Configuring CI/CD pipeline for AWS Lambda functions.

Jul 4, 2022 |
Views: 880 |

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.

The Crypto world: A simple explanation of cryptocurrencies and NFTs.

The Crypto world: A simple explanation of cryptocurrencies and NFTs.

From virtual currencies secured by cryptography to encoded digital assets representing real-world objects – the crypto world is moving fast and growing big. Some say it’s a bubble destined to get popped. Whereas some say it will change the world. What does the world of crypto hold? What is a cryptocurrency? What are NFTs? To keep up with the fast-paced world, we need answers. So let us jump in.

read more
Beyond delivery: 5 ways we go the extra mile for our clients’ success.

Beyond delivery: 5 ways we go the extra mile for our clients’ success.

In the vibrant tech tapestry of Bangladesh, Astha IT isn’t just another thread holding pixels in place. We’re the intricate patterns, the bold colors, the narrative woven into the very fabric of your digital dreams. Sure, we deliver projects on time and on budget – that’s the warp and weft of any good tech story. But what truly sets us apart is the needlepoint precision with which we go the extra mile, ensuring your success shines through every pixel. We’re not just code slingers, we’re your tech co-conspirators, your digital cheerleaders, your unwavering champions on the road to digital transformation.

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
What is DevOps and why companies should not ignore its importance?

What is DevOps and why companies should not ignore its importance?

DevOps is gaining popularity at a rapid rate in software companies around the world as it enables companies to create and improve products at a faster rate than they could with traditional approaches. DevOps includes a set of processes that lets development and operations teams work together in completing software development.

read more