SpringCloud Gateway 启动报错问题解决

详细错误信息如下:

org.springframework.context.ApplicationContextException: Unable to start web server; nested exception is org.springframework.context.ApplicationContextException: Unable to start ServletWebServerApplicationContext due to missing ServletWebServerFactory bean.
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.onRefresh(ServletWebServerApplicationContext.java:156) ~[spring-boot-2.2.6.RELEASE.jar:2.2.6.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:544) ~[spring-context-5.2.5.RELEASE.jar:5.2.5.RELEASE]
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:141) ~[spring-boot-2.2.6.RELEASE.jar:2.2.6.RELEASE]
	at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:747) [spring-boot-2.2.6.RELEASE.jar:2.2.6.RELEASE]
	at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:397) [spring-boot-2.2.6.RELEASE.jar:2.2.6.RELEASE]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:315) [spring-boot-2.2.6.RELEASE.jar:2.2.6.RELEASE]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1226) [spring-boot-2.2.6.RELEASE.jar:2.2.6.RELEASE]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1215) [spring-boot-2.2.6.RELEASE.jar:2.2.6.RELEASE]
	at com.yc.gateway.YcGateWayApplication.main(YcGateWayApplication.java:17) [classes/:na]
Caused by: org.springframework.context.ApplicationContextException: Unable to start ServletWebServerApplicationContext due to missing ServletWebServerFactory bean.
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.getWebServerFactory(ServletWebServerApplicationContext.java:203) ~[spring-boot-2.2.6.RELEASE.jar:2.2.6.RELEASE]
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.createWebServer(ServletWebServerApplicationContext.java:179) ~[spring-boot-2.2.6.RELEASE.jar:2.2.6.RELEASE]
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.onRefresh(ServletWebServerApplicationContext.java:153) ~[spring-boot-2.2.6.RELEASE.jar:2.2.6.RELEASE]
	... 8 common frames omitted

核心错误信息如下:

Unable to start ServletWebServerApplicationContext due to missing ServletWebServerFactory bean

经过一系列问题排查，最终锁定是包的问题，出问题的Maven依赖如下:

<dependency>
         <groupId>com.yc.framework</groupId>
         <artifactId>yc-common-core</artifactId>
     </dependency>

报错原因是因为该依赖中引入mvc包，而这个mvc包与SpringBoot本身依赖产生了冲突。

解决方案如下(排除mvc依赖就能解决):

<dependency>
      <groupId>com.yc.framework</groupId>
      <artifactId>yc-common-core</artifactId>
      <exclusions>
          <exclusion>
              <groupId>org.springframework</groupId>
              <artifactId>spring-webmvc</artifactId>
          </exclusion>
      </exclusions>
  </dependency>