svelte/documentation/docs/04-compiler-and-api/03-server-side-component-api.md

title
Server-side component API

// @noErrors
const result = Component.render(...)

Unlike client-side components, server-side components don't have a lifespan after you render them — their whole job is to create some HTML and CSS. For that reason, the API is somewhat different.

A server-side component exposes a render method that can be called with optional props. It returns an object with head, html, and css properties, where head contains the contents of any <svelte:head> elements encountered.

You can import a Svelte component directly into Node using svelte/register.

// @noErrors
require('svelte/register');

const App = require('./App.svelte').default;

const { head, html, css } = App.render({
	answer: 42
});

The .render() method accepts the following parameters:

parameter	default	description
props	{}	An object of properties to supply to the component
options	{}	An object of options

The options object takes in the following options:

option	default	description
context	new Map()	A Map of root-level context key-value pairs to supply to the component

// @noErrors
const { head, html, css } = App.render(
	// props
	{ answer: 42 },
	// options
	{
		context: new Map([['context-key', 'context-value']])
	}
);