Deploying a Serverless API with AWS Lambda, API Gateway, and DynamoDB

Deploying a Serverless API with AWS Lambda, API Gateway, and DynamoDB

Learn how to build and deploy a fully functional serverless API step by step

Info

Start

Index

Module 1:What is Serverless?

Module 2: Setting up AWS Lambda

Module 3: Creating API Gateway

Module 4: Storing Data in DynamoDB

Final Assessment

01

What is Serverless:?

Understanding the basics of serverless computing

What does "Serverless" Mean?

• Serverless computing allows developers to run applications without managing infrastructure.
• AWS Lambda automatically provisions compute resources when a function is triggered.
• API Gateway provides an entry point for API requests.
• DynamoDB offers a fully managed NoSQL database with automatic scaling.

• AWS Lambda: Runs your code in response to events.
• API Gateway: Acts as a bridge between users and backend services.
• DynamoDB: Stores and reterives data without managing servers

Why Use Serverless

• Scalability - Automatically adjusts to traffic.
• Cost Efficiency - Pay only for what you use.
• Reduced Maintenance - no need to manage infrastructure
• Event-Driven - Functions execute only when needed

Serverless vs. Traditional Hosting

Question

When is Serverless a Good Choice?

• Web APIs - Handle thousands of requests per second.
• Data Processing - Process logs, IoT data, event-driven workloads.
• Scheduled Tasks - Automate database cleanups, email notifications.

'We believe that microservices and serverless functions will form the fabric of intelligent applications of the future'

01

Module Complete!

You now understand what Serverless Computing is! Next, we'll deploy your first AWS Lambda function

02

Setting Up AWS Lamba

Creating Your First Serverless Function

What is AWS Lambda?

AWS Lambda is a serverless compute service that lets you run code without provisioning or managing servers. It automatically scales your applications by running code in response to each trigger.​ Key Features:

• Event-Driven: Executes code in response to triggers such as changes in data or system state.​
• Scalable: Automatically adjusts the execution capacity based on the volume of incoming requests.​
• Cost-Efficient: With AWS Lambda, you pay only for the compute time you consume—there's no charge when your code isn't running.

Creating Your First Lambda Function

Step 1: Access the AWS Lambda Console- Log into your AWS account and navigate to the Lambda service.Step 2: Create a New Function- Click "Create function". - Select "Author from scratch". - Enter a Function name (e.g., myFirstLambda). - Choose a Runtime (e.g., Node.js or Python) - Click "Create function"Step 3: Write the Function Code- (May already exist as boilerplate) - In the Code source, write or paste your code. - For example, a Node.js function:

Testing and Monitoring

Step 1: Create a Test Event- Click "Test" in the Lambda Console. - Configure a new test event with default settings. - Click "Create".Step 2: Invoke the Function- Click "Test" to run the function. - Check the Execution result for the output.Step 3: View Logs- Select "Monitor" in the Lambda Console- Navigate to Amazon CloudWatch Logs to monitor function logs.

Example Test

Best Practices and Resources

Best Practices:

• Modularize Code: Keep functions focused on single tasks.​
• Handle Exceptions: Implement error handling to manage failures gracefully.​
• Optimize Performance: Monitor and adjust memory and timeout settings as needed.

02

Module Complete!

Now you know how to deploy a basic lambda function! Next, we'll look at creating an API Gateway

02

Module Complete!

Now you know how to deploy a basic lambda function! Next, we'll look at creating an API Gateway

03

Creating API Gateway

Exposing Your Lambda Function as a REST API

What is AWS API Gateway?

AWS API Gateway is a fully managed service that enables developers to create, publish, secure, and monitor APIs at scale. It acts as a gateway for applications to access data and services through AWS Lambda, DynamoDB, and other AWS services. Key Features:

• Fully Managed – No need to manage infrastructure
• Scalable – Handles high traffic efficiently
• Secure – Provides authentication, authorization, and rate limiting

Creating an API in API Gateway

Step 1: Access the API Gateway Console - Log in to AWS and navigate to API Gateway.Step 2: Create a New API - Click "Create API" → Select "REST API" → Click "Build".- Enter a name (e.g., MyServerlessAPI) and description (optional). - Click "Create API".Step 3: Create a Resource - Under Resources, click "Create resource".- Enter a resource name (e.g, messages) and click "Create Resource"

Connecting API Gateway to AWS Lambda

Step 1: Create a Method- Under "Methods" select "Create Method". - Choose "GET" from the Method Type dropdown.Step 2: Integrate with AWS Lambda- Under "Integration Type" select "Lambda Function". - Select "Use Lambda Proxy integration". - Enter the Lambda function name (myFirstLambda) - Click "Create method"

Deploying and Testing Your API

Step 1: Deploy the API- Click "Deploy API" - Select *New Stage* → Enter a stage name (e.g., dev) - Click "Deploy"Step 2: Note the Invoke URL- After deployment, copy the Invoke URL provided (e.g., https://xyz123.execute-api.us-east- 1.amazonaws.com/dev/messages).

03

Module Complete

Now onto DynamoDB!

04

Storing Data in DynamoDB

Using AWS DynamoDB to Store and Retrieve API Data

What is DynamoDB

AWS DynamoDB is a fully managed NoSQL database serivce that provides fast, scalable, and serverless storage for applications.

• Key Features:
• Fully Managed - AWS handles infrastructure, scaling, and availability.
• Fast Performance - Millisecond response times.
• Scalable - Automatically scales based on demand.

Creating a DynamoDB Table

• Step 1: Access the AWS DynamoDB Console
• Log into AWS Managerment Console → Open DynamoDB.
• Step 2: Create a New Table
• Click "Create Table".
• Set the Table Name as "MessagesTable"
• Set the Primary Key:
• Partition Key: id (Type: String)
• Step 3: Configure Settings
• Leave Provisioned Capacity set to On-Demand Mode (default)
• Click Create Table

Video Guide:

Modifying the Lambda Function to Store Data

Step 1: Add AWS SDK for DynamoDB In your Lambda Function, include the AWS SDK for DynamoDB:

Step 2: Modify the Function to Store Data Replace the existing Lambda function code with the following:

Retrieving Data from DynamoDB

Step 1: Modify the Lambda Function to Retrieve Data Update the Lambda function to fetch data by ID:

Deploying and Testing the Integration

• Step 1: Deploy the Updated Lambda Function
• Click"Deploy" in the AWS Lambda console.
• Step 2: Invoke the Function via API Gateway
• Send a POST request to your API gateway invoke URL:
• curl -X POST https://xyz123.execute-api.us-east-1.amazonaws.com/prod/messages
• Step 3: Verify Data in DynamoDB
• Open DynamoDB Console → Select MessagesTable → Click Explore Table
• You should see a new record with id = 123

04

Module Complete

You've Successfuly Stored and Retrieved API Data using AWS DynamoDB!

05

Final Testing and Best Practices

Ensuring a Fully Functional and Secure Serverless API

Testing the Full API Workflow

I’m an awesome subtitle, ideal for giving more context about the topic at hand

Step 1: Sending a POST Request to Store Data

Step 2: Checking DynamoDB for Stored Data

Step 3: Sending a GET Request to Retrieve Data

Optn Terminal and Postman and run: "curl -X POST https://xyz123.execute-api.us-east-1.amazonaws.com/prod/messages " Expected Response: "Success": True

1.Open AWS DynamoDB Console 2. Select MessagesTable - Click Explore Table 3. Verify that a new entry exists with id = 123

Optn Terminal and Postman and run: curl -X GET https://xyz123.execute-api.us-east-1.amazonaws.com/prod/messages Expected Response: "id": "123", "message": "Hello, DynamoDB!"

Optimizing API Performance

Optimize Lambda Memory & TImeout Adjust settings for faster execution

Use API Gateway Caching Store reponses to reduce calls to Lambda

Use AWS CloudWatch Monitor logs and error rates

Security Best Practices

Enable IAM Authorization - Restrict access to AWS resources. Use API Gateway Authentication - Secure endpoints with IAM, API Keys, or JWT tokens. Validate Input Data - Prevent injection attacks by sanatizing API inputs.

05

Section Complete!

Now for the Final Assessment

If any you feel need to be marked false proceed back to that section and review again

Final Assessment and Completion

Welcome!

In this module, you'll learn how ot deploy a serverless API using AWS Lambda, API Gateway, and DynamoDB

What you'll learn:

• What is serverless?
• How AWS Lambda, API Gateway, and DynamoDB work together
• Deploying a working API using Terraform
• Testing and debugging your serverless API