AWS Step Function 👣

Hey Cloud people☁. In this article I’ll cover one of the most used AWS service i.e. AWS Step Function in brief. For the ease of understanding the article will be divided into 5 major parts — What, Why, Who, Use-Cases & Disadvantages. So let’s dive into it 😼

WHAT is AWS Step Function?
AWS Step Functions is a visual workflow service that helps users to -
- Manage Workflow/Orchestration Service with Centralized State.
- Create Visually using the workflow studio or via IaC.
- Use flow constructs to control the behavior of their workflow.
- Use 200+ AWS service integrations to perform tasks.
- Build distributed & reliable systems.
- Setup comprehensive monitoring & debugging tools.

WHY is it used?
It is used for many purposes but some of it’s main usages are:
- Simplifying implementation by writing workflows instead of code.
- You can just drag and drop and create the workflow easily.
- Easy to understand when shifting contexts.
- Build faster using the workflow studio.
- Easy integration with other AWS services.
- Completely Serverless ( no infrastructure to manage ).
- Built in resiliency features like error handling and retry logic.
- Monitoring & Debugging features help track state and diagnose problems.

You can make workflow using flows constructs like Chaining, Choice state (If/Else), Human Interaction, Parallelism and more.

Here is a simple Step Function for you to understand how this service works —

So, in this workflow we are using Lambda and SNS service with Step Function to perform a task named “apply for approval” in SNS service.
1. After the start we are using Choice state flow (if/else) to check if the customer already exists or not.
2. The default return value is Yes, and then the SNS function is directly executed and the workflow will end.
3. If return value of choice state is No, it’ll invoke the Lambda function to create the customer.
4. After the customer is created it will then check the eligibility of the customer (if it exists or not).
5. And lastly it’ll send it to SNS to perform the defined function.

USE-CASES —
- Micro-service Coordination
- Serverlesspresso ( check it out on Youtube )
- Large Scale processing
- ML model training

WHO USES IT?
Here are some big MNCs that use Step Function for building efficient workflows:
- Coinbase
- Yelp
- Thomson Reuters
- CocaCola
- And ofcourse, Amazon

DISADVANTAGES
I know I’ve only talked about the good things only about this service, so here some disadvantages as well:
- Learning overhead: To build good workflows with integrated services, one has to learn about the Step Function and creation of workflows.
- Costly: It can cost a lot to build a step function as it comes under one of the most expensive services offered by AWS.
Centralized state: The Step Function is not good for large working environments as the workflow is in centralized state, and in large environment it can be very difficult if a certain department needs to any changes in the workflow.

Now, we’ve covered the basic details about the AWS Step Function and I feel that you’ve got an idea about it. So to follow up and learn more about the Step Function I would suggest you to watch this Serverlesspresso Re:invent video by AWS. Serverlesspresso is a pop-up coffee shop that provides premium espresso drinks which is totally build using AWS services, mainly Step Function :)

You made it till the end! 🎉 Thank you for reading the whole article and I hope you liked the article and find it meaningful. Please provide any improvement/feedback in the comment section.
Connect with me here: Pawan Gambhir