Vercel Cron Jobs

Vercel Cron Jobs require simple authorization using an environment variable. This can be achieved by creating a decorator that checks authorization header with a secret key.

src/decorators/cronGuard.ts


import { HttpException, HttpStatus, createDecorator } from 'vovk';
 
const cronGuard = createDecorator(async (req, next) => {
  if (req.headers.get('authorization') !== `Bearer ${process.env.CRON_SECRET}`) {
    throw new HttpException(HttpStatus.UNAUTHORIZED, 'Unauthorized');
  }
 
  return next();
});
 
export default cronGuard;

Apply the cronGuard decorator to the controller method that should be protected by the cron job authorization.

src/modules/cron/CronController.ts


import { get, prefix } from 'vovk';
import cronGuard from '../decorators/cronGuard';
 
@prefix('cron')
export default class CronController {
  @get('do-something')
  @cronGuard()
  static async doSomething() {
    // ...
  }
}

Add the cron job to the vercel.json file. The schedule field uses the cron syntax (at this case the cron job will run every day at midnight).

/vercel.json


{
  "crons": [
    {
      "path": "/api/cron/do-something",
      "schedule": "0 0 * * *"
    }
  ]
}