feat: ServiceWorkerMain (#45232)

* feat: ServiceWorkerMain

* refactor: disconnect remote

* handle version_info_ nullptr case

* initiate finish request when possible and enumerate errors

* explicit name for test method

* oops

* fix: wait for redundant version to stop before destroying

* docs: clarify when undefined is returned

* chore: remove extra semicolons

docs/README.md

@@ -127,6 +127,7 @@ These individual tutorials expand on topics discussed in the guide above.
 * [pushNotifications](api/push-notifications.md)
 * [safeStorage](api/safe-storage.md)
 * [screen](api/screen.md)
+* [ServiceWorkerMain](api/service-worker-main.md)
 * [session](api/session.md)
 * [ShareMenu](api/share-menu.md)
 * [systemPreferences](api/system-preferences.md)

docs/api/service-worker-main.md

@@ -0,0 +1,34 @@
+# ServiceWorkerMain
+
+> An instance of a Service Worker representing a version of a script for a given scope.
+
+Process: [Main](../glossary.md#main-process)
+
+## Class: ServiceWorkerMain
+
+Process: [Main](../glossary.md#main-process)<br />
+_This class is not exported from the `'electron'` module. It is only available as a return value of other methods in the Electron API._
+
+### Instance Methods
+
+#### `serviceWorker.isDestroyed()` _Experimental_
+
+Returns `boolean` - Whether the service worker has been destroyed.
+
+#### `serviceWorker.startTask()` _Experimental_
+
+Returns `Object`:
+
+- `end` Function - Method to call when the task has ended. If never called, the service won't terminate while otherwise idle.
+
+Initiate a task to keep the service worker alive until ended.
+
+### Instance Properties
+
+#### `serviceWorker.scope` _Readonly_ _Experimental_
+
+A `string` representing the scope URL of the service worker.
+
+#### `serviceWorker.versionId` _Readonly_ _Experimental_
+
+A `number` representing the ID of the specific version of the service worker script in its scope.

docs/api/service-workers.md

@@ -56,6 +56,17 @@ Returns:
 
 Emitted when a service worker has been registered. Can occur after a call to [`navigator.serviceWorker.register('/sw.js')`](https://developer.mozilla.org/en-US/docs/Web/API/ServiceWorkerContainer/register) successfully resolves or when a Chrome extension is loaded.
 
+#### Event: 'running-status-changed' _Experimental_
+
+Returns:
+
+* `details` Event\<\>
+  * `versionId` number - ID of the updated service worker version
+  * `runningStatus` string - Running status.
+    Possible values include `starting`, `running`, `stopping`, or `stopped`.
+
+Emitted when a service worker's running status has changed.
+
 ### Instance Methods
 
 The following methods are available on instances of `ServiceWorkers`:
@@ -64,10 +75,56 @@ The following methods are available on instances of `ServiceWorkers`:
 
 Returns `Record<number, ServiceWorkerInfo>` - A [ServiceWorkerInfo](structures/service-worker-info.md) object where the keys are the service worker version ID and the values are the information about that service worker.
 
-#### `serviceWorkers.getFromVersionID(versionId)`
+#### `serviceWorkers.getInfoFromVersionID(versionId)`
 
-* `versionId` number
+* `versionId` number - ID of the service worker version
 
 Returns [`ServiceWorkerInfo`](structures/service-worker-info.md) - Information about this service worker
 
 If the service worker does not exist or is not running this method will throw an exception.
+
+#### `serviceWorkers.getFromVersionID(versionId)` _Deprecated_
+
+* `versionId` number - ID of the service worker version
+
+Returns [`ServiceWorkerInfo`](structures/service-worker-info.md) - Information about this service worker
+
+If the service worker does not exist or is not running this method will throw an exception.
+
+**Deprecated:** Use the new `serviceWorkers.getInfoFromVersionID` API.
+
+#### `serviceWorkers.getWorkerFromVersionID(versionId)` _Experimental_
+
+* `versionId` number - ID of the service worker version
+
+Returns [`ServiceWorkerMain | undefined`](service-worker-main.md) - Instance of the service worker associated with the given version ID. If there's no associated version, or its running status has changed to 'stopped', this will return `undefined`.
+
+#### `serviceWorkers.startWorkerForScope(scope)` _Experimental_
+
+* `scope` string - The scope of the service worker to start.
+
+Returns `Promise<ServiceWorkerMain>` - Resolves with the service worker when it's started.
+
+Starts the service worker or does nothing if already running.
+
+<!-- TODO(samuelmaddock): extend example to send IPC after starting worker -->
+
+```js
+const { app, session } = require('electron')
+const { serviceWorkers } = session.defaultSession
+
+// Collect service workers scopes
+const workerScopes = Object.values(serviceWorkers.getAllRunning()).map((info) => info.scope)
+
+app.on('browser-window-created', async (event, window) => {
+  for (const scope of workerScopes) {
+    try {
+      // Ensure worker is started
+      await serviceWorkers.startWorkerForScope(scope)
+    } catch (error) {
+      console.error(`Failed to start service worker for ${scope}`)
+      console.error(error)
+    }
+  }
+})
+```

docs/api/structures/service-worker-info.md

@@ -3,3 +3,4 @@
 * `scriptUrl` string - The full URL to the script that this service worker runs
 * `scope` string - The base URL that this service worker is active for.
 * `renderProcessId` number - The virtual ID of the process that this service worker is running in.  This is not an OS level PID.  This aligns with the ID set used for `webContents.getProcessId()`.
+* `versionId` number - ID of the service worker version

docs/breaking-changes.md

@@ -14,6 +14,21 @@ This document uses the following convention to categorize breaking changes:
 
 ## Planned Breaking API Changes (35.0)
 
+### Deprecated: `getFromVersionID` on `session.serviceWorkers`
+
+The `session.serviceWorkers.fromVersionID(versionId)` API has been deprecated
+in favor of `session.serviceWorkers.getInfoFromVersionID(versionId)`. This was
+changed to make it more clear which object is returned with the introduction
+of the `session.serviceWorkers.getWorkerFromVersionID(versionId)` API.
+
+```js
+// Deprecated
+session.serviceWorkers.fromVersionID(versionId)
+
+// Replace with
+session.serviceWorkers.getInfoFromVersionID(versionId)
+```
+
 ### Deprecated: `setPreloads`, `getPreloads` on `Session`
 
 `registerPreloadScript`, `unregisterPreloadScript`, and `getPreloadScripts` are introduced as a
@@ -21,7 +36,7 @@ replacement for the deprecated methods. These new APIs allow third-party librari
 preload scripts without replacing existing scripts. Also, the new `type` option allows for
 additional preload targets beyond `frame`.
 
-```ts
+```js
 // Deprecated
 session.setPreloads([path.join(__dirname, 'preload.js')])
 
@@ -75,15 +90,15 @@ immediately upon being received. Otherwise, it's not guaranteed to point to the
 same webpage as when received. To avoid misaligned expectations, Electron will
 return `null` in the case of late access where the webpage has changed.
 
-```ts
+```js
 ipcMain.on('unload-event', (event) => {
-  event.senderFrame; // ✅ accessed immediately
-});
+  event.senderFrame // ✅ accessed immediately
+})
 
 ipcMain.on('unload-event', async (event) => {
-  await crossOriginNavigationPromise;
-  event.senderFrame; // ❌ returns `null` due to late access
-});
+  await crossOriginNavigationPromise
+  event.senderFrame // ❌ returns `null` due to late access
+})
 ```
 
 ### Behavior Changed: custom protocol URL handling on Windows