A Next.js (App Router) project intended for deployment to Cloudflare Workers using the OpenNext adapter, with a separate cron Worker that pre-fetches and caches ticker logos so visitors never call Massive/Polygon directly.

• Massive (Polygon.io): company branding images (logo/icon) for tickers (implemented).

• Runs on a cron schedule (configured in workers/refresh-logos-cron/wrangler.jsonc) and executes the Worker’s scheduled() handler.[8][9]
• For each run, processes a small batch of tickers (currently 1 ticker per run via MAX_TICKERS_PER_RUN = 1) using a KV cursor (cfg:cursor).
• For each ticker:
  • Calls Massive ticker overview endpoint to get branding.logo_url and/or branding.icon_url.
  • Downloads logo and icon (if available), chooses the smaller file, and stores the bytes in R2 (LOGOS_CACHE) at logos/<TICKER>.<ext>.
  • Stores metadata (not bytes) in KV (LOGO_META) at ticker:<TICKER>: { key, mime, bytes, source_url, updated_at }.
• Also writes operational keys into KV:
  • cfg:tickers (the canonical ticker list for the app)
  • lastRun and lastRunResult (debug/status)

Worker HTTP endpoints:

• Public:
  • GET /logo/<TICKER>: serves the cached bytes from R2 (no Massive calls).
• Admin (Bearer token):
  • GET /status: shows lastRun, lastRunResult, and which ticker:* keys exist.
  • GET /meta/<TICKER>: returns the KV metadata JSON.
  • GET /run: queues a refresh batch manually (dev/debug).

• API route GET /api/logos reads:
  • cfg:tickers + ticker:<TICKER> metadata from KV
  • corresponding image bytes from R2 using the stored key
• It returns a JSON payload of logos as data: URIs (base64) to keep the browser from needing direct R2 access.

• Cache ticker logos in R2 + store metadata in KV so clients never call Massive directly.

• pnpm create cloudflare@latest . --framework=next

• run these in workers/refresh-logos-cron
• Run: pnpm dlx wrangler dev --test-scheduled
• Trigger: http://localhost:8787/__scheduled (local scheduled test endpoint).[9]
• Verify KV: pnpm dlx wrangler kv key get "lastRun" --binding LOGO_META --remote --text

• R2 bucket: logos-cache (bound as LOGOS_CACHE)
• Workers KV namespace: LOGO_META
• LOGO_META_preview: previously used, now disconnected / not used

MASSIVE_API_KEY=...   # from Massive dashboard
ADMIN_TOKEN=...       # long random bearer token for /status, /run, /meta/* (you-make-this-up-reference)

LOGO_WORKER_BASE_URL=http://localhost:8787
LOGO_WORKER_ADMIN_TOKEN= # you-make-this-up-reference

Note: the current Next.js flow uses /api/logos (and reads KV/R2 directly via bindings) rather than calling the cron Worker over HTTP; these are mainly useful for debugging/admin endpoints and future expansions.

• Cron schedules run based on Cloudflare’s cron trigger configuration, and expressions are evaluated in UTC.[8]
• Type generation (for bindings) can be used to avoid TypeScript errors when referencing KVNamespace/R2Bucket bindings.