Make realtime base compatible with Angular DI

projects/kit/src/lib/realtime/kit-realtime-connection.spec.ts

@@ -1,4 +1,6 @@
 import type { PluginListenerHandle } from '@capacitor/core';
+import { Injectable } from '@angular/core';
+import { TestBed } from '@angular/core/testing';
 import { afterEach, describe, expect, it, vi } from 'vitest';
 import { kitRealtimeProtocols, KitRealtimeConnection, KitRealtimeLivenessWatchdog, toKitWebSocketUrl } from './kit-realtime-connection';
 
@@ -41,8 +43,8 @@ class TestConnection extends KitRealtimeConnection<TestEvent> {
   readonly removeNetworkListener = vi.fn(() => Promise.resolve());
   appListenerResolver: ((handle: PluginListenerHandle) => void) | null = null;
 
-  constructor() {
-    super({ clientId: 'self', openTimeoutMs: 15_000, pingIntervalMs: 30_000, livenessTimeoutMs: 70_000 });
+  protected override get realtimeOptions(): { clientId: string } {
+    return { clientId: 'self' };
   }
 
   protected get shouldConnect(): boolean {
@@ -103,6 +105,15 @@ class TestConnection extends KitRealtimeConnection<TestEvent> {
   }
 }
 
+@Injectable()
+class InheritedConstructorConnection extends KitRealtimeConnection<TestEvent> {
+  protected readonly shouldConnect = false;
+
+  protected buildSocketTargets(): Promise<{ url: string; protocols: string[] }[]> {
+    return Promise.resolve([]);
+  }
+}
+
 describe('KitRealtimeConnection', () => {
   afterEach(() => vi.useRealTimers());
 
@@ -112,6 +123,11 @@ describe('KitRealtimeConnection', () => {
     expect(kitRealtimeProtocols('app-v1', { authToken: 'token', clientId: 'client' })).toEqual(['app-v1', 'auth.token', 'client.client']);
   });
 
+  it('can be inherited by an Angular injectable without declaring a constructor', () => {
+    TestBed.configureTestingModule({ providers: [InheritedConstructorConnection] });
+    expect(TestBed.inject(InheritedConstructorConnection)).toBeInstanceOf(InheritedConstructorConnection);
+  });
+
   it('pings all targets and atomically reconnects after one closes', async () => {
     vi.useFakeTimers();
     const connection = new TestConnection();

projects/kit/src/lib/realtime/kit-realtime-connection.ts

@@ -1,6 +1,7 @@
 import { App } from '@capacitor/app';
 import type { PluginListenerHandle } from '@capacitor/core';
 import { Network } from '@capacitor/network';
+import { Injectable } from '@angular/core';
 import type { Observable } from 'rxjs';
 import { Subject } from 'rxjs';
 
@@ -97,13 +98,12 @@ export class KitRealtimeLivenessWatchdog {
  * suspension, exponential backoff, open/liveness timeouts, runtime-friendly application pings,
  * all-target atomic reconnect, and a resync signal after connectivity is restored.
  */
+@Injectable()
 export abstract class KitRealtimeConnection<TEvent extends KitRealtimeEvent> {
   readonly #events$ = new Subject<KitClientRealtimeEvent<TEvent>>();
   readonly #reconnected$ = new Subject<void>();
-  readonly #options: Required<KitRealtimeConnectionOptions>;
 
   /** Client ID used to classify self echoes. */
-  readonly id: string;
   protected readonly listeners: PluginListenerHandle[] = [];
 
   #sockets = new Set<WebSocket>();
@@ -125,8 +125,14 @@ export abstract class KitRealtimeConnection<TEvent extends KitRealtimeEvent> {
   /** Emits once after every fully restored connection cycle, prompting consumers to resync via REST. */
   readonly reconnected$: Observable<void> = this.#reconnected$.asObservable();
 
-  protected constructor(options: KitRealtimeConnectionOptions = {}) {
-    this.#options = {
+  /** Override timing/protocol defaults in specialized clients or tests. */
+  protected get realtimeOptions(): KitRealtimeConnectionOptions {
+    return {};
+  }
+
+  get #options(): Required<KitRealtimeConnectionOptions> {
+    const options = this.realtimeOptions;
+    return {
       clientId: options.clientId ?? KIT_REALTIME_CLIENT_ID,
       ping: options.ping ?? 'ping',
       pong: options.pong ?? 'pong',
@@ -135,7 +141,11 @@ export abstract class KitRealtimeConnection<TEvent extends KitRealtimeEvent> {
       pingIntervalMs: options.pingIntervalMs ?? 30_000,
       livenessTimeoutMs: options.livenessTimeoutMs ?? 70_000,
     };
-    this.id = this.#options.clientId;
+  }
+
+  /** Client ID used to classify self echoes. */
+  get id(): string {
+    return this.#options.clientId;
   }
 
   /** Whether every configured socket is currently open. */