Netflix/zuul

Netflix/zuul

https://github.com/Netflix/zuul

Zuul is an L7 application gateway that provides capabilities for dynamic routing, monitoring, resiliency, security, and more. Please view the wiki for usage, information, HOWTO, etc https://github.com/Netflix/zuul/wiki

Here are some links to help you learn more about the Zuul Project. Feel free to PR to add any other info, presentations, etc.

 

微服务-Zuul服务网关框架

https://www.bilibili.com/video/BV1fy4y1e7go?spm_id_from=333.788.videopod.episodes&vd_source=57e261300f39bf692de396b55bf8c41b&p=2

 

 

SpringCloud之Zuul网关原理及其配置

https://www.cnblogs.com/jing99/p/11696192.html

 

Zuul是spring cloud中的微服务网关。网关： 是一个网络整体系统中的前置门户入口。请求首先通过网关，进行路径的路由，定位到具体的服务节点上。

　　Zuul是一个微服务网关，首先是一个微服务。也是会在Eureka注册中心中进行服务的注册和发现。也是一个网关，请求应该通过Zuul来进行路由。

　　Zuul网关不是必要的。是推荐使用的。

　　使用Zuul，一般在微服务数量较多（多于10个）的时候推荐使用，对服务的管理有严格要求的时候推荐使用，当微服务权限要求严格的时候推荐使用。

Zuul网关的作用

　　网关有以下几个作用：

• 统一入口：未全部为服务提供一个唯一的入口，网关起到外部和内部隔离的作用，保障了后台服务的安全性。
• 鉴权校验：识别每个请求的权限，拒绝不符合要求的请求。
• 动态路由：动态的将请求路由到不同的后端集群中。
• 减少客户端与服务端的耦合：服务可以独立发展，通过网关层来做映射。

　　　　

 

 

Get to Know Netflix's Zuul

https://dzone.com/articles/spring-cloud-netflix-zuul-edge-serverapi-gatewayga

Zuul is the front door for all requests from devices and websites to the backend of the Netflix streaming application. As an edge service application, Zuul is built to enable dynamic routing, monitoring, resiliency, and security.

 

Routing is an integral part of a microservice architecture. For example, /api/users is mapped to the user service and /api/shop is mapped to the shop service. Zuul is a JVM-based router and server side load balancer by Netflix.

The volume and diversity of Netflix API traffic sometimes results in production issues arising quickly and without warning. We need a system that allows us to rapidly change behavior in order to react to these situations.

Zuul uses a range of different types of filters that enables us to quickly and nimbly apply functionality to our edge service. These filters help us perform the following functions: 

• Authentication and Security: identifying authentication requirements for each resource.
• Insights and Monitoring: tracking meaningful data and statistics.
• Dynamic Routing: dynamically routing requests to different backend..
• Stress Testing: gradually increasing the traffic.
• Load Shedding: allocating capacity for each type of request and dropping requests.
• Static Response handling: building some responses directly.
• Multiregion Resiliency: routing requests across AWS regions.

Zuul contains multiple components:

• zuul-core: library that contains the core functionality of compiling and executing Filters.
• zuul-simple-webapp: webapp that shows a simple example of how to build an application with zuul-core.
• zuul-netflix: library that adds other NetflixOSS components to Zuul — using Ribbon for routing requests, for example.
• zuul-netflix-webapp: webapp which packages zuul-core and zuul-netflix together into an easy to use package.

Zuul gives us a lot of insight, flexibility, and resiliency, in part by making use of other Netflix OSS components:

• Hystrix is used to wrap calls to our origins, which allows us to shed and prioritize traffic when issues occur.
• Ribbon is our client for all outbound requests from Zuul, which provides detailed information into network performance and errors, as well as handles software load balancing for even load distribution.
• Turbine aggregates fine­grained metrics in real­time so that we can quickly observe and react to problems.
• Archaius handles configuration and gives the ability to dynamically change properties.

We can create a filter to route a specific customer or device to a separate API cluster for debugging. Prior to using Zuul, we were using Hadoop to query through billions of logged requests to find the several thousand requests we were interested in.

We have an automated process that uses dynamic Archaius configurations within a Zuul filter to steadily increase the traffic routed to a small cluster of origin servers. As the instances receive more traffic, we measure their performance characteristics and capacity.

Spring Cloud has created an embedded Zuul proxy to ease the development of a very common use case where a UI application wants to proxy calls to one or more back end services. This feature is useful for a user interface to proxy to the backend services it requires, avoiding the need to manage CORS and authentication concerns independently for all the backends.

To enable it, annotate a Spring Boot main class with @EnableZuulProxy, and this forwards local calls to the appropriate service. By convention, a service with the ID "users", will receive requests from the proxy located at /users.

The proxy uses Ribbon to locate an instance to forward to via discovery, and all requests are executed in a hystrix command, so failures will show up in Hystrix metrics, and once the circuit is open the proxy will not try to contact the service.

 

demo

https://github.com/piomin/sample-spring-microservices-new

Architecture

Our sample microservices-based system consists of the following modules:

• gateway-service - a module that Spring Cloud Netflix Zuul for running Spring Boot application that acts as a proxy/gateway in our architecture.
• config-service - a module that uses Spring Cloud Config Server for running configuration server in the native mode. The configuration files are placed on the classpath.
• discovery-service - a module that depending on the example it uses Spring Cloud Netflix Eureka or Spring Cloud Netlix Alibaba Nacos as an embedded discovery server.
• employee-service - a module containing the first of our sample microservices that allows to perform CRUD operation on in-memory repository of employees
• department-service - a module containing the second of our sample microservices that allows to perform CRUD operation on in-memory repository of departments. It communicates with employee-service.
• organization-service - a module containing the third of our sample microservices that allows to perform CRUD operation on in-memory repository of organizations. It communicates with both employee-service and organization-service.

The following picture illustrates the architecture described above.

 

https://github.com/rickiechina/Spring-Cloud-Full-Demo

https://github.com/KotlinSpringBoot/demo3_zuul_api_gateway

https://github.com/zzqfsy/spring-cloud-demo

https://github.com/lexburner/zuul-gateway-demo