Allows to write stories in Svelte syntax
npm install @storybook/addon-svelte-csfThis Storybook addon allows you to write Storybook stories using the Svelte language instead of ESM that regular CSF is based on.
``bash`
npx storybook@latest add @storybook/addon-svelte-csf
Using the Svelte language makes it easier to write stories for composed components that rely on snippets or slots, which aren't easily re-created outside of Svelte files.
> [!TIP]
> If you've initialized your Storybook project with Storybook version 8.2.0 or above, this addon is already set up for you!
> [!IMPORTANT]
> Not running the latest and greatest versions of Storybook or Svelte? Be sure to check the version compatibility section below.
The easiest way to install the addon is with storybook add:
`bash`
npx storybook@latest add @storybook/addon-svelte-csf
You can also add the addon manually. First, install the package:
`bash`
npm install --save-dev @storybook/addon-svelte-csf
Then modify your main.ts Storybook configuration to include the addon and include *.stories.svelte files:
`diff`
export default {
- stories: ['../src//.mdx', '../src//.stories.@(js|jsx|mjs|ts|tsx)',
+ stories: ['../src//.mdx', '../src//.stories.@(js|jsx|mjs|ts|tsx|svelte)'],
addons: [
+ '@storybook/addon-svelte-csf',
...
],
...
}
Restart your Storybook server for the changes to take effect.
> [!NOTE]
> The documentation here does not cover all of Storybook's features, only the aspects that are specific to the addon and Svelte CSF. We recommend that you familiarize yourself with Storybook's core concepts at
The examples directory contains examples describing each feature of the addon. The Button.stories.svelte example is a good one to get started with. The Storybook with all the examples is published on Chromatic here.
Svelte CSF stories files must always have the .stories.svelte extension.
All stories files must have a "meta" (aka. "default export") defined, and its structure follows what's described in the official docs on the subject. To define the meta in Svelte CSF, call the defineMeta function within the module context, with the meta properties you want:
`svelte`
defineMeta returns an object with a Story component (see Defining stories below) that you must destructure out to use.
To define stories, you use the Story component returned from the defineMeta function. Depending on what you want the story to contain, there are multiple ways to use the Story component. Common for all the use case is that all properties of a regular CSF story are passed as props to the Story component, with the exception of the render function, which does not have any effect in Svelte CSF.
All story requires either the name prop or exportName prop.
> [!TIP]
> In versions prior to v5 of this addon, it was always required to define a template story with the component. This is no longer required and stories will default to render the component from meta if no template is set.
#### Plain Story
If your component only accepts props and doesn't require snippets or slots, you can use the simple form of defining stories, only using args:
`svelte`
This will render the component defined in the meta, with the args passed as props.
#### With children
If your component needs children, you can pass them in directly to the story, and they will be forwarded to your component:
`svelte`
#### Static template
If you need more customization of the story, like composing components or defining snippets, you can set the asChild prop on the Story. Instead of forwarding the children to your component, it will instead use the children directly as the story output. This allows you to write whatever component structure you desire:
`svelte`
> [!IMPORTANT]
> This format completely ignores args, as they are not passed down to any of the child components defined. Even if your story has args and Controls, they won't have an effect. See the snippet-based formats below.
#### Inline snippet
If you need composition/snippets but also want a dynamic story that reacts to args or the story context, you can define a template snippet in the Story component:
`svelte`
{#snippet template(args)}
{/snippet}
#### Shared snippet
Often your stories are very similar and their only differences are args or play-functions. In this case it can be cumbersome to define the same template snippet over and over again. You can share snippets by defining them at the top-level and passing them as props to Story:
`svelte
{#snippet template(args)}
{#if args.simpleChild}
{:else}
{/if}
{/snippet}
`
You can also use this pattern to define multiple templates and share the different templates among different stories.
#### Default snippet
If you only need a single template that you want to share, it can be tedious to include {template} in each Story component. Like in th example below:
`svelte`
Similar to regular CSF, you can define a meta-level render-function, by referencing your default snippet in the render property of your defineMeta call:
`svelte
{#snippet template(args)}
{#if args.simpleChild}
{:else}
{/if}
{/snippet}
`
Stories can still override this default snippet using any of the methods for defining story-level content.
> [!NOTE]
> Svelte has the limitation, that you can't reference a snippet from a
{#snippet template(args: Args, context: StoryContext
{/snippet}
`
If you use the render-property to define a custom template that might use custom args, the args will be inferred from the types of the snippet passed to render. This is especially useful when you're converting primitive args to snippets:
`svelte
{#snippet template({ children, ...args }: Args, context: StoryContext
{children}
{#snippet footer()}
{args.footer}
{/snippet}
{/snippet}
`
See the Types.stories.svelte examples on how to use complex types properly.
Version 5 of the addon changes the API from v4 in key areas, as described above. However a feature flag has been introduced to maintain support for the -based legacy API as it was prior to v5.
To enable supoprt for the legacy API, make the following change to your main Storybook config:
`diff`
export default {
addons: [
- '@storybook/addon-svelte-csf',
+ {
+ name: '@storybook/addon-svelte-csf',
+ options: {
+ legacyTemplate: true
+ },
...
],
...
}
This can make the overall experience slower, because it adds more transformation steps on top of the existing ones. It should only be used temporarily while migrating to the new API. It's highly likely that the legacy support will be dropped in future major versions of the addon.
The legacy support is not bullet-proof, and it might not work in all scenarios that previously worked. If you're experiencing issues or getting errors after upgrading to v5, try migrating the problematic stories files to the modern API.
Version 5 and up of this addon requires _at least_:
| Dependency | Version |
| ---------------------------------------------------------------------------------------------------------------------- | -------- |
| Storybook | v8.0.0 |v5.0.0
| Svelte | |v5.0.0
| Vite | |@sveltejs/vite-plugin-svelte
| | v4.0.0 |
> [!IMPORTANT]
> As of v5 this addon does not support Webpack.
`bash`
npm install --save-dev @storybook/addon-svelte-csf@^4
Version 4 of this addon requires _at least_:
- Storybook v7
- Svelte v4
- Vite v4 (if using Vite)
- @sveltejs/vite-plugin-svelte v2 (if using Vite)
`bash`
npm install --save-dev @storybook/addon-svelte-csf@^3
Version 3 of this addon requires _at least_:
- Storybook v7
- Svelte v3
`bash`
npm install --save-dev @storybook/addon-svelte-csf@^2
If you're using Storybook between v6.4.20 and v7.0.0, you should use version ^2.0.0 of this addon.
This project uses pnpm for dependency management.
1. Install dependencies with pnpm install
2. Concurrently start the compilation and the internal Storybook with
3. Restarting the internal Storybook is often needed for changes to take effect.