hugo/docs/content/en/content-management/page-resources.md
2025-08-23 12:39:28 +02:00

300 lines
10 KiB
Markdown

---
title: Page resources
description: Use page resources to logically associate assets with a page.
categories: []
keywords: []
---
Page resources are only accessible from [page bundles](/content-management/page-bundles), those directories with `index.md` or
`_index.md` files at their root. Page resources are only available to the
page with which they are bundled.
In this example, `first-post` is a page bundle with access to 10 page resources including audio, data, documents, images, and video. Although `second-post` is also a page bundle, it has no page resources and is unable to directly access the page resources associated with `first-post`.
```text
content
└── post
├── first-post
│ ├── images
│ │ ├── a.jpg
│ │ ├── b.jpg
│ │ └── c.jpg
│ ├── index.md (root of page bundle)
│ ├── latest.html
│ ├── manual.json
│ ├── notice.md
│ ├── office.mp3
│ ├── pocket.mp4
│ ├── rating.pdf
│ └── safety.txt
└── second-post
└── index.md (root of page bundle)
```
## Examples
Use any of these methods on a `Page` object to capture page resources:
- [`Resources.ByType`]
- [`Resources.Get`]
- [`Resources.GetMatch`]
- [`Resources.Match`]
Once you have captured a resource, use any of the applicable [`Resource`] methods to return a value or perform an action.
The following examples assume this content structure:
```text
content/
└── example/
├── data/
│ └── books.json <-- page resource
├── images/
│ ├── a.jpg <-- page resource
│ └── b.jpg <-- page resource
├── snippets/
│ └── text.md <-- page resource
└── index.md
```
Render a single image, and throw an error if the file does not exist:
```go-html-template
{{ $path := "images/a.jpg" }}
{{ with .Resources.Get $path }}
<img src="{{ .RelPermalink }}" width="{{ .Width }}" height="{{ .Height }}" alt="">
{{ else }}
{{ errorf "Unable to get page resource %q" $path }}
{{ end }}
```
Render all images, resized to 300 px wide:
```go-html-template
{{ range .Resources.ByType "image" }}
{{ with .Resize "300x" }}
<img src="{{ .RelPermalink }}" width="{{ .Width }}" height="{{ .Height }}" alt="">
{{ end }}
{{ end }}
```
Render the markdown snippet:
```go-html-template
{{ with .Resources.Get "snippets/text.md" }}
{{ .Content }}
{{ end }}
```
List the titles in the data file, and throw an error if the file does not exist.
```go-html-template
{{ $path := "data/books.json" }}
{{ with .Resources.Get $path }}
{{ with . | transform.Unmarshal }}
<p>Books:</p>
<ul>
{{ range . }}
<li>{{ .title }}</li>
{{ end }}
</ul>
{{ end }}
{{ else }}
{{ errorf "Unable to get page resource %q" $path }}
{{ end }}
```
## Metadata
The page resources' metadata is managed from the corresponding page's front matter with an array/table parameter named `resources`. You can batch assign values using [wildcards](https://tldp.org/LDP/GNU-Linux-Tools-Summary/html/x11655.htm).
> [!note]
> Resources of type `page` get `Title` etc. from their own front matter.
name
: (`string`) Sets the value returned in `Name`.
> [!note]
> The methods `Match`, `Get` and `GetMatch` use `Name` to match the resources.
title
: (`string`) Sets the value returned in `Title`
params
: (`map`) A map of custom key-value pairs.
### Resources metadata example
<!-- markdownlint-disable MD007 MD032 -->
{{< code-toggle file=content/example.md fm=true >}}
title: Application
date: 2018-01-25
resources:
- src: images/sunset.jpg
name: header
- src: documents/photo_specs.pdf
title: Photo Specifications
params:
icon: photo
- src: documents/guide.pdf
title: Instruction Guide
- src: documents/checklist.pdf
title: Document Checklist
- src: documents/payment.docx
title: Proof of Payment
- src: "**.pdf"
name: pdf-file-:counter
params:
icon: pdf
- src: "**.docx"
params:
icon: word
{{</ code-toggle >}}
<!-- markdownlint-enable MD007 MD032 -->
From the example above:
- `sunset.jpg` will receive a new `Name` and can now be found with `.GetMatch "header"`.
- `documents/photo_specs.pdf` will get the `photo` icon.
- `documents/checklist.pdf`, `documents/guide.pdf` and `documents/payment.docx` will get `Title` as set by `title`.
- Every `PDF` in the bundle except `documents/photo_specs.pdf` will get the `pdf` icon.
- All `PDF` files will get a new `Name`. The `name` parameter contains a special placeholder [`:counter`](#the-counter-placeholder-in-name-and-title), so the `Name` will be `pdf-file-1`, `pdf-file-2`, `pdf-file-3`.
- Every docx in the bundle will receive the `word` icon.
> [!note]
> The order matters; only the first set values of the `title`, `name` and `params` keys will be used. Consecutive parameters will be set only for the ones not already set. In the above example, `.Params.icon` is first set to `"photo"` in `src = "documents/photo_specs.pdf"`. So that would not get overridden to `"pdf"` by the later set `src = "**.pdf"` rule.
### The `:counter` placeholder in `name` and `title`
The `:counter` is a special placeholder recognized in `name` and `title` parameters `resources`.
The counter starts at 1 the first time they are used in either `name` or `title`.
For example, if a bundle has the resources `photo_specs.pdf`, `other_specs.pdf`, `guide.pdf` and `checklist.pdf`, and the front matter has specified the `resources` as:
{{< code-toggle file=content/inspections/engine/index.md fm=true >}}
title = 'Engine inspections'
[[resources]]
src = "*specs.pdf"
title = "Specification #:counter"
[[resources]]
src = "**.pdf"
name = "pdf-file-:counter"
{{</ code-toggle >}}
the `Name` and `Title` will be assigned to the resource files as follows:
| Resource file | `Name` | `Title` |
|-------------------|-------------------|-----------------------|
| checklist.pdf | `"pdf-file-1.pdf` | `"checklist.pdf"` |
| guide.pdf | `"pdf-file-2.pdf` | `"guide.pdf"` |
| other\_specs.pdf | `"pdf-file-3.pdf` | `"Specification #1"` |
| photo\_specs.pdf | `"pdf-file-4.pdf` | `"Specification #2"` |
## Multilingual
{{< new-in 0.123.0 />}}
By default, with a multilingual single-host site, Hugo does not duplicate shared page resources when building the site.
> [!note]
> This behavior is limited to Markdown content. Shared page resources for other [content formats] are copied into each language bundle.
Consider this site configuration:
{{< code-toggle file=hugo >}}
defaultContentLanguage = 'de'
defaultContentLanguageInSubdir = true
[languages.de]
languageCode = 'de-DE'
languageName = 'Deutsch'
weight = 1
[languages.en]
languageCode = 'en-US'
languageName = 'English'
weight = 2
{{< /code-toggle >}}
And this content:
```text
content/
└── my-bundle/
├── a.jpg <-- shared page resource
├── b.jpg <-- shared page resource
├── c.de.jpg
├── c.en.jpg
├── index.de.md
└── index.en.md
```
With v0.122.0 and earlier, Hugo duplicated the shared page resources, creating copies for each language:
```text
public/
├── de/
│ ├── my-bundle/
│ │ ├── a.jpg <-- shared page resource
│ │ ├── b.jpg <-- shared page resource
│ │ ├── c.de.jpg
│ │ └── index.html
│ └── index.html
├── en/
│ ├── my-bundle/
│ │ ├── a.jpg <-- shared page resource (duplicate)
│ │ ├── b.jpg <-- shared page resource (duplicate)
│ │ ├── c.en.jpg
│ │ └── index.html
│ └── index.html
└── index.html
```
With v0.123.0 and later, Hugo places the shared resources in the page bundle for the default content language:
```text
public/
├── de/
│ ├── my-bundle/
│ │ ├── a.jpg <-- shared page resource
│ │ ├── b.jpg <-- shared page resource
│ │ ├── c.de.jpg
│ │ └── index.html
│ └── index.html
├── en/
│ ├── my-bundle/
│ │ ├── c.en.jpg
│ │ └── index.html
│ └── index.html
└── index.html
```
This approach reduces build times, storage requirements, bandwidth consumption, and deployment times, ultimately reducing cost.
> [!important]
> To resolve Markdown link and image destinations to the correct location, you must use link and image render hooks that capture the page resource with the [`Resources.Get`] method, and then invoke its [`RelPermalink`] method.
>
> In its default configuration, Hugo automatically uses the [embedded link render hook] and the [embedded image render hook] for multilingual single-host sites, specifically when the [duplication of shared page resources] feature is disabled. This is the default behavior for such sites. If custom link or image render hooks are defined by your project, modules, or themes, these will be used instead.
>
> You can also configure Hugo to `always` use the embedded link or image render hook, use it only as a `fallback`, or `never` use it. See&nbsp;[details](/configuration/markup/#renderhookslinkuseembedded).
Although duplicating shared page resources is inefficient, you can enable this feature in your site configuration if desired:
{{< code-toggle file=hugo >}}
[markup.goldmark]
duplicateResourceFiles = true
{{< /code-toggle >}}
[`RelPermalink`]: /methods/resource/relpermalink/
[`Resource`]: /methods/resource
[`Resources.ByType`]: /methods/page/resources#bytype
[`Resources.Get`]: /methods/page/resources/#get
[`Resources.GetMatch`]: /methods/page/resources#getmatch
[`Resources.Match`]: /methods/page/resources#match
[content formats]: /content-management/formats/
[duplication of shared page resources]: /configuration/markup/#duplicateresourcefiles
[embedded image render hook]: /render-hooks/images/#embedded
[embedded link render hook]: /render-hooks/links/#embedded