Configuring CI/CD pipeline for AWS Lambda functions.

Jul 4, 2022 |
Views: 679 |

Reading Time:

This post is authored by Bishal Sarker, our resident Software Engineer at Astha IT.

Let’s do something cool today! We are going to create an AWS Lambda function and deploy it using CI/CD pipeline. If you have no idea about what I’m referring to, no worries. Here are some basics before you can move on:

AWS Lambda is a serverless computing service provided by Amazon Web Services. The concept of “serverless” computing refers to not needing to maintain your own servers to run these functions. Read more,

A CI/CD pipeline is a process that drives software development through a path of building, testing, and deploying code. Read more,

So, why use a pipeline if we can upload ours to Lambda manually?

We can upload it manually, that’s true. But that is only convenient when our code doesn’t need to be modified frequently and that scenario is very rare in actual software production.

Let’s begin with our code!

Okay! So firstly, let’s create a simple node.js function which will be used for sending emails. This is our send-email.js file:

const nodemailer = require(‘nodemailer’);

const sendEmail = () => {
 const smtp_config = {
   host: ‘smtp_host’,
   port: ‘smtp_port’,
   auth: {
     user: ‘smtp_auth_username’,
     pass: ‘smtp_auth_password’

 const transporter = nodemailer.createTransport(smtp_config);
   const email_request = {
     from: ‘’,
     to: ‘’,
     subject: ‘Test Email’,
     body: ‘Hi, this is a test email’

 transporter.sendMail(email_request, (error, info) => {
   if (error) {
   } else {
     console.log(“Email sent to: ” +;

module.exports = { sendEmail };

We will also need an index.js file with a handler function. It’s a Lambda convention. While triggering, Lambda will look for an index file with a handler function. Here’s is the file:

const { sendEmail } = require(‘./send-email.js’);

exports.handler = (event) => {

Now, let’s push all the codes in our repository. I’m using Bitbucket.

Configuring pipelines for the repository

After our code is pushed, we need to enable a pipeline for our repository. This step will be different for other code repository hosting platforms (GitHub, Gitlab etc.). For Bitbucket you can:

Go to Your repository Settings > Under the section of the pipeline, click on Settings > Click on the Enable Pipelines Switch to enable pipelines.

We also need to set up a few repository variables that will be required to run the pipeline:

Go to Your repository Settings > Repository variables

And set these variables as key-pair values:


Okay, now we need to add a bitbucket-pipelines.yml file which will be required by Bitbucket to trigger the pipeline. We need to create that file and push it in our repository.

     - step:
       name: Build and package
           - apt-get install -y zip
           - npm install
           - mkdir artifacts
           - cp -r ./* ./artifacts
           - cd ./artifacts
           - zip -r index.js send-email.js node_modules/
           - cd ..
           - cp -r ./artifacts/ ./
     - step:
       name: Update Lambda code
           - pipe: atlassian/aws-lambda-deploy:0.2.1
             FUNCTION_NAME: ‘sendEmailFunction’
             COMMAND: ‘update’
             ZIP_FILE: ‘’
If you want to know more about these pipeline configuration, you can check out this page:

We have set a trigger on the deployment branch. If we push any update in that branch we will be doing these two things here:

  • In step #1, we are building our application. In our case, we are resolving our npm packages. When our files are ready we are combining all these files in a compressed zip folder.
  • In step #2, we are deploying our code in lambda. In this step, pipeline will automatically authenticate by using those repository variables and upload our zipped code file to our function.

The branch name can be anything but make sure you mention that branch in bitbucket-pipelines.yml pipeline file.

Creating AWS Lambda Function

Now let’s create a lambda function. Log in to your AWS Management Console and search for Lambda. Open your Lambda dashboard and click “Create function“.

Let’s create our function sendEmailFunction from scratch, select runtime Node.js 16.x (or your preferred version) and hit “Create function“. Our function should be created and ready:

So, we are ready. Now, Let’s create a branch called “deployment” in our repository. After creating/pushing our code to deployment branch you will see that a pipeline has been started like this:

Click that running pipeline and you’ll get a view like this:

Done! Our code is successfully deployed to our sendEmailFunction. From now on, you don’t need to worry about deploying your code to Lambda function all on your own. All you have to do is to update your code and push it to your deployment branch. You can also maintain different environments with different respective branches.

Progressive Web Apps: the future of application development.

Progressive Web Apps: the future of application development.

When it comes to marketing an application, time to market and cost efficiency are two of the most important factors. Progressive Web Apps provide you with the opportunity to create user-friendly applications that are built using just HTML, CSS and JavaScript without the hassle of publishing them in an app store.

However, we do not want you to take our word for it. In this article, we are going to discuss what a competitor analysis exactly is and what questions it will help you answer, so you can make an informed decision for yourself. (Trust me though, you will not want to miss it.)

read more
The future of software development: Open Source.

The future of software development: Open Source.

Open-source software that is used by many people can be modified to suit your requirements. Businesses can save money by obtaining a product that is cost-effective, and they can work together with a community that can help them resolve any problems they encounter. Open source has many other advantages, including the fact that you can utilize something that has already been created. Our team has extensive experience in working on both big and small projects for various organizations, and we possess a lot of knowledge regarding open source.

read more
How to speed up software development with ChatGPT, GitHub Copilot, and Tabnine.

How to speed up software development with ChatGPT, GitHub Copilot, and Tabnine.

AI tools are causing a lot of arguments about what will happen to jobs, education, technology, and software development in the future. Leaders in the tech industry are thinking about the risks to security and the possibility of AI tools breaking the rules of intellectual property when used for coding help. On the other hand, people who have a lot of influence in the tech world on social media sites like Twitter and LinkedIn are talking about how AI-powered tools can make us more productive and trying to guess which jobs will go away first.

read more
The fastest way to build a multi-tenant eCommerce platform.

The fastest way to build a multi-tenant eCommerce platform.

Building a multi-tenant eCommerce platform can be an incredibly daunting task. That can be especially true if you are new to this space and exploring new technologies. Many people are busy trying to grow their businesses, but they don’t have the time to manage multiple websites. A multi-tenant eCommerce platform can help you avoid this issue while growing your business at the same time.

read more
Importance of legacy system modernization: A guide for 2023.

Importance of legacy system modernization: A guide for 2023.

Legacy system modernization is upgrading and improving the aging software systems still in use. Legacy systems are often referred to as “legacy” because they have been in use for a long time, but there are many other reasons why modernizing them is essential. Old systems can be challenging

read more