API Gateway acts as a single entry point for all client requests to access backend APIs. It processes requests in two main ways: either by routing them directly to the appropriate service or by distributing (fanning out) the request to multiple services. Spring Cloud API Gateway supports one-size-fits-all style API.

• Getting Started
• Architecture
• Usage
• How to contribute
• Built with Dependencies
• Code of Conduct
• Contributors
• Security Contact Information
• Support
• Troubleshooting
• License
• Announcements

Spring Cloud Gateway provides 2 ways to configure the routes with gateway.

• Static Routing - User has to manually configure the route definitions in the application.yml
• Dynamic Routing - Api-registry-common has the capability to read the open api annotations mentioned on the endpoints and creates the route definitions and stores in postgressql database

To build the project in the local working directory after the project has been cloned/forked, run:

mvn clean install

from the command line interface.

The list of tools required to build and run the project:

1. Java 21
2. Apache Maven 3.8 or higher

How to set up Maven

Install Java

checkstyle.xml is the coding standard to follow while writing new/updating existing code.

Checkstyle plugin maven-checkstyle-plugin:3.2.1 is integrated in pom.xml which runs in the validate phase and check goal of the maven lifecycle and fails the build if there are any checkstyle errors in the project.

To run the checkstyle plugin, run the below maven command.

mvn checkstyle:check

To run the tests for this system run the below maven command.

mvn test

Or run a specific test

mvn test -Dtest="TheFirstUnitTest"

To run a method from within a test

mvn test -Dtest="TheSecondUnitTest#whenTestCase2_thenPrintTest2_1"

We can deploy this component as a Kubernetes pod by installing api-gateway and api-registry charts.

Link: Charts

Sequence diagram of api-gateway-spring:

1. API-Gateway provides a robust solution for managing and routing HTTP request in microservice architecture. It dynamically registers routes and applies filters to validate requests and responses. Also offers built-in resilience and monitoring features to ensure scalable and reliable API management.

2. Spring Cloud API gateway does provide single entry point for all clients to allow access of backend APIs. The API gateway handles requests in one of two ways. Some requests are simply proxied/routed to the appropriate service. It handles other requests by fanning out to multiple services. Spring Cloud API gateway, also provide a one-size-fits-all style API, the API gateway can expose a different API for each client.

3. The API gateway also implement security, e.g. verify that the client is authorized to perform the request by validating the Oath2 token(JWT).A variation of this pattern is the Backends for frontends pattern. It defines a separate API gateway for each kind of client.

4. Spring Cloud Gateway features:

• Built on Spring Framework 5, Project Reactor and Spring Boot 2.0
• Able to match routes on any request attribute.
• Predicates and filters are specific to routes.
• Circuit Breaker integration.
• Spring Cloud Discovery Client integration
• Easy to write Predicates and Filters
• Request Rate Limiting
• Path Rewriting
• Response Caching

• Spring - Web framework used for building the application
• Spring cloud Gateway – API Gateway for routing and filtering requests
• Maven - Build tool used for dependency management
• PostgreSQL - Relational database
• MongoDB - NoSQL document database
• Apache Common - Provides utility classes for various Java operations
• Jackson - Library for parsing and generating JSON
• Logback - Concrete logging implementation used with SLF4J
• slf4j - Logging facade providing abstraction for various logging frameworks
• Mockito - Mocking framework for testing
• JUnit5 - Unit testing framework
• Lombok - Auto-generates Java boilerplate code (e.g., getters, setters, builders)
• Redis - In-memory data store used for caching & Rate Limiting
• Spring doc Open-Api - Automatically generates interactive API documentation (Swagger UI) from Spring controllers

Please read CONTRIBUTING.md for details on our contribution guidelines, and the process for submitting pull requests to us.

Please read CODE_OF_CONDUCT.md for details on our code of conduct, and the process for submitting pull requests to us.

• Abhishek Kumar - Initial work

The list of contributors who participated in this project.

Please read SECURITY.md to raise any security related issues.

Contact the project developers via the project's "dev" list - https://accounts.eclipse.org/mailing-list/ecsp-dev

Please read CONTRIBUTING.md for details on how to raise an issue and submit a pull request to us.

This project is licensed under the Apache-2.0 License - see the LICENSE file for details

All updates to this component are present in our releases page. For the versions available, see the tags on this repository.