hugo/docs/content/en/content-management/front-matter.md
2024-02-07 20:46:41 +01:00

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---
title: Front matter
description: Hugo allows you to add front matter in yaml, toml, or json to your content files.
categories: [content management]
keywords: [front matter,yaml,toml,json,metadata,archetypes]
menu:
docs:
parent: content-management
weight: 60
weight: 60
toc: true
aliases: [/content/front-matter/]
---
**Front matter** allows you to keep metadata attached to an instance of a [content type]---i.e., embedded inside a content file---and is one of the many features that gives Hugo its strength.
{{< youtube Yh2xKRJGff4 >}}
## Front matter formats
Hugo supports four formats for front matter, each with their own identifying tokens.
TOML
: identified by opening and closing `+++`.
YAML
: identified by opening and closing `---`.
JSON
: a single JSON object surrounded by '`{`' and '`}`', followed by a new line.
ORG
: a group of Org mode keywords in the format '`#+KEY: VALUE`'. Any line that does not start with `#+` ends the front matter section.
Array values can either be separated into multiple lines (`#+KEY: VALUE_1` and `#+KEY: VALUE_2`) or a whitespace separated list of strings (`#+KEY[]: VALUE_1 VALUE_2`).
### Example
{{< code-toggle >}}
title = "spf13-vim 3.0 release and new website"
description = "spf13-vim is a cross platform distribution of vim plugins and resources for Vim."
tags = [ ".vimrc", "plugins", "spf13-vim", "vim" ]
date = "2012-04-06"
categories = [
"Development",
"VIM"
]
slug = "spf13-vim-3-0-release-and-new-website"
{{< /code-toggle >}}
## Front matter variables
### Predefined
There are a few predefined variables that Hugo is aware of. See [Page Variables][pagevars] for how to call many of these predefined variables in your templates.
aliases
: An array of one or more aliases (e.g., old published paths of renamed content) that will be created in the output directory structure . See [Aliases][aliases] for details.
audio
: An array of paths to audio files related to the page; used by the `opengraph` [internal template](/templates/internal) to populate `og:audio`.
cascade
: A map of front matter keys whose values are passed down to the page's descendants unless overwritten by self or a closer ancestor's cascade. See [Front Matter Cascade](#front-matter-cascade) for details.
date
: The datetime assigned to this page. This is usually fetched from the `date` field in front matter, but this behavior is configurable.
description
: The description for the content.
draft
: If `true`, the content will not be rendered unless the `--buildDrafts` flag is passed to the `hugo` command.
expiryDate
: The datetime at which the content should no longer be published by Hugo; expired content will not be rendered unless the `--buildExpired` flag is passed to the `hugo` command.
headless
: If `true`, sets a leaf bundle to be [headless][headless-bundle].
images
: An array of paths to images related to the page; used by [internal templates](/templates/internal) such as `_internal/twitter_cards.html`.
isCJKLanguage
: If `true`, Hugo will explicitly treat the content as a CJK language; both `.Summary` and `.WordCount` work properly in CJK languages.
keywords
: The meta keywords for the content.
layout
: The layout Hugo should select from the [lookup order][lookup] when rendering the content. If a `type` is not specified in the front matter, Hugo will look for the layout of the same name in the layout directory that corresponds with a content's section. See [Content Types][content type].
lastmod
: The datetime at which the content was last modified.
linkTitle
: Used for creating links to content; if set, Hugo defaults to using the `linkTitle` before the `title`.
markup
: **experimental**; specify `"rst"` for reStructuredText (requires`rst2html`) or `"md"` (default) for Markdown.
outputs
: Allows you to specify output formats specific to the content. See [output formats][outputs].
publishDate
: If in the future, content will not be rendered unless the `--buildFuture` flag is passed to `hugo`.
resources
: Used for configuring page bundle resources. See [Page Resources][page-resources].
series
: An array of series this page belongs to, as a subset of the `series` [taxonomy](/content-management/taxonomies/); used by the `opengraph` [internal template](/templates/internal) to populate `og:see_also`.
slug
: Overrides the last segment of the URL path. Not applicable to section pages. See [URL Management](/content-management/urls/#slug) for details.
summary
: Text used when providing a summary of the article in the `.Summary` page variable; details available in the [content-summaries](/content-management/summaries/) section.
title
: The title for the content.
type
: The type of the content; this value will be automatically derived from the directory (i.e., the [section]) if not specified in front matter.
url
: Overrides the entire URL path. Applicable to regular pages and section pages. See [URL Management](/content-management/urls/#url) for details.
videos
: An array of paths to videos related to the page; used by the `opengraph` [internal template](/templates/internal) to populate `og:video`.
weight
: used for [ordering your content in lists][ordering]. Lower weight gets higher precedence. So content with lower weight will come first. If set, weights should be non-zero, as 0 is interpreted as an *unset* weight.
{{% note %}}
If neither `slug` nor `url` is present and [permalinks are not configured otherwise in your site configuration file](/content-management/urls/#permalinks), Hugo will use the file name of your content to create the output URL. See [Content Organization](/content-management/organization) for an explanation of paths in Hugo and [URL Management](/content-management/urls/) for ways to customize Hugo's default behaviors.
{{% /note %}}
### User-defined
You can add fields to your front matter arbitrarily to meet your needs. These user-defined key-values are placed into a single `.Params` variable for use in your templates.
The following fields can be accessed via `.Params.include_toc` and `.Params.show_comments`, respectively. The [Variables] section provides more information on using Hugo's page- and site-level variables in your templates.
{{< code-toggle >}}
include_toc: true
show_comments: false
{{</ code-toggle >}}
## Front matter cascade
Any node or section can pass down to descendants a set of front matter values as long as defined underneath the reserved `cascade` front matter key.
### Target specific pages
The `cascade` block can be a slice with a optional `_target` keyword, allowing for multiple `cascade` values targeting different page sets.
{{< code-toggle >}}
title ="Blog"
[[cascade]]
background = "yosemite.jpg"
[cascade._target]
path="/blog/**"
lang="en"
kind="page"
[[cascade]]
background = "goldenbridge.jpg"
[cascade._target]
kind="section"
{{</ code-toggle >}}
Keywords available for `_target`:
path
: A [Glob](https://github.com/gobwas/glob) pattern matching the content path below /content. Expects Unix-styled slashes. Note that this is the virtual path, so it starts at the mount root. The matching supports double-asterisks so you can match for patterns like `/blog/*/**` to match anything from the third level and down.
kind
: A Glob pattern matching the Page's Kind(s), e.g. "{home,section}".
lang
: A Glob pattern matching the Page's language, e.g. "{en,sv}".
environment
: A Glob pattern matching the build environment, e.g. "{production,development}"
Any of the above can be omitted.
{{% note %}}
When making a site that supports multiple languages, defining a `[[cascade]]` is recommended to be done in [Site Config](../../getting-started/configuration/#cascade) to prevent duplication.
If you instead define a `[[cascade]]` in front matter for multiple languages, an `content/XX/foo/_index.md` file needs to be made on a per-language basis, with `XX` the glob pattern matching the Page's language. In this case, the **lang** keyword is ignored.
{{% /note %}}
### Example
In `content/blog/_index.md`
{{< code-toggle >}}
title: Blog
cascade:
banner: images/typewriter.jpg
{{</ code-toggle >}}
With the above example the Blog section page and its descendants will return `images/typewriter.jpg` when `.Params.banner` is invoked unless:
- Said descendant has its own `banner` value set
- Or a closer ancestor node has its own `cascade.banner` value set.
## Order content through front matter
You can assign content-specific `weight` in the front matter of your content. These values are especially useful for [ordering][ordering] in list views. You can use `weight` for ordering of content and the convention of [`<TAXONOMY>_weight`][taxweight] for ordering content within a taxonomy. See [Ordering and Grouping Hugo Lists][lists] to see how `weight` can be used to organize your content in list views.
## Override global markdown configuration
It's possible to set some options for Markdown rendering in a content's front matter as an override to the [rendering options set in your project configuration][config].
## Front matter format specs
- [TOML Spec][toml]
- [YAML Spec][yaml]
- [JSON Spec][json]
[variables]: /variables/
[aliases]: /content-management/urls/#aliases
[archetype]: /content-management/archetypes/
[config]: /getting-started/configuration/
[content type]: /content-management/types/
[contentorg]: /content-management/organization/
[headless-bundle]: /content-management/page-bundles/#headless-bundle
[json]: https://www.ecma-international.org/publications/files/ECMA-ST/ECMA-404.pdf
[lists]: /templates/lists/#sort-content
[lookup]: /templates/lookup-order/
[ordering]: /templates/lists/
[outputs]: /templates/output-formats/
[page-resources]: /content-management/page-resources/
[pagevars]: /variables/page/
[section]: /content-management/sections/
[taxweight]: /content-management/taxonomies/
[toml]: https://toml.io/
[urls]: /content-management/urls/
[variables]: /variables/
[yaml]: https://yaml.org/spec/