啟動spring cloud中的網關，報錯：
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APPLICATION FAILED TO START
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Description:
The bean 'httpClient', defined in class path resource [org/springframework/cloud/openfeign/ribbon/HttpClientFeignLoadBalancedConfiguration$HttpClientFeignConfiguration.class], could not be registered. A bean with that name has already been defined in class path resource [org/springframework/cloud/gateway/config/GatewayAutoConfiguration$NettyConfiguration.class] and overriding is disabled.
Action:
Consider renaming one of the beans or enabling overriding by setting spring.main.allow-bean-definition-overriding=true
我用的網關是gateway，內部調用是用的openfeign，這兩者會沖突，上面報錯信息顯示httpClient在兩者都有聲明，要把兩者中一者去掉，於是看了下兩個類的源碼，可以把feign上的httpClient禁用了。
org/springframework/cloud/openfeign/ribbon/HttpClientFeignLoadBalancedConfiguration$HttpClientFeignConfiguration.class的代碼中有如下圖：
上面可以看出，可以配置：
feign.httpclient.enabled=false
或者
feign.compression.response.enabled=true
來禁用openfeign的httpClient類定義
也可以直接用配置：spring.main.allow-bean-definition-overriding=true