API Gateway Service

Overview

The API Gateway Service acts as the single entry point for all microservices in the ecosystem. It provides a unified interface for clients, handling routing, load balancing, and service discovery integration. Built with Spring Cloud Gateway, it dynamically routes requests to the appropriate backend services registered with the Eureka Server.

Features

• Centralized Entry Point: All external requests go through the gateway, simplifying the client-side logic.
• Dynamic Routing: Automatically routes requests to microservices based on service IDs registered in Eureka.
• Service Discovery Integration: Seamlessly integrates with Eureka Server to discover available service instances.
• Load Balancing: Distributes traffic across multiple instances of a service using client-side load balancing.
• Path Rewriting: Automatically strips prefixes (e.g., /api/compliance) before forwarding requests to the downstream services.

Tech Stack

• Java 17
• Spring Boot 3.5.7
• Spring Cloud Gateway
• Spring Cloud Netflix Eureka Client
• Maven

Configuration

The service is configured in application.yml. Key configurations include:

• Server Port: 8082
• Application Name: api-gateway
• Eureka Server URL: http://localhost:8761/eureka/

Routing Rules

The gateway is configured with the following routes:

Service Name	Path Predicate	Target Service ID
Compliance Service	/api/compliance/**	compliance-regulatory-service
Fraud Detection Service	/api/fraud/**	fraud-detection-service
Notification Service	/api/notification/**	notification-service
Risk Scoring Service	/api/risk/**	risk-scoring-service
Transaction Ingestion	/api/ingestion/**	transaction-ingestion-service
Transaction Orchestration	/api/orchestration/**	transaction-orchestration-service

Note: The gateway strips the first 2 path segments (e.g., /api/compliance) before forwarding the request.

Getting Started

Prerequisites

• Java 17 or higher
• Maven
• Eureka Server must be running on port 8761.

Installation

1. Clone the repository.
2. Navigate to the api-gateway directory.

Running the Service

You can run the service using Maven:

mvn spring-boot:run

Or build the JAR and run it:

mvn clean package
java -jar target/api-gateway-0.0.1-SNAPSHOT.jar

The service will start on http://localhost:8082.

Usage

Once the gateway and all microservices are running, you can access them via the gateway URL:

• Compliance: http://localhost:8082/api/compliance/...
• Fraud: http://localhost:8082/api/fraud/...
• Notification: http://localhost:8082/api/notification/...
• Risk: http://localhost:8082/api/risk/...
• Ingestion: http://localhost:8082/api/ingestion/...
• Orchestration: http://localhost:8082/api/orchestration/...

Health Check

You can check the status of the gateway and its connection to Eureka by accessing the actuator endpoints (if enabled) or checking the logs for successful registration with the Eureka Server.