@ciscode/cachekit

Production-ready NestJS caching module with pluggable store adapters, a cache-aside service, and method-level @Cacheable / @CacheEvict decorators.

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📦 Installation

npm install @ciscode/cachekit

Peer dependencies

Install the peers that match what your app already uses:

# Always required
npm install @nestjs/common @nestjs/core

# Required when using the Redis store
npm install ioredis

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🚀 Quick Start

1. Register with an in-memory store (zero config)

import { Module } from "@nestjs/common";
import { CacheModule } from "@ciscode/cachekit";

@Module({
  imports: [
    CacheModule.register({
      store: "memory",
      ttl: 60, // default TTL in seconds (optional)
    }),
  ],
})
export class AppModule {}

2. Register with a Redis store

import { Module } from "@nestjs/common";
import { CacheModule } from "@ciscode/cachekit";

@Module({
  imports: [
    CacheModule.register({
      store: "redis",
      ttl: 300,
      redis: {
        client: "redis://localhost:6379",
        keyPrefix: "myapp:",
      },
    }),
  ],
})
export class AppModule {}

3. Register asynchronously (with ConfigService)

import { Module } from "@nestjs/common";
import { ConfigModule, ConfigService } from "@nestjs/config";
import { CacheModule } from "@ciscode/cachekit";

@Module({
  imports: [
    ConfigModule.forRoot(),
    CacheModule.registerAsync({
      imports: [ConfigModule],
      inject: [ConfigService],
      useFactory: (cfg: ConfigService) => ({
        store: cfg.get<"redis" | "memory">("CACHE_STORE", "memory"),
        ttl: cfg.get<number>("CACHE_TTL", 60),
        redis: {
          client: cfg.get<string>("REDIS_URL", "redis://localhost:6379"),
          keyPrefix: cfg.get<string>("CACHE_PREFIX", "app:"),
        },
      }),
    }),
  ],
})
export class AppModule {}

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🔧 CacheService API

Inject CacheService wherever you need direct cache access:

import { Injectable } from "@nestjs/common";
import { CacheService } from "@ciscode/cachekit";

@Injectable()
export class ProductsService {
  constructor(private readonly cache: CacheService) {}

  async getProduct(id: string) {
    // Manual cache-aside pattern
    const cached = await this.cache.get<Product>(`product:${id}`);
    if (cached) return cached;

    const product = await this.db.findProduct(id);
    await this.cache.set(`product:${id}`, product, 120); // TTL = 120 s
    return product;
  }

  async deleteProduct(id: string) {
    await this.db.deleteProduct(id);
    await this.cache.delete(`product:${id}`);
  }

  // wrap() — cache-aside in one call
  async getAll(): Promise<Product[]> {
    return this.cache.wrap(
      "products:all",
      () => this.db.findAllProducts(),
      300, // TTL = 300 s
    );
  }
}

Full method reference

Method	Signature	Description
get	get<T>(key): Promise<T | null>	Retrieve a value; returns null on miss or expiry
set	set<T>(key, value, ttl?): Promise<void>	Store a value; ttl overrides module default
delete	delete(key): Promise<void>	Remove a single entry
clear	clear(): Promise<void>	Remove all entries (scoped to key prefix for Redis)
has	has(key): Promise<boolean>	Return true if key exists and has not expired
wrap	wrap<T>(key, fn, ttl?): Promise<T>	Return cached value or call fn, cache result, return it

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🎯 Method Decorators

@Cacheable(key, ttl?)

Cache the return value of a method automatically (cache-aside). The decorated method is only called on a cache miss; subsequent calls return the stored value.

Key templates — use {0}, {1}, … to interpolate method arguments:

import { Injectable } from "@nestjs/common";
import { Cacheable } from "@ciscode/cachekit";

@Injectable()
export class UserService {
  // Static key — same result cached for all calls
  @Cacheable("users:all", 300)
  async findAll(): Promise<User[]> {
    return this.db.findAllUsers();
  }

  // Dynamic key — "user:42" for userId = 42
  @Cacheable("user:{0}", 120)
  async findById(userId: number): Promise<User> {
    return this.db.findUser(userId);
  }

  // Multi-argument key — "org:5:user:99"
  @Cacheable("org:{0}:user:{1}", 60)
  async findByOrg(orgId: number, userId: number): Promise<User> {
    return this.db.findUserInOrg(orgId, userId);
  }
}

@CacheEvict(key)

Evict (delete) a cache entry after the decorated method completes successfully. If the method throws, the entry is not evicted.

import { Injectable } from "@nestjs/common";
import { CacheEvict } from "@ciscode/cachekit";

@Injectable()
export class UserService {
  // Evict "users:all" whenever a user is created
  @CacheEvict("users:all")
  async createUser(dto: CreateUserDto): Promise<User> {
    return this.db.createUser(dto);
  }

  // Evict the specific user entry — "user:42" for userId = 42
  @CacheEvict("user:{0}")
  async updateUser(userId: number, dto: UpdateUserDto): Promise<User> {
    return this.db.updateUser(userId, dto);
  }

  // Evict on delete
  @CacheEvict("user:{0}")
  async deleteUser(userId: number): Promise<void> {
    await this.db.deleteUser(userId);
  }
}

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⚙️ Configuration reference

CacheModuleOptions (synchronous)

Field	Type	Required	Default	Description
store	"memory" | "redis"	✅	—	Backing store adapter
ttl	number	❌	undefined	Default TTL in seconds for all set() calls
redis	RedisCacheStoreOptions	When store: "redis"	—	Redis connection config

RedisCacheStoreOptions

Field	Type	Required	Description
client	string | Redis	✅	Redis URL (redis://…) or existing ioredis instance
keyPrefix	string	❌	Prefix for all keys, e.g. "myapp:"

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🏗️ Architecture

src/
  ├── index.ts                                  # Public API exports
  ├── cache-kit.module.ts                       # CacheModule (dynamic NestJS module)
  ├── constants.ts                              # DI tokens: CACHE_STORE, CACHE_MODULE_OPTIONS
  │
  ├── ports/
  │   └── cache-store.port.ts                  # ICacheStore interface
  │
  ├── adapters/
  │   ├── in-memory-cache-store.adapter.ts     # Map-backed adapter (no deps)
  │   └── redis-cache-store.adapter.ts         # ioredis-backed adapter
  │
  ├── services/
  │   └── cache.service.ts                     # CacheService (public API)
  │
  ├── decorators/
  │   ├── cacheable.decorator.ts               # @Cacheable
  │   └── cache-evict.decorator.ts             # @CacheEvict
  │
  └── utils/
      ├── cache-service-ref.ts                 # Singleton holder for decorators
      └── resolve-cache-key.util.ts            # {0}, {1} key template resolver

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🔐 Security notes

• Never pass credentials directly in source code — use environment variables or ConfigService
• The Redis keyPrefix isolates cache entries from other apps sharing the same instance
• clear() without a key prefix will FLUSHDB the entire Redis database — use prefixes in production

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📄 License

MIT © CisCode

3. Define DTOs

// src/dto/create-example.dto.ts
import { IsString, IsNotEmpty } from "class-validator";

export class CreateExampleDto {
  @IsString()
  @IsNotEmpty()
  name: string;
}

4. Export Public API

// src/index.ts
export { ExampleKitModule } from "./example-kit.module";
export { ExampleService } from "./services/example.service";
export { CreateExampleDto } from "./dto/create-example.dto";

📝 Scripts

# Development
npm run build          # Build the package
npm run build:watch    # Build in watch mode
npm run typecheck      # TypeScript type checking

# Testing
npm test               # Run tests
npm run test:watch     # Run tests in watch mode
npm run test:cov       # Run tests with coverage

# Code Quality
npm run lint           # Run ESLint
npm run format         # Check formatting
npm run format:write   # Fix formatting

# Release
npx changeset          # Create a changeset
npm run release        # Publish to npm (CI does this)

🔄 Release Workflow

This template uses Changesets for version management.

1. Create a Feature

git checkout develop
git checkout -b feature/my-feature
# Make your changes

2. Create a Changeset

npx changeset

Select the change type:

• patch - Bug fixes
• minor - New features (backwards compatible)
• major - Breaking changes

3. Commit and PR

git add .
git commit -m "feat: add new feature"
git push origin feature/my-feature
# Create PR → develop

4. Release

• Automation opens "Version Packages" PR
• Merge to master to publish

🧪 Testing

Tests are MANDATORY for all public APIs.

// src/services/example.service.spec.ts
describe("ExampleService", () => {
  let service: ExampleService;

  beforeEach(async () => {
    const module = await Test.createTestingModule({
      providers: [ExampleService],
    }).compile();

    service = module.get(ExampleService);
  });

  it("should be defined", () => {
    expect(service).toBeDefined();
  });

  it("should process data correctly", async () => {
    const result = await service.doSomething("test");
    expect(result).toBe("Processed: test");
  });
});

Coverage threshold: 80%

📚 Path Aliases

Configured in tsconfig.json:

import { ExampleService } from "@services/example.service";
import { CreateExampleDto } from "@dtos/create-example.dto";
import { Example } from "@entities/example.entity";
import { ExampleRepository } from "@repos/example.repository";

Available aliases:

• @/* → src/*
• @controllers/* → src/controllers/*
• @services/* → src/services/*
• @entities/* → src/entities/*
• @repos/* → src/repositories/*
• @dtos/* → src/dto/*
• @guards/* → src/guards/*
• @decorators/* → src/decorators/*
• @config/* → src/config/*
• @utils/* → src/utils/*

🔒 Security Best Practices

• ✅ Input validation on all DTOs (class-validator)
• ✅ Environment variables for secrets
• ✅ No hardcoded credentials
• ✅ Proper error handling
• ✅ Rate limiting on public endpoints

🤖 AI-Friendly Development

This template includes comprehensive Copilot instructions in .github/copilot-instructions.md:

• Module architecture guidelines
• Naming conventions
• Testing requirements
• Documentation standards
• Export patterns
• Security best practices

📖 Documentation

• Architecture - Detailed architecture overview
• Release Process - How to release versions
• Copilot Instructions - AI development guidelines

🛠️ Customization

1. Rename the module: Update package.json name
2. Update description: Modify package.json description
3. Configure exports: Edit src/index.ts
4. Add dependencies: Update peerDependencies and dependencies
5. Customize structure: Add/remove directories as needed

⚠️ Important Notes

What to Export

✅ DO export:

• Module
• Services
• DTOs
• Guards
• Decorators
• Types/Interfaces

❌ DON'T export:

• Entities
• Repositories

Entities and repositories are internal implementation details.

Versioning

• MAJOR (x.0.0) - Breaking changes
• MINOR (0.x.0) - New features (backwards compatible)
• PATCH (0.0.x) - Bug fixes

📋 Checklist Before Publishing

• All tests passing (80%+ coverage)
• No ESLint warnings
• TypeScript strict mode passing
• All public APIs documented (JSDoc)
• README updated
• Changeset created
• Breaking changes documented
• .env.example updated (if needed)

📄 License

MIT

🤝 Contributing

See CONTRIBUTING.md

🆘 Support

• Documentation
• GitHub Issues
• Discussions

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Made with ❤️ by CisCode