Serverless Eventbridge Scheduler Plugin

Serverless plugin to use Eventbridge Scheduler to schedule Lambda functions instead of Cloudwatch and Eventbridge Rules

This plugin was created for us to slowly start transitioning some our workloads away Eventbridge rules into the new and shiny Eventbridge scheduler

Installation

yarn add -D serverless-eventbridge-schedule

Add to serverless plugins

plugins:
  - serverless-eventbridge-schedule

Usage

functions:
  hello:
    # ...function definition
    events:
      - evSchedule:
          rate: cron(* * * * ? *)

This will create a new event bridge schedule which will trigger your lambda and move you away from event bridge rules

Why?

• It's new
• It supports timezones out of the box and I wanna see it finally solve the Daylight Savings problem
• Star and raise issues if you end up using this and want the full document which I promised myself I would write

Configuration

The configuration is fairly similar to how schedules work as event sources. The following config will attach a schedule event and causes the function crawl to be called every 2 hours. The configuration allows you to attach multiple schedules to the same function. You can either use the rate or cron syntax. Take a look at the AWS schedule syntax documentation for more details.

functions:
  crawl:
    handler: crawl
    events:
      - schedule: rate(2 hours)
      - schedule: cron(0 12 * * ? *)

Enabling / Disabling

Note: eVschedule events are enabled by default.

This will create and attach a schedule event for the aggregate function which is disabled. If enabled it will call the aggregate function every 10 minutes.

functions:
  aggregate:
    handler: statistics.handler
    events:
      - schedule:
          rate: rate(10 minutes)
          enabled: false
          input:
            key1: value1
            key2: value2
            stageParams:
              stage: dev
      - schedule:
          rate: cron(0 12 * * ? *)
          enabled: false
          inputPath: '$.stageVariables'
      - schedule:
          rate: rate(2 hours)
          enabled: true
          inputTransformer:
            inputPathsMap:
              eventTime: '$.time'
            inputTemplate: '{"time": <eventTime>, "key1": "value1"}'

Specify Name and Description

Name and Description can be specified for a schedule event. These are not required properties.

events:
  - schedule:
      name: your-scheduled-rate-event-name
      description: 'your scheduled rate event description'
      rate: rate(2 hours)

Specify multiple schedule expressions

An array of schedule expressions (i.e. using either rate or cron syntax) can be specified, in order to avoid repeating other configuration variables. This is specially useful in situations in which there's no other way than using multiple cron expressions to schedule a function.

This will trigger the function at certain times on weekdays and on different times on weekends, using the same input:

functions:
  foo:
    handler: foo.handler
    events:
      - schedule:
          rate:
            - cron(0 0/4 ? * MON-FRI *)
            - cron(0 2 ? * SAT-SUN *)
          input:
            key1: value1
            key2: value2

What's different then?

Input process is a bit different with Eventbridge scheduler, there's no way to specify an inputPath or an inputTransformer