Support Spring 5 & Spring Boot 2 reactive web

[sameer-pandit]

I tried adding spring cloud eureka, to pom.xml (for reactor-netty profile)of spring-boot-sample-web-reactive, I am getting the below error in test of sample. What is the correct way to use eureka discovery service for spring boot web reactive app. Same Issue against spring boot web reactive was closed, and @bclozel suggested to add issue against spring cloud eureka.

Caused by: org.springframework.context.ApplicationContextException: Unable to start embedded container; nested exception is org.springframework.context.ApplicationContextException: Unable to start ReactiveWebApplicationContext due to missing ReactiveHttpServerFactory bean.

Below are changes made to pom.xml of spring-boot-sample-web-reactive

diff --git a/spring-boot-sample-web-reactive/pom.xml b/spring-boot-sample-web-reactive/pom.xml
index 7948b03..ce56ae7 100644
--- a/spring-boot-sample-web-reactive/pom.xml
+++ b/spring-boot-sample-web-reactive/pom.xml
@@ -12,7 +12,12 @@
        <name>Sample project for Spring Boot Web Reactive</name>
        <description>Spring Boot Web Reactive Sample</description>

-
+    <repositories>
+       <repository>
+          <id>spring-maven</id>
+          <url>http://maven.springframework.org/release</url>
+       </repository>
+    </repositories>
     <profiles>
         <profile>
             <id>tomcat</id>
@@ -23,7 +28,7 @@
                 <dependency>
                     <groupId>org.springframework.boot.experimental</groupId>
                     <artifactId>spring-boot-starter-web-reactive</artifactId>
-                </dependency>
+                </dependency>                
                                <!-- Using Reactor Netty HTTP client in tests -->
                                <dependency>
                                        <groupId>io.projectreactor.ipc</groupId>
@@ -55,6 +60,11 @@
                     <groupId>io.projectreactor.ipc</groupId>
                     <artifactId>reactor-netty</artifactId>
                 </dependency>
+                <dependency>
+                    <groupId>org.springframework.cloud</groupId>
+                    <artifactId>spring-cloud-starter-eureka</artifactId>
+                    <version>1.2.0.RELEASE</version>
+                </dependency>
             </dependencies>
         </profile>

[ryanjbaxter]

Usually you would use the Spring Cloud BOM and add the dependency

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>Camden.BUILD-SNAPSHOT</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
            <dependency>
                <groupId>org.springframework.boot.experimental</groupId>
                <artifactId>spring-boot-dependencies-web-reactive</artifactId>
                <version>0.1.0.BUILD-SNAPSHOT</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

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

However even when doing that I also see the same error. I don't believe we have started looking at supporting anything other than Spring Boot 1.4.x and 1.5.x at this point though.

[spencergibb]

👍 to what @ryanjbaxter said, we haven't started reactive support yet.

[spencergibb]

May as well use this as the placeholder. Work will be part of the Edgware release (just released Camden, Dalston targeting end of 2016).

[sameer-pandit]

I am guessing this due to some conflicting dependencies, is there some work around for now ?

[bclozel]

@sameer-pandit reactive streams is a rather different paradigm and supporting that needs quite a lot of work. I don't think there's a workaround for that.

[noorulhaq]

In case if you are still wondering how to acheive that. Then I have done some experiment that is available on github.
Read below article for more detail.
https://dzone.com/articles/functional-amp-reactive-spring-along-with-netflix

[breun]

Currently you end up with converting reactive stream types twice if you want call external services in a Spring WebFlux web application using Spring Cloud Netflix, because Hystrix only supports RxJava 1 Observable as a reactive return type:

WebClient -> Reactor type (Mono/Flux) -> convert to RxJava 1 Observable -> Hystrix command/annotation -> convert Observable back to Reactor type (Mono/Flux) -> WebFlux controller returns Reactor type

[spencergibb]

This has been supported since Finchley.RELEASE