If an adapter for your preferred environment doesn't yet exist, you can build your own. We recommend looking at the source for an adapter to a platform similar to yours and copying it as a starting point.
Adapters packages must implement the following API, which creates an Adapter
:
// @filename: ambient.d.ts
type AdapterSpecificOptions = any;
// @filename: index.js
// ---cut---
/** @param {AdapterSpecificOptions} options */
export default function (options) {
/** @type {import('@sveltejs/kit').Adapter} */
const adapter = {
name: 'adapter-package-name',
async adapt(builder) {
// adapter implementation
}
};
return adapter;
}
The types for Adapter
and its parameters are available in types/index.d.ts.
Within the adapt
method, there are a number of things that an adapter should do:
- Clear out the build directory
- Write SvelteKit output with
builder.writeClient
,builder.writeServer
, andbuilder.writePrerendered
- Output code that:
- Imports
Server
from${builder.getServerDirectory()}/index.js
- Instantiates the app with a manifest generated with
builder.generateManifest({ relativePath })
- Listens for requests from the platform, converts them to a standard Request if necessary, calls the
server.respond(request, { getClientAddress })
function to generate a Response and responds with it - expose any platform-specific information to SvelteKit via the
platform
option passed toserver.respond
- Globally shims
fetch
to work on the target platform, if necessary. SvelteKit provides a@sveltejs/kit/install-fetch
helper for platforms that can usenode-fetch
- Imports
- Bundle the output to avoid needing to install dependencies on the target platform, if necessary
- Put the user's static files and the generated JS/CSS in the correct location for the target platform
Where possible, we recommend putting the adapter output under the build/
directory with any intermediate output placed under .svelte-kit/[adapter-name]
.