tagged-keyv-wrapper

A powerful extension of @keyvhq/core that adds tag-based cache invalidation and management capabilities to the Keyv ecosystem.

Features

• 🔄 Drop-in replacement for @keyvhq/core with full backward compatibility
• 🏷️ Tag-based invalidation - Organize cache entries with tags and invalidate them in bulk
• ⚡ Memory efficient - Automatic compaction and dead key removal
• 🔒 Concurrency safe - Built-in locking prevents race conditions
• 🧩 Extensible architecture - Pluggable TagManager interface for different storage backends
• 📝 Full TypeScript support - Complete type safety with generics

Installation

npm install tagged-keyv-wrapper @keyvhq/core
# or
bun add tagged-keyv-wrapper @keyvhq/core

Quick Start

import Keyv from '@keyvhq/core';
import { TaggedKeyv } from 'tagged-keyv-wrapper';

// Create a @keyvhq/core instance (any storage adapter works)
const keyv = new Keyv();

// Create TaggedKeyv instance
const cache = new TaggedKeyv(keyv); // Or new TaggedKeyv() for in-memory default

// Use it exactly like @keyvhq/core
await cache.set('user:123', { name: 'John' });
const user = await cache.get('user:123');

// PLUS tag functionality
await cache.set('user:123', { name: 'John' }, { 
  ttl: 3600, 
  tags: ['users', 'active'] 
});

// Invalidate all users at once
await cache.invalidateTag('users');

API Reference

Core Methods (Keyv Compatible)

// Set a value (backward compatible)
await cache.set(key: string, value: T, ttl?: number): Promise<void>

// Set a value with tags (new API)
await cache.set(key: string, value: T, options?: { 
  ttl?: number, 
  tags?: string[] 
}): Promise<void>

// Get a value
await cache.get<T>(key: string): Promise<T | undefined>

// Delete a key
await cache.delete(key: string): Promise<boolean>

// Check if key exists
await cache.has(key: string): Promise<boolean>

// Clear all data
await cache.clear(): Promise<void>

Tag Management

// Get all entries with a specific tag
await cache.getByTag<T>(tag: string, options?: { page?: number; limit?: number }): Promise<Array<[string, T]>>

// Get all unique tags
await cache.getAllTags(): Promise<string[]>

// Get all tags for a specific key
await cache.getTagsForKey(key: string): Promise<string[]>

// Invalidate all entries with a tag
await cache.invalidateTag(tag: string): Promise<void>

// Invalidate multiple tags
await cache.invalidateTags(tags: string[]): Promise<void>

// Bulk set operations
await cache.setMany(entries: Array<[string, T, string[]?]>): Promise<void>

// Compact tag arrays (remove dead keys)
await cache.compactTags(tags?: string[]): Promise<void>

Usage Examples

User Session Management

// Create sessions with tags
await cache.set('session:user1:web', { userId: 1, device: 'web' }, { 
  ttl: 3600, 
  tags: ['user:1', 'device:web', 'sessions'] 
});

await cache.set('session:user1:mobile', { userId: 1, device: 'mobile' }, { 
  ttl: 3600, 
  tags: ['user:1', 'device:mobile', 'sessions'] 
});

// Invalidate all sessions for user 1
await cache.invalidateTag('user:1');

// Get all web sessions
const webSessions = await cache.getByTag('device:web');

Product Catalog

// Add products with category tags
await cache.setMany([
  ['product:1', { name: 'Laptop', price: 999 }, ['electronics', 'computers']],
  ['product:2', { name: 'Phone', price: 699 }, ['electronics', 'mobile']],
  ['product:3', { name: 'Shirt', price: 29 }, ['clothing', 'apparel']]
]);

// Get all electronics
const electronics = await cache.getByTag('electronics');

// Clear all clothing items
await cache.invalidateTag('clothing');

Cache Warming

// Warm cache with frequently accessed data
const users = await database.getActiveUsers();
for (const user of users) {
  await cache.set(`user:${user.id}`, user, { 
    ttl: 1800, 
    tags: ['users', 'warmed', `role:${user.role}`] 
  });
}

// Clear warmed cache
await cache.invalidateTag('warmed');

Tag Introspection and Debugging

// Set up some data
await cache.set('user:123', { name: 'Alice', role: 'admin' }, {
  tags: ['users', 'role:admin', 'status:active']
});
await cache.set('session:abc', { userId: 123 }, {
  tags: ['sessions', 'device:web']
});

// Discover all tags in the system
const allTags = await cache.getAllTags();
console.log('All tags:', allTags);
// ['users', 'role:admin', 'status:active', 'sessions', 'device:web']

// Inspect tags for a specific key
const userTags = await cache.getTagsForKey('user:123');
console.log('User tags:', userTags);
// ['users', 'role:admin', 'status:active']

// Conditional operations based on tags
if (userTags.includes('role:admin')) {
  console.log('User has admin privileges');
}

// Debug cache state
for (const tag of allTags) {
  const entries = await cache.getByTag(tag);
  console.log(`Tag "${tag}" has ${entries.length} entries`);
}

// Check if a key has specific tags
const sessionTags = await cache.getTagsForKey('session:abc');
const isWebSession = sessionTags.includes('device:web');
const isMobileSession = sessionTags.includes('device:mobile');

Architecture

TaggedKeyv uses a pluggable architecture with separate concerns:

• TaggedKeyv - Main orchestrator class
• TagManager - Interface for tag metadata storage
• KeyvTagManager - Default implementation using @keyvhq/core for tag storage

Custom TagManager

import { TagManager } from 'tagged-keyv-wrapper';

class CustomTagManager implements TagManager {
  // Implement interface methods
  async addKeyToTag(key: string, tag: string): Promise<void> { /* ... */ }
  async removeKeyFromTag(key: string, tag: string): Promise<void> { /* ... */ }
  // ... other methods
}

// Use custom implementation
const cache = new TaggedKeyv(keyv, new CustomTagManager());

Development

Running Tests

bun test                # Run all tests
bun test --watch        # Watch mode
bun test --coverage     # With coverage

Building

bun run build          # Build TypeScript
bun run check-types     # Type checking
bun run dev            # Watch mode

Performance Considerations

• Memory efficiency: Automatic compaction removes dead keys and duplicates
• Concurrency: Built-in locking prevents race conditions on key operations
• Bulk operations: Use setMany() and invalidateTags() for better performance
• Tag cleanup: Call compactTags() periodically for optimal memory usage

Migration from Keyv

TaggedKeyv is a complete drop-in replacement for @keyvhq/core:

// Before
const keyv = new Keyv();
await keyv.set('key', 'value', 3600);

// After (no changes needed)
const cache = new TaggedKeyv(keyv);
await cache.set('key', 'value', 3600);

// Plus new functionality
await cache.set('key', 'value', { ttl: 3600, tags: ['tag1'] });

Community & Support

We're happy to help with any questions or issues you might have. Here are some ways to get support:

• GitHub Issues: For bug reports and feature requests, please use our GitHub Issues.
• Discord: Join our community on Discord for general discussion and support: https://discord.gg/RNDzuJcHTu

License

This project is licensed under the MIT License - see the LICENSE file for details.

Contributing

Please read CONTRIBUTING.md for details on our code of conduct, and the process for submitting pull requests to us.