"""Allow `MathJax`_ to be used to display math in Sphinx's HTML writer.
This requires the MathJax JavaScript library on your webserver/computer.
.. _MathJax: https://www.mathjax.org/
"""
import json
from typing import Any, Dict, cast
from docutils import nodes
import sphinx
from sphinx.application import Sphinx
from sphinx.domains.math import MathDomain
from sphinx.errors import ExtensionError
from sphinx.locale import _
from sphinx.util.math import get_node_equation_number
from sphinx.writers.html import HTMLTranslator
# more information for mathjax secure url is here:
# https://docs.mathjax.org/en/latest/start.html#secure-access-to-the-cdn
MATHJAX_URL = 'https://cdn.jsdelivr.net/npm/mathjax@3/es5/tex-mml-chtml.js'
logger = sphinx.util.logging.getLogger(__name__)
def html_visit_math(self: HTMLTranslator, node: nodes.math) -> None:
self.body.append(self.starttag(node, 'span', '', CLASS='math notranslate nohighlight'))
self.body.append(self.builder.config.mathjax_inline[0] +
self.encode(node.astext()) +
self.builder.config.mathjax_inline[1] + '</span>')
raise nodes.SkipNode
def html_visit_displaymath(self: HTMLTranslator, node: nodes.math_block) -> None:
self.body.append(self.starttag(node, 'div', CLASS='math notranslate nohighlight'))
if node['nowrap']:
self.body.append(self.encode(node.astext()))
self.body.append('</div>')
raise nodes.SkipNode
# necessary to e.g. set the id property correctly
if node['number']:
number = get_node_equation_number(self, node)
self.body.append('<span class="eqno">(%s)' % number)
self.add_permalink_ref(node, _('Permalink to this equation'))
self.body.append('</span>')
self.body.append(self.builder.config.mathjax_display[0])
parts = [prt for prt in node.astext().split('\n\n') if prt.strip()]
if len(parts) > 1: # Add alignment if there are more than 1 equation
self.body.append(r' \begin{align}\begin{aligned}')
for i, part in enumerate(parts):
part = self.encode(part)
if r'\\' in part:
self.body.append(r'\begin{split}' + part + r'\end{split}')
else:
self.body.append(part)
if i < len(parts) - 1: # append new line if not the last equation
self.body.append(r'\\')
if len(parts) > 1: # Add alignment if there are more than 1 equation
self.body.append(r'\end{aligned}\end{align} ')
self.body.append(self.builder.config.mathjax_display[1])
self.body.append('</div>\n')
raise nodes.SkipNode
def install_mathjax(app: Sphinx, pagename: str, templatename: str, context: Dict,
event_arg: Any) -> None:
if app.builder.format != 'html' or app.builder.math_renderer_name != 'mathjax': # type: ignore # NOQA
return
if not app.config.mathjax_path:
raise ExtensionError('mathjax_path config value must be set for the '
'mathjax extension to work')
domain = cast(MathDomain, app.env.get_domain('math'))
if app.registry.html_assets_policy == 'always' or domain.has_equations(pagename):
# Enable mathjax only if equations exists
if app.config.mathjax2_config:
if app.config.mathjax_path == MATHJAX_URL:
logger.warning(
'mathjax_config/mathjax2_config does not work '
'for the current MathJax version, use mathjax3_config instead')
body = 'MathJax.Hub.Config(%s)' % json.dumps(app.config.mathjax2_config)
app.add_js_file(None, type='text/x-mathjax-config', body=body)
if app.config.mathjax3_config:
body = 'window.MathJax = %s' % json.dumps(app.config.mathjax3_config)
app.add_js_file(None, body=body)
options = {}
if app.config.mathjax_options:
options.update(app.config.mathjax_options)
if 'async' not in options and 'defer' not in options:
if app.config.mathjax3_config:
# Load MathJax v3 via "defer" method
options['defer'] = 'defer'
else:
# Load other MathJax via "async" method
options['async'] = 'async'
app.add_js_file(app.config.mathjax_path, **options)
def setup(app: Sphinx) -> Dict[str, Any]:
app.add_html_math_renderer('mathjax',
(html_visit_math, None),
(html_visit_displaymath, None))
app.add_config_value('mathjax_path', MATHJAX_URL, 'html')
app.add_config_value('mathjax_options', {}, 'html')
app.add_config_value('mathjax_inline', [r'\(', r'\)'], 'html')
app.add_config_value('mathjax_display', [r'\[', r'\]'], 'html')
app.add_config_value('mathjax_config', None, 'html')
app.add_config_value('mathjax2_config', lambda c: c.mathjax_config, 'html')
app.add_config_value('mathjax3_config', None, 'html')
app.connect('html-page-context', install_mathjax)
return {'version': sphinx.__display_version__, 'parallel_read_safe': True}