Internal links & deep linking

🔗Heading id and anchor insertion

While rendering the Markdown content, a unique id will automatically be assigned to each heading. This id is created by converting the heading text to a slug if slugify.anchors is set to "on" (the default). If slugify.paths is set to "safe", whitespaces are replaced by _ and the following characters are stripped: #, %, <, >, [, ], (, ), `, ^, {, |, }. If slugify.paths is set to "off", no modifications are made, and you may be left with nominally illegal ids. A number is appended at the end if the slug already exists for that article. For example:

# Something exciting! <- something-exciting
## Example code <- example-code

# Something else <- something-else
## Example code <- example-code-1

You can also manually specify an id with a {#…} suffix on the heading line as well as CSS classes:

# Something manual! {#manual .header .bold}

This is useful for making deep links robust, either proactively (so that you can later change the text of a heading without breaking links to it) or retroactively (keeping the slug of the old header text when changing the text). It can also be useful for migration of existing sites with different header id schemes, so that you can keep deep links working.

🔗Anchor insertion

It is possible to have Zola automatically insert anchor links next to the heading, as you can see on this documentation if you hover a title or covering the full heading text.

This option is set at the section level: the insert_anchor_links variable on the section front matter page.

The default template is very basic and will need CSS tweaks in your project to look decent. If you want to change the anchor template, it can be easily overwritten by creating an anchor-link.html file in the templates directory. Here you can find the default template.

The anchor link template has the following variables:

  • id: the heading's id after applying the rules defined by slugify.anchors
  • lang: the current language, unless called from the markdown template filter, in which case it will always be en
  • level: the heading level (between 1 and 6)

If you use insert_anchor = "heading", the template will still be used but only the opening <a> tag will get extracted from it, everything else will not be used.

Linking to other pages and their headings is so common that Zola adds a special syntax to Markdown links to handle them: start the link with @/ and point to the .md file you want to link to. The path to the file starts from the content directory.

For example, linking to a file located at content/pages/about.md would be [my link](@/pages/about.md). You can still link to an anchor directly; [my link](@/pages/about.md#example) will work as expected.

By default, broken internal links are treated as errors. To treat them as warnings instead, visit the [link_checker] section of config.toml and set internal_level = "warn". Note: treating broken links as warnings allows the site to be built with broken links intact, so a link such as [my link](@/pages/whoops.md) will be rendered to HTML as <a href="@/pages/whoops.md">.