working test deploy config

src/app/services/app-config.service.ts

@@ -0,0 +1,42 @@
+import { HttpClient } from '@angular/common/http';
+import { APP_INITIALIZER, InjectionToken } from '@angular/core';
+import { lastValueFrom } from 'rxjs';
+
+export interface AppConfig {
+  apiBaseUrl: string;
+}
+
+export const APP_CONFIG = new InjectionToken<AppConfig>('appConfig');
+
+const _appConfig: AppConfig = {
+  apiBaseUrl: '',
+};
+
+export function appConfigFactory(http: HttpClient) {
+  return (): Promise<void> => {
+    return lastValueFrom(http.get<AppConfig>('./config.json')).then(
+      (config) => {
+        Object.assign(_appConfig, config);
+      },
+      () => {
+        // Keep defaults if config.json is not available (dev mode).
+      },
+    );
+  };
+}
+
+export const appConfigProvider = {
+  provide: APP_CONFIG,
+  useValue: _appConfig,
+};
+
+export const appConfigInitProvider = {
+  provide: APP_INITIALIZER,
+  useFactory: appConfigFactory,
+  deps: [HttpClient],
+  multi: true,
+};
+
+export function getAppConfig(): AppConfig {
+  return _appConfig;
+}