feat(observability): Replace Prometheus package with OpenTelemetry

src/sources/scheduler.service.ts

@@ -1,20 +1,18 @@
-import { Injectable, OnApplicationBootstrap } from "@nestjs/common";
+import { Injectable, Logger, OnApplicationBootstrap } from "@nestjs/common";
 import { ConfigService } from "@nestjs/config";
 import { SchedulerRegistry } from "@nestjs/schedule";
 import { captureException } from "@sentry/node";
-import { Logger } from "../logger/logger.service";
 import { SpotifyService } from "./spotify/spotify.service";
 
 @Injectable()
 export class SchedulerService implements OnApplicationBootstrap {
+  private readonly logger = new Logger(this.constructor.name);
+
   constructor(
     private readonly config: ConfigService,
     private readonly registry: SchedulerRegistry,
-    private readonly spotifyService: SpotifyService,
-    private readonly logger: Logger
-  ) {
-    this.logger.setContext(this.constructor.name);
-  }
+    private readonly spotifyService: SpotifyService
+  ) {}
 
   onApplicationBootstrap() {
     this.setupSpotifyCrawler();

src/sources/spotify/spotify.service.spec.ts

@@ -1,6 +1,5 @@
 import { Test, TestingModule } from "@nestjs/testing";
 import { ListensService } from "../../listens/listens.service";
-import { Logger } from "../../logger/logger.service";
 import { MusicLibraryService } from "../../music-library/music-library.service";
 import { UsersService } from "../../users/users.service";
 import { SpotifyApiService } from "./spotify-api/spotify-api.service";
@@ -14,7 +13,6 @@ describe("SpotifyService", () => {
   let musicLibraryService: MusicLibraryService;
   let spotifyApi: SpotifyApiService;
   let spotifyAuth: SpotifyAuthService;
-  let logger: Logger;
 
   beforeEach(async () => {
     const module: TestingModule = await Test.createTestingModule({
@@ -25,7 +23,6 @@ describe("SpotifyService", () => {
         { provide: MusicLibraryService, useFactory: () => ({}) },
         { provide: SpotifyApiService, useFactory: () => ({}) },
         { provide: SpotifyAuthService, useFactory: () => ({}) },
-        { provide: Logger, useValue: new Logger() },
       ],
     }).compile();
 
@@ -35,7 +32,6 @@ describe("SpotifyService", () => {
     musicLibraryService = module.get<MusicLibraryService>(MusicLibraryService);
     spotifyApi = module.get<SpotifyApiService>(SpotifyApiService);
     spotifyAuth = module.get<SpotifyAuthService>(SpotifyAuthService);
-    logger = module.get<Logger>(Logger);
   });
 
   it("should be defined", () => {
@@ -45,6 +41,5 @@ describe("SpotifyService", () => {
     expect(musicLibraryService).toBeDefined();
     expect(spotifyApi).toBeDefined();
     expect(spotifyAuth).toBeDefined();
-    expect(logger).toBeDefined();
   });
 });

src/sources/spotify/spotify.service.ts

@@ -1,6 +1,6 @@
-import { Injectable } from "@nestjs/common";
+import { Injectable, Logger } from "@nestjs/common";
+import { Span } from "nestjs-otel";
 import { ListensService } from "../../listens/listens.service";
-import { Logger } from "../../logger/logger.service";
 import { Album } from "../../music-library/album.entity";
 import { Artist } from "../../music-library/artist.entity";
 import { Genre } from "../../music-library/genre.entity";
@@ -17,6 +17,8 @@ import { SpotifyAuthService } from "./spotify-auth/spotify-auth.service";
 
 @Injectable()
 export class SpotifyService {
+  private readonly logger = new Logger(this.constructor.name);
+
   private appAccessToken: string | null;
   private appAccessTokenInProgress: Promise<void> | null;
 
@@ -25,12 +27,10 @@ export class SpotifyService {
     private readonly listensService: ListensService,
     private readonly musicLibraryService: MusicLibraryService,
     private readonly spotifyApi: SpotifyApiService,
-    private readonly spotifyAuth: SpotifyAuthService,
-    private readonly logger: Logger
-  ) {
-    this.logger.setContext(this.constructor.name);
-  }
+    private readonly spotifyAuth: SpotifyAuthService
+  ) {}
 
+  @Span()
   async runCrawlerForAllUsers(): Promise<void> {
     this.logger.debug("Starting Spotify crawler loop");
     const users = await this.usersService.findAll();
@@ -42,11 +42,12 @@ export class SpotifyService {
     }
   }
 
+  @Span()
   async crawlListensForUser(
     user: User,
     retryOnExpiredToken: boolean = true
   ): Promise<void> {
-    this.logger.debug(`Crawling recently played tracks for user "${user.id}"`);
+    this.logger.debug({ userId: user.id }, `Crawling recently played tracks`);
 
     let playHistory: PlayHistoryObject[];
     try {
@@ -64,6 +65,7 @@ export class SpotifyService {
           await this.crawlListensForUser(user, false);
         } catch (errFromAuth) {
           this.logger.error(
+            { userId: user.id },
             `Refreshing access token failed for user "${user.id}": ${errFromAuth}`
           );
         }
@@ -95,6 +97,7 @@ export class SpotifyService {
 
         if (!isDuplicate) {
           this.logger.debug(
+            { userId: user.id },
             `New listen found! ${user.id} listened to "${
               track.name
             }" by ${track.artists
@@ -126,6 +129,7 @@ export class SpotifyService {
     });
   }
 
+  @Span()
   async runUpdaterForAllEntities(): Promise<void> {
     this.logger.debug("Starting Spotify updater loop");
 
@@ -137,6 +141,7 @@ export class SpotifyService {
     }
   }
 
+  @Span()
   async importTrack(
     spotifyID: string,
     retryOnExpiredToken: boolean = true
@@ -187,6 +192,7 @@ export class SpotifyService {
     });
   }
 
+  @Span()
   async importAlbum(
     spotifyID: string,
     retryOnExpiredToken: boolean = true
@@ -233,6 +239,7 @@ export class SpotifyService {
     });
   }
 
+  @Span()
   async importArtist(
     spotifyID: string,
     retryOnExpiredToken: boolean = true
@@ -277,6 +284,7 @@ export class SpotifyService {
     });
   }
 
+  @Span()
   async updateArtist(
     spotifyID: string,
     retryOnExpiredToken: boolean = true
@@ -315,6 +323,7 @@ export class SpotifyService {
     return artist;
   }
 
+  @Span()
   async importGenre(name: string): Promise<Genre> {
     const genre = await this.musicLibraryService.findGenre({
       name,
@@ -328,6 +337,7 @@ export class SpotifyService {
     });
   }
 
+  @Span()
   private async refreshAppAccessToken(): Promise<void> {
     if (!this.appAccessTokenInProgress) {
       this.logger.debug("refreshing spotify app access token");