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What Is Lambda AWS?

Posted on October 26, 2022 by

Categories: AWS


Although AWS has helped Lambda gain popularity recently, many people still confuse the terms with serverless. In this article, we’ll explain AWS Lambda in more detail, including its relationship to serverless architecture and its creation and application.

(This lesson is included in our AWS Guide. To browse, use the menu on your right.)

recognizing serverless

We must first comprehend serverless architecture to grasp what AWS Lambda is. Apps that don’t require server deployment are known as serverless applications. You have the advantage of not having to worry about OS setup, server patching, or server scaling when you operate a serverless application as opposed to a physical server.

There are four qualities of serverless platforms or applications:

  1. No server administration
  2. Adaptable sizing
  3. no unused capacity
  4. a lot of availability

There are several levels and components in serverless applications:

  • Compute
  • API
  • Storage
  • Interprocess Communication
  • Orchestration

Each of these elements of a serverless architecture may be implemented using the services that cloud provider AWS provides. Herein lies the role of AWS Lambda.

How to describe AWS Lambda

The high-scale, provision-free serverless computing solution AWS Lambda offers is built on functions. It is exclusively employed in serverless applications’ computation layer. Building event-driven apps that may be triggered by various AWS events is the goal of AWS Lambda.

Lambda just spins up several copies of the function to handle the events when there are several simultaneous occurrences. To put it another way, Lambda is a function as a service (FaaS). AWS Lambda is composed of three elements:

  • A purpose. The work is really carried out by this code.
  • An arrangement. This outlines the execution of your function.
  • An occasion source (optional). This is the circumstance that starts the function. Several AWS services or a third-party service can be used to trigger.

Your function is called whenever an event from the source you provide an event source for happens. The illustration below illustrates how this appears:

Execution of a Lambda function

Which runtime environment you want to use to execute your code is something you select when setting a lambda function. Each environment offers its own binaries that you may utilize in your code depending on your chosen language. Additionally, provided you can utilize the libraries or binaries in the runtime environment, you are free to package whatever libraries or binaries you like. Every environment is built using the Amazon Linux AMI.

The runtime environments that are currently accessible are:

  • nodeJS
  • Python
  • Go
  • Java
  • Ruby
  • .Net
  • C#

We solely concentrate on the code while executing a lambda function because AWS handles capacity and all updates. Both the ResponseRequest InvocationType and the EventInvocationType may be used to execute AWS Lambda synchronously.

Understanding the Lambda function

There are essential principles to comprehend how a lambda function functions.

incident source

Although the Invoke API may be used to activate AWS Lambda, event sources within AWS are the preferred method.

Two invocation models are supported:

  • Push is activated by additional events like API gateway, a newly created item in S3, or Amazon Alexa.
  • Pull the lambda function’s output and poll an event source for newly created objects. DynamoDB or Amazon Kinesis are two examples of such event sources.

Configuration in lambda

Few setup options are available for lambda functions:

  • The memory dial, which also influences the amount of CPU and network resources allotted to the function, regulates both.
  • To restore functionality to earlier versions, version/aliases are employed. Using a deployment strategy like blue/green or isolating the production environment from lesser environments is also crucial.
  • The lambda function may communicate with other AWS services and APIs thanks to the IAM Role.
  • Which push model event source is permitted to call a lambda function is determined by the lambda function authorization.
  • Setting up the network for connectivity outside. The options are two:
  • Internet access is enabled by default. However, private resources in your VPC services are not accessible.
  • VPC enables the provisioning of your function inside your VPC and using an ENI. Following that, you may attach elements like security as you would with any other ENI.
  • Environment variables for injecting values that are used by code dynamically. One of the 12 factors of the 12-factor app technique for cloud-native applications is the notion of isolating code from the configuration.
  • You should send all unsuccessful invocation events to the dead letter queue. Either SNS or SQS may be used for this.
  • Timeouts are the maximum time a function can execute before timing out.

AWS Lambda creation

The most popular approach to constructing a lambda function in AWS is through the console, although this technique should only be used while testing in development. The deployment of Lambda should be automated for production.

A few third-party tools are available for setting up automation, such as Terraform. Still, because we are discussing an AWS service, in particular, AWS suggests utilizing Serverless Application Model (SAM). Except for a transform block that clearly states that we want the template to be a SAM template rather than a conventional CloudFormation template, SAM is essentially built on top of AWS CloudFormation. In the AWSlabs, you may look at a few sample templates.