@arraypress/edge-cache

Tiny Hono middleware that attaches Cache-Control headers to successful GETs so CDNs (Cloudflare, Fastly, Vercel) absorb repeat anonymous traffic the origin would otherwise handle.

Install

npm install @arraypress/edge-cache

Usage

import { edgeCache } from '@arraypress/edge-cache';

// Public store endpoints — cache at the edge for 5 minutes.
app.use('/api/store/*', edgeCache({ maxAge: 0, sMaxAge: 300 }));

// Branding config rarely changes — longer TTL is fine.
app.use('/api/public/branding', edgeCache({ maxAge: 0, sMaxAge: 3600 }));

Skip conditions

The middleware never sets Cache-Control when any of these are true:

• c.env.ENVIRONMENT === 'development' (override via devEnvVar / devEnvValue)
• Non-GET request
• Response status ≠ 200
• Downstream handler has already set Cache-Control

This is deliberate: dev-mode edits should be immediately visible; error responses should never pin at the edge; per-route opt-outs work by just setting a conflicting header in the handler.

Options

| Option | Default | What | |---|---|---| | maxAge | 0 | Browser cache seconds. 0 means don't cache at the browser (admin edits always visible to the authoring user). | | sMaxAge | 60 | Edge cache seconds. | | directive | 'public' | Leading directive. Change to 'private' for per-user caching or 'public, must-revalidate' for stale-while-revalidate semantics. | | devEnvVar | 'ENVIRONMENT' | Env var name checked for the dev skip. | | devEnvValue | 'development' | Value that marks dev mode. |

Why this exists

Every Hono-on-Workers app writes this exact middleware. Setting s-maxage=60 on anonymous GET endpoints is the single most effective lever on D1 read quota — once the CDN absorbs repeat hits, the origin only handles unique-user traffic.

License

MIT