Scheduler

This guide explains how to configure and use Platformatic's built-in scheduler. The scheduler allows you to run periodic tasks by making HTTP requests at scheduled intervals using cron expressions. Note that the scheduler is in-memory only, so no information is persisted between restarts.

Overview

The Platformatic scheduler enables you to configure automated HTTP requests that run according to a specified schedule. This feature is useful for:

• Periodic data synchronization
• Scheduled maintenance tasks
• Recurring API calls
• Implementing workflows that need to run at specific times

Configuration

The scheduler is configured using an array of job definitions in your Platformatic configuration file.

Here's a basic example:

//...
  "scheduler": [
    {
      "name": "my-scheduled-job",
      "cron": "*/5 * * * *",
      "callbackUrl": "http://localhost:3042/my-endpoint",
      "method": "GET"
    }
  ]

//...

Job Configuration Options

Each job in the scheduler can include the following options:

Option	Type	Required	Description
name	String	Yes	A unique identifier for the job
cron	String	Yes	A cron expression defining the schedule
callbackUrl	String	Yes	The URL to call when the job is triggered
enabled	Boolean	No (defaults to true)	If false, the job is disabled.
method	String	No (defaults to 'GET')	HTTP method to use (GET, POST, PUT, DELETE)
headers	Object	No	HTTP headers to include in the request
body	String / Object	No	Request body (for POST/PUT requests)
maxRetries	Number	No (defaults to 3)	Number of retries attempts

Cron Expression Format

The scheduler uses standard cron expressions with an optional seconds field. Examples:

• */1 * * * * * - Every second
• 0 */5 * * * * - Every 5 minutes
• 0 0 * * * * - Every hour
• 0 0 12 * * * - Every day at noon
• 0 0 0 * * 1 - Every Monday at midnight

See crontab.guru for more examples.

Example: call application in the mesh network

It is possible (and useful) to call also applications in the platformatic mesh network. Here's an example configuring a job that sends a POST request every minute to an internal notification application (so exposed as http://notification.plt.local in the mesh network).

//...
  "scheduler": [
      {
        "name": "send-message",
        "cron": "0 */1 * * * *",
        "callbackUrl": "http://notification.plt.local/message",
        "method": "POST",
        "headers": {
          "content-type": "application/json",
        },
        "body": {
          "message": "Scheduled notification",
          "type": "info"
        }
      }
    ]
  //..