【spring cloud 介绍】

Spring Cloud是一系列框架的有序集合。它利用Spring Boot的开发便利性巧妙地简化了分布式系统基础设施的开发，如服务发现注册、配置中心、消息总线、负载均衡、断路器、数据监控等，都可以用Spring Boot的开发风格做到一键启动和部署。Spring并没有重复制造轮子，它只是将目前各家公司开发的比较成熟、经得起实际考验的服务框架组合起来，通过Spring Boot风格进行再封装屏蔽掉了复杂的配置和实现原理，最终给开发者留出了一套简单易懂、易部署和易维护的分布式系统开发工具包。

 

Spring Cloud

Spring Cloud provides tools for developers to quickly build some of the common patterns in distributed systems (e.g. configuration management, service discovery, circuit breakers, intelligent routing, micro-proxy, control bus, one-time tokens, global locks, leadership election, distributed sessions, cluster state). Coordination of distributed systems leads to boiler plate patterns, and using Spring Cloud developers can quickly stand up services and applications that implement those patterns. They will work well in any distributed environment, including the developer's own laptop, bare metal data centres, and managed platforms such as Cloud Foundry.

 

SpringCloud分布式开发五大神兽

服务发现——Netflix Eureka

客服端负载均衡——Netflix Ribbon

断路器——Netflix Hystrix

服务网关——Netflix Zuul

分布式配置——Spring Cloud Config

 

 

 

 

Spring Cloud builds on Spring Boot by providing a bunch of libraries that enhance the behaviour of an application when added to the classpath. You can take advantage of the basic default behaviour to get started really quickly, and then when you need to, you can configure or extend to create a custom solution.

 

Features

Spring Cloud focuses on providing good out of box experience for typical use cases and extensibility mechanism to cover others.

Distributed/versioned configuration

Service registration and discovery

Routing

Service-to-service calls

Load balancing

Circuit Breakers

Global locks

Leadership election and cluster state

Distributed messaging

 

 

Spring Cloud的子项目，大致可分成两类，

一类是对现有成熟框架”Spring Boot化”的封装和抽象，也是数量最多的项目；

第二类是开发了一部分分布式系统的基础设施的实现，如Spring Cloud Stream扮演的就是kafka, ActiveMQ这样的角色。对于我们想快速实践微服务的开发者来说，第一类子项目就已经足够使用，如：

Spring Cloud Netflix

是对Netflix开发的一套分布式服务框架的封装，包括服务的发现和注册，负载均衡、断路器、REST客户端、请求路由等。

 

Spring Cloud Config

将配置信息中央化保存, 配置Spring Cloud Bus可以实现动态修改配置文件

 

Spring Cloud Bus

分布式消息队列，是对Kafka, MQ的封装

 

Spring Cloud Security

对Spring Security的封装，并能配合Netflix使用

 

Spring Cloud Zookeeper

对Zookeeper的封装，使之能配置其它Spring Cloud的子项目使用

 

Spring Cloud Eureka

Spring Cloud Eureka 是 Spring Cloud Netflix 微服务套件中的一部分，它基于Netflix Eureka 做了二次封装，主要负责完成微服务架构中的服务治理功能。