Cache

Aerostack Cache is backed by Cloudflare KV — a globally replicated key-value store with sub-millisecond read latency at the edge.

Quick start

import { sdk } from '@aerostack/sdk'
 
// Set a value with TTL
await sdk.cache.set('user:profile:123', userData, { ttl: 3600 }) // 1 hour
 
// Get a value
const cached = await sdk.cache.get('user:profile:123')
if (!cached) {
  // Cache miss — fetch from DB
}
 
// Delete
await sdk.cache.delete('user:profile:123')

Methods

Method	Description
`sdk.cache.set(key, value, options?)`	Store a value
`sdk.cache.get(key)`	Retrieve a value (`null` if missing or expired)
`sdk.cache.delete(key)`	Remove a key
`sdk.cache.has(key)`	Check if a key exists

Options

await sdk.cache.set(key, value, {
  ttl: 300,          // seconds until expiry (default: no expiry)
  metadata: {        // optional metadata stored alongside the value
    userId: '123',
    source: 'db'
  }
})

Cache-aside pattern

async function getUser(userId: string) {
  const cacheKey = `user:${userId}`
 
  // 1. Try cache
  const cached = await sdk.cache.get(cacheKey)
  if (cached) return cached
 
  // 2. Fetch from DB
  const user = await sdk.db.queryOne(
    'SELECT * FROM users WHERE id = ?',
    [userId]
  )
 
  // 3. Cache the result
  if (user) {
    await sdk.cache.set(cacheKey, user, { ttl: 300 })
  }
 
  return user
}

Cache invalidation

// On profile update, invalidate the cached profile
async function updateUser(userId: string, updates: object) {
  await sdk.db.query(
    'UPDATE users SET name = ? WHERE id = ?',
    [updates.name, userId]
  )
 
  // Invalidate cache
  await sdk.cache.delete(`user:${userId}`)
}

Cloudflare KV has eventual consistency — writes may take up to 60 seconds to propagate globally. For strong consistency requirements, use the database directly.

Streaming Overview