drive-index

Cloudflare Worker that watches a Google Drive folder for changes via webhooks, queues events, and syncs a complete file listing (name + ID) to a Google Sheet.

Architecture

Google Drive push notification
        │
        ▼
┌───────────────────────┐
│  Worker  POST /webhook│──► CF Queue (batched)
│          POST /setup  │         │
│          POST /stop   │         ▼
│          POST /reindex│    Queue consumer:
│          GET  /       │    reindex folder → write Sheet
└───────────────────────┘
        ▲
        │
  Cron (every 5 days) — renews watch channel (if WATCH_ENABLED)

Setup

1. Google Cloud Console

1. Go to Google Cloud Console and create a project (or use an existing one).

2. Enable APIs — go to APIs & Services → Library and enable:

   • Google Drive API
   • Google Sheets API

3. Create a Service Account:

   • Go to APIs & Services → Credentials
   • Click Create Credentials → Service Account
   • Name it (e.g. drive-index-worker)
   • No need to grant project-level roles
   • Click Done

4. Create a key for the Service Account:

   • Click on the service account you just created
   • Go to the Keys tab
   • Add Key → Create new key → JSON
   • Download the JSON file — you'll need its contents as a secret

5. Share the Drive folder with the service account:

   • Copy the service account email (e.g. drive-index-worker@project.iam.gserviceaccount.com)
   • Open the Google Drive folder you want to index
   • Click Share and add the service account email with Viewer access

6. Share the Google Sheet with the service account:

   • Create a new Google Sheet (or use an existing one)
   • Share it with the service account email with Editor access
   • Note the spreadsheet ID from the URL: https://docs.google.com/spreadsheets/d/<SPREADSHEET_ID>/edit

2. Cloudflare

1. Install Wrangler (if not already):

   pnpm install -g wrangler
   wrangler login

2. Create the Queue:

   wrangler queues create drive-index-events

3. Set secrets (deploy will fail if any are missing):

   # Paste the entire JSON key file contents when prompted
   wrangler secret put GOOGLE_SERVICE_ACCOUNT_KEY
   
   # Generate a random secret for webhook verification (use: openssl rand -hex 32)
   wrangler secret put WEBHOOK_SECRET
   
   # Google Drive folder ID (from URL: drive.google.com/drive/folders/<FOLDER_ID>)
   wrangler secret put FOLDER_ID
   
   # Google Sheet ID (from URL: docs.google.com/spreadsheets/d/<SPREADSHEET_ID>/edit)
   wrangler secret put SPREADSHEET_ID
   
   # Sheet tab name where file index will be written
   wrangler secret put SHEET_NAME
   
   # Public URL of the deployed worker
   wrangler secret put WORKER_URL

   Alternatively, set them all at once:

   echo '{"FOLDER_ID":"...","SPREADSHEET_ID":"...","SHEET_NAME":"...","WORKER_URL":"..."}' | wrangler secret bulk

4. Enable watching (optional) — set WATCH_ENABLED to "true" in wrangler.jsonc if you want the cron to auto-renew the Drive watch channel.

5. Deploy:

   pnpm deploy

3. Register the Drive watch channel

Once deployed, register the webhook so Google Drive sends push notifications:

curl -X POST https://drive-index.<your-subdomain>.workers.dev/setup \
  -H "Authorization: Bearer <your-webhook-secret>"

This creates a watch channel that expires in ~7 days. The cron trigger (every 5 days) automatically renews it while WATCH_ENABLED is "true".

4. Stopping the watch

Set WATCH_ENABLED to "false" in wrangler.jsonc and redeploy (or update via the CF dashboard). The cron will stop renewing the channel and it will expire within 7 days.

5. Manual reindex

To trigger a full reindex on demand:

curl -X POST https://drive-index.<your-subdomain>.workers.dev/reindex \
  -H "Authorization: Bearer <your-webhook-secret>"

Local development

pnpm install

# Interactive prompt — reads secrets.required from wrangler.jsonc
pnpm setup:local

pnpm dev

Tests

pnpm test

How it works

1. Webhook — Google Drive sends a POST to /webhook when files change in the watched folder. The worker verifies the request using the channel token and enqueues an event.

2. Queue consumer — CF Queue batches events (max 50 or 30s timeout). The consumer recursively lists all files in the folder and its subfolders via the Drive API, then replaces the sheet contents (from row 2 down) with file names in column A and IDs in column B.

3. Cron — Every 5 days, the scheduled handler renews the Drive watch channel (channels expire after ~7 days max). Only runs when WATCH_ENABLED is "true".

4. Reindex — POST /reindex triggers a manual full reindex without going through the queue.

API endpoints

Method	Path	Auth	Description
GET	/	None	Health check + watch status
POST	/webhook	x-goog-channel-token	Google Drive push notification receiver
POST	/setup	Bearer <secret>	Register Drive watch channel
POST	/stop	Bearer <secret>	Instructions to stop watching
POST	/reindex	Bearer <secret>	Trigger full reindex immediately

License

MIT