SpringCloud gateway学习之helloWorld

1、POM.xml文件：

<?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>
    <groupId>com.demo</groupId>
    <artifactId>gateway</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>gateway</name>
    <description>Demo project for Spring Boot</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.8.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
    </properties>

    <!--cloud 引来-->
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>Greenwich.SR3</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

    <dependencies>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-gateway</artifactId>
        </dependency>
    </dependencies>

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

</project>

2、Application.yml配置文件：

spring:
  cloud:
    gateway:
      routes:
        - id: app
          uri: http://www.baidu.com
          predicates:
            - Path=/app/**
          filters:
            - StripPrefix=1

3、运行：

运行程序，在浏览器中输入：http://localhost:8080/app，浏览器会自动跳转到http://www.baidu.com；

4、坑点：

(1) 最大的坑点就是版本问题，如果没有用对应版本，则运行会报错甚至运行不起来；spring-boot-starter-parent用2.0.4.RELEASE版本时，spring-cloud-dependencies要用Finchley.RELEASE；当spring-boot-starter-parent用2.1.8.RELEASE版本时，spring-cloud-dependencies要用Greenwich.SR3；

(2) spring-cloud-starter-gateway包和spring-boot-starter-web包不能并存，如果两个都依赖了，运行会报错，得删掉spring-boot-starter-web依赖后才能运行起来；