🚀 Text Processing Serverless API

A fully serverless CRUD API built using AWS Lambda, API Gateway, and DynamoDB.
Designed with clean architecture, structured logging and production‑grade error handling.

---

📑 Table of Contents

• 📸 Screenshots
• 🏗 Architecture Overview
  • High‑Level Architecture Diagram
  • Sequence Diagram (POST → DynamoDB)
• 🌐 Base URL
• 📚 API Documentation
  • POST /
  • GET /results
  • GET /results/{id}
  • DELETE /results/{id}
  • CORS
  • DynamoDB Schema
  • Logging Strategy
  • Local Testing
• 🚧 Future Improvements
• 🎉 Final Notes

📸 Screenshots

01 — API Gateway Routes

02 — DynamoDB Table

03 — CloudWatch Logs

04 — cURL Tests (POST → GET All → GET One → DELETE)

---

🏗 Architecture Overview

High‑Level Architecture Diagram

                ┌──────────────────────────┐
                │      API Gateway         │
                │  (REST Endpoints Layer)  │
                └─────────────┬────────────┘
                              │
     ┌────────────────────────┼────────────────────────┐
     │                        │                        │
┌──────────┐           ┌──────────────┐         ┌──────────────┐
│ POST /   │           │ GET /results │         │ GET /results/ │
│process   │           │   (list)     │         │     {id}      │
└────┬─────┘           └──────┬───────┘         └──────┬───────┘
     │                        │                        │
     ▼                        ▼                        ▼
┌──────────┐           ┌──────────────┐         ┌──────────────┐
│ Lambda   │           │ Lambda       │         │ Lambda       │
│Process   │           │ListResults   │         │GetResult     │
└────┬─────┘           └──────┬───────┘         └──────┬───────┘
     │                        │                        │
     └──────────────┬─────────┴──────────┬────────────┘
                    ▼                    ▼
                ┌──────────────────────────────┐
                │     DynamoDB Table           │
                │  TextProcessingResults       │
                └──────────────────────────────┘

Sequence Diagram (POST → DynamoDB)

Client
  │
  │ POST /
  ▼
API Gateway
  │
  │ invokes Lambda
  ▼
ProcessTextFunction
  │
  │ put_item()
  ▼
DynamoDB
  │
  │ success
  ▼
ProcessTextFunction
  │
  │ returns JSON
  ▼
Client

🌐 Base URL

https://3ki380u3fc.execute-api.eu-north-1.amazonaws.com

📚 API Documentation

🔵 POST /

Process text and store the result.

Request Body

{
  "text": "hello world"
}

Example Response

{
  "id": "uuid",
  "original": "hello world",
  "uppercase": "HELLO WORLD",
  "length": 11,
  "timestamp": 1771283745
}

Example cURL

curl -X POST https://3ki380u3fc.execute-api.eu-north-1.amazonaws.com/ \
  -H "Content-Type: application/json" \
  -d '{"text": "hello world"}'

---

🟢 GET /results

List all stored results.

Example Response

[
  {
    "id": "uuid",
    "original": "hello",
    "uppercase": "HELLO",
    "length": 5,
    "timestamp": 1771283745
  }
]

Example cURL

curl https://3ki380u3fc.execute-api.eu-north-1.amazonaws.com/results

---

🟡 GET /results/{id}

Retrieve a single result by ID.

Example Request

GET /results/f5e565d8-bc1f-4911-a810-e1c3e06d8c98

Example Response

{
  "id": "f5e565d8-bc1f-4911-a810-e1c3e06d8c98",
  "original": "hello",
  "uppercase": "HELLO",
  "length": 5,
  "timestamp": 1771283745
}

Example cURL

curl https://3ki380u3fc.execute-api.eu-north-1.amazonaws.com/results/<id>

---

🔴 DELETE /results/{id}

Delete a result by ID.

Example Request

DELETE /results/f5e565d8-bc1f-4911-a810-e1c3e06d8c98

Example Response

{ "message": "Item deleted successfully" }

Example cURL

curl -X DELETE https://3ki380u3fc.execute-api.eu-north-1.amazonaws.com/results/<id>

---

🛡 CORS

All responses include:

{
  "Access-Control-Allow-Origin": "*",
  "Access-Control-Allow-Methods": "GET,POST,DELETE,OPTIONS",
  "Access-Control-Allow-Headers": "Content-Type"
}

---

🗄 DynamoDB Schema

Table: TextProcessingResults

Attribute   | Type
------------|--------
id          | String (PK)
original    | String
uppercase   | String
length      | Number
timestamp   | Number

---

📊 Logging Strategy

Every Lambda uses structured JSON logs:

{
  "level": "INFO",
  "message": "Item stored successfully",
  "requestId": "abc-123",
  "details": { "id": "uuid" }
}

This makes CloudWatch logs:

• searchable
• filterable
• machine‑readable
• consistent across all Lambdas

---

🧪 Local Testing

POST

curl -X POST https://3ki380u3fc.execute-api.eu-north-1.amazonaws.com/ \
  -H "Content-Type: application/json" \
  -d '{"text": "hello"}'

GET all

curl https://3ki380u3fc.execute-api.eu-north-1.amazonaws.com/results

GET one

curl https://3ki380u3fc.execute-api.eu-north-1.amazonaws.com/results/<id>

DELETE

curl -X DELETE https://3ki380u3fc.execute-api.eu-north-1.amazonaws.com/results/<id>

🚧 Future Improvements

Planned enhancements for the next iteration:

• Add authentication (Cognito or JWT-based access control)
• Add pagination support to /results
• Add an update endpoint (PATCH)
• Build a frontend UI (React or Svelte)
• Add full infrastructure-as-code deployment (CloudFormation or CDK)

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🎉 Final Notes

This project demonstrates:

• Clean serverless architecture
• Modular Lambda design
• Consistent structured logging
• DynamoDB best practices
• Production‑grade error handling

A solid showcase of DevOps and backend engineering skills.