sphinxcontrib-xlink 1.2.0

A Sphinx extension for external link management via .xlink files.

sphinxcontrib-xlink

sphinxcontrib-xlink is a powerful Sphinx extension for managing, filtering, and structuring external hyperlinks through centralized data files. Instead of hardcoding URLs across your documentation, define them once in .xlink files and reference them dynamically to build inline links, nested lists, and browser-compatible bookmark files.

It also supercharges your authoring experience with a custom VSCode snippet engine that provides instant autocomplete for external links, glossary terms, document section headers, tags, files, and Sphinx-Needs dynamic functions.

Interactive Bookmark Search (HTML only)

Important: The search feature only works with HTML output (html, dirhtml, singlehtml, readthedocs builders). It renders a client-side JavaScript widget that is not available in LaTeX/PDF or other non-HTML builders.

The .. xlink-search:: directive embeds a fully interactive, real-time search interface directly into your documentation. Readers can instantly search, filter, and navigate your entire link database without leaving the page.

Key Capabilities

• Instant fuzzy search across link titles, IDs, tags, and URLs
• Smart tag filtering with tag: prefix — matches against tag slugs, display names, and descriptions
• Tag exclusion with -tag: or !tag: prefix
• URL filtering with inurl: and exclusion with -inurl: or !inurl:
• Autocomplete dropdown for tag names as you type tag:
• Match context highlights showing why a tag matched (displays the tag's display name and description with the matching term highlighted)
• Full keyboard navigation — Arrow keys, Tab, Enter to open links, Shift+Enter to copy :xlink: role to clipboard
• Global keyboard shortcut — ⌘+⇧+K (Mac) / Ctrl+Shift+K (Windows/Linux) to focus or open search
• Configurable results per page with persistent localStorage preference
• Overlay mode — renders as a modal dialog triggered by keyboard shortcut
• Custom styling via CSS classes

Basic Usage

.. xlink-search::

This renders a full-width search bar with a paginated results table containing all links from your .xlink files.

Configuration Examples

Custom title and page sizes:

.. xlink-search::
   :title: Project Bookmark Search
   :results: 5, 10, 25, 50

Overlay mode (hidden by default, opened via ⌘+⇧+K):

.. xlink-search::
   :overlay:
   :title: Quick Link Finder
   :results: 10, 25, 50, 100

Custom CSS class for styling:

.. xlink-search::
   :class: my-custom-search
   :title: Engineering Links
   :results: 20, 50

Search Syntax

Users can combine multiple search operators in a single query:

Syntax	Description	Example
<text>	Free-text search on title and ID	api docs
tag:<term>	Include links with matching tag (slug, name, or description)	tag:engineer
-tag:<term> or !tag:<term>	Exclude links with matching tag	-tag:internal
inurl:<term>	Include links whose URL contains the term	inurl:github.com
-inurl:<term> or !inurl:<term>	Exclude links whose URL contains the term	-inurl:internal.corp

Combined example: api tag:engineer -tag:internal inurl:github.com finds links with "api" in the title, tagged with something matching "engineer", excluding "internal" tags, and whose URL contains "github.com".

Keyboard Shortcuts (within the search widget)

Key	Action
⌘+⇧+K / Ctrl+Shift+K	Focus search input (or open overlay)
↓ / ↑	Navigate results table
Tab / Shift+Tab	Move selection forward/backward
Enter	Open selected link in new tab
Shift+Enter	Copy :xlink:\id`` to clipboard
Escape	Clear search / deselect / close overlay
Type any letter (while table focused)	Return focus to search input

Directive Options

Option	Type	Description
:title:	String	Header text displayed above the search bar
:results:	Comma-separated integers	Page size options for the dropdown (default: 10, 25, 50, 100)
:overlay:	Flag	Renders as a hidden overlay/modal, toggled via keyboard shortcut
:class:	String	Custom CSS classes on the container

---

Features

• Centralized Management: Store URLs, titles, and tags in simple, structured text files (.xlink).
• Deep Folder Structures: Recursively organize your .xlink files into nested directories. Create a hidden .xlink folder containing section-name.rst and section-description.rst to seamlessly generate rich metadata for an entire directory tree.
• Interactive Search (HTML only): Embed a real-time, keyboard-navigable search interface with tag autocomplete and fuzzy matching.
• Native Toctree Integration: Automatically inject your generated link hierarchies directly into the Sphinx toctree, allowing them to appear in your sidebar navigation.
• Collision-Proof Namespaces: Safely handles duplicate filenames (e.g., examples/example1.xlink and other/example1.xlink) and identically named sections by automatically tracking relative paths and generating full-path HTML anchor IDs.
• Python Expression Engine: Filter your link database dynamically using a secure Python evaluation engine (e.g., :query: "code" in tags and re.search('api', url)).
• N-Depth Tag Hierarchies: Build complex, multi-level grouped lists using a powerful nested tag syntax (e.g., manager[tracking[internal]]).
• Rich reST Descriptions: Inject reStructuredText-formatted descriptions into your file and tag categories for annotated link directories.
• Surgical Description Control: Use !file and !tag modifiers to hide descriptions for specific files, tags, or entire sub-trees based on their hierarchy path.
• Native Sphinx-Needs Support: Integrates directly with sphinx-needs dynamic functions and needs_string_links to make external links clickable in metadata tables.
• Intelligent VSCode Snippets: Automatically generates a .vscode snippet file customized to your project, resolving links, terms, section headers, tags, and files inline without requiring boilerplate replace directives.
• Bookmark Generation: Generate Netscape Bookmark HTML files with native browser tag support.
• LaTeX/PDF URL Control: Target how URLs are rendered in PDFs (inline, footnotes, or hidden).
• Link Checking: Verify that external links are still alive during the Sphinx build process.

---

Installation

Install the package via pip:

pip install sphinxcontrib-xlink

Add the extension to your conf.py:

extensions = [
    'sphinxcontrib.xlink',
    'sphinx_needs',  # Optional: for dynamic function support
]

---

Configuration (conf.py)

You don't need anything specific in your config to get started. Simply create an xlinks folder in your documentation source directory and create your first .xlink file (e.g., test.xlink).

# xlink-section-name: Test File
# xlink-section-description: Here you can add a description, with\n\nline breaks **and** rst formatting.

unique-id :: Link Title :: Link Location :: tag1, tag2, taggroup1:sub1, taggroup1:sub2, taggroup2:sub1, taggroup2:sub2,
test-mail :: Company Mail App :: https://companymail.example.com :: tool:mail, dept:communications

Reference the new link in your .rst file:

:xlink:`test-mail`

Full Configuration Options

Below you can find the available configuration options to customize sphinxcontrib-xlink to your needs:

# Directory containing .xlink files (Defaults to 'xlinks' relative to conf.py)
xlink_directory = '../xlinks'

# Hierarchical Tagging & Rich Descriptions
# Defaults to {} to avoid arbitrary tags and typos. Making tags explicit is recommended.
# Format: 'tag-name': ('Section Heading', 'Section Description')
xlink_allowed_tags = {
    'engineer': ('Software Engineer', 'Resources for the **technical** staff.'),
    'manager': ('Project Management', 'Links for tracking *milestones* and budgets.'),
    'tracking': ('Tracking Tools', 'Centralized apps for project health.'),
    'tool:mail': ('Mail Tools', 'Communication Suite, SMTP Tooling'),
    'internal': 'Internal Only',
    'external': 'Third-Party Services'
}

# Sphinx TOC Integration
# Define which builders automatically append lists to the Sphinx Document TOC tree.
xlink_add_to_toctree_builders = ['html', 'dirhtml', 'singlehtml', 'readthedocs']

# Sphinx-Needs Integration
# Specify which metadata fields should automatically use the xlink clickable mapping
xlink_needs_string_link_options = ['xlink', 'documentation', 'python-docs']

# Fallback name for untagged links
xlink_default_untagged_name = 'Uncategorized Links'

# Developer Experience (VSCode snippets generation)
xlink_generate_vscode_snippets = True

# Quality Assurance & URL Validation
xlink_check_links = False
xlink_check_timeout = 5.0

# PDF/LaTeX Output Control ('no', 'inline', 'footnote')
xlink_latex_show_urls = 'no'

# Visual Enhancements
xlink_render_link_icon = True
xlink_list_render_link_icon = False

Configuration Examples by Use Case

Minimal setup (just links, no tags):

extensions = ['sphinxcontrib.xlink']
xlink_directory = 'xlinks'

Strict tag governance (prevents typos, enables search descriptions):

xlink_allowed_tags = {
    'frontend': ('Frontend', 'UI frameworks and component libraries'),
    'backend': ('Backend', 'Server-side APIs and microservices'),
    'devops': ('DevOps', 'CI/CD, containers, and infrastructure'),
}
xlink_generate_vscode_snippets = True  # Tags appear in autocomplete

PDF-optimized output (show URLs as footnotes in LaTeX):

xlink_latex_show_urls = 'footnote'
xlink_render_link_icon = False  # Icons don't render in PDF

CI/CD link validation (check for broken links during build):

xlink_check_links = True
xlink_check_timeout = 10.0

---

Deep Folder Structures & Toctree Integration

As your link database scales, you can organize your .xlink files into recursive subfolders. The extension tracks the relative POSIX path of each file, ensuring that identical filenames in different folders never collide.

Example Directory Tree

xlinks/
├── example1.xlink
├── examples/
│   ├── .xlink/
│   │   ├── section-name.rst         <-- E.g. "Engineering Examples"
│   │   └── section-description.rst  <-- E.g. "Links for the engineering team..."
│   ├── example1.xlink               <-- Addressed as 'examples/example1'
│   └── subxample/
│       └── example2.xlink           <-- Addressed as 'examples/subxample/example2'

1. Adding to the Toctree

If you want these folders and files to act like native chapters in your documentation (appearing in the sidebar), use the :add-to-toctree: flag.

.. xlink-list::
   :group-by: file
   :add-to-toctree:

Note: Because html is in the xlink_add_to_toctree_builders config by default, you often don't even need to specify the flag manually for HTML builds! You can override this locally using :no-add-to-toctree:.

2. Targeting Specific Nested Files

To target or hide specific files when dealing with complex directories, always use the relative path:

.. xlink-list::
   :group-by: file
   :files: example1, examples/example1, !examples/subxample/example2

Prefixing a file with ! (e.g., !examples/subxample/example2) will show the links inside it, but suppress the file's metadata description.

3. Anchor Collision Protection

If you render multiple xlink-list directives on the same page grouped by the same parameters, Sphinx would normally generate colliding HTML IDs. sphinxcontrib-xlink automatically generates a unique id-prefix (e.g., xlink-0-, xlink-1-) combined with the full folder path to ensure all anchors and TOC links work flawlessly. You can also explicitly define your own:

.. xlink-list::
   :id-prefix: custom-prefix
   :group-by: file

---

The VSCode Developer Experience

When xlink_generate_vscode_snippets is enabled, the extension generates a customized set of .vscode/*.json.code-snippets files during the build process (e.g., make html).

To prevent these snippets from popping up annoyingly while you type standard words, all snippets require a deliberate intent prefix.

• ddxl- (Links): Autocomplete an external link from your .xlink files.
• ddxt- (Terms): Autocomplete a glossary term.
• ddxr- (Refs): Autocomplete an internal cross-reference to any section header.
• ddxn- (Needs): Autocomplete a dynamic [[ xlink('id') ]] function for sphinx-needs.
• ddxtag- (Tags): Autocomplete an allowed tag (shows description in the pop-up).
• ddxfile- (Files): Autocomplete a valid .xlink relative file path (shows file metadata in the pop-up).

Pro-Tip: You can also use ddxl-list-simple to instantly scaffold out fully-configured .. xlink-list:: directives with pre-filled dropdown menus for your valid tags and files!

---

Advanced Filtering: The Python Query Engine

As your link database grows, standard filter lists are no longer enough. The .. xlink-list:: directive includes a powerful :query: option that evaluates a Python expression against every link in your database.

The engine injects the following variables into the evaluation context:

• link_id (str)
• title (str)
• url (str)
• tags (set) — Exposed as a Python Set for easy intersection/subset operations!
• filename (str) — The relative path of the .xlink file (e.g., examples/example1)
• section_name (str)
• section_desc (str)
• re (module) — For regex matching

Safe builtins available: any, all, bool, set, len.

Exhaustive Query Examples

Here is how you can achieve complex filtering logic using natural Python syntax:

.. xlink-list::
   :query: <insert-expression-here>

Goal	Python :query: Expression
All links	True
Tags that start with 'role:'	any(t.startswith('role:') for t in tags)
Exclude the 'engineer' tag	"engineer" not in tags
Exclude both 'code' and 'manager'	not {"code", "manager"}.intersection(tags)
Tags containing specific regex	any(re.search('.*eat-mod.*', t) for t in tags)
Tags NOT containing specific regex	not any(re.search('.*:arch:.*', t) for t in tags)
Filter by file section name	re.search('.*Tools.*', section_name)
Desc matches 'local' OR ID matches 'iki'	re.search('.*local', section_desc) or re.search('.*iki.*', link_id)
Has BOTH 'code' AND 'manager' tags	{"code", "manager"}.issubset(tags)
Has EITHER 'code' OR 'engineer' tag	bool({"code", "engineer"}.intersection(tags))
Tag is 'code' AND Title ends in 'repo'	"code" in tags and re.search('.*repo$', title)
('code' OR 'engineer') AND URL matches	bool({"code", "engineer"}.intersection(tags)) and re.search('github\\.com', url)
Exclude 'code' AND (Title OR ID matches)	"code" not in tags and (re.search('.*repo$', title) or re.search('^api-', link_id))
Start with 'role:' from specific files	any(t.startswith('role:') for t in tags) and filename in ['example1', 'examples/example2']
'code' AND specific Section Names	"code" in tags and (re.search('.*-model', section_name) or re.search('To.*', section_name))

(Note: Sorting should be handled via the :sort-by: and :order: directive options rather than inside the Python query.)

---

Usage Examples

1. Inline Links

Type ddxl- in VSCode to select a link, or write it manually:

• Default Label: :xlink:example-repo renders using the title from the .xlink file.
• Custom Label: :xlink:Our Code renders as "Our Code".

2. Sphinx-Needs Metadata Tables

Using the xlink dynamic function allows you to pull URLs from your .xlink files directly into a needs metadata table. By default, sphinxcontrib-xlink registers a mapping that makes these links clickable in the frontend.

Single Link:

.. dr:: My decision
   :id: DR-0001
   :xlink: [[ xlink('example-repo') ]]

Multiple Links: You can pass multiple IDs as a comma-separated string.

.. dr:: Complex decision
   :id: DR-0002
   :xlink: [[ xlink('example-repo, example-mail') ]]

Additional dynamic functions are also registered:

• [[ xlink_url('id') ]] — returns only the URL
• [[ xlink_title('id') ]] — returns only the title

3. Hierarchical Tag Grouping

Create deeply nested structures. Use !tag (Single) and tag!! (Cascade) to control description visibility. Prefix files with !file to hide file descriptions.

.. xlink-list::
   :files: !example1, examples/example2
   :tags: !engineer[code, productivity-apps], manager!![tracking[internal]]
   :group-by: tag

Modifier Logic:

• !engineer: Hides the description for "engineer" only.
• manager!!: Shows "manager" description, but hides descriptions for all children (tracking, internal).
• !example1: Hides the file description for example1.

4. Bookmark Export

Generate a browser-compatible Netscape Bookmark .html file.

.. xlink-list::
   :group-by: tag, file
   :download-as-bookmarks: Project Reference Links
   :download-as-bookmarks-external-link: https://docs.example.com/bookmarks.html
   :render-list-with-bookmarks: after

5. Glossary Autocomplete & Auto-Resolution

sphinxcontrib-xlink completely eliminates the boilerplate of referencing Glossary Terms. Type ddxt- in VSCode and select your term. The extension natively transforms the placeholder into a cross-reference—no .. |replace| directives required!

• |xlink-term-smap| ➔ Renders as: SMAP
• |xlink-term-smap-full| ➔ Renders as: Supervisor Mode Access Prevention (SMAP)

6. Document Reference Autocomplete

The extension automatically assigns a normalized anchor label to every section header in your entire project. Type ddxr- in VSCode and select it.

• |xlink-ref-file-filtering| ➔ Renders as: File filtering

7. Interactive Search Widget (HTML only)

Add a searchable, filterable table of all your links:

.. xlink-search::
   :title: Find a Bookmark
   :results: 10, 25, 50

Or as a hidden overlay triggered by ⌘+⇧+K:

.. xlink-search::
   :overlay:
   :title: Quick Search

---

Directive Options Reference

.. xlink-list:: Options

Option	Value Type	Description
:query:	Python Expr.	Filter links using a Python expression (tags, link_id, url, filename, etc.).
:files:	Comma-separated	Restrict to specific relative paths (e.g. examples/example1). Prefix ! to hide desc.
:tags:	Hierarchy string	Filter by tags and define N-depth grouping (e.g., a[b, !c]).
:id-filter-regex:	Regex Patterns	(Legacy) Include links matching specific ID patterns.
:id-starts-with:	String	(Legacy) Simpler alternative to regex for matching link ID prefixes.
:url-filter-regex:	Regex Patterns	(Legacy) Include links matching specific URL patterns.
:title-filter-regex:	Regex Patterns	(Legacy) Include links matching specific Title patterns.
:group-by:	String	Grouping strategy: file, tag, file, tag, or tag, file.
:sort-by:	id or title	Sort links within their group.
:order:	asc or desc	Sort direction.
:download-as-bookmarks:	String	Generates a downloadable bookmark .html file.
:download-as-bookmarks-external-link:	URL	Fallback URL for the bookmark file (used in non-HTML builders).
:render-list-with-bookmarks:	before / after	Position of the download button relative to the list.
:latex-show-urls:	inline, footnote, no	LaTeX/PDF URL rendering style for this list.
:render-link-icon:	true or false	Override the global icon config for this specific list.
:class:	String	Inject custom CSS classes into the generated list container.
:add-to-toctree:	Flag	Append list sections to the Sphinx document TOC directly.
:no-add-to-toctree:	Flag	Prevents TOC integration (overrides conf.py default).
:id-prefix:	String	Custom prefix for HTML anchor IDs. Defaults to an auto-incrementing ID.

.. xlink-search:: Options (HTML only)

Option	Value Type	Description
:title:	String	Header text displayed above the search bar.
:results:	Comma-separated integers	Page size options for the results dropdown (default: 10, 25, 50, 100).
:overlay:	Flag	Render as a hidden modal overlay, toggled via ⌘+⇧+K / Ctrl+Shift+K.
:class:	String	Custom CSS classes applied to the search container.

:xlink: Role

Syntax	Result
:xlink:`link-id`	Renders with the title defined in the .xlink file
:xlink:`Custom Text <link-id>`	Renders with "Custom Text" as the label