feat(api): add health-check endpoint

src/app.module.ts

@@ -10,6 +10,7 @@ import { MusicLibraryModule } from "./music-library/music-library.module";
 import { SourcesModule } from "./sources/sources.module";
 import { UsersModule } from "./users/users.module";
 import { ConfigModule } from "./config/config.module";
+import { HealthCheckModule } from "./health-check/health-check.module";
 
 @Module({
   imports: [
@@ -26,6 +27,7 @@ import { ConfigModule } from "./config/config.module";
     SourcesModule,
     MusicLibraryModule,
     ListensModule,
+    HealthCheckModule,
   ],
 })
 export class AppModule {}

src/health-check/health-check.controller.ts

@@ -0,0 +1,36 @@
+import { Controller, Get } from "@nestjs/common";
+import {
+  DNSHealthIndicator,
+  HealthCheck,
+  HealthCheckService,
+  TypeOrmHealthIndicator,
+} from "@nestjs/terminus";
+import { ConfigService } from "@nestjs/config";
+
+@Controller("api/v1/health")
+export class HealthCheckController {
+  constructor(
+    private readonly health: HealthCheckService,
+    private readonly dns: DNSHealthIndicator,
+    private readonly typeorm: TypeOrmHealthIndicator,
+    private readonly config: ConfigService
+  ) {}
+
+  @Get()
+  @HealthCheck()
+  check() {
+    return this.health.check([
+      () =>
+        this.dns.pingCheck(
+          "spotify-web",
+          this.config.get<string>("SPOTIFY_WEB_API_URL")
+        ),
+      () =>
+        this.dns.pingCheck(
+          "spotify-auth",
+          this.config.get<string>("SPOTIFY_AUTH_API_URL")
+        ),
+      () => this.typeorm.pingCheck("db"),
+    ]);
+  }
+}

src/health-check/health-check.module.ts

@@ -0,0 +1,6 @@
+import { Module } from "@nestjs/common";
+import { TerminusModule } from "@nestjs/terminus";
+import { HealthCheckController } from "./health-check.controller";
+
+@Module({ imports: [TerminusModule], controllers: [HealthCheckController] })
+export class HealthCheckModule {}