3.10. Scheduled Jobs

In this chapter, you’ll learn about scheduled jobs and how to use them.

What is a Scheduled Job?#

A scheduled job is a function executed at a specified interval of time in the background of your Medusa application. It’s like a cron job that runs during the application's runtime.

For example, you can synchronize your inventory with an Enterprise Resource Planning (ERP) system once a day using a scheduled job.

How to Create a Scheduled Job?#

A scheduled job is created in a TypeScript or JavaScript file under the src/jobs directory.

For example, create the file src/jobs/hello-world.ts with the following content:

1// the scheduled-job function2export default function () {3  console.log("Time to say hello world!")4}5
6// the job's configurations7export const config = {8  name: "every-minute-message",9  // execute every minute10  schedule: "* * * * *",11}

A scheduled job file must export:

  • A function to be executed whenever it’s time to run the scheduled job.
  • A configuration object defining the job. It has two properties:
    • name: a unique name for the job.
    • schedule: a cron expression specifying when to run the job.

This scheduled job executes every minute and logs into the terminal Time to say hello world!.

Test Scheduled Jobs#

To test out your scheduled job, start the Medusa application:

After a minute, the following message will be logged to the terminal:

Time to say hello world!

When to Use Scheduled Jobs#

Use scheduled jobs when
  • You're executing an action at a specified time interval during application runtime.
  • The action must be executed automatically.
Don't use scheduled jobs if
  • You want the action to execute at a specified time interval while the Medusa application isn't running. Instead, use the operating system's equivalent of a cron job.
  • You want to execute the action once. Use loaders instead.
  • You want to execute the action if an event occurs. Use subscribers instead.

Resolve Resources#

The scheduled job function receives a container parameter, which is the Medusa container. Use it to resolve resources in your Medusa application, such as services.

For example:

1import {2  IProductModuleService,3  MedusaContainer,4} from "@medusajs/types"5import { ModuleRegistrationName } from "@medusajs/utils"6
7export default async function myCustomJob(8  container: MedusaContainer9) {10  const productModuleService: IProductModuleService = 11    container.resolve(ModuleRegistrationName.PRODUCT)12
13  const [, count] = await productModuleService.listAndCountProducts()14
15  console.log(16    `Time to check products! You have ${count} product(s)`17  )18}19
20export const config = {21  name: "every-minute-message",22  // execute every minute23  schedule: "* * * * *",24}

In the scheduled job function, you resolve the Product Module's main service and retrieve the number of products in the store, then log the number in the terminal.

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