feat：添加Redis缓存服务

- 实现Redis服务接口和抽象层
- 提供真实Redis服务实现 (RealRedisService)
- 提供文件模拟Redis服务 (FileRedisService) 用于开发测试
- 支持基本的Redis操作：get、set、del、exists、ttl
- 添加Redis模块配置和依赖注入

src/core/redis/file-redis.service.ts

@@ -0,0 +1,204 @@
+import { Injectable, Logger } from '@nestjs/common';
+import { promises as fs } from 'fs';
+import * as path from 'path';
+import { IRedisService } from './redis.interface';
+
+/**
+ * 文件模拟Redis服务
+ * 在本地开发环境中使用文件系统模拟Redis功能
+ */
+@Injectable()
+export class FileRedisService implements IRedisService {
+  private readonly logger = new Logger(FileRedisService.name);
+  private readonly dataDir = path.join(process.cwd(), 'redis-data');
+  private readonly dataFile = path.join(this.dataDir, 'redis.json');
+  private data: Map<string, { value: string; expireAt?: number }> = new Map();
+
+  constructor() {
+    this.initializeStorage();
+  }
+
+  /**
+   * 初始化存储
+   */
+  private async initializeStorage(): Promise<void> {
+    try {
+      // 确保数据目录存在
+      await fs.mkdir(this.dataDir, { recursive: true });
+      
+      // 尝试加载现有数据
+      await this.loadData();
+      
+      // 启动过期清理任务
+      this.startExpirationCleanup();
+      
+      this.logger.log('文件Redis服务初始化完成');
+    } catch (error) {
+      this.logger.error('初始化文件Redis服务失败', error);
+    }
+  }
+
+  /**
+   * 从文件加载数据
+   */
+  private async loadData(): Promise<void> {
+    try {
+      const fileContent = await fs.readFile(this.dataFile, 'utf-8');
+      const jsonData = JSON.parse(fileContent);
+      
+      this.data = new Map();
+      for (const [key, item] of Object.entries(jsonData)) {
+        const typedItem = item as { value: string; expireAt?: number };
+        // 检查是否已过期
+        if (!typedItem.expireAt || typedItem.expireAt > Date.now()) {
+          this.data.set(key, typedItem);
+        }
+      }
+      
+      this.logger.log(`从文件加载了 ${this.data.size} 条Redis数据`);
+    } catch (error) {
+      // 文件不存在或格式错误，使用空数据
+      this.data = new Map();
+      this.logger.log('初始化空的Redis数据存储');
+    }
+  }
+
+  /**
+   * 保存数据到文件
+   */
+  private async saveData(): Promise<void> {
+    try {
+      const jsonData = Object.fromEntries(this.data);
+      await fs.writeFile(this.dataFile, JSON.stringify(jsonData, null, 2));
+    } catch (error) {
+      this.logger.error('保存Redis数据到文件失败', error);
+    }
+  }
+
+  /**
+   * 启动过期清理任务
+   */
+  private startExpirationCleanup(): void {
+    setInterval(() => {
+      this.cleanExpiredKeys();
+    }, 60000); // 每分钟清理一次过期键
+  }
+
+  /**
+   * 清理过期的键
+   */
+  private cleanExpiredKeys(): void {
+    const now = Date.now();
+    let cleanedCount = 0;
+    
+    for (const [key, item] of this.data.entries()) {
+      if (item.expireAt && item.expireAt <= now) {
+        this.data.delete(key);
+        cleanedCount++;
+      }
+    }
+    
+    if (cleanedCount > 0) {
+      this.logger.log(`清理了 ${cleanedCount} 个过期的Redis键`);
+      this.saveData(); // 保存清理后的数据
+    }
+  }
+
+  async set(key: string, value: string, ttl?: number): Promise<void> {
+    const item: { value: string; expireAt?: number } = { value };
+    
+    if (ttl && ttl > 0) {
+      item.expireAt = Date.now() + ttl * 1000;
+    }
+    
+    this.data.set(key, item);
+    await this.saveData();
+    
+    this.logger.debug(`设置Redis键: ${key}, TTL: ${ttl || '永不过期'}`);
+  }
+
+  async get(key: string): Promise<string | null> {
+    const item = this.data.get(key);
+    
+    if (!item) {
+      return null;
+    }
+    
+    // 检查是否过期
+    if (item.expireAt && item.expireAt <= Date.now()) {
+      this.data.delete(key);
+      await this.saveData();
+      return null;
+    }
+    
+    return item.value;
+  }
+
+  async del(key: string): Promise<boolean> {
+    const existed = this.data.has(key);
+    this.data.delete(key);
+    
+    if (existed) {
+      await this.saveData();
+      this.logger.debug(`删除Redis键: ${key}`);
+    }
+    
+    return existed;
+  }
+
+  async exists(key: string): Promise<boolean> {
+    const item = this.data.get(key);
+    
+    if (!item) {
+      return false;
+    }
+    
+    // 检查是否过期
+    if (item.expireAt && item.expireAt <= Date.now()) {
+      this.data.delete(key);
+      await this.saveData();
+      return false;
+    }
+    
+    return true;
+  }
+
+  async expire(key: string, ttl: number): Promise<void> {
+    const item = this.data.get(key);
+    
+    if (item) {
+      item.expireAt = Date.now() + ttl * 1000;
+      await this.saveData();
+      this.logger.debug(`设置Redis键过期时间: ${key}, TTL: ${ttl}秒`);
+    }
+  }
+
+  async ttl(key: string): Promise<number> {
+    const item = this.data.get(key);
+    
+    if (!item) {
+      return -2; // 键不存在
+    }
+    
+    if (!item.expireAt) {
+      return -1; // 永不过期
+    }
+    
+    const remaining = Math.ceil((item.expireAt - Date.now()) / 1000);
+    
+    if (remaining <= 0) {
+      // 已过期，删除键
+      this.data.delete(key);
+      await this.saveData();
+      return -2;
+    }
+    
+    return remaining;
+  }
+
+  async flushall(): Promise<void> {
+    this.data.clear();
+    await this.saveData();
+    this.logger.log('清空所有Redis数据');
+  }
+}