impl friends system

projects/common/src/cache.ts

@@ -0,0 +1,129 @@
+type CacheOptions = {
+  /**
+   * The time the cached object will be valid for
+   */
+  ttl?: number;
+
+  /**
+   * How often to check for expired objects
+   */
+  checkInterval?: number;
+
+  /**
+   * Enable debug messages
+   */
+  debug?: boolean;
+};
+
+type CachedObject = {
+  /**
+   * The cached object
+   */
+  value: any;
+
+  /**
+   * The timestamp the object was cached
+   */
+  timestamp: number;
+};
+
+export class SSRCache {
+  /**
+   * The time the cached object will be valid for
+   * @private
+   */
+  private readonly ttl: number | undefined;
+
+  /**
+   * How often to check for expired objects
+   * @private
+   */
+  private readonly checkInterval: number | undefined;
+
+  /**
+   * Enable debug messages
+   * @private
+   */
+  private readonly debug: boolean;
+
+  /**
+   * The objects that have been cached
+   * @private
+   */
+  private cache = new Map<string, CachedObject>();
+
+  constructor({ ttl, checkInterval, debug }: CacheOptions) {
+    this.ttl = ttl;
+    this.checkInterval = checkInterval || this.ttl ? 1000 * 60 : undefined; // 1 minute
+    this.debug = debug || false;
+
+    if (this.ttl !== undefined && this.checkInterval !== undefined) {
+      setInterval(() => {
+        for (const [key, value] of this.cache.entries()) {
+          if (value.timestamp + this.ttl! > Date.now()) {
+            continue;
+          }
+          this.remove(key);
+        }
+      }, this.checkInterval);
+    }
+  }
+
+  /**
+   * Gets an object from the cache
+   *
+   * @param key the cache key for the object
+   */
+  public get<T>(key: string): T | undefined {
+    const cachedObject = this.cache.get(key);
+    if (cachedObject === undefined) {
+      if (this.debug) {
+        console.log(`Cache miss for key: ${key}`);
+      }
+      return undefined;
+    }
+    if (this.debug) {
+      console.log(`Retrieved ${key} from cache, value: ${JSON.stringify(cachedObject)}`);
+    }
+    return cachedObject.value as T;
+  }
+
+  /**
+   * Sets an object in the cache
+   *
+   * @param key the cache key
+   * @param value the object
+   */
+  public set<T>(key: string, value: T): void {
+    this.cache.set(key, {
+      value,
+      timestamp: Date.now(),
+    });
+
+    if (this.debug) {
+      console.log(`Inserted ${key} into cache, value: ${JSON.stringify(value)}`);
+    }
+  }
+
+  /**
+   * Checks if an object is in the cache
+   *
+   * @param key the cache key
+   */
+  public has(key: string): boolean {
+    return this.cache.has(key);
+  }
+
+  /**
+   * Removes an object from the cache
+   *
+   * @param key the cache key
+   */
+  public remove(key: string): void {
+    this.cache.delete(key);
+
+    if (this.debug) {
+      console.log(`Removed ${key} from cache`);
+    }
+  }
+}

projects/common/src/service/impl/scoresaber.ts

@@ -8,6 +8,7 @@ import ScoreSaberLeaderboardToken from "../../types/token/scoresaber/score-saber
 import ScoreSaberLeaderboardScoresPageToken from "../../types/token/scoresaber/score-saber-leaderboard-scores-page-token";
 import { clamp, lerp } from "../../utils/math-utils";
 import { CurvePoint } from "../../utils/curve-point";
+import { SSRCache } from "../../cache";
 
 const API_BASE = "https://scoresaber.com/api";
 
@@ -28,6 +29,10 @@ const LOOKUP_LEADERBOARD_SCORES_ENDPOINT = `${API_BASE}/leaderboard/by-id/:id/sc
 
 const STAR_MULTIPLIER = 42.117208413;
 
+const playerCache = new SSRCache({
+  ttl: 60 * 30, // 30 minutes
+});
+
 class ScoreSaberService extends Service {
   private curvePoints = [
     new CurvePoint(0, 0),
@@ -98,9 +103,13 @@ class ScoreSaberService extends Service {
    * Looks up a player by their ID.
    *
    * @param playerId the ID of the player to look up
+   * @param cache whether to use the local cache
    * @returns the player that matches the ID, or undefined
    */
-  public async lookupPlayer(playerId: string): Promise<ScoreSaberPlayerToken | undefined> {
+  public async lookupPlayer(playerId: string, cache: boolean = false): Promise<ScoreSaberPlayerToken | undefined> {
+    if (cache && playerCache.has(playerId)) {
+      return playerCache.get(playerId);
+    }
     const before = performance.now();
     this.log(`Looking up player "${playerId}"...`);
     const token = await this.fetch<ScoreSaberPlayerToken>(LOOKUP_PLAYER_ENDPOINT.replace(":id", playerId));
@@ -108,6 +117,9 @@ class ScoreSaberService extends Service {
       return undefined;
     }
     this.log(`Found player "${playerId}" in ${(performance.now() - before).toFixed(0)}ms`);
+    if (cache) {
+      playerCache.set(playerId, token);
+    }
     return token;
   }