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AWS Step Functions 101

We are going to talk about an essential part of AWS Lambda called “AWS Step Functions.” What are Step Functions? Why are they important for AWS Lambda users? What are they used for, and what can we expect to get by using them? Bare with us, and discover more critical information on Step Functions throughout this article.

The Beginning

We’ll begin with the explanation of what are Step Functions. AWS Step Functions service is the most recent service released by none other than Amazon Web Services. The primary goal of Step Functions is to solve the problems that arise by the orchestration of complex flows via Lambda functions.

In most cases, there are several processes made out of different tasks. To be able to run the whole process serverless, you need to create Lambda function for every task, and after you’ve created them, you need to run them via your orchestrator.

You need to write a code that will orchestrate these functions, and successfully writing code like that is not an easy task at all because of optimization and debugging of this code.

With Step Functions you’ll be able to orchestrate complex designs with simple flows.

AWS Step Functions service will make your life easier by removing the need for all this with its simple design, and it’ll also implement a complex flow for our tasks or functions.

In short, AWS Step Functions will make it easy to manage and coordinate the distributed application’s components along with microservices all thanks to the utilization of the visual workflow.

Why Should You Use Orchestration For Your Application Design?

Consider this - breaking your application into many pieces (service components) allows your system to keep on going even though a single element has failed. Each of these components can scale independently, and there’s no need to redeploy the entire system after every change because every component can be updated on its own.

Scheduling, managing execution dependencies, and concurrency within the logical flow of the application are all involved in the coordination of service components. In applications like this, the developers are able to use service orchestration to handle failures as well.

How Does Step Functions Work?

By using Step Functions, you’re actually defining state machines that describe your workflow as a series of steps, their relationship as well as their outputs and inputs. State machines consist of a number of states, and every state represents an individual step of a workflow diagram. States can pass parameters, make choices, perform work, manage timeouts, terminate your workflow with success or failure, and initiate parallel execution as well. The visual console will automatically graph every state following the execution order.

All of the above makes it very easy to design multi-step apps because the console highlights the status of each step in real-time, and it provides a history of every execution in details.

Connecting Step Function To Other AWS Services

By utilizing service tasks, you can connect and coordinate the workflow you’ve created via Step Functions with other AWS services. What else can you do? Here are some of the examples:

  • You can run Amazon Fargate task or Amazon ECS;
  • You can submit an AWS batch job, but you need to wait for it to complete;
  • You’re able to publish a message on SNS Topic;
  • You can create an Amazon SageMaker job which can train a machine learning model;
  • You can invoke AWS Lambda function;
  • You can send a message to Amazon SQS queue;
  • You can also place a new item in the DynamoDB table or obtain an existing item from the DynamoDB table.

Step Functions - Monitoring & Logging

How does the monitoring work with Step Functions? Step Functions will send metrics to AWS CloudTrail and Amazon CloudWatch to monitor applications. CloudTrail will capture all API calls for Step Functions as events, while the calls from Step Functions and from code calls are all included to the Step Functions APIs.

CloudWatch can set alarms, collect and track all the track metrics, and it will automatically react to any changes that occur in Step Functions. Step Functions support CloudWatch Events’ managed rules for every integrated service inside your workflow. Step Functions will create and manage CloudWatch Events rules within your Amazon Web Services account.

The Most Frequent Step Functions’ Use Cases

You can use Step Functions to create an end-to-end workflow which will allow you to manage jobs with interdependencies. The whole idea of Step Functions is to help you solve any business process or computational problem which can be divided into a series of steps. Here are some of the examples:

  • Implement a difficult sign-on authentication and user registration processes for web applications;
  • Creating event-driven apps that can automatically respond to infrastructure changes and building tools for constant deployment and integration. These are crucial for IT automation and DevOps;
  • Processing of data: Unified reports are made by consolidating data from multiple databases. It can reduce and refine large data sets into a more comfortable file format, or even coordinate machine learning workflow and multi-step analytics.

Let’s wrap it up

Primarily, Step Functions can help us achieve higher performance rates by allowing us to break down our application into service components and manipulate them all independently.

Amazon Step Function service is relatively new, and like everything else from AWS, it’ll only get better as time goes by, and it’ll surely become more useful. Discover Step Functions service for yourself, and give us some feedback.

In case you liked this article, take a look at our blog for more. If you have experience with AWS Step Functions, share it with our readers and us in the comment section underneath this article, and feel free to start a discussion.

Our team at Dashbird encourages you to share all your thoughts about this topic and see what others think of Step Functions service and how it can affect our everyday lives.

A compilation of lessons learned at Dashbird after working with 4,000+ customers and 300,000+ Lambda functions

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