hugo/docs/content/en/templates/lists.md
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Lists of Content in Hugo List Page Templates Lists have a specific meaning and usage in Hugo when it comes to rendering your site homepage, section page, taxonomy list, or taxonomy terms list. 2017-02-01 2017-02-01 2017-02-01
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What is a List Page Template?

{{< youtube 8b2YTSMdMps >}}

A list page template is a template used to render multiple pieces of content in a single HTML page. The exception to this rule is the homepage, which is still a list but has its own dedicated template.

Hugo uses the term list in its truest sense; i.e. a sequential arrangement of material, especially in alphabetical or numerical order. Hugo uses list templates on any output HTML page where content is traditionally listed:

For template lookup order, see Template Lookup.

The idea of a list page comes from the hierarchical mental model of the web and is best demonstrated visually:

Image demonstrating a hierarchical website sitemap.

List Defaults

Default Templates

Since section lists and taxonomy lists (N.B., not taxonomy terms lists) are both lists with regards to their templates, both have the same terminating default of _default/list.html or themes/<THEME>/layouts/_default/list.html in their lookup order. In addition, both section lists and taxonomy lists have their own default list templates in _default:

See Template Lookup Order for the complete reference.

Add Content and Front Matter to List Pages

Since v0.18, everything in Hugo is a Page. This means list pages and the homepage can have associated content files (i.e. _index.md) that contain page metadata (i.e., front matter) and content.

This new model allows you to include list-specific front matter via .Params and also means that list templates (e.g., layouts/_default/list.html) have access to all page variables.

{{% note %}} It is important to note that all _index.md content files will render according to a list template and not according to a single page template. {{% /note %}}

Example Project Directory

The following is an example of a typical Hugo project directory's content:

.
...
├── content
|   ├── post
|   |   ├── _index.md
|   |   ├── post-01.md
|   |   └── post-02.md
|   └── quote
|   |   ├── quote-01.md
|   |   └── quote-02.md
...

Using the above example, let's assume you have the following in content/post/_index.md:

{{< code file="content/post/_index.md" >}}

title: My Go Journey date: 2017-03-23 publishdate: 2017-03-24

I decided to start learning Go in March 2017.

Follow my journey through this new blog. {{< /code >}}

You can now access this _index.md's' content in your list template:

{{< code file="layouts/_default/list.html" download="list.html" >}} {{ define "main" }}

{{.Title}}

{{.Content}}
{{ end }} {{< /code >}}

This above will output the following HTML:

{{< code file="example.com/post/index.html" copy="false" >}}

My Go Journey

I decided to start learning Go in March 2017.

Follow my journey through this new blog.

{{< /code >}}

List Pages Without _index.md

You do not have to create an _index.md file for every list page (i.e. section, taxonomy, taxonomy terms, etc) or the homepage. If Hugo does not find an _index.md within the respective content section when rendering a list template, the page will be created but with no {{.Content}} and only the default values for .Title etc.

Using this same layouts/_default/list.html template and applying it to the quotes section above will render the following output. Note that quotes does not have an _index.md file to pull from:

{{< code file="example.com/quote/index.html" copy="false" >}}

Quotes

{{< /code >}}

{{% note %}} The default behavior of Hugo is to pluralize list titles; hence the inflection of the quote section to "Quotes" when called with the .Title page variable. You can change this via the pluralizeListTitles directive in your site configuration. {{% /note %}}

Example List Templates

Section Template

This list template has been modified slightly from a template originally used in spf13.com. It makes use of partial templates for the chrome of the rendered page rather than using a base template The examples that follow also use the content view templates li.html or summary.html.

{{< code file="layouts/section/post.html" >}} {{ partial "header.html" . }} {{ partial "subheader.html" . }}

{{ .Title }}

    {{ range .Pages }} {{ .Render "li"}} {{ end }}
{{ partial "footer.html" . }} {{< /code >}}

Taxonomy Template

{{< code file="layouts/_default/taxonomy.html" download="taxonomy.html" >}} {{ define "main" }}

{{ .Title }}

{{ range .Pages }} {{ .Render "summary"}} {{ end }}
{{ end }} {{< /code >}}

Order Content

Hugo lists render the content based on metadata you provide in front matter. In addition to sane defaults, Hugo also ships with multiple methods to make quick work of ordering content inside list templates:

Default: Weight > Date > LinkTitle > FilePath

{{< code file="layouts/partials/default-order.html" >}}

    {{ range .Pages }}
  • {{ .Title }}

  • {{ end }}
{{< /code >}}

By Weight

Lower weight gets higher precedence. So content with lower weight will come first.

{{< code file="layouts/partials/by-weight.html" >}}

    {{ range .Pages.ByWeight }}
  • {{ .Title }}

  • {{ end }}
{{< /code >}}

By Date

{{< code file="layouts/partials/by-date.html" >}}

    {{ range .Pages.ByDate }}
  • {{ .Title }}

  • {{ end }}
{{< /code >}}

By Publish Date

{{< code file="layouts/partials/by-publish-date.html" >}}

    {{ range .Pages.ByPublishDate }}
  • {{ .Title }}

  • {{ end }}
{{< /code >}}

By Expiration Date

{{< code file="layouts/partials/by-expiry-date.html" >}}

    {{ range .Pages.ByExpiryDate }}
  • {{ .Title }}

  • {{ end }}
{{< /code >}}

By Last Modified Date

{{< code file="layouts/partials/by-last-mod.html" >}}

    {{ range .Pages.ByLastmod }}
  • {{ .Title }}

  • {{ end }}
{{< /code >}}

By Length

{{< code file="layouts/partials/by-length.html" >}}

    {{ range .Pages.ByLength }}
  • {{ .Title }}

  • {{ end }}
{{< /code >}}

By Title

{{< code file="layouts/partials/by-title.html" >}}

    {{ range .Pages.ByTitle }}
  • {{ .Title }}

  • {{ end }}
{{< /code >}}

{{< code file="layouts/partials/by-link-title.html" >}}

    {{ range .Pages.ByLinkTitle }}
  • {{ .LinkTitle }}

  • {{ end }}
{{< /code >}}

By Parameter

Order based on the specified front matter parameter. Content that does not have the specified front matter field will use the site's .Site.Params default. If the parameter is not found at all in some entries, those entries will appear together at the end of the ordering.

{{< code file="layouts/partials/by-rating.html" >}}

{{ range (.Pages.ByParam "rating") }}

{{ end }} {{< /code >}}

If the targeted front matter field is nested beneath another field, you can access the field using dot notation.

{{< code file="layouts/partials/by-nested-param.html" >}} {{ range (.Pages.ByParam "author.last_name") }}

{{ end }} {{< /code >}}

Reverse Order

Reversing order can be applied to any of the above methods. The following uses ByDate as an example:

{{< code file="layouts/partials/by-date-reverse.html" >}}

    {{ range .Pages.ByDate.Reverse }}
  • {{ .Title }}

  • {{ end }}
{{< /code >}}

Group Content

Hugo provides some functions for grouping pages by Section, Type, Date, etc.

By Page Field

{{< code file="layouts/partials/by-page-field.html" >}}

{{ range .Pages.GroupBy "Section" }}

{{ .Key }}

    {{ range .Pages }}
  • {{ .Title }}
    {{ .Date.Format "Mon, Jan 2, 2006" }}
  • {{ end }}
{{ end }} {{< /code >}}

In the above example, you may want {{.Title}} to point the title field you have added to your _index.md file instead. You can access this value using the .GetPage function:

{{< code file="layouts/partials/by-page-field.html" >}}

{{ range .Pages.GroupBy "Section" }}

{{ with $.Site.GetPage "section" .Key }}

{{.Title}}

{{ else }}

{{ .Key | title }}

{{ end }}
    {{ range .Pages }}
  • {{ .Title }}
    {{ .Date.Format "Mon, Jan 2, 2006" }}
  • {{ end }}
{{ end }} {{< /code >}}

By Date

{{< code file="layouts/partials/by-page-date.html" >}}

{{ range .Pages.GroupByDate "2006-01" }}

{{ .Key }}

    {{ range .Pages }}
  • {{ .Title }}
    {{ .Date.Format "Mon, Jan 2, 2006" }}
  • {{ end }}
{{ end }} {{< /code >}}

By Publish Date

{{< code file="layouts/partials/by-page-publish-date.html" >}}

{{ range .Pages.GroupByPublishDate "2006-01" }}

{{ .Key }}

    {{ range .Pages }}
  • {{ .Title }}
    {{ .PublishDate.Format "Mon, Jan 2, 2006" }}
  • {{ end }}
{{ end }} {{< /code >}}

By Page Parameter

{{< code file="layouts/partials/by-page-param.html" >}}

{{ range .Pages.GroupByParam "param_key" }}

{{ .Key }}

    {{ range .Pages }}
  • {{ .Title }}
    {{ .Date.Format "Mon, Jan 2, 2006" }}
  • {{ end }}
{{ end }} {{< /code >}}

By Page Parameter in Date Format

The following template takes grouping by date a step further and uses Go's layout string. See the Format function for more examples of how to use Go's layout string to format dates in Hugo.

{{< code file="layouts/partials/by-page-param-as-date.html" >}}

{{ range .Pages.GroupByParamDate "param_key" "2006-01" }}

{{ .Key }}

    {{ range .Pages }}
  • {{ .Title }}
    {{ .Date.Format "Mon, Jan 2, 2006" }}
  • {{ end }}
{{ end }} {{< /code >}}

Reverse Key Order

Ordering of groups is performed by keys in alphanumeric order (AZ, 1100) and in reverse chronological order (i.e., with the newest first) for dates.

While these are logical defaults, they are not always the desired order. There are two different syntaxes to change Hugo's default ordering for groups, both of which work the same way.

1. Adding the Reverse Method

{{ range (.Pages.GroupBy "Section").Reverse }}
{{ range (.Pages.GroupByDate "2006-01").Reverse }}

2. Providing the Alternate Direction

{{ range .Pages.GroupByDate "2006-01" "asc" }}
{{ range .Pages.GroupBy "Section" "desc" }}

Order Within Groups

Because Grouping returns a {{.Key}} and a slice of pages, all of the ordering methods listed above are available.

Here is the ordering for the example that follows:

  1. Content is grouped by month according to the date field in front matter.
  2. Groups are listed in ascending order (i.e., the oldest groups first)
  3. Pages within each respective group are ordered alphabetically according to the title.

{{< code file="layouts/partials/by-group-by-page.html" >}} {{ range .Pages.GroupByDate "2006-01" "asc" }}

{{ .Key }}

    {{ range .Pages.ByTitle }}
  • {{ .Title }}
    {{ .Date.Format "Mon, Jan 2, 2006" }}
  • {{ end }}
{{ end }} {{< /code >}}

Filter and Limiting Lists

Sometimes you only want to list a subset of the available content. A common is to only display “Posts” on blog's homepage. You can accomplish this with the where function.

where

where works in a similar manner to the where keyword in SQL. It selects all elements of the array or slice that match the provided field and value. where takes three arguments:

  1. array or slice of maps or structs
  2. key or field name
  3. match value

{{< code file="layouts/_default/index.html" >}} {{ range where .Pages "Section" "post" }} {{ .Content }} {{ end }} {{< /code >}}

You can see more examples in the functions documentation for where.

first

first works in a similar manner to the limit keyword in SQL. It reduces the array to only the first N elements. It takes the array and number of elements as input. first takes two arguments:

  1. array or slice of maps or structs
  2. number of elements

{{< code file="layout/_default/section.html" >}} {{ range first 10 .Pages }} {{ .Render "summary" }} {{ end }} {{< /code >}}

first and where Together

Using first and where together can be very powerful:

{{< code file="first-and-where-together.html" >}}

{{ range first 5 (where .Pages "Section" "post").ByTitle }} {{ .Content }} {{ end }} {{< /code >}}