Kronos - Cron Job Webhook Scheduler

Overview

Kronos is a powerful cron job webhook scheduler that allows you to define and manage scheduled tasks with ease. Utilizing a simple JSON-like DSL, Kronos makes it easy to schedule webhooks and automate workflows seamlessly.

Features:

• ✨ Simple DSL: Define your workflows using a clear, JSON-like syntax.

• ⚡ REST API Integration: Schedule and manage webhooks easily.

• 🚀 Distributed Execution: Run tasks across multiple environments.

• ⏰ Flexible Scheduling: Create complex scheduling patterns with cron expressions.

Build (Go 1.9+)

Run the following command

foo@bar$ make build

to build an executable which will be output to the bin subfolder.

Yaml file configuration

logging:
  level: INFO
  format: JSON

port: 9175

store:
  path: "/path/to/db/file" # default is kronos.bolt

Docker compose configuration

services:
  kronos:
    image: ghcr.io/ostafen/kronos
    ports:
      - '9175:9175'
    environment:
      - PORT=9175 # configuration properties can be overridden through environment variables
      - STORE_PATH=/data/kronos.bolt
    volumes:
      - ./data:/data

Registering a periodic schedule

To start getting some webhook notifications, let's add a new schedule which will be notified every minute:

curl -X POST localhost:9175/schedules -H 'Content-Type: application/json' -d \
'{
    "title": "sample-schedule",
    "description": "a sample schedule description",
    "cronExpr": "0/1 * * * *",
    "url": "your-webhook-address",
    "isRecurring": true,
    "startAt": "2023-02-19T11:34:00Z",
    "endAt": "2023-02-19T11:38:00Z"
}'

On success, the response of the server will be similar to the following:

{
    "id": "1e6d146b-e3b7-4e5c-b7ce-b7b2860f461b",
    "title": "sample-schedule",
    "status": "not_started",
    "description": "a sample schedule description",
    "cronExpr": "0/1 * * * *",
    "url": "your-webhook-address",
    "metadata": null,
    "isRecurring": true,
    "createdAt": "2023-02-19T12:32:30.788562107+01:00",
    "runAt": "0001-01-01T00:00:00Z",
    "startAt": "2023-02-19T11:34:00Z",
    "endAt": "2023-02-19T11:38:00Z",
    "nextScheduleAt": "2023-02-19T11:34:00Z",
}

The above table contains the full list of supported fields:

Parameter	Required	Description
title	true	the name of your schedule. It must be unique.
description	false	an optional description of your schedule.
isRecurring	false	whether the schedule is recurring or not.
cronExpr	if isRecurring = true	cron expression for recurring schedules.
url	true	webhook notification endpoint.
runAt	if isRecurring = false	for non-recurring schedules, it indicates the instant the schedule will be triggered at.
startAt	false	UTC start date of the schedule. Must be equal to runAt if isRecurring = false.
endAt	false	UTC end date of the schedule. Must be equal to runAt if isRecurring = false.
metadata	false	optional metadata which will be sent when triggering a webhook.

REST API

• POST /schedules - Register a new schedule
• GET /schedules/{id} - Get details about an already existing schedule
• DELETE /schedules/{id} - Delete a schedule
• POST /schedules/{id}/pause - Pause an active schedule
• POST /schedules/{id}/resume - Resume a paused schedule
• POST /schedules/{id}/trigger - Immediately trigger a notification for a given schedule

Contact

Stefano Scafiti @ostafen

License

Kronos source code is available under the MIT License.