# handle

**Kind:** Function

**Source:** [`src/adapter/service-worker/handler.ts`](https://github.com/honojs/hono/blob/main/src/adapter/service-worker/handler.ts#L18)

**Part of:** [Adapter](subsystem-src-adapter)

Adapter for Service Worker

`handle` adapts Service Worker fetch events to the application's request handler. It receives an incoming request, runs it through the adapter flow, and returns the response used by the Service Worker.

## Signature

```ts
function handle(app: Hono<E, S, BasePath>, opts: HandleOptions): Handler
```

## Parameters

| Name | Type |
|---|---|
| `app` | `Hono<E, S, BasePath>` |
| `opts` | `HandleOptions` |

**Returns:** `Handler`

## Diagram

```mermaid
graph LR
  FetchEvent[Service Worker fetch event] --> Request[Request]
  Request --> Handle[handle]
  Handle --> App[Application handler]
  App --> Response[Response]
  Response --> FetchEvent
```

## Usage

```ts
import { handle } from './handler'

self.addEventListener('fetch', (event) => {
  event.respondWith(handle(event.request))
})
```

## AI Coding Instructions

- Keep the Service Worker adapter focused on converting incoming requests into application handler calls.
- Return the handler response directly so `fetch` events receive a valid `Response`.
- Register `handle` through `event.respondWith(...)` when wiring Service Worker fetch events.
- Do not add browser window APIs to this module; Service Worker code runs in a worker context.