I'm trying to touch spring-cloud-stream, and creating a sample project of the official blog.
Implementation is totally same as the article.
@SpringBootApplication
public class SimpleConsumerApplication {
@Bean
public java.util.function.Consumer<KStream<String, String>> process() {
return input ->
input.foreach((key, value) -> {
System.out.println("Key: " + key + " Value: " + value);
});
}
}
I've selected Cloud Stream
and Spring for Apache Kafka Stream
on Spring initializr, and added ShadowJar
. Now my build.gradle
is like this.
plugins {
id 'org.springframework.boot' version '2.4.4'
id 'io.spring.dependency-management' version '1.0.11.RELEASE'
id 'java'
id 'com.github.johnrengelman.shadow' version '6.1.0'
}
group = 'com.lipsum'
version = '0.0.1-SNAPSHOT'
sourceCompatibility = '11'
jar {
manifest {
attributes('Main-Class': 'com.lipsum.kafkastream.KafkastreamApplication')
}
}
shadowJar {
archiveBaseName.set('kafka-stream-practice')
archiveClassifier.set('')
archiveVersion.set('')
}
repositories {
mavenCentral()
}
ext {
set('springCloudVersion', "2020.0.2")
}
dependencies {
implementation 'org.apache.kafka:kafka-streams'
implementation 'org.springframework.cloud:spring-cloud-stream'
implementation 'org.springframework.cloud:spring-cloud-stream-binder-kafka-streams'
testImplementation 'org.springframework.boot:spring-boot-starter-test'
}
dependencyManagement {
imports {
mavenBom "org.springframework.cloud:spring-cloud-dependencies:${springCloudVersion}"
}
}
test {
useJUnitPlatform()
}
I execute the uber jar, but springboot application fails to recognize the bean.
$ java -jar kafka-stream-practice.jar --spring.cloud.stream.bindings.process-in-0.destination=kafka-stream-practice
...
22:47:21.162 [main] ERROR org.springframework.boot.SpringApplication - Application run failed
org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'kafkaStreamsFunctionProcessorInvoker' defined in class path resource [org/springframework/cloud/stream/binder/kafka/streams/function/KafkaStreamsFunctionAutoConfiguration.class]: Unsatisfied dependency expressed through method 'kafkaStreamsFunctionProcessorInvoker' parameter 1; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'org.springframework.cloud.stream.binder.kafka.streams.KafkaStreamsFunctionProcessor' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {}
Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'org.springframework.cloud.stream.binder.kafka.streams.KafkaStreamsFunctionProcessor' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {}
I don't think the implementation has any problems. Do I miss some dependencies?