ssr.md

Server-Side Rendering API {#server-side-rendering-api}

renderToString() {#rendertostring}

• Exported from vue/server-renderer

• Type

  function renderToString(
    input: App | VNode,
    context?: SSRContext
  ): Promise<string>

• Example

  import { createSSRApp } from 'vue'
  import { renderToString } from 'vue/server-renderer'
  
  const app = createSSRApp({
    data: () => ({ msg: 'hello' }),
    template: `<div>{{ msg }}</div>`
  })
  
  ;(async () => {
    const html = await renderToString(app)
    console.log(html)
  })()

  SSR Context {#ssr-context}

  You can pass an optional context object, which can be used to record additional data during the render, for example accessing content of Teleports:

  const ctx = {}
  const html = await renderToString(app, ctx)
  
  console.log(ctx.teleports) // { '#teleported': 'teleported content' }

  Most other SSR APIs on this page also optionally accept a context object. The context object can be accessed in component code via the useSSRContext helper.

• See also Guide - Server-Side Rendering

renderToNodeStream() {#rendertonodestream}

Renders input as a Node.js Readable stream.

• Exported from vue/server-renderer

• Type

  function renderToNodeStream(
    input: App | VNode,
    context?: SSRContext
  ): Readable

• Example

  // inside a Node.js http handler
  renderToNodeStream(app).pipe(res)

  :::tip Note This method is not supported in the ESM build of vue/server-renderer, which is decoupled from Node.js environments. Use pipeToNodeWritable instead. :::

pipeToNodeWritable() {#pipetonodewritable}

Render and pipe to an existing Node.js Writable stream instance.

• Exported from vue/server-renderer

• Type

  function pipeToNodeWritable(
    input: App | VNode,
    context: SSRContext = {},
    writable: Writable
  ): void

• Example

  // inside a Node.js http handler
  pipeToNodeWritable(app, {}, res)

renderToWebStream() {#rendertowebstream}

Renders input as a Web ReadableStream.

• Exported from vue/server-renderer

• Type

  function renderToWebStream(
    input: App | VNode,
    context?: SSRContext
  ): ReadableStream

• Example

  // inside an environment with ReadableStream support
  return new Response(renderToWebStream(app))

  :::tip Note In environments that do not expose ReadableStream constructor in the global scope, pipeToWebWritable() should be used instead. :::

pipeToWebWritable() {#pipetowebwritable}

Render and pipe to an existing Web WritableStream instance.

• Exported from vue/server-renderer

• Type

  function pipeToWebWritable(
    input: App | VNode,
    context: SSRContext = {},
    writable: WritableStream
  ): void

• Example

  This is typically used in combination with TransformStream:

  // TransformStream is available in environments such as CloudFlare workers.
  // in Node.js, TransformStream needs to be explicitly imported from 'stream/web'
  const { readable, writable } = new TransformStream()
  pipeToWebWritable(app, {}, writable)
  
  return new Response(readable)

renderToSimpleStream() {#rendertosimplestream}

Renders input in streaming mode using a simple readable interface.

• Exported from vue/server-renderer

• Type

  function renderToSimpleStream(
    input: App | VNode,
    context: SSRContext,
    options: SimpleReadable
  ): SimpleReadable
  
  interface SimpleReadable {
    push(content: string | null): void
    destroy(err: any): void
  }

• Example

  let res = ''
  
  renderToSimpleStream(
    app,
    {},
    {
      push(chunk) {
        if (chunk === null) {
          // done
          console(`render complete: ${res}`)
        } else {
          res += chunk
        }
      },
      destroy(err) {
        // error encountered
      }
    }
  )

useSSRContext() {#usessrcontext}

A runtime API used to retrieve the context object passed to renderToString() or other server render APIs.

• Type

  function useSSRContext<T = Record<string, any>>(): T | undefined

• Example

  The retrieved context can be used to attach information that is needed for rendering the final HTML (e.g. head metadata).

  <script setup>
  import { useSSRContext } from 'vue'
  
  // make sure to only call it during SSR
  // https://vitejs.dev/guide/ssr.html#conditional-logic
  if (import.meta.env.SSR) {
    const ctx = useSSRContext()
    // ...attach properties to the context
  }
  </script>