Sphinx

# `sphinx.ext.extlinks` – Markup to shorten external links

Module author: Georg Brandl

Added in version 1.0.

This extension is meant to help with the common pattern of having many external links that point to URLs on one and the same site, e.g. links to bug trackers, version control web interfaces, or simply subpages in other websites. It does so by providing aliases to base URLs, so that you only need to give the subpage name when creating a link.

Let’s assume that you want to include many links to issues at the Sphinx tracker, at `https://github.com/sphinx-doc/sphinx/issues/num`. Typing this URL again and again is tedious, so you can use `extlinks` to avoid repeating yourself.

The extension adds a config value:

extlinks
  Type:
    `dict[str, tuple[str, str | None]]`
  Default:
    `{}`

  This config value must be a dictionary of external sites, mapping unique short alias names to a base URL and a caption. For example, to create an alias for the above mentioned issues, you would add

      extlinks = {'issue': ('https://github.com/sphinx-doc/sphinx/issues/%s',
                            'issue %s')}

  Now, you can use the alias name as a new role, e.g. `:issue:`123``. This then inserts a link to https://github.com/sphinx-doc/sphinx/issues/123. As you can see, the target given in the role is substituted in the base URL in the place of `%s`.

  The link caption depends on the second item in the tuple, the caption:

  - If caption is `None`, the link caption is the full URL.

  - If caption is a string, then it must contain `%s` exactly once. In this case the link caption is caption with the partial URL substituted for `%s` – in the above example, the link caption would be `issue 123`.

  To produce a literal `%` in either base URL or caption, use `%%`:

      extlinks = {'KnR': ('https://example.org/K%%26R/page/%s',
                            '[K&R; page %s]')}

  You can also use the usual “explicit title” syntax supported by other roles that generate links, i.e. `:issue:`this issue <123>``. In this case, the caption is not relevant.

  Changed in version 4.0: Support to substitute by ‘%s’ in the caption.

Note

Since links are generated from the role in the reading stage, they appear as ordinary links to e.g. the `linkcheck` builder.

extlinks_detect_hardcoded_links
  Type:
    `bool`
  Default:
    `False`

  If enabled, extlinks emits a warning if a hardcoded link is replaceable by an extlink, and suggests a replacement via warning.

  Added in version 4.5.