Introduction on Zuul API gateway

Zuul Server is an API Gateway application. It handles all the requests and performs the dynamic routing of microservice applications. It works as a front door for all the requests. It is also known as Edge Server. Zuul is built to enable dynamic routing, monitoring, resiliency, and security. For an example api/products are mapped to the product service and /api/user is mapped to the user services.

The reason for the Zuul is the volume and variety of Netflix API traffic sometimes result in production issues that arises quickly and without warning. So we need a system that allows us to rapidly change behavior in order to react to these situations. Registry server is called Eureka registry in different microservice application. It deployed different hosts and ports.

Microservices is known as microservice architecture is a application as a collection of services. It is high maintain and testing then independently deployed; mainly used in business services. All the microservices will be deployed in a private network so information also very safety.

Eureka Server is an application that holds information about all client-service applications. Microservice will register into the Eureka server and the Eureka server knows all the client applications running on each port and IP address. Eureka Server is also known as Discovery Server.

All the microservices are registered in the Netflix Eureka. API gateway is one of the microservice it’s a part of the Spring cloud.All the services are available in the Netflix Eureka Registry.

UI service request will go to the Zuul API Gateway. Zuul will route all the requests to the corresponding Micro Service.Gateway should provide Authorization and Authentication to the routes. Filter all the requests for the user check information is authorized or unauthorized then pass through route to the microservice.

Zuul have a four types of filter compounds. It uses to intercept the traffic in different timeline for particular transaction for request processing. Pre filters for before the request is routed. Post filters invoked after request is routed.route filters are directly request to route. Error filters invoked error is occurs.

Gateway have more responsible for back end application.Micro-service security in the gateway layer to protect the actual services, micro-services insights and monitoring of all the traffic.

Dynamic Routing can router requests to different back-end clusters.allocating capacity for each type of request and dropping requests. Building some responses directly to the internal cluster for processing.

Create a zuul API Gateway no changes required in Eureka Service. Consumes a producer service and consumer service. Route the requests from UI to the corresponding producer service.In this zuul API gateway is high security for the back end services.