Tools for API Gateway - Kong, NGINX, and AWS API Gateway

In the world of microservices, API Gateways are essential tools for managing client interactions, ensuring security, and improving performance. Among the many available tools, Kong, NGINX, and AWS API Gateway stand out as popular choices. This tutorial explores each of these tools in detail, covering their setup, features, advantages, and use cases.

1. Kong API Gateway

Kong is an open-source API Gateway built on top of NGINX. It provides scalability, low latency, and a rich ecosystem of plugins for authentication, rate limiting, logging, and more.

Key Features of Kong

1. Plugin Architecture
   • Kong’s plugin architecture allows users to extend its functionality with built-in or custom plugins.
   • Common plugins include authentication (OAuth2, JWT), rate limiting, and logging.
2. High Performance
   • Kong is built on NGINX and written in Lua, ensuring low-latency request handling.
3. Clustering
   • Kong supports clustering, which distributes incoming traffic among multiple instances, enhancing reliability and fault tolerance.

How Kong Works

Kong operates as a reverse proxy. It routes client requests to the correct backend service, applying any configured plugins along the way.

Setting Up Kong

1. Install Kong
   • Install Kong using Docker or the binary package for your operating system. Using Docker:

   docker run -d --name kong \
     -e "KONG_DATABASE=off" \
     -e "KONG_PROXY_ACCESS_LOG=/dev/stdout" \
     -e "KONG_ADMIN_ACCESS_LOG=/dev/stdout" \
     -e "KONG_PROXY_ERROR_LOG=/dev/stderr" \
     -e "KONG_ADMIN_ERROR_LOG=/dev/stderr" \
     -e "KONG_ADMIN_LISTEN=0.0.0.0:8001" \
     -p 8000:8000 \
     -p 8001:8001 \
     kong

2. Add a Service
   • Define a backend service to route requests to:

   curl -i -X POST http://localhost:8001/services \
     --data 'name=user-service' \
     --data 'url=http://localhost:8080'

3. Add a Route
   • Create a route for the service:

   curl -i -X POST http://localhost:8001/services/user-service/routes \
     --data 'paths[]=/api/users'

4. Enable Plugins
   • Enable plugins like rate limiting:

   curl -i -X POST http://localhost:8001/services/user-service/plugins \
     --data "name=rate-limiting" \
     --data "config.minute=5"

Advantages of Kong

1. Extensibility: Rich plugin ecosystem for easy customization.
2. Performance: Built on NGINX, ensuring low latency.
3. Scalability: Clustering and load balancing support high traffic volumes.

Use Cases for Kong

1. Microservices Management: Acts as a unified entry point for multiple microservices.
2. Authentication Handling: Manages complex authentication workflows using built-in plugins.

2. NGINX as an API Gateway

NGINX is a high-performance web server and reverse proxy that can also function as an API Gateway. It offers flexibility, low latency, and excellent request handling capabilities.

Key Features of NGINX

1. High Throughput
   • NGINX can handle a large number of concurrent connections, making it ideal for high-traffic applications.
2. Customizable Configuration
   • NGINX configurations are highly flexible, allowing routing, caching, load balancing, and security settings to be customized.
3. Load Balancing
   • NGINX can distribute traffic across multiple backend servers, enhancing availability and performance.

How NGINX Works as an API Gateway

NGINX acts as a reverse proxy, routing requests based on defined configurations and handling load balancing, caching, and authentication.

Setting Up NGINX as an API Gateway

1. Install NGINX
   • Install NGINX using package managers like apt or yum.

   sudo apt update
   sudo apt install nginx

2. Configure NGINX
   • Edit the NGINX configuration file (/etc/nginx/nginx.conf):

   server {
       listen 80;
       location /api/users {
           proxy_pass http://user-service:8080;
           proxy_set_header Host $host;
           proxy_set_header X-Real-IP $remote_addr;
       }
   }

3. Enable Rate Limiting
   • Add rate limiting configuration:

   http {
       limit_req_zone $binary_remote_addr zone=one:10m rate=5r/s;
       server {
           location /api/users {
               limit_req zone=one burst=10;
               proxy_pass http://user-service:8080;
           }
       }
   }

Advantages of NGINX

1. Performance: Optimized for handling high loads with minimal resource usage.
2. Flexibility: Highly configurable for various tasks, including caching and load balancing.
3. Security: Can enforce SSL termination, IP whitelisting, and rate limiting.

Use Cases for NGINX

1. Simple API Management: Best suited for basic API Gateway functionalities like routing and load balancing.
2. Low-Latency Applications: NGINX is ideal for applications requiring minimal latency.

3. AWS API Gateway

AWS API Gateway is a fully managed service provided by AWS that allows developers to create, deploy, and manage APIs at scale.

Key Features of AWS API Gateway

1. Fully Managed
   • AWS handles the infrastructure, scalability, and security, reducing operational overhead.
2. Integration with AWS Services
   • Seamless integration with AWS Lambda, S3, DynamoDB, and other AWS services.
3. Support for RESTful and WebSocket APIs
   • Supports both REST and WebSocket protocols, enabling different communication styles.

How AWS API Gateway Works

AWS API Gateway manages API requests, handles scaling, and integrates with AWS Lambda for backend processing.

Setting Up AWS API Gateway

1. Create an API
   • Use the AWS Management Console or CLI to create a new API.

   aws apigateway create-rest-api --name 'UserAPI'

2. Define Resources and Methods
   • Define resources like /users and set up methods (e.g., GET, POST).
3. Integrate with Backend
   • Integrate API Gateway with backend services such as AWS Lambda:

   aws apigateway put-integration \
     --rest-api-id <api_id> \
     --resource-id <resource_id> \
     --http-method POST \
     --type AWS_PROXY \
     --integration-http-method POST \
     --uri arn:aws:apigateway:<region>:lambda:path/2015-03-31/functions/<lambda_arn>/invocations

4. Deploy the API
   • Deploy the API to an environment (e.g., "prod" or "dev").

Advantages of AWS API Gateway

1. Scalability: Automatically scales to handle any number of requests.
2. Security: Supports IAM, Lambda authorizers, and resource policies.
3. Monitoring: Integrated with AWS CloudWatch for metrics and logs.

Use Cases for AWS API Gateway

1. Serverless Applications: Ideal for integrating with AWS Lambda and managing serverless workflows.
2. REST and WebSocket APIs: Best suited for building both synchronous and asynchronous APIs.

Comparison Table

Feature	Kong	NGINX	AWS API Gateway
Type	Open-source	Open-source	Managed Service
Plugins	Extensive	Limited	AWS Integrations
Setup Complexity	Moderate	Moderate	Low
Scalability	High	High	Automatic
Security	High	Moderate	Very High

FAQs

Q1: Which tool is best for large-scale deployments?
AWS API Gateway is ideal for large-scale, serverless, and cloud-native applications, thanks to its automatic scaling and

integration with AWS services.

Q2: Can I use NGINX and Kong together?
Yes, NGINX can act as a reverse proxy for Kong, handling SSL termination, while Kong manages authentication, routing, and rate limiting.

Q3: Is Kong suitable for on-premises deployment?
Yes, Kong is highly suitable for on-premises deployments, offering flexibility, customization, and high performance.

Q4: How does rate limiting differ across these tools?

• Kong: Uses plugins for rate limiting, offering granular control.
• NGINX: Uses built-in configurations, suitable for simple rate limiting.
• AWS API Gateway: Offers throttling and burst rate settings through the console or API.

Conclusion

Kong, NGINX, and AWS API Gateway each offer unique strengths as API Gateway tools. Kong excels in extensibility and customization, NGINX is known for its performance and flexibility, while AWS API Gateway is best for cloud-native, managed solutions.