Unable to use reactive WebClient without spring-boot-starter-reactor-netty

This is probably more of a documentation issue but when developing a reactive application on Tomcat (and probably others) and you exclude starter-reactor-netty like this

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-webflux</artifactId>
    <exclusions>
        <exclusion>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-reactor-netty</artifactId>
        </exclusion>
    </exclusions>
</dependency>
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-tomcat</artifactId>            
</dependency>

then WebClient won’t work. The class is on the path but creating a new one with return WebClient.create("http://localhost:8080"); will fail:

Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.web.reactive.function.client.WebClient]: Factory method 'webClient' threw exception; nested exception is java.lang.NoClassDefFoundError: reactor/ipc/netty/http/client/HttpClient
	at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:182)
	at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:575)
	... 43 common frames omitted
Caused by: java.lang.NoClassDefFoundError: reactor/ipc/netty/http/client/HttpClient
	at org.springframework.http.client.reactive.ReactorClientHttpConnector.<init>(ReactorClientHttpConnector.java:47)
	at org.springframework.web.reactive.function.client.DefaultWebClientBuilder.initExchangeFunction(DefaultWebClientBuilder.java:139)
	at org.springframework.web.reactive.function.client.DefaultWebClientBuilder.build(DefaultWebClientBuilder.java:115)
	at org.springframework.web.reactive.function.client.WebClient.create(WebClient.java:173)
	at com.example.demo.NewClass$CustomConfig.webClient(NewClass.java:29)
	at com.example.demo.NewClass$CustomConfig$$EnhancerBySpringCGLIB$$7b5a2896.CGLIB$webClient$0(<generated>)
	at com.example.demo.NewClass$CustomConfig$$EnhancerBySpringCGLIB$$7b5a2896$$FastClassBySpringCGLIB$$783fa80e.invoke(<generated>)
	at org.springframework.cglib.proxy.MethodProxy.invokeSuper(MethodProxy.java:228)
	at org.springframework.context.annotation.ConfigurationClassEnhancer$BeanMethodInterceptor.intercept(ConfigurationClassEnhancer.java:359)
	at com.example.demo.NewClass$CustomConfig$$EnhancerBySpringCGLIB$$7b5a2896.webClient(<generated>)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:155)
	... 44 common frames omitted
Caused by: java.lang.ClassNotFoundException: reactor.ipc.netty.http.client.HttpClient
	at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
	at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:335)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:357)

[wilkinsona]

@dancingfrog You can set the web application type to none when creating your SpringApplication.

[madhtr]

@dancingfrog You can set the web application type to none when creating your SpringApplication.

True. But if I am creating a project intended to be used as a maven dependency in another project, the developer on the dependent project will have to do this as well.

Excluding spring-boot-starter-tomcat worked with spring boot web. But it does not work with webflux. This is not ideal IMHO.

Respectfully.