Stay effortlessly updated on your website's status—never miss a beat!
Important
Make sure you have tinygo installed as this project requires it to compile to WASM for Cloudflare Workers
1. Install dependencies
go mod tidy
2. Create a D1 database
npx wrangler d1 create gomon
3. Update the D1 binding values in the wrangler.jsonc file
"d1_databases": [
{
"binding": "DB",
"database_name": "gomon",
"database_id": "<YOUR_D1_DATABASE_ID>"
}
]
4. Fill in env variables in wrangler.jsonc file
"vars": {
"D1_BINDING": "DB",
"MIN_FREQUENCY": "", // in seconds
"WEBHOOK_NOTIFY_ON_RECOVERY": "true",
"WEBHOOK_MAX_ATTEMPTS": "3",
"WEBHOOK_INITIAL_DELAY_SEC": "30",
"WEBHOOK_MAX_DELAY_SEC": "300",
"WEBHOOK_BACKOFF_FACTOR": "2"
}
5. Run local migrations
npx wrangler d1 migrations apply gomon --local
6. Run the worker locally
npm start
7. Test cron scheduling locally
curl "http://127.0.0.1:8787/__scheduled"
.
├── src/ # go packages
├── main.go # entrypoint
├── wrangler.jsonc # cloudflare worker configuration
GoMon can send webhook callbacks when a website status transitions to degraded or down, and also on recovery to up.
Set webhook fields in the create or update request body:
{
"url": "https://example.com",
"frequency": 300,
"customHeaders": {
"Authorization": "Bearer your-token",
"X-Monitor-Source": "gomon"
},
"webhookEnabled": true,
"webhookUrl": "https://your-endpoint.example/webhook",
"webhookPayloadTemplate": "{\"id\":\"{{eventId}}\",\"url\":\"{{websiteUrl}}\",\"from\":\"{{previousStatus}}\",\"to\":\"{{currentStatus}}\",\"statusCode\":{{statusCode}},\"responseTime\":{{responseTime}},\"error\":\"{{error}}\",\"timestamp\":{{timestamp}}}"
}Sample request:
curl -X POST "http://127.0.0.1:8787/api/websites" \
-H "Content-Type: application/json" \
--data-raw '{
"url": "https://non-existent-website213131.com",
"frequency": 300,
"customHeaders": {
"Authorization": "Bearer your-token",
"X-Monitor-Source": "gomon"
},
"webhookEnabled": true,
"webhookUrl": "https://example.com/webhook",
"webhookPayloadTemplate": "{\"chat_id\":-1002500967676,\"message_thread_id\":51,\"title\":\"Alert for {{websiteUrl}}\",\"message\":\"from={{previousStatus}}, to={{currentStatus}}, statusCode={{statusCode}}, responseTime={{responseTime}}, error={{error}}, timestamp={{timestamp}}\"}"
}'Webhook retry/recovery behavior is global and configured through env vars in wrangler.jsonc.
Supported payload template placeholders:
{{eventId}}{{websiteUrl}}{{timestamp}}{{previousStatus}}{{currentStatus}}{{responseTime}}{{statusCode}}{{error}}
Webhook payload shape:
{
"eventId": "20260318120000.000000000-a1b2c3d4",
"websiteUrl": "https://example.com",
"timestamp": 1710777600,
"previousStatus": "up",
"currentStatus": "down",
"responseTime": 1534,
"statusCode": 502,
"error": ""
}