# AWS Node Scheduled Cron Example This is an example of creating a function that runs as a cron job using the serverless `schedule` event. For more information on `schedule` event check out the Serverless docs on [schedule](https://serverless.com/framework/docs/providers/aws/events/schedule/). Schedule events use the `rate` or `cron` syntax. ## Rate syntax ```pseudo rate(value unit) ``` `value` - A positive number `unit` - The unit of time. ( minute | minutes | hour | hours | day | days ) **Example** `rate(5 minutes)` For more [information on the rate syntax see the AWS docs](http://docs.aws.amazon.com/AmazonCloudWatch/latest/events/ScheduledEvents.html#RateExpressions) ## Cron syntax ```pseudo cron(Minutes Hours Day-of-month Month Day-of-week Year) ``` All fields are required and time zone is UTC only. | Field | Values | Wildcards | | ------------- |:--------------:|:-------------:| | Minutes | 0-59 | , - * / | | Hours | 0-23 | , - * / | | Day-of-month | 1-31 | , - * ? / L W | | Month | 1-12 or JAN-DEC| , - * / | | Day-of-week | 1-7 or SUN-SAT | , - * ? / L # | | Year | 1970-2199 | , - * / | Read the [AWS cron expression syntax](http://docs.aws.amazon.com/lambda/latest/dg/tutorial-scheduled-events-schedule-expressions.html) docs for more info on how to setup cron ## Deploy In order to deploy the you endpoint simply run ```bash serverless deploy ``` The expected result should be similar to: ```bash Serverless: Packaging service... Serverless: Uploading CloudFormation file to S3... Serverless: Uploading service .zip file to S3 (1.47 KB)... Serverless: Updating Stack... Serverless: Checking Stack update progress... .............. Serverless: Stack update finished... Service Information service: scheduled-cron-example stage: dev region: us-east-1 api keys: None endpoints: None functions: scheduled-cron-example-dev-cron: arn:aws:lambda:us-east-1:377024778620:function:scheduled-cron-example-dev-cron scheduled-cron-example-dev-secondCron: arn:aws:lambda:us-east-1:377024778620:function:scheduled-cron-example-dev-secondCron ``` There is no additional step required. Your defined schedule becomes active right away after deployment. ## Usage To see your cron job running tail your logs with: ```bash serverless logs --function cron --tail ``` The expected result should be similar to: ```bash START RequestId: e6e64a4e-b57d-11e6-9eee-0340b40f6d48 Version: $LATEST 2016-11-28 16:18:23.755 (+01:00) e6e64a4e-b57d-11e6-9eee-0340b40f6d48 Your cron function "scheduled-cron-example-dev-cron" ran at Mon Nov 28 2016 15:18:23 GMT+0000 (UTC) END RequestId: e6e64a4e-b57d-11e6-9eee-0340b40f6d48 REPORT RequestId: e6e64a4e-b57d-11e6-9eee-0340b40f6d48 Duration: 4.01 ms Billed Duration: 100 ms Memory Size: 1024 MB Max Memory Used: 16 MB START RequestId: 0a770e6f-b57e-11e6-ba68-f188460981c7 Version: $LATEST 2016-11-28 16:19:22.921 (+01:00) 0a770e6f-b57e-11e6-ba68-f188460981c7 Your cron function "scheduled-cron-example-dev-cron" ran at Mon Nov 28 2016 15:19:22 GMT+0000 (UTC) END RequestId: 0a770e6f-b57e-11e6-ba68-f188460981c7 REPORT RequestId: 0a770e6f-b57e-11e6-ba68-f188460981c7 Duration: 0.69 ms Billed Duration: 100 ms Memory Size: 1024 MB Max Memory Used: 16 MB ``` Since this only shows you the logs of the first cron job simply change the function name and run the command again: ```bash serverless logs --function secondCron --tail ``` ## Additonal Resources For more information on running cron with Serverless check out the [Tutorial: Serverless Scheduled Tasks](https://parall.ax/blog/view/3202/tutorial-serverless-scheduled-tasks) by Parallax.