Dynamo CRUD API

A fully serverless REST API built on AWS Lambda and DynamoDB, deployed automatically via GitHub Actions. Supports complete Create, Read, Update, and Delete operations for posts.

Tech Stack

Layer	Technology
Runtime	Node.js 20.x
Compute	AWS Lambda
Database	AWS DynamoDB
API Gateway	AWS API Gateway (HTTP)
IaC	Serverless Framework
CI/CD	GitHub Actions
Notifications	Slack Webhooks

Architecture

Client → API Gateway → Lambda Functions → DynamoDB
                            ↓
                     GitHub Actions (CI/CD)
                            ↓
                     Slack (Notifications)

Each Lambda function is assigned its own minimal IAM role (principle of least privilege).

API Endpoints

Method	Endpoint	Description
GET	/posts	Retrieve all posts
GET	/post/{postId}	Retrieve a single post by ID
POST	/post	Create a new post
PUT	/post/{postId}	Update an existing post
DELETE	/post/{postId}	Delete a post

All endpoints return JSON and have CORS enabled.

Response Format

{
  "message": "descriptive message",
  "data": {}
}

Project Structure

dynamo-crud-api/
├── .github/
│   └── workflows/
│       └── main.yml        # CI/CD pipeline
├── api.js                  # Lambda handler functions
├── db.js                   # DynamoDB client initialization
├── serverless.yml          # Serverless Framework config (infra + routes)
└── package.json

Getting Started

Prerequisites

• Node.js 20+
• Serverless Framework CLI
• AWS account with appropriate permissions

Install Dependencies

npm install

Deploy Manually

npm install -g serverless

export AWS_ACCESS_KEY_ID=your_access_key
export AWS_SECRET_ACCESS_KEY=your_secret_key

serverless deploy --stage dev --region us-east-1

CI/CD Pipeline

Every push to main triggers an automated GitHub Actions workflow:

1. Checkout code
2. Set up Node.js 20 with npm caching
3. Install dependencies (npm ci)
4. Deploy via Serverless Framework
5. Send a Slack notification (success or failure) with commit info, actor, and deployment duration

Required GitHub Secrets

Secret	Description
AWS_ACCESS_KEY_ID	AWS IAM access key
AWS_SECRET_ACCESS_KEY	AWS IAM secret key
SLACK_WEBHOOK_URL	Incoming webhook URL for Slack notifications

Infrastructure Details

• DynamoDB Table: Configured via serverless.yml
• Primary Key: postId (String)
• Billing: On-demand (pay-per-request)
• Lambda Memory: 128 MB
• Lambda Timeout: 10 seconds
• Region: Configured via serverless.yml