib', "Python plotting package", 'Programming',
     1),
]

# numpydoc config

numpydoc_show_class_members = False

# We want to prevent any size limit, as we'll add scroll bars with CSS.
inheritance_graph_attrs = dict(dpi=100, size='1000.0', splines='polyline')
# Also remove minimum node dimensions, and increase line size a bit.
inheritance_node_attrs = dict(height=0.02, margin=0.055, penwidth=1,
                              width=0.01)
inheritance_edge_attrs = dict(penwidth=1)

graphviz_dot = shutil.which('dot')
# Still use PNG until SVG linking is fixed
# https://github.com/sphinx-doc/sphinx/issues/3176
# graphviz_output_format = 'svg'

# -----------------------------------------------------------------------------
# Source code links
# -----------------------------------------------------------------------------
link_github = True
# You can add build old with link_github = False

if link_github:
    import inspect
    from packaging.version import parse

    extensions.append('sphinx.ext.linkcode')

    def linkcode_resolve(domain, info):
        """
        Determine the URL corresponding to Python object
        """
        if domain != 'py':
            return None

        modname = info['module']
        fullname = info['fullname']

        submod = sys.modules.get(modname)
        if submod is None:
            return None

        obj = submod
        for part in fullname.split('.'):
            try:
                obj = getattr(obj, part)
            except AttributeError:
                return None

        if inspect.isfunction(obj):
            obj = inspect.unwrap(obj)
        try:
            fn = inspect.getsourcefile(obj)
        except TypeError:
            fn = None
        if not fn or fn.endswith('__init__.py'):
            try:
                fn = inspect.getsourcefile(sys.modules[obj.__module__])
            except (TypeError, AttributeError, KeyError):
                fn = None
        if not fn:
            return None

        try:
            source, lineno = inspect.getsourcelines(obj)
        except (OSError, TypeError):
            lineno = None

        linespec = (f"#L{lineno:d}-L{lineno + len(source) - 1:d}"
                    if lineno else "")

        startdir = Path(matplotlib.__file__).parent.parent
        try:
            fn = os.path.relpath(fn, start=startdir).replace(os.path.sep, '/')
        except ValueError:
            return None

        if not fn.startswith(('matplotlib/', 'mpl_toolkits/')):
            return None

        version = parse(matplotlib.__version__)
        tag = 'main' if version.is_devrelease else f'v{version.public}'
        return ("https://github.com/matplotlib/matplotlib/blob"
                f"/{tag}/lib/{fn}{linespec}")
else:
    extensions.append('sphinx.ext.viewcode')


# -----------------------------------------------------------------------------
# Sphinx setup
# -----------------------------------------------------------------------------
def setup(app):
    if any(st in version for st in ('post', 'dev', 'alpha', 'beta')):
        bld_type = 'dev'
    else:
        bld_type = 'rel'
    app.add_config_value('skip_sub_dirs', 0, '')
    app.add_config_value('releaselevel', bld_type, 'env')
    app.connect('html-page-context', add_html_cache_busting, priority=1000)