Feature: Add support for per-page secondary sidebar content (#1572)

* Add ability to set per-page secondary sidebars

* Add additional secondary sidebar content tests; expanded utils docstring

docs/conf.py

@@ -180,7 +180,10 @@
     # "content_footer_items": ["test", "test"],
     "footer_start": ["copyright"],
     "footer_center": ["sphinx-version"],
-    # "secondary_sidebar_items": ["page-toc"],  # Remove the source buttons
+    "secondary_sidebar_items": {
+        "**/*": ["page-toc", "edit-this-page", "sourcelink"],
+        "examples/no-sidebar": [],
+    },
     "switcher": {
         "json_url": json_url,
         "version_match": version_match,

docs/examples/no-sidebar.md

@@ -6,6 +6,11 @@ This page shows off what the documentation looks like when you explicitly tell S
 html_sidebars = {
   "path/to/page": [],
 }
+html_theme_options = {
+    "secondary_sidebar_items": {
+        "path/to/page": [],
+    },
+}
 ```
 
-The primary sidebar should be entirely gone, and the main content should expand slightly to make up the extra space.
+Both the primary and secondary sidebars should be entirely gone, and the main content should expand slightly to make up the extra space.

docs/user_guide/page-toc.rst

@@ -24,3 +24,32 @@ Remove the Table of Contents
 
 To remove the Table of Contents, add ``:html_theme.sidebar_secondary.remove:`` to the `file-wide metadata <https://www.sphinx-doc.org/en/master/usage/restructuredtext/field-lists.html#file-wide-metadata>`_ at the top of a page.
 This will remove the Table of Contents from that page only.
+
+Per-page secondary-sidebar content
+----------------------------------
+
+``html_theme_options['secondary_sidebar_items']`` accepts either a ``list`` of secondary sidebar
+templates to render on every page:
+
+.. code-block:: python
+
+   html_theme_options = {
+     "secondary_sidebar_items": ["page-toc", "sourcelink"]
+   }
+
+or a ``dict`` which maps page names to ``list`` of secondary sidebar templates:
+
+.. code-block:: python
+
+   html_theme_options = {
+     "secondary_sidebar_items": {
+       "**": ["page-toc", "sourcelink"],
+       "index": ["page-toc"],
+     }
+   }
+
+If a ``dict`` is specified, the keys can contain glob-style patterns; page names which
+match the pattern will contain the sidebar templates specified. This closely follows the behavior of
+the ``html_sidebars`` option that is part of Sphinx itself, except that it operates on the
+secondary sidebar instead of the primary sidebar. For more information, see `the Sphinx
+documentation <https://www.sphinx-doc.org/en/master/usage/configuration.html#confval-html_sidebars>`__.

src/pydata_sphinx_theme/__init__.py

@@ -1,7 +1,6 @@
 """Bootstrap-based sphinx theme from the PyData community."""
 
 import json
-import os
 from functools import partial
 from pathlib import Path
 from typing import Dict
@@ -203,37 +202,19 @@ def update_and_remove_templates(
         "theme_footer_start",
         "theme_footer_center",
         "theme_footer_end",
-        "theme_secondary_sidebar_items",
         "theme_primary_sidebar_end",
         "sidebars",
     ]
     for section in template_sections:
         if context.get(section):
-            # Break apart `,` separated strings so we can use , in the defaults
-            if isinstance(context.get(section), str):
-                context[section] = [
-                    ii.strip() for ii in context.get(section).split(",")
-                ]
-
-            # Add `.html` to templates with no suffix
-            for ii, template in enumerate(context.get(section)):
-                if not os.path.splitext(template)[1]:
-                    context[section][ii] = template + ".html"
-
-            # If this is the page TOC, check if it is empty and remove it if so
-            def _remove_empty_templates(tname):
-                # These templates take too long to render, so skip them.
-                # They should never be empty anyway.
-                SKIP_EMPTY_TEMPLATE_CHECKS = ["sidebar-nav-bs.html", "navbar-nav.html"]
-                if not any(tname.endswith(temp) for temp in SKIP_EMPTY_TEMPLATE_CHECKS):
-                    # Render the template and see if it is totally empty
-                    rendered = app.builder.templates.render(tname, context)
-                    if len(rendered.strip()) == 0:
-                        return False
-                return True
-
-            context[section] = list(filter(_remove_empty_templates, context[section]))
-    #
+            context[section] = utils._update_and_remove_templates(
+                app=app,
+                context=context,
+                templates=context.get(section, []),
+                section=section,
+                templates_skip_empty_check=["sidebar-nav-bs.html", "navbar-nav.html"],
+            )
+
     # Remove a duplicate entry of the theme CSS. This is because it is in both:
     # - theme.conf
     # - manually linked in `webpack-macros.html`
@@ -296,6 +277,7 @@ def setup(app: Sphinx) -> Dict[str, str]:
     app.connect("html-page-context", toctree.add_toctree_functions)
     app.connect("html-page-context", update_and_remove_templates)
     app.connect("html-page-context", logo.setup_logo_path)
+    app.connect("html-page-context", utils.set_secondary_sidebar_items)
     app.connect("build-finished", pygment.overwrite_pygments_css)
     app.connect("build-finished", logo.copy_logo_images)
 

src/pydata_sphinx_theme/theme/pydata_sphinx_theme/sections/sidebar-secondary.html

@@ -1,6 +1,7 @@
-{% if theme_secondary_sidebar_items -%}
+{% if secondary_sidebar_items -%}
 <div class="sidebar-secondary-items sidebar-secondary__inner">
-{% for toc_item in theme_secondary_sidebar_items %}
+{# Note: secondary_sidebar_items is set by set_secondary_sidebar_items() in utils.py #}
+{% for toc_item in secondary_sidebar_items %}
   <div class="sidebar-secondary-item">{% include toc_item %}</div>
 {% endfor %}
 </div>

src/pydata_sphinx_theme/utils.py

@@ -1,11 +1,13 @@
 """General helpers for the management of config parameters."""
 
+import copy
+import os
 import re
-from typing import Any, Dict, Iterator
+from typing import Any, Dict, Iterator, List, Optional, Union
 
 from docutils.nodes import Node
 from sphinx.application import Sphinx
-from sphinx.util import logging
+from sphinx.util import logging, matching
 
 
 def get_theme_options_dict(app: Sphinx) -> Dict[str, Any]:
@@ -58,3 +60,112 @@ def maybe_warn(app: Sphinx, msg, *args, **kwargs):
     should_warn = theme_options.get("surface_warnings", False)
     if should_warn:
         SPHINX_LOGGER.warning(msg, *args, **kwargs)
+
+
+def set_secondary_sidebar_items(
+    app: Sphinx, pagename: str, templatename: str, context, doctree
+) -> None:
+    """Set the secondary sidebar items to render for the given pagename."""
+    if "theme_secondary_sidebar_items" in context:
+        templates = context["theme_secondary_sidebar_items"]
+        if isinstance(templates, dict):
+            templates = _get_matching_sidebar_items(pagename, templates)
+
+        context["secondary_sidebar_items"] = _update_and_remove_templates(
+            app,
+            context,
+            templates,
+            "theme_secondary_sidebar_items",
+        )
+
+
+def _update_and_remove_templates(
+    app: Sphinx,
+    context: Dict[str, Any],
+    templates: Union[List, str],
+    section: str,
+    templates_skip_empty_check: Optional[List[str]] = None,
+) -> List[str]:
+    """Update templates to include html suffix if needed; remove templates which render empty.
+
+    Args:
+        app: Sphinx application passed to the html page context
+        context: The html page context; dictionary of values passed to the templating engine
+        templates: A list of template names, or a string of comma separated template names
+        section: Name of the template section where the templates are to be rendered. Valid
+            section names include any of the ``sphinx`` or ``html_theme_options`` that take templates
+            or lists of templates as arguments, for example: ``theme_navbar_start``,
+            ``theme_primary_sidebar_end``, ``theme_secondary_sidebar_items``, ``sidebars``, etc. For
+            a complete list of valid section names, see the source for
+            :py:func:`pydata_sphinx_theme.update_and_remove_templates` and
+            :py:func:`pydata_sphinx_theme.utils.set_secondary_sidebar_items`, both of which call
+            this function.
+        templates_skip_empty_check: Names of any templates which should never be removed from the list
+            of filtered templates returned by this function. These templates aren't checked if they
+            render empty, which can save time if the template is slow to render.
+
+    Returns:
+        A list of template names (including '.html' suffix) to render into the section
+    """
+    if templates_skip_empty_check is None:
+        templates_skip_empty_check = []
+
+    # Break apart `,` separated strings so we can use , in the defaults
+    if isinstance(templates, str):
+        templates = [template.strip() for template in templates.split(",")]
+
+    # Add `.html` to templates with no suffix
+    suffixed_templates = []
+    for template in templates:
+        if os.path.splitext(template)[1]:
+            suffixed_templates.append(template)
+        else:
+            suffixed_templates.append(f"{template}.html")
+
+    ctx = copy.copy(context)
+    ctx.update({section: suffixed_templates})
+
+    # Check whether the template renders to an empty string; remove if this is the case
+    # Skip templates that are slow to render with templates_skip_empty_check
+    filtered_templates = []
+    for template in suffixed_templates:
+        if any(template.endswith(item) for item in templates_skip_empty_check):
+            filtered_templates.append(template)
+        else:
+            rendered = app.builder.templates.render(template, ctx)
+            if len(rendered.strip()) != 0:
+                filtered_templates.append(template)
+
+    return filtered_templates
+
+
+def _get_matching_sidebar_items(
+    pagename: str, sidebars: Dict[str, List[str]]
+) -> List[str]:
+    """Get the matching sidebar templates to render for the given pagename.
+
+    If a page matches more than one pattern, a warning is emitted, and the templates for the
+    last matching pattern are used.
+
+    This function was adapted from sphinx.builders.html.StandaloneHTMLBuilder.add_sidebars.
+    """
+    matched = None
+    secondary_sidebar_items = []
+    for pattern, sidebar_items in sidebars.items():
+        if matching.patmatch(pagename, pattern):
+            if matched and _has_wildcard(pattern) and _has_wildcard(matched):
+                SPHINX_LOGGER.warning(
+                    f"Page {pagename} matches two wildcard patterns in secondary_sidebar_items: {matched} and {pattern}"
+                ),
+
+            matched = pattern
+            secondary_sidebar_items = sidebar_items
+    return secondary_sidebar_items
+
+
+def _has_wildcard(pattern: str) -> bool:
+    """Check whether the pattern contains a wildcard.
+
+    Taken from sphinx.builders.StandaloneHTMLBuilder.add_sidebars.
+    """
+    return any(char in pattern for char in "*?[")

tests/sites/sidebars/index.rst

@@ -11,3 +11,8 @@ Sidebar depth variations
    :caption: Caption 2
 
    section2/index
+
+Other content
+-------------
+
+This is some other content.

tests/sites/sidebars/section1/index.rst

@@ -6,3 +6,8 @@ Section 1 index
 
    subsection1/index
    page2
+
+Other Content
+-------------
+
+This is some other content

tests/sites/sidebars/section1/subsection1/page2.rst

@@ -1,2 +1,6 @@
 Section 1 sub 1 page 2
 ======================
+
+
+Section A
+---------

tests/sites/sidebars/section2/index.rst

@@ -5,3 +5,9 @@ Section 2 index
 
    page1
    https://google.com
+
+
+Other Content
+-------------
+
+This is some other content