spring cloud
Spring Cloud is a microservice architecture development toolbox based on Spring Boot, which can help developers quickly build a microservice architecture. It provides a variety of functions, including service registration and discovery, load balancing, circuit breakers, configuration centers, message buses, etc., which can greatly simplify the work of developers in the microservice architecture.
Architecture of Spring Cloud
The following is the architecture of Spring Cloud:
Service Registration and Discovery
Spring Cloud uses Netflix's open source Eureka to implement service registration and discovery. Eureka is a REST-based service that can register, unregister and discover services. It provides a highly available service registry and can automatically update service information to the registry.
load balancing
Spring Cloud uses Netflix's open source Ribbon to achieve client load balancing. Ribbon is a load balancer based on HTTP and TCP, which can automatically distribute client requests to different servers.
fuse
Spring Cloud uses Netflix's open source Hystrix to implement circuit breakers. Hystrix is a library for dealing with delay and fault tolerance in distributed systems. It can protect the availability and stability of the entire service and prevent service avalanche.
configuration center
Spring Cloud uses Git or SVN to implement the configuration center. The configuration center can centrally manage the configuration information of all services, and it can be dynamically updated, so that the services can quickly respond to changes.
message bus
Spring Cloud uses Spring Cloud Bus to implement the message bus. Spring Cloud Bus can connect all microservice instances, so that configuration changes can be broadcast to the entire microservice architecture.
API Gateway
Spring Cloud uses Netflix's open source Zuul to implement the API gateway. Zuul is a filter-based gateway that can implement functions such as dynamic routing, security authentication, and traffic monitoring. It provides a unified entry and exit, allowing clients to easily access microservices.
In short, Spring Cloud is a feature-rich microservice framework that can help developers quickly build a microservice architecture and improve development efficiency and service quality.
Core Layer, Service Governance Layer and Application Layer
Spring Cloud is a Spring Boot-based microservice architecture development kit that provides a set of components and tools for building distributed systems.
The architecture of Spring Cloud is mainly divided into three layers: core layer, service management layer and application layer.
core layer
The core layer of Spring Cloud contains the core components of Spring Boot and Spring Cloud, including:
- Spring Boot: Spring Boot is an extension of the Spring Framework, which provides a tool for quickly building applications, and also includes some common dependencies and default configurations.
- Spring Cloud Commons: Spring Cloud Commons is one of the core components of Spring Cloud, providing the basic building blocks of Spring Cloud, including functions such as service discovery, configuration management, and routing.
- Spring Cloud Config: Spring Cloud Config is a distributed configuration management tool that allows developers to separate the configuration of the application from the code and store it centrally in a unified place.
- Spring Cloud Bus: Spring Cloud Bus is another core component of Spring Cloud, which provides a tool for messaging in the microservice architecture, including functions such as message broadcasting and message bus.
- Spring Cloud Stream: Spring Cloud Stream is a framework for building a message-driven microservice architecture, which provides a messaging-based programming model and a set of APIs for building message channels.
Service Governance Layer
The service governance layer is an important part of Spring Cloud. It mainly includes components such as service registration and discovery, load balancing, circuit breakers and gateways, including:
- Spring Cloud Netflix: Spring Cloud Netflix is the service governance layer component of Spring Cloud, which provides a set of tools for building distributed systems, including service registration and discovery, load balancing, circuit breakers and gateways.
- Spring Cloud Eureka: Spring Cloud Eureka is a REST-based service governance component open sourced by Netflix. It provides service registration and discovery functions, and can automatically manage the registration and discovery of microservices.
- Spring Cloud Ribbon: Spring Cloud Ribbon is a load-balancing client component that can automatically route requests between multiple service instances, thereby improving system availability and fault tolerance.
- Spring Cloud Hystrix: Spring Cloud Hystrix is a circuit breaker component that can build resilience and fault tolerance between services, and protect services from crashing due to failed services through the circuit breaker mechanism.
- Spring Cloud Zuul: Spring Cloud Zuul is a reverse proxy-based gateway component that routes external requests to internal services and provides load balancing, security, and monitoring functions.
application layer
The application layer is the top layer of Spring Cloud, which contains the actual microservice application, including functions such as business logic and data access. At the application layer, developers can use various components and tools provided by Spring Cloud to build their own microservice applications, such as using Spring Cloud Feign to simplify the invocation of RESTful services, using Spring Cloud Sleuth for distributed tracking, and using Spring Cloud Stream to build message-driven applications and more.
In short, Spring Cloud's architecture provides a complete microservice architecture development kit that can help developers quickly build scalable, highly available, easy-to-maintain and reliable distributed systems.
How to build a spring cloud application
To build a Spring Cloud application, follow these steps:
Install and configure the development environment
First, the development environment needs to be installed and configured. The following software and tools need to be installed:
JDK 8 or later
Maven or Gradle build tool
IDE, such as IntelliJ IDEA or Eclipse, etc.
Create a Spring Boot project
Next, a Spring Boot project needs to be created as the basis for the Spring Cloud application. You can use the Spring Initializr tool to quickly create a Spring Boot project and select the required dependencies, such as Spring Cloud Config, Eureka, Feign, Hystrix, etc.
Configure Spring Cloud components
After creating the Spring Boot project, you need to add the configuration of Spring Cloud components to the project. These configurations typically include:
Service registration and discovery: Configure a service registry such as Eureka or Consul, and register the application into the registry.
Service call: Configure client components such as Feign or RestTemplate to call APIs of other microservices.
Circuit Breaker: Configure circuit breaker components such as Hystrix to prevent cascading failures between services.
Configuration management: Configure configuration centers such as Spring Cloud Config to centrally manage application configuration information.
API Gateway: Configure API gateways such as Zuul to provide functions such as security, load balancing, and routing.
Write business logic and data access code
After completing the configuration of Spring Cloud components, you need to write business logic and data access codes to realize the functions of the application.
Run and test the application
Finally, applications can be built and packaged using Maven or Gradle, and run and tested locally or in a cloud environment. Application performance and health can be monitored using API documentation tools like Swagger or distributed tracing tools like Spring Cloud Sleuth.
In short, building a Spring Cloud application requires the completion of the above steps, and reasonable configuration and use of Spring Cloud components according to specific needs and scenarios.
Dubbo
Dubbo is a high-performance, lightweight microservice framework open sourced by Alibaba. It supports multiple protocols, load balancing and fault tolerance mechanisms, and can help developers build distributed applications.
The following is the architecture of Dubbo:
registration center
Dubbo's registry can be used for service registration and discovery, and it can provide multiple registry implementations, such as Zookeeper, Redis, Simple, etc. Dubbo uses the registry to manage the relationship between service providers and service consumers, so that service providers and consumers can dynamically discover and call each other.
service provider
Dubbo's service provider registers its services with the registration center and monitors requests from consumers. When a request comes, the service provider will select a server to process the request according to the load balancing strategy, and use the fault tolerance mechanism to handle the request failure.
service consumer
Dubbo's service consumers obtain the service provider's information from the registration center and send requests to the service provider. Service consumers can select a service provider to handle requests through Dubbo's load balancing strategy, and use fault tolerance mechanisms to handle request failures.
monitoring Center
Dubbo's monitoring center can be used to monitor the running status and performance indicators of services. It can provide a variety of monitoring center implementations, such as Dubbo Admin, Zookeeper, Elasticsearch, etc. The monitoring center can help developers quickly locate service failures and provide suggestions for performance optimization.
Dubbo protocol
The Dubbo protocol is the core protocol of Dubbo, which is a high-performance, low-latency protocol based on TCP. The Dubbo protocol uses the Hessian2 protocol to serialize data, which can effectively improve communication efficiency and performance.
Dubbo extension point
Dubbo's extension point is a plug-in mechanism that can help developers customize and extend Dubbo's functions. Dubbo provides a variety of extension points, such as protocols, load balancing, fault tolerance, serialization, etc., to meet different needs.
In short, Dubbo is a microservice framework with rich functions and excellent performance, which can help developers quickly build distributed applications. It provides a variety of features, such as registration center, service provider, service consumer, monitoring center, Dubbo protocol, extension points, etc., to meet the needs of different scenarios.
How to build a Dubbo application?
To build a Dubbo application from 0, you need to follow the steps below:
1. Install ZooKeeper
Dubbo uses ZooKeeper as the registration center, so ZooKeeper needs to be installed first. You can download the latest version of ZooKeeper from the official website of ZooKeeper (https://zookeeper.apache.org/), and install and configure it according to the official documentation.
2. Create a Maven project
Use Maven to create a Java project, you can use an IDE such as Eclipse or IntelliJ IDEA to create a project, you can also use the Maven command line tool to create a project. Add the dependencies of Dubbo and ZooKeeper to the pom.xml file of the project, for example:
<dependencies>
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>dubbo</artifactId>
<version>2.7.8</version>
</dependency>
<dependency>
<groupId>org.apache.zookeeper</groupId>
<artifactId>zookeeper</artifactId>
<version>3.5.7</version>
</dependency>
</dependencies>
3. Write Dubbo configuration file
Create a Dubbo configuration file in the src/main/resources directory of the project, such as dubbo.properties or dubbo.xml, which includes the basic configuration information of the Dubbo application, such as application name, registration center address, protocol, etc., for example:
dubbo.properties：
dubbo.application.name=dubbo-demo-provider
dubbo.registry.address=zookeeper://127.0.0.1:2181
dubbo.protocol.name=dubbo
dubbo.protocol.port=20880
4. Write the service provider code
Write Dubbo's service provider code in the project, for example:
public interface HelloService {
String sayHello(String name);
}
public class HelloServiceImpl implements HelloService {
public String sayHello(String name) {
return "Hello, " + name;
}
}
public class Application {
public static void main(String[] args) throws Exception {
// 创建服务实现对象
HelloService helloService = new HelloServiceImpl();
// 发布服务
ServiceConfig<HelloService> service = new ServiceConfig<>();
service.setInterface(HelloService.class);
service.setRef(helloService);
service.export();
// 阻塞当前线程，避免服务停止
System.in.read();
}
}
5. Write service consumer code
Write Dubbo's service consumer code in the project, for example:
public class Application {
public static void main(String[] args) {
// 引用服务
ReferenceConfig<HelloService> reference = new ReferenceConfig<>();
reference.setInterface(HelloService.class);
reference.setUrl("dubbo://127.0.0.1:20880");
// 调用服务
HelloService helloService = reference.get();
String result = helloService.sayHello("Dubbo");
System.out.println(result);
}
}
6. Start the service provider and service consumer
The service provider and service consumer can be started separately, for example by running the Application class in the IDE, or by running the project using the Maven command line tools. If everything is normal, the service provider will register the service to the ZooKeeper center, and the service consumer will obtain the service address from the registration center and call the service.
The above are the basic steps to build a Dubbo application. It should be noted that the configuration and use of Dubbo are relatively complicated. It is recommended to read the official documentation of Dubbo carefully in order to better understand and use Dubbo.
Spring Cloud vs Dubbo
Both Spring Cloud and Dubbo are popular microservice frameworks. They have some similarities, such as supporting service registration and discovery, load balancing, fault tolerance mechanisms, etc., but there are also some differences.
architectural pattern
Spring Cloud performs service communication based on the RESTful HTTP protocol, and uses an API gateway based on the HTTP protocol to implement service routing, load balancing, and flow control. Dubbo is based on the RPC protocol for service communication and uses the Dubbo protocol for data transmission.
registration center
Spring Cloud supports multiple registry implementations, such as Eureka, Consul, Zookeeper, etc., and you can choose different registry centers according to different scenarios. Dubbo also supports multiple registry implementations, such as Zookeeper, Redis, Simple, etc.
Service Governance
Spring Cloud provides a more complete service governance solution, including service routing, circuit breaking, degradation, current limiting, link tracking, service monitoring, etc. Dubbo pays more attention to the service call process and provides a more comprehensive service call framework, including multiple load balancing strategies, fault tolerance mechanisms, protocol extensions, etc.
Component extension
Spring Cloud provides more component extensions, such as Spring Cloud Config, Spring Cloud Stream, Spring Cloud Security, etc., which can provide developers with more complete microservice solutions. Dubbo pays more attention to the extensibility of components, and provides a variety of extension points, which can customize and expand Dubbo's functions according to requirements.
In short, both Spring Cloud and Dubbo are excellent microservice frameworks, and they differ in architectural patterns, registration centers, service governance, and component extensions. Developers can choose different frameworks according to their needs and scenarios.