微服务-创建springcloud项目框架，主要是对gateway使用说明，看看gateway有什么用处

---

创建一个springcloud项目框架

搭建项目框架

注：框架是使用了nacos作为注册中心，要自己先搭建nacos
项目框架：

第一步：创建项目结构

idea创建项目结构：
父亲模块创建：
File->new->新建project，选择maven（不需要选择模板），下一步，输入项目名，finish就行了
子模块创建：
新建model，选择maven（不需要选择模板），下一步，输入项目名，finish就行了
idea新建图说：
1）File->new->新建project

2）new->新建model（右键项目目录新建）

3）选择maven（不需要选择模板），下一步

4）输入项目名，finish就行了

第二步：springcloud-gateway-example的pom.xml

打包方式：pom
maven管理包

<packaging>pompackaging>
<properties>
    <spring-boot.version>2.2.5.RELEASEspring-boot.version>
    <spring-cloud.version>Hoxton.SR8spring-cloud.version>
    <spring-cloud-alibaba.version>2.2.1.RELEASEspring-cloud-alibaba.version>
    <maven.compiler.source>1.8maven.compiler.source>
    <maven.compiler.target>1.8maven.compiler.target>
properties>

<dependencyManagement>
    <dependencies>
        <dependency>
            <groupId>org.springframework.bootgroupId>
            <artifactId>spring-boot-dependenciesartifactId>
            <version>${spring-boot.version}version>
            <type>pomtype>
            <scope>importscope>
        dependency>
        <dependency>
            <groupId>org.springframework.cloudgroupId>
            <artifactId>spring-cloud-dependenciesartifactId>
            <version>${spring-cloud.version}version>
            <type>pomtype>
            <scope>importscope>
        dependency>
        <dependency>
            <groupId>com.alibaba.cloudgroupId>
            <artifactId>spring-cloud-alibaba-dependenciesartifactId>
            <version>${spring-cloud-alibaba.version}version>
            <type>pomtype>
            <scope>importscope>
        dependency>
    dependencies>
dependencyManagement>

第三步：gateway-common的pom.xml

<dependencies>
    
    <dependency>
        <groupId>org.springframework.bootgroupId>
        <artifactId>spring-boot-starter-webartifactId>
    dependency>
    

    
    <dependency>
        <groupId>com.alibaba.cloudgroupId>
        <artifactId>spring-cloud-starter-alibaba-nacos-discoveryartifactId>
    dependency>
    <dependency>
        <groupId>com.alibaba.cloudgroupId>
        <artifactId>spring-cloud-starter-alibaba-nacos-configartifactId>
    dependency>
    

    <dependency>
        <groupId>org.projectlombokgroupId>
        <artifactId>lombokartifactId>
    dependency>

    
    <dependency>
        <groupId>org.slf4jgroupId>
        <artifactId>jcl-over-slf4jartifactId>
    dependency>
    <dependency>
        <groupId>org.slf4jgroupId>
        <artifactId>slf4j-apiartifactId>
    dependency>
    <dependency>
        <groupId>org.slf4jgroupId>
        <artifactId>slf4j-log4j12artifactId>
    dependency>
    

dependencies>

第四步：discovery-business1-server和discovery-business2-server的pom.xml

<dependencies>
    <dependency>
        <groupId>org.examplegroupId>
        <artifactId>gateway-commomartifactId>
        <version>${parent.version}version>
    dependency>
dependencies>
<build>
    <plugins>
        <plugin>
            <groupId>org.springframework.bootgroupId>
            <artifactId>spring-boot-maven-pluginartifactId>
            <executions>
                <execution>
                    <goals>
                        <goal>repackagegoal>
                    goals>
                execution>
            executions>
        plugin>
        <plugin>
            <artifactId>maven-compiler-pluginartifactId>
            <configuration>
                <source>1.8source>
                <target>1.8target>
            configuration>
        plugin>
    plugins>
build>

第五步：discovery-gateway-server的pom.xml

<dependencies>
    <dependency>
        <groupId>org.springframework.cloudgroupId>
        <artifactId>spring-cloud-starter-gatewayartifactId>
    dependency>
dependencies>
<build>
    <plugins>
        <plugin>
            <groupId>org.springframework.bootgroupId>
            <artifactId>spring-boot-maven-pluginartifactId>
            <executions>
                <execution>
                    <goals>
                        <goal>repackagegoal>
                    goals>
                execution>
            executions>
        plugin>
        <plugin>
            <artifactId>maven-compiler-pluginartifactId>
            <configuration>
                <source>1.8source>
                <target>1.8target>
            configuration>
        plugin>
    plugins>
build>

4.对服务discovery-business1-server和discovery-business2-server创建api接口

4.1 创建包org.example
4.2 创建启动类：Business1application

@SpringBootApplication
@EnableDiscoveryClient
@RestController
@RequestMapping("/bus1")
public class Business1Application {

    public static void main (String [] args){
        SpringApplication.run(Business1Application.class, args);
    }
    
    @RequestMapping("/1")
    public String getBus1() {
        return "你好：bus1";
    }
}

4.3 创建启动：Business2application

@SpringBootApplication
@EnableDiscoveryClient
@RestController
@RequestMapping("/bus2")
public class Business2application {
	public static void main (String [] args){
	    SpringApplication.run(Business1Application.class, args);
	}

	@RequestMapping("/1")
	public String getBus1() {
	    return "你好：bus2";
	}
}

5.对服务discovery-business1-server和discovery-business2-server创建bootstrap.yml

5.1discovery-business1-server创建yml

server:
  port: 8181

# 设置应用名称，便于在注册中心中查看
spring:
  application:
    name: business1-provider
  # 设置注册中心
  cloud:
    nacos:
      discovery:
        server-addr: 127.0.0.1:8848

5.2discovery-business2-server创建yml

server:
  port: 8182

# 设置应用名称，便于在注册中心中查看
spring:
  application:
    name: business2-provider
  # 设置注册中心
  cloud:
    nacos:
      discovery:
        server-addr: 127.0.0.1:8848

6.discovery-gateway-server服务

初次体验gateway

完整yml配置文件：

server:
  port: 8180
# 设置应用名称，便于在注册中心中查看
spring:
  application:
    name: gateway-server
  # 设置注册中心
  cloud:
       nacos:
          discovery:
            server-addr: 127.0.0.1:8848
    gateway:
      routes:
        - id: example-server
          uri: https://example.org/
          predicates:
            - Path=/test
        - id: business1-provider
          uri: http://localhost:8181/
          predicates:
            - Path=/bus2/**
        - id: business2-provider
          uri: lb://business2-provider
          predicates:
            - Path=/bus2/**

访问

• 浏览器直接输入：http://127.0.0.1:8180/test 就会转发到：https://example.org/test

• 浏览器直接输入：http://127.0.0.1:8180/bus1/1 就会转发到： http://localhost:8181/bus1/1

规则就是在predicates断言，如果判断断言为true，就会路由并打多出来的path拼接到uri的后面转发

主要配置说明

spring.cloud:
    gateway:
      routes:
        - id: example-server
          uri: https://example.org/
          predicates:
            - Path=/test
        - id: business1-provider
          uri: http://localhost:8181/
          predicates:
            - Path=/bus2/**
        - id: business2-provider
          uri: lb://business2-provider
          predicates:
            - Path=/bus2/**

• id：就是唯一值，可以随便写，确保唯一就行
• uri：就是你的请求需要转发后的地址
• predicates：断言，就是满足条件，满足就转发到uri
  注：lb://business2-provider
  在注册中心才能使用，lb是LoadBalanced的缩写，负载均衡的意思，后面是服务名

gateway详细使用说明： springcloud微服务之gateway使用