API Creation & Management

APIs are a crucial component of SecureCart’s e-commerce platform, enabling communication between frontend applications, backend services, payment gateways, and third-party integrations. Effective API management ensures scalability, security, monitoring, and versioning while maintaining low latency and high availability.

✔ Why does SecureCart focus on API Creation & Management?

• Ensures a secure and scalable API layer for mobile and web applications.

• Facilitates integration with third-party services like payment providers and inventory systems.

• Supports API rate limiting and monitoring to prevent abuse and ensure uptime.

• Optimizes API performance using caching, throttling, and authorization mechanisms.

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🔹 Step 1: Choosing API Gateway & Backend Services

✔ What AWS services does SecureCart use to create and manage APIs?

API Type	Purpose	AWS Service Used	Use Case in SecureCart
REST API	Traditional web-based API for frontend/backend communication.	Amazon API Gateway (REST)	SecureCart’s mobile app retrieves product catalogs and order history.
GraphQL API	Allows flexible data retrieval.	AWS AppSync	SecureCart’s mobile frontend requests only the necessary fields instead of full payloads.
WebSockets API	Enables real-time two-way communication.	API Gateway (WebSocket)	SecureCart uses WebSockets for real-time inventory updates.
Private API	Restricts access to internal AWS resources.	API Gateway (Private)	SecureCart’s microservices interact securely within a VPC.

✅ Best Practices: ✔ Use REST API for public APIs exposed to external clients. ✔ Leverage GraphQL for frontend flexibility and reduced payload size. ✔ Use WebSockets for live features like cart updates and inventory tracking. ✔ Implement Private APIs for secure internal service communication.

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🔹 Step 2: Securing APIs

✔ Why? – SecureCart protects customer data, transactions, and sensitive operations through robust API security mechanisms.

Security Measure	Purpose	Use Case in SecureCart
Authentication	Ensures only authorized users access APIs.	Uses Amazon Cognito to authenticate customers and issue API tokens.
Authorization	Determines what actions users can perform.	IAM policies restrict API access based on roles (admin, customer, vendor).
Rate Limiting & Throttling	Prevents API abuse and denial-of-service attacks.	API Gateway limits requests per second for unauthenticated users.
Data Encryption	Secures sensitive API communications.	Uses TLS 1.2+ for encrypting API calls.
WAF Protection	Blocks malicious API requests.	AWS WAF protects against SQL injection and bot traffic.

✅ Best Practices: ✔ Use Amazon Cognito for API authentication with OAuth2.0. ✔ Enable API Gateway throttling and rate limits to prevent abuse. ✔ Encrypt API traffic using TLS and AWS Secrets Manager for key storage. ✔ Deploy AWS WAF for threat mitigation.

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🔹 Step 3: API Gateway Deployment & Integration

✔ Why? – API Gateway acts as a single entry point for SecureCart’s APIs, managing traffic, authentication, and integrations with backend services.

API Gateway Feature	Purpose	Use Case in SecureCart
Lambda Proxy Integration	Calls AWS Lambda for business logic.	Processes checkout transactions.
HTTP Proxy Integration	Routes requests to external APIs.	Integrates with third-party payment gateways.
VPC Link	Connects API Gateway to private resources in a VPC.	SecureCart’s order fulfillment service runs on ECS in a VPC.
Caching	Reduces redundant requests for repeated API calls.	API Gateway caches product details to improve performance.

✅ Best Practices: ✔ Use Lambda proxy integration for serverless APIs. ✔ Leverage API Gateway caching for read-heavy endpoints. ✔ Use VPC Link to securely expose private services inside a VPC. ✔ Enable request validation to reject malformed inputs before execution.

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🔹 Step 4: API Versioning & Lifecycle Management

✔ Why? – Ensures that SecureCart can introduce new API versions without breaking existing integrations.

API Versioning Approach	Purpose	Use Case in SecureCart
Path Versioning	API version included in the URL.	/v1/orders, /v2/orders for different order processing versions.
Header Versioning	API version specified in request headers.	X-API-Version: 2 allows client flexibility.
Query Parameter Versioning	API version included as a query string.	/orders?version=2 for API version switching.
Deprecation Strategy	Gracefully retire older API versions.	SecureCart supports old versions for 6 months before deprecating.

✅ Best Practices: ✔ Use path-based versioning (/v1/, /v2/) for clear API evolution. ✔ Communicate API deprecations early to allow consumers to migrate. ✔ Implement backward compatibility strategies to minimize disruptions.

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🔹 Step 5: API Observability & Performance Monitoring

✔ Why? – SecureCart needs real-time visibility into API health, latency, and failure rates to optimize performance and troubleshoot issues.

Monitoring Tool	Purpose	Use Case in SecureCart
Amazon CloudWatch Logs & Metrics	Captures API Gateway logs & error rates.	Detects latency spikes and high error rates.
AWS X-Ray	Traces API requests end-to-end.	Debugs slow API responses in microservices.
Amazon API Gateway Logging	Logs incoming API requests.	Tracks unauthorized access attempts.
AWS WAF Logs	Monitors security threats.	Detects SQL injection and bot activity on APIs.

✅ Best Practices: ✔ Enable CloudWatch monitoring for API Gateway logs and metrics. ✔ Use AWS X-Ray to trace API performance bottlenecks. ✔ Set up alarms to detect high error rates and slow responses. ✔ Monitor API Gateway latency and request volume for optimization.

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🔹 Step 6: API Cost Optimization

✔ Why? – SecureCart optimizes API Gateway and backend service costs based on traffic patterns and usage.

Optimization Strategy	Use Case in SecureCart
Use Caching	Reduces API Gateway request processing costs.
Enable Throttling	Prevents excessive usage by setting rate limits.
Choose the Right Integration	Directly integrate API Gateway with AWS services instead of using Lambda unnecessarily.
Use AWS Free Tier & Savings Plans	Optimizes costs for low-volume APIs and long-term workloads.

✅ Best Practices: ✔ Implement caching for frequently accessed endpoints. ✔ Use step-scaling for API Gateway to prevent over-provisioning. ✔ Monitor API cost breakdown using AWS Cost Explorer.

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🚀 Summary

✔ Use API Gateway with Lambda, ECS, or private endpoints for backend processing. ✔ Secure APIs with Cognito authentication, IAM authorization, and AWS WAF protection. ✔ Implement API caching, throttling, and request validation to optimize performance. ✔ Manage API versions properly to avoid breaking changes for consumers. ✔ Monitor API performance with CloudWatch, X-Ray, and WAF logs. ✔ Optimize API costs by caching and limiting unnecessary requests.

Scenario:

SecureCart is moving towards API-first development and needs to expose secure, scalable APIs to power its e-commerce mobile and web applications.

Key Learning Objectives:

✅ Learn when to use REST APIs vs. GraphQL APIs ✅ Implement Amazon API Gateway for API management ✅ Secure APIs using IAM, JWTs, and API Keys ✅ Optimize API requests using AWS Lambda & caching

Hands-on Labs:

1️⃣ Create a REST API Using Amazon API Gateway 2️⃣ Integrate API Gateway with AWS Lambda & DynamoDB 3️⃣ Implement Request Throttling and Authentication for APIs

🔹 Outcome: SecureCart builds a highly available, managed API platform.