title: spring-cloud-stream-binder-kafka-streams does not consume messages from kafka
body: <p>I am trying to consume messages from a topic in Kafka via a simple Spring boot application via the spring-cloud-stream-binder-kafka-streams library.</p>
  
  <p>I am following the documentation here - <a href="https://github.com/spring-cloud/spring-cloud-stream-binder-kafka/blob/master/docs/src/main/asciidoc/kafka-streams.adoc" rel="nofollow noreferrer">https://github.com/spring-cloud/spring-cloud-stream-binder-kafka/blob/master/docs/src/main/asciidoc/kafka-streams.adoc</a></p>
  
  <p>My code is as below:
      package co.zip.poc.springbootkafkakotlin</p>
  
  <pre><code>import org.springframework.boot.autoconfigure.SpringBootApplication
  import org.springframework.boot.runApplication
  import org.apache.kafka.streams.kstream.KStream
  import org.springframework.context.annotation.Bean
  import java.util.function.Consumer
  
  
  @SpringBootApplication
  class SpringBootKafkaConsumer {
  
    @Bean
    fun process(): Consumer&lt;KStream&lt;Any, Any&gt;&gt; {
      println("=======================&gt; Creating a consumer for reading stuff&lt;=====================")
      return Consumer { input -&gt; input.foreach { key, value -&gt;
        println("============key = $key")
        println("===========value = $value")
      }}
    }
  }
  
  fun main(args: Array&lt;String&gt;) {
    runApplication&lt;SpringBootKafkaConsumer&gt;(*args)
  }
  </code></pre>
  
  <p>application.yml</p>
  
  <pre><code>spring:
    application:
      name: customer-balance
    cloud:
      stream:
        kafka:
          streams:
            binder:
              configuration:
                application:
                  id: customer-balance
        bindings:
          process_in:
            destination: "dbserver1.inventory.customers"
  
  logging:
    level:
      org.springframework.kafka.config: trace
  </code></pre>
  
  <p>I have my local kafka running on port 9092. I am able to consume messages via the kafka console consumer - </p>
  
  <pre><code>kafka-console-consumer.sh \
      --bootstrap-server localhost:9092 \
      --from-beginning \
      --property print.key=true \
      --topic dbserver1.inventory.customers
  </code></pre>
  
  <p>The above produces 4 messages on the console. But when I run the spring boot app, I don't get anything printed for the key = .. and value = print messages. </p>
  
  <p>What am I doing wrong?</p>