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:

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

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

• :rocket: Distributed Execution: Run tasks across multiple environments.

• :alarm_clock: 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.