Event-Driven Serverless Order Management System

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Overview

A fully serverless, event-driven order management system built on AWS.

This project demonstrates architectural separation, asynchronous event propagation, AI-assisted validation, and cloud-native service orchestration using managed AWS components.

The focus is not only CRUD functionality — but system design discipline and distributed flow control.

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Architecture

Conceptual Layers

Entry

• AWS Amplify (Frontend Hosting)
• Amazon API Gateway

Compute

• Independent AWS Lambda functions
• Single-responsibility execution units

Storage

• Amazon DynamoDB (Primary data store)
• Amazon S3 (Archival & reports)

Event

• Amazon SNS for asynchronous propagation

Deletion events are published to SNS and processed asynchronously by dedicated handlers, preventing tight coupling between business logic and secondary workflows.

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Intelligent Validation (Amazon Rekognition)

Image uploads are analyzed using Amazon Rekognition before order confirmation.

If the detected object does not match the provided description, a confidence-based validation warning is shown.

This integrates AI-based verification directly into a serverless backend pipeline.

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Event-Driven Deletion Flow

1. API Gateway receives delete request
2. Lambda removes record from DynamoDB
3. Lambda publishes event to SNS
4. SNS asynchronously triggers:
   • Archival Lambda → stores deleted order in S3
   • Email notifications

Core logic remains isolated and non-blocking.

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PDF Report Generation

Deleted orders stored in S3 can be aggregated into a dynamically generated PDF.

• Generated by dedicated Lambda
• Reads archival data
• Produces PDF
• Returns secure presigned URL

The reporting workflow is fully decoupled from the CRUD system.

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Lambda Structure

lambdas/
├── create_order
├── update_order
├── delete_order
├── get_orders
├── get_order_by_id
├── recognize_uploaded_image
├── on_order_deleted
├── archive_deleted_orders
├── generate_pdf_report
├── subscribe_email
└── unsubscribe_email

Each Lambda is independently deployable and responsibility-scoped.

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Engineering Principles

• Event-driven architecture
• Asynchronous SNS-based processing
• Service responsibility separation
• Stateless execution
• Managed service composition
• AI integration inside backend validation
• Secure presigned access control
• Cloud-native design patterns

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Technologies

• AWS Lambda
• Amazon API Gateway
• Amazon DynamoDB
• Amazon SNS
• Amazon S3
• Amazon Rekognition
• AWS Amplify
• Python (boto3)
• ReportLab

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Summary

This project demonstrates how distributed serverless services can be composed into a coherent, loosely coupled backend system.

It highlights architectural discipline, asynchronous processing, and AI-enhanced validation within a fully managed AWS environment.