无法使用 API Gateway Spring Cloud 调用实际服务答案

【问题标题】：Unable to make a call to actual service using API Gateway Spring Cloud无法使用 API Gateway Spring Cloud 调用实际服务
【发布时间】：2021-07-26 04:07:05
【问题描述】：

我正在使用 Spring Boot v2.4.2.RELEASE 开发 Spring Boot 微服务，但无法调用通过 API 网关提供实际服务。源代码参考取自这里 - https://www.youtube.com/watch?v=BnknNTN8icw&t=1s，仅使用最新的依赖项

API 网关代码 - MainApp.java

@SpringBootApplication
@EnableEurekaClient
public class CloudApiGatewayApplication {

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

    @Bean
    public ServerCodecConfigurer serverCodecConfigurer() {
        return ServerCodecConfigurer.create();
    }
}

bootstrap.yml

spring:
  cloud:
    config:
      enabled: true
      uri: http://localhost:9296

application.yml

server:
  port: 9191

eureka:
  client:
    register-with-eureka: true
    fetch-registry: true
    service-url:
      defaultZone: http://localhost:8761/eureka
  instance:
    hostname: localhost

spring:
  application:
    name: api-gateway
  cloud:
    gateway:
      routes:
        - id: user-service
          uri: lb://user-service
          predicates:
            - Path=/users/**
            
        - id: department-service
          uri: lb://department-service
          predicates:
            - Path=/departments/**
            
      discovery:
        locator:
          lower-case-service-id: true
          enabled: true

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.4.2</version>
        <relativePath /> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.example</groupId>
    <artifactId>cloud-api-gateway</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>cloud-api-gateway</name>
    <description>Demo project for Spring Boot</description>
    <properties>
        <java.version>11</java.version>
        <spring-cloud.version>2020.0.2</spring-cloud.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-config-server</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-gateway</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-bootstrap</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>${spring-cloud.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

bootstrap.yml

spring:
  cloud:
    config:
      enabled: true
      uri: http://localhost:9296

application.properties

server.port=9001
spring.application.name=department-service

#spring.zipkin.base-url=http://127.0.0.1:9411/

eureka.client.register-with-eureka=true
eureka.client.fetch-registry=true
eureka.instance.ip-address=true
eureka.client.service-url.defaultZone=http://localhost:8761/eureka
eureka.instance.hostname=localhost

DepartmentController.java

@RestController
@RequestMapping("/departments")
public class DepartmentController {

    @Autowired
    private DepartmentService departmentService;

    @PostMapping("/")
    public Department saveDepartment(@RequestBody Department department) {
        return departmentService.saveDepartment(department);
    }

    @GetMapping("/{id}")
    public Department findDepartmentById(@PathVariable("id") Long departmentId) {
        return departmentService.findDepartmentById(departmentId);
    }
}

【问题讨论】：

使用 Eureka UI 中的所有可用服务？共享网关和部门服务的堆栈跟踪
嘿，是的，所有服务都在 eureka 中可用，想知道为什么连日志都没有出现在 API 网关上，会尝试在某处发布整个代码..

标签： spring spring-boot api-gateway

【解决方案1】：

将以下属性添加到 API-GATEWAY 的 application.yml 以确保网关发现手动设置为 true 并且两个服务名称全部大写：

server:
  port: 9191

spring:
  application:
    name: API-GATEWAY 
  cloud.gateway:
    discovery:
      locator:
        enabled: true
        lowerCaseServiceId: true
    routes:
    - id: users
      uri: lb://USER-SERVICE
      predicates:
        - Path=/users/**
    - id: albums
      uri: lb://DEPARTMENT-SERVICE
      predicates:
        - Path=/departments/**

【讨论】：