using-vue.md

Using Vue in Markdown

Browser API Access Restrictions

Because VuePress applications are server-rendered in Node.js when generating static builds, any Vue usage must conform to the universal code requirements. In short, make sure to only access Browser / DOM APIs in beforeMounted or mounted hooks.

If you are using or demoing components that are not SSR friendly (for example containing custom directives), you can wrap them inside the built-in <ClientOnly> component:

<ClientOnly>
  <NonSSRFriendlyComponent/>
</ClientOnly>

Note this does not fix components or libraries that access Browser APIs on import - in order to use code that assumes a browser environment on import, you need to dynamically import them in proper lifecycle hooks:

<script>
export default {
  mounted () {
    import('./lib-that-access-window-on-import').then(module => {
      // use code
    })
  }
}
</script>

Templating

Interpolation

Each markdown file is first compiled into HTML and then passed on as a Vue component to vue-loader. This means you can use Vue-style interpolation in text:

Input

{{ 1 + 1 }}

Output

{{ 1 + 1 }}

Directives

Directives also work:

Input

<span v-for="i in 3">{{ i }} </span>

Output

{{ i }} 

Access to Site & Page Data

The compiled component does not have any private data but does have access to the site metadata. For example:

Input

{{ $page }}

Output

{
  "path": "/using-vue.html",
  "title": "Using Vue in Markdown",
  "frontmatter": {}
}

Escaping

By default, fenced code blocks are automatically wrapped with v-pre. If you want to display raw mustaches or Vue-specific syntax inside inline code snippets or plain text, you need to wrap a paragraph with the v-pre custom container:

Input

::: v-pre
`{{ This will be displayed as-is }}`
:::

Output

::: v-pre {{ This will be displayed as-is }} :::

Using Components

Any *.vue files found in .vuepress/components are automatically registered as global, async components. For example:

.
└─ .vuepress
   └─ components
      ├─ demo-1.vue
      ├─ OtherComponent.vue
      └─ Foo
         └─ Bar.vue

Inside any markdown file you can then directly use the components (names are inferred from filenames):

<demo-1/>
<OtherComponent/>
<Foo-Bar/>

::: warning IMPORTANT Make sure a custom component's name either contains a hyphen or is in PascalCase. Otherwise it will be treated as an inline element and wrapped inside a <p> tag, which will lead to hydration mismatch because <p> does not allow block elements to be placed inside it. :::

Using Pre-processors

VuePress has built-in webpack config for the following pre-processors: sass, scss, less, stylus and pug. All you need to do is installing the corresponding dependencies. For example, to enable sass, install the following in your project:

yarn add -D sass-loader node-sass

Now you can use the following in markdown and theme components:

<style lang="sass">
.title
  font-size: 20px
</style>

Using <template lang="pug"> requires installing pug and pug-plain-loader:

yarn add -D pug pug-plain-loader

::: tip If you are a Stylus user, you don't need to install stylus and stylus-loader in your project because VuePress uses Stylus internally.

For pre-processors that do not have built-in webpack config support, you will need to extend the internal webpack config in addition to installing the necessary dependencies. :::

Script & Style Hoisting

Sometimes you may need to apply some JavaScript or CSS only to the current page. In those cases you can directly write root-level <script> or <style> blocks in the markdown file, and they will be hoisted out of the compiled HTML and used as the <script> and <style> blocks for the resulting Vue single-file component.

<style module> .example { color: #41b883; } </style> <script> export default { mounted () { document.querySelector(`.${this.$style.example}`) .textContent = 'This is rendered by inline script and styled by inline CSS' } } </script>