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wagtail/docs/reference/jinja2.md

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(jinja2)=
# Jinja2 template support
Wagtail supports Jinja2 templating for all front end features. More information on each of the template tags below can be found in the [](writing_templates) documentation.
## Configuring Django
Django needs to be configured to support Jinja2 templates. As the Wagtail admin is written using standard Django templates, Django has to be configured to use **both** templating engines. Add the Jinja2 template backend configuration to the `TEMPLATES` setting for your app as shown here:
```python
TEMPLATES = [
{
"BACKEND": "django.template.backends.django.DjangoTemplates",
# ... the rest of the existing Django template configuration ...
},
{
'BACKEND': 'django.template.backends.jinja2.Jinja2',
'APP_DIRS': True,
'OPTIONS': {
'extensions': [
'wagtail.jinja2tags.core',
'wagtail.admin.jinja2tags.userbar',
'wagtail.images.jinja2tags.images',
],
},
}
]
```
Jinja templates must be placed in a `jinja2/` directory in your app. For example, the standard template location for an `EventPage` model in an `events` app would be `events/jinja2/events/event_page.html`.
By default, the Jinja environment does not have any Django functions or filters. The Django documentation has more information on {class}`django.template.backends.jinja2.Jinja2` (configuring Jinja for Django).
## `self` in templates
In Django templates, `self` can be used to refer to the current page, stream block, or field panel. In Jinja, `self` is reserved for internal use. When writing Jinja templates, use `page` to refer to pages, `value` for stream blocks, and `field_panel` for field panels.
## Template tags, functions & filters
### `fullpageurl()`
Generate an absolute URL (`http://example.com/foo/bar/`) for a Page instance:
```html+jinja
<meta property="og:url" content="{{ fullpageurl(page) }}" />
```
See [](fullpageurl_tag) for more information.
### `pageurl()`
Generate a URL (`/foo/bar/`) for a Page instance:
```html+jinja
<a href="{{ pageurl(page.more_information) }}">More information</a>
```
See [](pageurl_tag) for more information
### `slugurl()`
Generate a URL for a Page with a slug:
```html+jinja
<a href="{{ slugurl("about") }}">About us</a>
```
See [](slugurl_tag) for more information
### `image()`
Resize an image, and render an `<img>` tag:
```html+jinja
{{ image(page.header_image, "fill-1024x200", class="header-image") }}
```
Or resize an image and retrieve the resized image object (rendition) for more bespoke use:
```html+jinja
{% set background=image(page.background_image, "max-1024x1024") %}
<div class="wrapper" style="background-image: url({{ background.url }});"></div>
```
See [](image_tag) for more information
### `srcset_image()`
Resize an image, and render an `<img>` tag including `srcset` with multiple sizes.
Browsers will select the most appropriate image to load based on [responsive image rules](https://developer.mozilla.org/en-US/docs/Learn/HTML/Multimedia_and_embedding/Responsive_images).
The [`sizes`](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/img#sizes) attribute is essential unless you store the output of `srcset_image` for later use.
```html+jinja
{{ srcset_image(page.photo, "width-{400,800}", sizes="(max-width: 600px) 400px, 80vw") }}
```
This outputs:
```html
<img srcset="/media/images/pied-wagtail.width-400.jpg 400w, /media/images/pied-wagtail.width-800.jpg 800w" src="/media/images/pied-wagtail.width-400.jpg" alt="A pied Wagtail" sizes="(max-width: 600px) 400px, 80vw" width="400" height="300">
```
Or resize an image and retrieve the renditions for more bespoke use:
```html+jinja
{% set bg=srcset_image(page.background_image, "max-{512x512,1024x1024}") %}
<div class="wrapper" style="background-image: image-set(url({{ bg.renditions[0].url }}) 1x, url({{ bg.renditions[1].url }}) 2x);"></div>
```
### `picture()`
Resize or convert an image, rendering a `<picture>` tag including multiple `source` formats with `srcset` for multiple sizes, and a fallback `<img>` tag.
Browsers will select the [first supported image format](https://web.dev/learn/design/picture-element/#image-formats), and pick a size based on [responsive image rules](https://developer.mozilla.org/en-US/docs/Learn/HTML/Multimedia_and_embedding/Responsive_images).
`picture` can render an image in multiple formats:
```html+jinja
{{ picture(page.photo, "format-{avif,webp,jpeg}|width-400") }}
```
This outputs:
```html
<picture>
<source srcset="/media/images/pied-wagtail.width-400.avif" type="image/avif">
<source srcset="/media/images/pied-wagtail.width-400.webp" type="image/webp">
<img src="/media/images/pied-wagtail.width-400.jpg" alt="A pied Wagtail" width="400" height="300">
</picture>
```
Or render multiple formats and multiple sizes like `srcset_image` does. The [`sizes`](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/img#sizes) attribute is essential when the picture tag renders images in multiple sizes:
```html+jinja
{{ picture(page.header_image, "format-{avif,webp,jpeg}|width-{400,800}", sizes="80vw") }}
```
This outputs:
```html
<picture>
<source sizes="80vw" srcset="/media/images/pied-wagtail.width-400.avif 400w, /media/images/pied-wagtail.width-800.avif 800w" type="image/avif">
<source sizes="80vw" srcset="/media/images/pied-wagtail.width-400.webp 400w, /media/images/pied-wagtail.width-800.webp 800w" type="image/webp">
<img sizes="80vw" srcset="/media/images/pied-wagtail.width-400.jpg 400w, /media/images/pied-wagtail.width-800.jpg 800w" src="/media/images/pied-wagtail.width-400.jpg" alt="A pied Wagtail" width="400" height="300">
</picture>
```
Or resize an image and retrieve the renditions for more bespoke use:
```html+jinja
{% set bg=picture(page.background_image, "format-{avif,jpeg}|max-{512x512,1024x1024}") %}
<div class="wrapper" style="background-image: image-set(url({{ bg.formats['avif'][0].url }}) 1x type('image/avif'), url({{ bg.formats['avif'][1].url }}) 2x type('image/avif'), url({{ bg.formats['jpeg'][0].url }}) 1x type('image/jpeg'), url({{ bg.formats['jpeg'][1].url }}) 2x type('image/jpeg'));"></div>
```
### `|richtext`
Transform Wagtail's internal HTML representation, expanding internal references to pages and images.
```html+jinja
{{ page.body|richtext }}
```
See [](rich_text_filter) for more information
### `wagtail_site`
Returns the Site object corresponding to the current request.
```html+jinja
{{ wagtail_site().site_name }}
```
See [](wagtail_site_tag) for more information
### `wagtailuserbar()`
Output the Wagtail contextual flyout menu for editing pages from the front end
```html+jinja
{{ wagtailuserbar() }}
```
See [](wagtailuserbar_tag) for more information
### `{% include_block %}`
Output the HTML representation for the stream content as a whole, as well as for each individual block.
Allows to pass template context (by default) to the StreamField template.
```html+jinja
{% include_block page.body %}
{% include_block page.body with context %} {# The same as the previous #}
{% include_block page.body without context %}
```
See [StreamField template rendering](streamfield_template_rendering) for more information.
```{note}
The ``{% include_block %}`` tag is designed to closely follow the syntax and behaviour
of Jinja's ``{% include %}``, so it does not implement the Django version's feature of
only passing specified variables into the context.
```