Spring Cloud GateWay

Introduction to the

• Current limiting
• The path to rewrite
• Dynamic routing

Compared with Zuul

• Zuul is a Netflix product and GateWay is a Spring family product
• Zuul1 does not support long connections, such as Websockets
• GateWay Supports traffic limiting
• GateWay is developed based on Netty, which realizes asynchronous and non-blocking, occupies less resources and has stronger performance

Microservice usage

GateWay can be used in two ways

• The encoding type
• Yml type

Create a new project, add a dependency, be careful not to add a WebMVC dependency

<dependencies>
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-loadbalancer</artifactId>
        <version>2.2.4. RELEASE</version>
    </dependency>
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-gateway</artifactId>
    </dependency>
    <dependency>
        <groupId>com.alibaba.cloud</groupId>
        <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
        <version>2.2.4. RELEASE</version>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-test</artifactId>
        <scope>test</scope>
    </dependency>
</dependencies>
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The encoding type

@SpringBootApplication
public class GatewayApplication {

    public static void main(String[] args) {
        SpringApplication.run(GatewayApplication.class, args);
    }

    @Bean
    RouteLocator routeLocator(RouteLocatorBuilder builder) {
        return builder.routes()
                // Customize the route
                .route("southyin_route",r->r.path("hello1").uri("http://localhost:8888")) .build(); }}Copy the code

Yml type

Application configuration

spring:
  application:
    name: gateway
  cloud:
    nacos:
      discovery:
        server-addr: 192.168189.101.: 8848
    gateway:
      discovery:
        locator:
          enabled: true
logging:
  level:
    org.southyin.gateway: debug

server:
  port: 2020
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Start the project, access to test, here can access directly through http://localhost:2020/prover/hello1 application name to access, and automatic load balancing support

You can also define routes

spring:
  application:
    name: gateway
  cloud:
    nacos:
      discovery:
        server-addr: 192.168189.101.: 8848
    gateway:
      routes:
        - id: southyin_route # Route name, custom
          uri: http://localhost:8888 # forwarding address
          predicates: # define interface, is an array
            - Path=/hello1
      discovery:
        locator:
          enabled: true
logging:
  level:
    org.southyin.gateway: debug

server:
  port: 2020
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Visit the test as shown below

Predicate

This is one of the reasons Spring Cloud is so powerful, for example

1. Yml used Path to match

spring:
  cloud:
    gateway:
      routes:
        - id: southyin_route
          uri: http://localhost:8888
          predicates:
            - Path=/hello1
      discovery:
        locator:
          enabled: true
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2. The configured routes can also be matched by time

spring:
  cloud:
    gateway:
      routes:
        - id: southyin_route
          uri: http://localhost:8888
          predicates:
            - After=2021-09-05T01:01:01+08:00[Asia/Shanghai]
      discovery:
        locator:
          enabled: true
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Indicates that the request will be routed at 2021-09-05 09:01:01, and there are two keywords

• Before: Before a certain point in time
• “Between” : Two time points are separated by commas (,)

3. It can also be matched by request method

spring:
  cloud:
    gateway:
      routes:
        - id: southyin_route
          uri: http://localhost:8888
          predicates:
            - Method=GET
      discovery:
        locator:
          enabled: true
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Indicates that only GET requests will be routed

4. Request path matching can also be used

spring:
  cloud:
    gateway:
      routes:
        - id: southyin_route
          uri: http://localhost:8888
          predicates:
            - Path=/test/{segment}
      discovery:
        locator:
          enabled: true
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Indicates that the test prefix can be forwarded

5. Match parameters

spring:
  cloud:
    gateway:
      routes:
        - id: southyin_route
          uri: http://localhost:8888
          predicates:
            - Query=name
      discovery:
        locator:
          enabled: true
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Indicates that the request must have the name parameter to forward

spring:
  cloud:
    gateway:
      routes:
        - id: southyin_route
          uri: http://localhost:8888
          predicates:
            - Query=name,test.*
      discovery:
        locator:
          enabled: true
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The value representing the name parameter must start with test

The use of the Filter

There are two main categories of filters in Gateway:

• GatewayFilter
• GlobalFilter

spring:
  cloud:
    gateway:
      routes:
        - id: southyin_route
          uri: lb://provider # lb,loadBalance stands for automatic load balancing
          filters:
            - AddRequestParameter=name,southyin
          predicates:
            - Method=GET
      discovery:
        locator:
          enabled: true
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This filter indicates that the name parameter, value southyin, is automatically added when forwarding