title: Spring Cloud Stream - Functional Supplier is not polling
body: <p>In Spring Cloud Stream, I used the functional model and created a Supplier to generateEvents.  As per the <a href="https://docs.spring.io/spring-cloud-stream/docs/3.1.3/reference/html/spring-cloud-stream.html#_suppliers_sources" rel="nofollow noreferrer">documentation</a>, I expect that this supplier will get invoked on a scheduled basis, but that's not happening. It gets invoked once upon bean creation, and never again.  I'd appreciate any help in figuring out why.</p>
  <p>EventSource.java (Supplier):</p>
  <pre><code>@Component
  @Slf4j
  public class EventSource {
  
      @Bean
      public Supplier&lt;String&gt; generateEvents() {
          log.debug(&quot;creating an event to publish to Kafka&quot;);
          return () -&gt; &quot;Hi I'm an event&quot;;
      }
  
  }
  </code></pre>
  <p>application.yml:</p>
  <pre><code>spring:
    cloud:
      function:
        definition: generateEvents
      stream:
        bindings:
          generateEvents-out-0:
            destination: eventsTopic
  </code></pre>
  <p>I know I'm connecting to Kafka, because the topic <code>eventsTopic</code> gets created upon startup.  The Cloud Stream app stays up, but doesn't do anything.</p>