[Backend] API Caching Integration via Redis CacheManager

backend/src/common/config/cache.config.ts

@@ -0,0 +1,60 @@
+import { CacheModuleOptions, CacheStore } from '@nestjs/cache-manager';
+import { redisStore } from 'cache-manager-redis-yet';
+import { redisStore as redisIoStore } from 'cache-manager-ioredis';
+
+/**
+ * Cache configuration factory for NestJS CacheModule.
+ *
+ * Uses Redis as the backing store (shares existing REDIS_URL).
+ * Falls back to in-memory cache when Redis is not configured (dev mode).
+ *
+ * TTL defaults:
+ *   - Guilds leaderboard: 60s
+ *   - Bounties list: 30s
+ *   - General: 300s (5 min)
+ */
+export async function getCacheConfig(): Promise<CacheModuleOptions> {
+  const redisUrl = process.env.REDIS_URL;
+
+  if (!redisUrl || process.env.QUEUE_DISABLED === 'true') {
+    // Dev / no-Redis fallback: in-memory cache
+    return {
+      ttl: 5 * 1000, // 5 seconds default
+      max: 100,       // max cached items
+      isGlobal: true,
+    };
+  }
+
+  // Production: Redis-backed cache
+  let store: CacheStore;
+
+  try {
+    store = await redisStore({
+      url: redisUrl,
+      ttl: 60 * 1000, // default 60s
+      isGlobal: true,
+    });
+  } catch {
+    // Fallback to ioredis if primary driver unavailable
+    store = await redisIoStore({
+      url: redisUrl,
+      ttl: 60 * 1000,
+      isGlobal: true,
+    });
+  }
+
+  return {
+    store,
+    isGlobal: true,
+    ttl: 60 * 1000,
+  };
+}
+
+/** Predefined TTL constants (in seconds) */
+export const CACHE_TTL = {
+  GUILD_LEADERBOARD: 60,    // 1 minute — high-demand, changes rarely
+  BOUNTIES_LIST: 30,        // 30 seconds — moderate churn
+  GUILD_DETAILS: 120,       // 2 minutes
+  USER_PROFILE: 300,        // 5 minutes
+  DEFAULT: 300,             // 5 minutes fallback
+} as const;

backend/src/common/decorators/cache.decorator.ts

@@ -0,0 +1,16 @@
+import { applyDecorators, SetMetadata, CacheTTL } from '@nestjs/common';
+
+/** Custom metadata key for cache TTL override */
+export const CACHE_TTL_META_KEY = 'cache:ttl';
+
+/**
+ * Combined decorator: sets CacheKey + custom TTL metadata.
+ * Usage: @Cacheable('guilds:leaderboard', 60)
+ */
+export function Cacheable(key: string, ttlSeconds: number) {
+  return applyDecorators(
+    SetMetadata('CACHE_KEY', key),
+    SetMetadata(CACHE_TTL_META_KEY, ttlSeconds),
+    CacheTTL(ttlSeconds * 1000), // CacheTTL expects milliseconds
+  );
+}

backend/src/guild/guild.controller.ts

@@ -13,6 +13,8 @@ import {
   UseInterceptors,
   HttpCode,
   HttpStatus,
+  CacheKey,
+  CacheTTL,
 } from '@nestjs/common';
 import { FileInterceptor } from '@nestjs/platform-express';
 import { JwtAuthGuard } from '../auth/guards/jwt-auth.guard';
@@ -52,11 +54,15 @@ export class GuildController {
   }
 
   @Get('by-slug/:slug')
+  @CacheKey('guilds:slug')
+  @CacheTTL(120_000) // 2 minutes
   async getBySlug(@Param('slug') slug: string): Promise<GuildDetailsDto> {
     return this.guildService.getBySlug(slug);
   }
 
   @Get()
+  @CacheKey('guilds:search')
+  @CacheTTL(60_000) // 1 minute — high-demand endpoint
   async search(@Query() query: SearchGuildDto) {
     return this.guildService.searchGuilds(query.q, query.page, query.size);
   }