implement redis cache for context

src/Redis/redis.module.ts

@@ -0,0 +1,15 @@
+import { Global, Module } from '@nestjs/common';
+
+import { RedisService } from './redis.service';
+
+@Global()
+@Module({
+  providers: [
+    {
+      provide: 'REDIS_CLIENT',
+      useClass: RedisService,
+    },
+  ],
+  exports: ['REDIS_CLIENT'],
+})
+export class RedisModule {}

src/Redis/redis.service.ts

@@ -0,0 +1,41 @@
+import { Injectable } from '@nestjs/common';
+import { Redis } from 'ioredis';
+import { User } from '@prisma/client';
+
+@Injectable()
+export class RedisService {
+  private readonly redis: Redis;
+
+  constructor() {
+    this.redis = new Redis(process.env.REDIS_URL as string);
+  }
+
+  async get(key: string) {
+    return await this.redis.get(key);
+  }
+
+  async set(key: string, value: string, expireAt: number) {
+    return await this.redis.set(key, value, 'EXAT', expireAt);
+  }
+
+  async del(key: string) {
+    return await this.redis.del(key);
+  }
+
+  async close() {
+    return await this.redis.quit();
+  }
+
+  async getUser(sessionId: string) {
+    const userData = await this.get(sessionId);
+    if (!userData) {
+      return null;
+    }
+    const retrievedUser: User = JSON.parse(userData);
+    return retrievedUser;
+  }
+
+  async setUser(sessionId: string, user: User, expireAt: number) {
+    return await this.set(sessionId, JSON.stringify(user), expireAt);
+  }
+}