How to connect a grails app to Consul through micronaut Http Client?

Question

I have a grails 3.2.0 web profile app. I want to connect to a separate micronaut app which is running fine and is connected properly to consul locally.

Here is my micronaut controller :

@Controller("/test")
class TestController {

    @Get("/")
    def index(){
        return "Welcome to micronaut"
    }

    @Get("/test")

    Single<String> test() {
        return Single.just("Hello There")
    }
}

Here is my grails controller :

class CardClientController {

    @Autowired
    NewCardClient newCardClient

    def index() {
        def result = newCardClient.getCards()
        respond result
    }
}

NewCardClient interface :

@Client("firstmicroservice")
public interface NewCardClient {

    @Get("/test/test")
    Single<String> getCards();

}

dependencies i've added in grails app :

compile 'io.micronaut:inject-java:1.0.0.M1'
compile 'io.micronaut:discovery-client:1.0.0.M1'
compile 'io.micronaut:spring:1.0.0.M1'
runtime 'io.micronaut:runtime:1.0.0.M1'

When i hit the grails controller as /cardClient/, i am getting following error:

2019-05-03 18:20:30.333 ERROR --- [nio-8200-exec-1] i.m.retry.intercept.RecoveryInterceptor  : Type [grailsmono.NewCardClient$Intercepted] executed with error: Cannot convert publisher into target type: class io.reactivex.Flowable

java.lang.UnsupportedOperationException: Cannot convert publisher into target type: class io.reactivex.Flowable
    at io.micronaut.cache.interceptor.CacheInterceptor.interceptPublisher(CacheInterceptor.java:352)
    at io.micronaut.cache.interceptor.CacheInterceptor.intercept(CacheInterceptor.java:120)
    at io.micronaut.aop.MethodInterceptor.intercept(MethodInterceptor.java:41)
    at io.micronaut.aop.chain.InterceptorChain.proceed(InterceptorChain.java:155)
    at io.micronaut.discovery.client.$CachingCompositeDiscoveryClientDefinition$Intercepted.getInstances(Unknown Source)
    at io.micronaut.discovery.client.CachingCompositeDiscoveryClient.getInstances(CachingCompositeDiscoveryClient.java:38)
    at io.micronaut.http.client.loadbalance.DiscoveryClientRoundRobinLoadBalancer.select(DiscoveryClientRoundRobinLoadBalancer.java:58)
    at io.micronaut.http.client.DefaultHttpClient.resolveRequestURI(DefaultHttpClient.java:720)
    at io.micronaut.http.client.DefaultHttpClient.exchange(DefaultHttpClient.java:410)
    at io.micronaut.http.client.DefaultHttpClient.exchange(DefaultHttpClient.java:154)
    at io.micronaut.http.client.HttpClient.retrieve(HttpClient.java:125)
    at io.micronaut.http.client.RxHttpClient.retrieve(RxHttpClient.java:60)
    at io.micronaut.http.client.RxHttpClient.retrieve(RxHttpClient.java:33)
    at io.micronaut.http.client.interceptor.HttpClientIntroductionAdvice.intercept(HttpClientIntroductionAdvice.java:331)
    at io.micronaut.aop.MethodInterceptor.intercept(MethodInterceptor.java:41)
    at io.micronaut.aop.chain.InterceptorChain.proceed(InterceptorChain.java:155)
    at io.micronaut.retry.intercept.RecoveryInterceptor.intercept(RecoveryInterceptor.java:74)
    at io.micronaut.aop.MethodInterceptor.intercept(MethodInterceptor.java:41)
    at io.micronaut.aop.chain.InterceptorChain.proceed(InterceptorChain.java:155)
    at grailsmono.NewCardClient$Intercepted.getCards(Unknown Source)
    ...

Couldn't connect to consul and not able to debug the cause. Please help!!!

Answer 1

With the help of @JeffScottBrown, my workaround got simple just by changing the dependencies version of each as follows :

Added mavenCentral() repository as dependency :

repositories {
    mavenLocal()
    mavenCentral()
    maven { url "https://repo.grails.org/grails/core" }

}

and the required micronaut dependencies as follows :

compile 'io.micronaut:micronaut-inject-java:1.1.0'
compile 'io.micronaut:micronaut-discovery-client:1.1.0'
compile 'io.micronaut:micronaut-spring:1.1.0'
runtime 'io.micronaut:micronaut-runtime:1.1.0'