AWS Lambda is a serverless computing service that lets you run code without provisioning or managing servers. It is a highly scalable and cost-effective solution for running functions in response to events.
With AWS Lambda, you can design and build applications that are event-driven, and can run and scale automatically.Design patterns are a way to capture proven solutions to common problems and make them reusable.
They provide a starting point for creating scalable, maintainable and robust applications. In this post, we will discuss some of the most common design patterns for AWS Lambda.
Simple Event Processing:
This design pattern is the simplest way to process events with AWS Lambda. The Lambda function is triggered by a specific event, such as an Amazon S3 object upload or an Amazon SNS message, and performs a specific action, such as processing the uploaded object or sending the SNS message to a different service.
Fan-Out is a design pattern that allows you to process events concurrently. It is used when you have multiple independent tasks that can run in parallel, such as sending emails, updating databases, and generating reports. With Fan-Out, you can divide the work into multiple Lambda functions, which are triggered by the same event and run in parallel.
Fan-In is a design pattern that allows you to process the results of multiple events. It is used when you have multiple Lambda functions that perform independent tasks and you want to aggregate the results. With Fan-In, you can use Amazon SNS, Amazon SQS, or other AWS services to collect and aggregate the results, and then process them in another Lambda function.
This design pattern allows you to run long-running tasks in the background and respond to events as soon as they occur. With Asynchronous Workflows, you can use AWS Step Functions to build, visualize, and run workflows, and coordinate the steps of your application. You can also use Amazon SNS or Amazon SQS to manage the execution of Lambda functions and to monitor the progress of your workflows.
Event Sourcing is a design pattern that allows you to store the complete history of events for an application in a durable and easily accessible manner. With Event Sourcing, you can use Amazon DynamoDB to store the events, and you can use Lambda functions to process the events and update the state of your application.
Command Query Responsibility Segregation (CQRS):
CQRS is a design pattern that separates the responsibilities of reading and writing data. With CQRS, you can use Lambda functions to handle different types of requests, such as commands to change data and queries to read data. This design pattern allows you to optimize the performance of your application and to separate the concerns of the different parts of your application.
In conclusion, these are some of the most common design patterns for AWS Lambda. Each pattern has its own benefits and limitations, and you can choose the right one for your needs based on the requirements of your application. By using these design patterns, you can create scalable, maintainable, and robust applications that run on AWS Lambda.