1. Microservice architecture is an architectural pattern that divides applications into a set of small services, and the services coordinate and cooperate with each other to provide users with ultimate value
2. Each service runs in its own process, and a lightweight communication mechanism is used between services to communicate with each other
3. Each service is built around a specific business and can be independently deployed to a production environment, a production-like environment, etc.
4. A large and complex software application consists of one or more microservices. Each microservice in the system can be deployed independently, and each microservice is loosely coupled. Each microservice only focuses on completing one task and completing that task well
Advantages of microservices
Controllable complexity
Each microservice focuses on a single function, and each microservice can be fully controlled by a small-scale development team, which is easy to maintain high maintainability and development efficiency
Standalone deployment
Since microservices have independent running processes, each microservice can also be deployed independently, reducing the risk to the production environment and ultimately shortening the application delivery cycle
Flexible technology selection
Under the microservice architecture, technology selection is decentralized, and you can freely choose the most suitable technology stack. Since each microservice is relatively simple, even a complete refactoring of a microservice is feasible
Fault tolerance
When a component fails, under the traditional architecture of a single process, the fault is likely to spread within the process, resulting in a global unavailability of the application. Under the microservice architecture, the fault will be isolated in a single service. If well-designed, other services can achieve application-level fault tolerance through mechanisms such as retries and smooth degradation.
Expand
Monolithic architecture applications can also achieve horizontal expansion, that is, the entire application is completely copied to different nodes. When the different components of the application have differences in expansion requirements, the microservice architecture reflects its flexibility, because each service can be expanded independently according to actual needs.
Spring cloud introduction
Spring cloud is a collection of a series of frameworks. It uses the development convenience of spring boot to simplify the development of distributed system infrastructure.
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, You can use the spring boot development style to achieve one-click startup and deployment,
Spring cloud does not repeat the manufacturing of wheels. It just develops the more mature ones currently developed by various companies, and uses the spring boot style to repackage and shield the complex configuration and implementation principles.
spring cloud technical composition
1- eureka-microservice governance, service registration and discovery
2- ribbon —— load balancing, request retry
3- hystrix-circuit breaker, service degradation, fusing
4- feign —— ribbon + hystrix integration, and provide declarative client
5- hystrix dashboard and turbine —— hystrix data monitoring
6- zuul —— API gateway, provides a unified entrance to microservices, and provides unified authorization verification
