Serverless Workflows with AWS Step Functions and Amazon EventBridge Scheduler

Author Picture

Wagner Caetano

July 8, 2023

Post Picture

Introduction

In today's fast-paced digital landscape, the need for efficient and automated workflows is paramount. Serverless architectures have gained popularity due to their scalability and cost-effectiveness. AWS Step Functions and Amazon EventBridge Scheduler are powerful services provided by Amazon Web Services (AWS) that enable the automation of serverless workflows. In this article, I will show you the process of using these services and learn how to leverage their capabilities to automate and streamline your serverless workflows.

What are AWS Step Functions?

AWS Step Functions is a fully managed service that allows you to coordinate and orchestrate multiple AWS services into serverless workflows. With Step Functions, you can visually design and execute complex workflows using a state machine-based approach. It simplifies the coordination between different components and services, making it easier to build scalable and resilient applications.


Getting Started with AWS Step Functions

To begin automating your serverless workflows with AWS Step Functions, follow these steps:

Step 1: Design your workflow

Using the Step Functions console or the AWS CloudFormation template, define the states and transitions that make up your workflow. Each state represents a specific task or activity within your application. You can choose from various state types such as Task, Choice, Wait, and Parallel, depending on the logic and requirements of your workflow.

Worflow Studio

image

Here as you can see we have a Workflow Studio screenshot from a recent project I've worked on for college, in this case we have 2 lambda function invocations, a couple of error handling states and a Wait State. This workflow purpose is to add data on a DynamoDB database after given time is passed.

Step 2: Define input and output data

Specify the input and output data for each state in your workflow. Input data provides the necessary information for a state to execute, while output data captures the results or outputs generated by a state. This data can be passed between states, enabling seamless coordination and communication.

Step 3: Configure state transitions

Configure the transitions between states to define the flow of your workflow. You can use conditions and branching logic to determine which path the workflow should take based on specific criteria. This flexibility allows you to handle different scenarios and conditions within your serverless workflow.

Beyond just conditions and logic, you can add error handling for multiple scenarios, both expected and not expected. Allowing you to retry if necessary on a given error scenario.

Step 4: Implement state logic

For each state in your workflow, define the logic and actions that need to be performed. This can include invoking AWS Lambda functions, executing AWS Glue jobs, making HTTP requests, or interacting with other AWS services. Step Functions provides a rich set of integrations and service integrations to facilitate the execution of tasks within your workflow.

Step 5: Test and debug your workflow

Once your workflow is defined, test and validate its functionality using the Step Functions console. You can simulate and debug your workflow to identify any issues or errors. Step Functions also provides logging and monitoring capabilities to help you track the execution and performance of your workflows.

List of step function executions

image

Specific execution view

image

Here you can check on each input and output JSON, execution time, the path that you workflow took, and understand if something went wrong.


What is Amazon EventBridge Scheduler?

Amazon EventBridge Scheduler is a serverless service that allows you to schedule and automate the execution of events at regular intervals. It integrates seamlessly with other AWS services, enabling you to trigger workflows and actions based on specific schedules or time-based events. By combining EventBridge Scheduler with AWS Step Functions, you can create powerful and automated serverless workflows.

Using Amazon EventBridge Scheduler with AWS Step Functions

In my case I had to use this integration instead of simply a AWS Lambda, because my workflow had a dinamic time to wait until the execution of whole function, since a lambda function has a 15 minutes timeout, this other approach worked way better.

Here's a step-by-step process to leverage Amazon EventBridge Scheduler and AWS Step Functions for automating your serverless workflows:

Step 1: Define your event schedule

Using the EventBridge console or AWS CloudFormation, define the schedule for your event. You can choose from pre-defined intervals (e.g., every minute, hourly, daily) or create a custom schedule based on specific dates and times.

Cron expression

image

Step 2: Configure the event target

Specify the AWS Step Functions state machine as the target for your scheduled event. This ensures that the defined workflow is triggered based on the specified schedule. You can also configure additional parameters and input data to be passed to the state machine during execution.

image

Step 3: Monitor and manage your workflow

Monitor the execution and performance of your automated serverless workflow using the Step Functions console. You can view detailed execution history, track the input and output data for each state, and troubleshoot any issues that may arise.

Benefits of Automation with Step Functions and EventBridge Scheduler

Automating your serverless workflows with AWS Step Functions and Amazon EventBridge Scheduler offers several advantages:

  1. Scalability: Serverless architectures allow your workflows to scale effortlessly based on demand, ensuring that they can handle high volumes of data and traffic.
  2. Cost-effectiveness: With serverless services, you only pay for the resources consumed during execution, resulting in cost savings compared to traditional server-based approaches.
  3. Simplified orchestration: Step Functions provides a visual and intuitive interface for designing and managing complex workflows, making it easier to coordinate multiple components and services.
  4. Reliable scheduling: EventBridge Scheduler offers a highly reliable and accurate scheduling mechanism, ensuring that your workflows execute precisely according to the defined schedule.

Conclusion

Automating serverless workflows using AWS Step Functions and Amazon EventBridge Scheduler empowers developers to build efficient and scalable applications. By leveraging the visual orchestration capabilities of Step Functions and the precise scheduling of EventBridge Scheduler, you can streamline your workflows and focus on delivering value to your users.