AWS Lambda with Node.js: A Quick Beginner’s Guide

Last updated on May 24th, 2023

While creating an application, every developer strives to provide consumers with an exceptional user experience. Your backend code must execute whenever an application event happens. Consequently, you must manage your infrastructure such that it can host and run backend code without difficulty. It may be accomplished by deploying and scaling servers, handling system upgrades as they become available, and constantly evaluating the infrastructure’s performance.

Developing such apps may take time and effort. But it would be fantastic if apps could be developed without any need for the underlying infrastructure. This is why AWS Lambda was designed. You will be able to create a Node.js application using AWS Lambda. Isn’t that great? And in this blog post, we will cover AWS lambda and its procedure to build the AWS Lambda with Node.js application.

A Brief Overview About AWS Lambda

With AWS Lambda, you don’t have to worry about setting up or managing servers to have your application’s or service’s code executed. You simply pay for what you need, and more than 200 AWS services and SaaS apps can communicate with Lambda.

The term “serverless” computing describes a computer model in which certain operations are not always performed by server machines. When it comes to your IT setup, look no further than AWS Lambda.

User-created “functions” are uploaded to AWS Lambda, where they are executed fast and flexibly. These functions are small, self-contained programmes that may be written in any of the supported languages and runtimes. In addition to hosting websites and handling data streams, Lambda functions may interact with APIs and link up with other AWS offerings.

AWS Lambda with Node.js Benefits

• Reduced running costs

With serverless computing, the responsibility for maintaining and operating servers is contracted out to a third party for a fee.

When you use a service that many other companies rely on, you should expect to pay less per unit. As a consequence, you’ll be able to save money on both hardware and people by reducing the amount of time spent on routine computer maintenance.

• Reduced scaling expenses

Serverless computing may be very cost-effective due to its automated horizontal scalability and its model of charging only for the resources actually used.

Picture this: your site receives its highest volume of visitors immediately following the release of your weekly marketing/sales email.

• Streamlined management of daily operations

Since the infrastructure’s auto-scaling logic is taken care of by the vendor, you need just design your application such that it can be mounted horizontally in order to take advantage of horizontal scaling.

Some of AWS Lambda’s Most Important Functions

• Controlling and Scalability

Application responsiveness and scalability in production may be fine-tuned with the help of concurrency and scaling parameters like provisioned and maximum concurrency.

• Containers

It lets you create, test, and release your Lambda functions using the resources, procedures, and dependencies of your choice, all of which are contained within the container images you already use.

• Signing Code

You can be certain that only code published by approved developers will be deployed in your Lambda services thanks to the trust and integrity restrictions provided by code signing for Lambda.

• Expansion of Lamba Extensions

Modifying your Lambda functions using an extension is possible. Extending Lambda with your favourite monitoring, observability, security, and governance tools is possible with the help of these extensions.

• Functions Map

If you’re interested in using Lambda with other AWS services or third-party apps, you can find detailed instructions and example code in a function blueprint. The blueprints provide code examples and choices for setting up functions in both the Node.js and Python programming languages.

How to Create  AWS Lambda with Node.js?

Node.js is one of the languages that the Lambda function efficiently supports. Therefore, in this part, we will develop an application with Nodejs lambda. The steps below outline how to get started using AWS Lambda with Node.js.

01. Create an AWS Account

The Lambda function implementation requires an AWS account. Create one, then. The only requirements are a valid email address, phone number, and credit card. You can utilize its free tier plan for newbies without incurring any costs. Now create a free account by following the below steps.

• Initiate the AWS console.
• Select “establish an account for free.”
• Provide every detail.
• Enter the payment information and confirm its accuracy.
• A four-digit verification code will appear on your screen. Enter it.
• Select the free plan, then.
• You are now prepared to utilize your free AWS account.

02. Configuring Your Local Development Setting

To begin development on a lambda Node.js application, we will use a serverless framework. It is a Node. Js-written CLI utility. This tool enables the rapid creation and deployment of lambda functions. Installing the serverless framework requires the installation of Node.js. However, ensure that you have the version of Node.js supported by Lambda.

Also, configure your local environment to be as similar to the production environment as possible for improved results and application work. If Node.js is not currently installed on your machine, get the most recent version. 

$ nvm install v16.15.0 

If you have another version accessible and do not wish to remove it, use the command below to switch to the above version.

$ nvm usage 16.15.0

Installing the serverless framework for your application is the next step. Execute the specified command using the -g flag, which specifies a global install.

$ npm install -g serverless

Using the following command, verify which version of the serverless framework has been installed.

$ serverless —version

03. Create an AWS Programmatic User

To utilize the lambda function for AWS Lambda with Node.js in an environment other than local, you must deploy it to the AWS environment. You will require a programmatic user account so that your Serverless framework can access and install AWS resources smoothly. This user cannot be used to access the AWS console. It will only gain access to the accessible AWS resources via API requests using access keys.

Easy methods for creating a programmatic user are outlined below.

• Enter the IAM user’s name into the search field on the AWS interface.
• Select add user 
• Enter Lambda -example-CLI as the user name, choose programmatic access and then click Next: permissions.
• To define permissions for a person, role, or group, choose the current policy directly option and check the Administrator access box.
• Click the create user button after confirming the changes.
• Select the option to download a CSV file. It will supply you with an access key ID and a secret access key.
• Now, set up the serverless CLI using the AWS credentials that were obtained.

serverless config credentials –provider aws –key <access_key_id> –secret <access_key_secret> 

04. Create Your First Lambda Application with Node.js

$ serverless create –template hello-world //lambda function nodejs 

• We’ll start by making a basic “hello world” program. Next, go on to develop a more complex program that can retrieve a picture from a URL, resize it, and then upload it to AWS’ scalable object storage service, S3.
• To get things rolling, we’ll initially use the Serverless CLI instrument to spin up our endeavor.
• The command is: $ serverless create —template hello-world.
• If the preceding command was executed properly, you should now have two files.
• To inform Serverless CLI of our preferred templates, we passed in the -template option. The Serverless CLI tool is compatible with a wide variety of pre-made templates. There is a number of templates available that are discussed below:

AWS Lambda: Handler.js, Event, Context, Callback

1. Handler.js 

This is the Lambda function containing the code below. The preceding AWS Lambda node function had three specified arguments: event, context, and a callback. Let’s examine them in depth.

‘use strict’; 

module.exports.helloWorld = (event, context, callback) => { 

… 

2. Event

It stores event information. Different events have distinct characteristics. You must specify a service to activate the Lambda function.

3. Context

It is the argument that will be passed to the Lambda function as a runtime parameter.

4. Callback

This argument returns the results to the calling party.

5. Serverless.yml

It is a file containing your API definition and any other required resources for your application to function as intended.

We will modify serverless.yml by modifying the runtime property to nodejs8.10. Then, add a new property named region to deploy your application to a particular region.

You can add the region as shown below in the serverless.yml file. 

service: serverless-hello-world 

# The `provider` block defines where your service will be deployed 

provider: 

 name: aws 

 runtime: nodejs8.10 

 region: eu-west-1 

…. 

Deploy the app 

Execute the command from your console to deploy the AWS lambda node js. 

$ serverless deploy 

You will see the below output. 

… 

api keys: 

None 

endpoints: 

GET – https://ss7n639ye3.execute-api.eu-west-1.amazonaws.com/dev/hello-world 

functions: 

helloWorld: serverless-hello-world-dev-helloWorld 

… 

In the above node lambda example, you can see the endpoint. You can open this link from your browser to see the output.

Related Article: 6 AWS Services to Consider for Your Mobile App Development Project

Do You want assistance for AWS Lambda with Node.js ?

Applications in Node.js may be quickly built with Lambda functions. Simply familiarizing yourself with Node.js and the AWS console will be enough, regardless of your level of experience. Such information is readily available on the internet. Hope this blog post of AWS Lambda with Node.js outlines a simple process for developing Lamba Node.js applications that will be helpful for you.

Serverless apps are popular now because they eliminate the need for developers to get bogged down in the nitty-gritty of setting up and maintaining servers. The only option is to hire a web development company such as iTechnolabs to get it done for you. We offer the best services to help you achieve your goals seamlessly.