Re-Architecting the Web Application Stack on AWS (PaaS & SaaS)

This project implements a flexible, scalable, and automated web application stack using AWS services. The architecture leverages Platform-as-a-Service (PaaS) and Software-as-a-Service (SaaS) to simplify deployment and reduce operational overhead. Below is the step-by-step guide to setting up the infrastructure and deploying the application.

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Flow of Execution

1. Login to AWS Account

• Sign in to your AWS Management Console with appropriate permissions to create resources.

2. Create a Key Pair for Beanstalk Instances

• Navigate to the EC2 Dashboard → Key Pairs.
• Create a new key pair and download the .pem file for SSH access to instances managed by Elastic Beanstalk.

3. Create Security Groups for Backend Services

• Define a Security Group (SG) for backend services (Amazon RDS, Amazon ElastiCache, Amazon MQ).
• Allow internal traffic and specific ports (e.g., MySQL: 3306, ElastiCache: 11211, MQ: 5672) for communication.

4. Create Backend Services

• Amazon RDS:
  • Choose a database engine (e.g., MySQL).
  • Configure the DB instance with appropriate storage and networking.
• Amazon ElastiCache:
  • Deploy a Memcached or Redis cluster for caching.
• Amazon MQ:
  • Set up an ActiveMQ broker for message queuing.

5. Create an Elastic Beanstalk Environment

• Use the Elastic Beanstalk Console to create a new application.
• Configure it with the desired platform (e.g., Tomcat for Java apps).

6. Update Backend Security Group Rules

• Add a rule to the backend SG to allow traffic from the Beanstalk SG.
• Allow internal communication within the backend SG.

7. Launch an EC2 Instance for MySQL Access

• Create an EC2 instance for accessing the RDS database.
• SSH into the instance and initialize the database schema on the RDS instance.

8. Update Beanstalk Health Check

• Change the health check endpoint of the Beanstalk environment to /login to match your application logic.

9. Add HTTPS Listener to Load Balancer

• In the Elastic Beanstalk console, configure the environment’s load balancer to include a 443 HTTPS listener.
• Use AWS Certificate Manager (ACM) to create an SSL certificate and attach it to the load balancer.

10. Build Artifact from Source Code

• Build the application artifact (e.g., a WAR or JAR file) locally or via a CI/CD pipeline.
• Ensure the backend service configurations (e.g., database URL, credentials) are included.

11. Deploy Artifact to Elastic Beanstalk

• Use the Beanstalk console or AWS CLI to deploy the built artifact to the environment.

12. Create Content Delivery Network with CloudFront

• Set up an Amazon CloudFront Distribution with your application as the origin.
• Use an SSL certificate for HTTPS connections.

13. Update Load Balancer Endpoint in GoDaddy

• Log in to your GoDaddy account.
• Update the domain’s DNS settings to point to the CloudFront distribution or load balancer endpoint.

14. Validate and Test

• Access your application using the URL (with HTTPS).
• Verify the functionality, performance, and scaling of your stack.

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Architecture Overview

The web application stack is built with the following components:

1. Elastic Beanstalk: Manages the application stack with auto-scaling and load balancing.
2. Amazon RDS: Provides a managed relational database.
3. Amazon ElastiCache: Speeds up application performance with caching.
4. Amazon MQ: Ensures reliable messaging with a managed ActiveMQ broker.
5. Amazon CloudFront: Delivers content globally with low latency and SSL encryption.
6. AWS Certificate Manager: Secures the application with HTTPS.

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Benefits of this Approach

• Flexible Infrastructure: Easily scales with demand.
• Automation: Simplified provisioning and deployment using Elastic Beanstalk.
• Cost Efficiency: Operates on a pay-as-you-go model with no upfront investment.
• Performance & Reliability: High availability and global reach through managed AWS services.
• Business Agility: Enables quick updates, feature additions, and scaling.

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Prerequisites

• AWS Account with necessary permissions.
• Access to application source code and build tools.
• A registered domain (e.g., GoDaddy).

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Useful Commands

AWS CLI Commands

• Deploy application to Elastic Beanstalk:

  aws elasticbeanstalk create-application-version --application-name <AppName> --version-label <Version> --source-bundle S3Bucket=<Bucket>,S3Key=<Key>
  aws elasticbeanstalk update-environment --application-name <AppName> --environment-name <EnvName> --version-label <Version>