mkdocs-material/docs/setup/setting-up-social-cards.md
2023-05-08 16:44:39 +02:00

811 lines
26 KiB
Markdown
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

---
status: new
---
# Setting up social cards
Material for MkDocs can automatically create beautiful social cards for your
documentation, which appear as link previews on social media platforms. You
can select from several [pre-designed layouts][default layouts] or create
[custom layouts] to match your unique style and branding.
<figure markdown>
[![Layout default variant]][Layout default variant]
<figcaption markdown>
Social card of our [formatting] reference
</figcaption>
</figure>
[custom layouts]: #customization
[formatting]: ../reference/formatting.md
## Configuration
### Built-in social plugin
[:octicons-tag-24: 8.5.0][Social cards support] ·
:octicons-cpu-24: Plugin ·
:octicons-beaker-24: Experimental
The built-in social plugin automatically generate a custom preview image for
each page. Install all [dependencies for image processing][^1] and add the
following lines to `mkdocs.yml`:
[^1]:
The awesome thing about social cards is that they are generated during
build time and directly distributed with your documentation, no external
services involved. While it would technically be simpler to generate
social cards using a web browser and an automation framework like
[Puppeteer], it would add further liabilities to the toolchain, with the
potential to make build pipelines more complex and resource intense.
For this reason, Material for MkDocs again follows its core principle of
making it as simple and powerful as possible, providing an easy-to-use
framework for building [custom layouts] using Python image processing
libraries.
``` yaml
plugins:
- social
```
> Note that [Insiders] contains a ground up rewrite of the social plugin that
> generates images much more efficiently in parallel and allows to build
> entirely [custom layouts].
The following configuration options are available:
[`enabled`](#+social.enabled){ #+social.enabled }
: :octicons-milestone-24: Default: `true` This option specifies whether
the plugin is enabled when building your project. If you want to speed up
local builds, you can use an [environment variable]:
``` yaml
plugins:
- social:
enabled: !ENV [CI, false]
```
[`concurrency`](#+social.concurrency){ #+social.concurrency }
: [:octicons-tag-24: insiders-4.33.0][Insiders] · :octicons-milestone-24:
Default: _number of CPUs_ How many CPUs the plugin is allowed to use when
generating social cards. With more CPUs, the plugin can do more work in the
same time, thus complete generation faster. Concurrent processing can be
disabled with:
``` yaml
plugins:
- social:
concurrency: 1
```
[Social cards support]: https://github.com/squidfunk/mkdocs-material/releases/tag/8.5.0
[built-in plugins]: ../insiders/getting-started.md#built-in-plugins
[dependencies for image processing]: dependencies/image-processing.md
[Puppeteer]: https://github.com/puppeteer/puppeteer
[Insiders]: ../insiders/index.md
[environment variable]: https://www.mkdocs.org/user-guide/configuration/#environment-variables
#### Social cards
The following configuration options are available for card generation:
[`cards`](#+social.cards){ #+social.cards }
: :octicons-milestone-24: Default: `true` This option specifies whether
to generate social card images. If you want to switch the plugin off, e.g.
for local builds, you can use an [environment variable]:
``` yaml
plugins:
- social:
cards: !ENV [CI, false]
```
[`cards_dir`](#+social.cards_dir){ #+social.cards_dir }
: :octicons-milestone-24: Default: `assets/images/social` This option
specifies where the generated social cards will be stored. While it's
usually not necessary to change this option, change it with:
``` yaml
plugins:
- social:
cards_dir: assets/images/social
```
<div class="mdx-deprecated" markdown>
[`cards_color`](#+social.cards_color){ #+social.cards_color } <small>:material-trash-can: Deprecated, use [`cards_layout_options`][layout options]</small>
: :octicons-milestone-24: Default: [`theme.palette.primary`][primary color]
This option specifies the colors for the background `fill` and foreground
`text` when generating the social card:
``` yaml
plugins:
- social:
cards_color:
fill: "#0FF1CE"
text: "#FFFFFF"
```
[`cards_font`](#+social.cards_font){ #+social.cards_font } <small>:material-trash-can: Deprecated, use [`cards_layout_options`][layout options]</small>
: :octicons-milestone-24: Default: [`theme.font.text`][font] This option
specifies which font to use for rendering the social card, which can be
any font hosted on [Google Fonts]:
``` yaml
plugins:
- social:
cards_font: Ubuntu
```
</div>
[`cards_layout_dir`](#+social.cards_layout_dir){ #+social.cards_layout_dir }
: [:octicons-tag-24: insiders-4.33.0][Insiders] · :octicons-milestone-24:
Default: _none_ This option specifies where the social plugin should try
to resolve [custom layouts] from, taking precedence over the included
layouts:
``` yaml
plugins:
- social:
cards_layout_dir: layouts
```
[`cards_layout`](#+social.cards_layout){ #+social.cards_layout } :material-alert-decagram:{ .mdx-pulse title="Added on May 8, 2023" }
: [:octicons-tag-24: insiders-4.33.0][Insiders] · :octicons-milestone-24:
Default: `default` Layout specification the social card should use. The
plugin includes the following layouts which make use of the [color palette]
and [font]:
=== "`default`"
``` yaml
plugins:
- social:
cards_layout: default
```
This layout uses the configured [primary color] as a background:
[![Layout default]][Layout default]
=== "`default/variant`"
``` yaml
plugins:
- social:
cards_layout: default/variant
```
This layout includes the [page icon] as a watermark, if defined:
[![Layout default variant]][Layout default variant]
=== "`default/accent`"
``` yaml
plugins:
- social:
cards_layout: default/accent
```
This layout uses the configured [accent color] as a background:
[![Layout default accent]][Layout default accent]
=== "`default/invert`"
``` yaml
plugins:
- social:
cards_layout: default/invert
```
This layout inverts the background and foreground colors:
[![Layout default invert]][Layout default invert]
All [`default`][default layouts] layouts make use of the following
[template variables]:
- :material-page-layout-header: `config.site_name`
- :material-page-layout-body: `page.meta.title` or `page.title`
- :material-page-layout-footer: `page.meta.description` or `config.site_description`
- :material-page-layout-sidebar-right: `theme.logo` or `theme.icon.logo`
[`cards_layout_options`](#+social.cards_layout_options){ #+social.cards_layout_options }
: [:octicons-tag-24: insiders-4.33.0][Insiders] · :octicons-milestone-24:
Default: _none_ This option allows to set [parameters] as provided by
the layout specification. For [custom layouts], this key can be used to
provide layout-specific options, making layouts entirels configurable.
---
All [`default`][default layouts] layouts expose the following parameters:
[`background_color`](#+social.cards_layout_options.background_color){ #+social.cards_layout_options.background_color }
: Set a background color, which can be a [CSS color keyword], or a 3, 4, 6
or 8 letter HEX color code. Alpha channels are supported as well:
``` yaml
plugins:
- social:
cards_layout_options:
background_color: "#0FF1CE"
```
[`background_image`](#+social.cards_layout_options.background_image){ #+social.cards_layout_options.background_image }
: Set a background image. If a `background_color` is set, like for the
[`default`][default layouts] layouts, the image is tinted (overlayed)
with the color. Thus, the background color must be (partially)
transparent for the image to become visible:
``` yaml
plugins:
- social:
cards_layout_options:
background_color: "#00000000"
background_image: layouts/background.png
```
The path of the image must be defined relative to the project root.
[`color`](#+social.cards_layout_options.color){ #+social.cards_layout_options.color }
: Set a foreground color, which can be a [CSS color keyword], or a 3, 4, 6
or 8 letter HEX color code. The color is primarily used to tint text and
icons:
``` yaml
plugins:
- social:
cards_layout_options:
color: "#0FF1CE"
```
[`font_family`](#+social.cards_layout_options.font_family){ #+social.cards_layout_options.font_family }
: Set a font family. This overrides the [font] that is set as part of the
theme configuration. The [built-in social plugin] will automatically
download the font from [Google Fonts]:
``` yaml
plugins:
- social:
cards_layout_options:
font_family: Ubuntu
```
[color palette]: ./changing-the-colors.md#color-palette
[primary color]: ./changing-the-colors.md#primary-color
[accent color]: ./changing-the-colors.md#accent-color
[font]: ./changing-the-fonts.md#regular-font
[Google Fonts]: https://fonts.google.com/
[layout options]: #+social.cards_layout_options
[page icon]: ../reference/index.md#setting-the-page-icon
[Layout default]: ../assets/screenshots/social-cards.png
[Layout default variant]: ../assets/screenshots/social-cards-variant.png
[Layout default accent]: ../assets/screenshots/social-cards-accent.png
[Layout default invert]: ../assets/screenshots/social-cards-invert.png
[template variables]: https://www.mkdocs.org/dev-guide/themes/#template-variables
[parameters]: #parameters
[default layouts]: #+social.cards_layout
[CSS color keyword]: https://developer.mozilla.org/en-US/docs/Web/CSS/color_value#color_keywords
#### Debugging
The following configuration options are available for debugging:
[`debug`](#+social.debug){ #+social.debug }
: [:octicons-tag-24: insiders-4.33.0][Insiders] · :octicons-milestone-24:
Default: `false` This option enables a special debug mode, which renders
each layer with an outline and its `x` and `y` offset in order to understand
how the layout is composed, and optionally renders a grid for easier
alignment:
``` yaml
plugins:
- social:
debug: true
```
=== "With debug mode"
[![Debug mode enabled]][Debug mode enabled]
=== "Without"
[![Debug mode disabled]][Debug mode disabled]
[Debug mode enabled]: ../assets/screenshots/social-cards-debug.png
[Debug mode disabled]: ../assets/screenshots/social-cards-variant.png
[`debug_grid`](#+social.debug_grid){ #+social.debug_grid }
: [:octicons-tag-24: insiders-4.33.0][Insiders] · :octicons-milestone-24:
Default: `true` This option enables the rendering of a dot grid when
[`debug`][debug] is enabled (see screenshot above). The grid can be switched
off with:
``` yaml
plugins:
- social:
debug_grid: false
```
[`debug_grid_step`](#+social.debug_grid_step){ #+social.debug_grid_step }
: [:octicons-tag-24: insiders-4.33.0][Insiders] · :octicons-milestone-24:
Default: `32` This option specifies the step size of the grid in pixels,
if enabled, which can be used to align elements. It can be changed with:
``` yaml
plugins:
- social:
debug_grid_step: 64
```
[`debug_color`](#+social.debug_color){ #+social.debug_color }
: [:octicons-tag-24: insiders-4.33.0][Insiders] · :octicons-milestone-24:
Default: `grey` This option sets the color of the layer outlines and
the grid which are rendered when [`debug`][debug] is enabled. It can be
changed with:
``` yaml
plugins:
- social:
debug_color: yellow
```
[debug]: #+social.debug
#### Caching
The [built-in social plugin] implements an intelligent caching mechanism,
ensuring that social cards are only re-generated when they're not contained in
the cache or their contents change. If any of the variables used in a layout
changes, the plugin will detect it and re-generate the card.
The following configuration options are available for caching:
[`cache`](#+social.cache){ #+social.cache }
: [:octicons-tag-24: insiders-4.33.0][Insiders] · :octicons-milestone-24:
Default: `true` Whether the plugin queries its cache for an existing
artifact before starting a generation job. It's normally not necessary to
change this setting, except for when debugging the plugin itself. Caching
can be disabled with:
``` yaml
plugins:
- social:
cache: false
```
[`cache_dir`](#+social.cache_dir){ #+social.cache_dir }
: :octicons-milestone-24: Default: `.cache/plugins/social` This option
specifies the file system location of the plugin's cache. It's normally not
necessary to change this setting, except for when debugging the plugin
itself. The cache directory can be changed with:
``` yaml
plugins:
- social:
cache_dir: .cache/plugins/social
```
By default, all built-in plugins that implement caching will create a
`.cache` directory in the same folder your `mkdocs.yml` resides, and create
subfolders to not interfere with each other. If you use multiple instances
of this plugin, it could be necessary to change this setting.
[built-in social plugin]: #built-in-social-plugin
[publishing guide]: ../publishing-your-site.md#with-github-actions
## Usage
If you want to adjust the title or set a custom description for the social card,
you can set the front matter `title` and `description` properties, which take
precedence over the default values.
- [Changing the title]
- [Changing the description]
[Changing the title]: ../reference/index.md#setting-the-page-title
[Changing the description]: ../reference/index.md#setting-the-page-description
### Choosing a font
Some fonts do not contain CJK characters, like for example the
[default font, `Roboto`][font]. In case your `site_name`, `site_description`, or
page title contain CJK characters, choose another font from [Google Fonts] which
comes with CJK characters, e.g. one from the `Noto Sans` font family:
=== "Chinese (Simplified)"
``` yaml
plugins:
- social:
cards_font: Noto Sans SC
```
=== "Chinese (Traditional)"
``` yaml
plugins:
- social:
cards_font: Noto Sans TC
```
=== "Japanese"
``` yaml
plugins:
- social:
cards_font: Noto Sans JP
```
=== "Korean"
``` yaml
plugins:
- social:
cards_font: Noto Sans KR
```
## Customization
[:octicons-heart-fill-24:{ .mdx-heart } Sponsors only][Insiders]{ .mdx-insiders } ·
[:octicons-tag-24: insiders-4.33.0][Insiders] ·
:octicons-beaker-24: Experimental
[Insiders] ships a ground up rewrite of the [built-in social plugin] and
introduces a brand new layout system based on a combination of YAML and
[Jinja templates] the same engine Material for MkDocs uses for HTML
templating allowing for the creation of complex custom layouts:
<div class="mdx-social">
<div class="mdx-social__layer">
<div class="mdx-social__image">
<span class="mdx-social__label">Layer 0</span>
<img src="../../assets/screenshots/social-cards-layer-0.png" />
</div>
</div>
<div class="mdx-social__layer">
<div class="mdx-social__image">
<span class="mdx-social__label">Layer 1</span>
<img src="../../assets/screenshots/social-cards-layer-1.png" />
</div>
</div>
<div class="mdx-social__layer">
<div class="mdx-social__image">
<span class="mdx-social__label">Layer 2</span>
<img src="../../assets/screenshots/social-cards-layer-2.png" />
</div>
</div>
<div class="mdx-social__layer">
<div class="mdx-social__image">
<span class="mdx-social__label">Layer 3</span>
<img src="../../assets/screenshots/social-cards-layer-3.png" />
</div>
</div>
<div class="mdx-social__layer">
<div class="mdx-social__image">
<span class="mdx-social__label">Layer 4</span>
<img src="../../assets/screenshots/social-cards-layer-4.png" />
</div>
</div>
<div class="mdx-social__layer">
<div class="mdx-social__image">
<span class="mdx-social__label">Layer 5</span>
<img src="../../assets/screenshots/social-cards-layer-5.png" />
</div>
</div>
</div>
Social cards are composed of layers, analogous to how they are represented in
graphic design software such as Adobe Photoshop. As many layers are common
across the cards generated for each page (e.g., backgrounds or logos), the
built-in social plugin can automatically deduplicate layers and render them
just once, substantially accelerating card generation. The generated cards are
cached to ensure they are only regenerated when their contents change.
Layouts are written in YAML syntax. Before starting to create a custom layout,
it is a good idea to [study the pre-designed layouts] (link to [Insiders]
repository), in order to get a better understanding of how they work. Then,
create a new layout and reference it in `mkdocs.yml`:
=== ":octicons-file-code-16: `layouts/custom.yml`"
``` yaml
size: { width: 1200, height: 630 }
layers: []
```
=== ":octicons-file-code-16: `mkdocs.yml`"
``` yaml
plugins:
- social:
cards_layout_dir: layouts
cards_layout: custom
debug: true
```
Note that the `.yml` file extension should be omitted. Next, run `mkdocs serve`,
and see how the `.cache` directory is populated with the generated cards. Open
any card in your editor, so you can see your changes immediately. Since we
haven't defined any layers, the cards are transparent.
The following sections explain how to create custom layouts.
[Jinja templates]: https://jinja.palletsprojects.com/en/3.1.x/
[study the pre-designed layouts]: https://github.com/squidfunk/mkdocs-material-insiders/tree/master/src/plugins/social/layouts
### Size and offset
Each layer has an associated size and offset, which is defined in pixels. The
`size` is defined by a `width` and `height` property, and the `offset` by `x`
and `y` properties:
``` yaml
size: { width: 1200, height: 630 }
layers:
- size: { width: 1200, height: 630 }
offset: { x: 0, y: 0 }
```
If the `size` is omitted, it defaults to the size of the layout. If the `offset`
is omitted, it defaults to the top left corner, which is the origin for all
layers. Saving the layout and reloading renders:
![Layer size]
The layer outline and grid are visible because we enabled [`debug`][debug]
mode in `mkdocs.yml`. The top left shows the layer index and offset, which is
useful for alignment and composition.
[Layer size]: ../assets/screenshots/social-cards-layer-size.png
### Backgrounds
Each layer can be assigned a background color and image. If both are given, the
color is rendered on top of the image, allowing for semi-transparent, tinted
backgrounds:
=== "Background color"
``` yaml
size: { width: 1200, height: 630 }
layers:
- background:
color: "#4051b5"
```
![Layer background color]
=== "Background image"
``` yaml
size: { width: 1200, height: 630 }
layers:
- background:
image: layouts/background.jpg
```
![Layer background image]
=== "Background image, tinted"
``` yaml
size: { width: 1200, height: 630 }
layers:
- background:
image: layouts/background.jpg
color: "#4051b5ee" # (1)!
```
1. The color value can be set to a [CSS color keyword], or a 3, 4, 6 or 8
letter HEX color code, allowing for semi-transparent layers.
![Layer background]
Background images are automatically scaled to fit the layer while preserving
aspect-ratio. Notice how we omitted `size` and `offset`, because we want to
fill the entire area of the social card.
[Layer background color]: ../assets/screenshots/social-cards-layer-background-color.png
[Layer background image]: ../assets/screenshots/social-cards-layer-background-image.png
[Layer background]: ../assets/screenshots/social-cards-layer-background.png
### Typography
Now, we can add dynamic typography that is sourced from Markdown files - this is
the actual raison d'être of the [built-in social plugin]. [Jinja templates] are
used to render a text string that is then added to the image:
``` yaml
size: { width: 1200, height: 630 }
layers:
- size: { width: 832, height: 310 }
offset: { x: 62, y: 160 }
typography:
content: "{{ page.title }}" # (1)!
align: start
color: white
line:
amount: 3
height: 1.25
font:
family: Roboto
style: Bold
```
1. The following variables can be used in [Jinja templates]:
- [`config.*`][config variable]
- [`page.*`][page variable]
- [`layout.*`][layout options]
The author is free in defining `layout.*` options, which can be used to pass
arbitrary data to the layout from `mkdocs.yml`.
This renders a text layer with the title of the page with a line height of 1.25,
and a maximum number of 3 lines. The plugin automatically computes the font size
from the line height, the number of lines, and font metrics like ascender and
descender.[^2] This renders:
[^2]:
If the plugin would require the author to specify the font size and line
height manually, it would be impossible to guarantee that the text fits
into the layer. For this reason we implemented a declarative approach,
where the author specifies the desired line height and number of lines, and
the plugin computes the font size automatically.
![Layer typography]
[config variable]: https://www.mkdocs.org/dev-guide/themes/#config
[page variable]: https://www.mkdocs.org/dev-guide/themes/#page
[Layer typography]: ../assets/screenshots/social-cards-layer-typography.png
#### Overflow
If the text overflows the layer, it is automatically truncated and an ellipsis
is appended, e.g.:
``` { .markdown .no-copy }
# If we use a very long headline, we can see how the text will be truncated
```
![Layer typography ellipsis]
[Layer typography ellipsis]: ../assets/screenshots/social-cards-layer-typography-ellipsis.png
#### Alignment
Text can be aligned to all corners and edges of the layer. For example, if we
want to align the text to the middle of the layer, we can set `align` to `start center`, which will render as:
![Layer typography align]
[Layer typography align]: ../assets/screenshots/social-cards-layer-typography-align.png
The following table shows the supported values:
<figure markdown>
| Alignment | | |
| -------------- | --------------- | ------------ |
| :material-arrow-top-left: `start top` | :material-arrow-up: `center top` | :material-arrow-top-right: `end top` |
| :material-arrow-left: `start center` | :material-circle-small: `center` | :material-arrow-right: `end center` |
| :material-arrow-bottom-left: `start bottom` | :material-arrow-down: `center bottom` | :material-arrow-bottom-right: `end bottom` |
<figcaption>
Supported values for text alignment
</figcaption>
</figure>
#### Font
The [built-in social plugin] integrates with [Google Fonts] and will
automatically download the font files for you. The `font` property accepts a
`family` and `style` property, where the `family` must be set to the name of the
font, and the `style` to one of the supported font styles. For example, setting
`family` to `Roboto` will automatically download the following files:
``` { .sh .no-copy #example }
.cache/plugins/social/fonts
└─ Roboto/
├─ Black.ttf
├─ Black Italic.ttf
├─ Bold.ttf
├─ Bold Italic.ttf
├─ Italic.ttf
├─ Light.ttf
├─ Light Italic.ttf
├─ Medium.ttf
├─ Medium Italic.ttf
├─ Regular.ttf
├─ Thin.ttf
└─ Thin Italic.ttf
```
In that case, the author can use `Bold` or `Medium Italic` as the `style`. If
the font style specified in the layer is not part of the font family, the
font always falls back to `Regular` and prints a warning in [`debug`][debug]
mode, as `Regular` is included with all font families.
### Icons
Authors can leverage the full range of icons that are shipped with Material for
MkDocs, or even provide custom icons by using theme extension and going through
the process described in the guide on [additional icons]. Icons can even be
tinted by using the `color` property:
``` yaml
size: { width: 1200, height: 630 }
layers:
- background:
color: "#4051b5"
- size: { width: 144, height: 144 }
offset: { x: 992, y: 64 }
icon:
value: material/cat
color: white
```
This will render the icon in the top right corner of the social card:
![Layer icon]
The possibilities are endless. For example, icons can be used to draw shapes
like circles:
``` yaml
size: { width: 1200, height: 630 }
layers:
- background:
color: "#4051b5"
- size: { width: 2400, height: 2400 }
offset: { x: -1024, y: 64 }
icon:
value: material/circle
color: "#5c6bc0"
- size: { width: 1800, height: 1800 }
offset: { x: 512, y: -1024 }
icon:
value: material/circle
color: "#3949ab"
```
This will add two circles to the background:
![Layer icon circles]
__Are you missing something? Please [open a discussion] and let us know!__
[additional icons]: ./changing-the-logo-and-icons.md#additional-icons
[Layer icon]: ../assets/screenshots/social-cards-layer-icon.png
[Layer icon circles]: ../assets/screenshots/social-cards-layer-icon-circles.png
[open a discussion]: https://github.com/squidfunk/mkdocs-material/discussions/new