public java.lang.String getDynamicConfigInputTopic() {
      java.lang.Object ref = dynamicConfigInputTopic_;
      if (!(ref instanceof java.lang.String)) {
        com.google.protobuf.ByteString bs = (com.google.protobuf.ByteString) ref;
        java.lang.String s = bs.toStringUtf8();
        dynamicConfigInputTopic_ = s;
        return s;
      } else {
        return (java.lang.String) ref;
      }
    }
<pre>
Optional. By setting the configuration_input_topic, processor will
subscribe to given topic, only pub/sub topic is supported now. Example
channel:
//pubsub.googleapis.com/projects/visionai-testing-stable/topics/test-topic
message schema should be:
message Message {
// The ID of the stream that associates with the application instance.
string stream_id = 1;
// The target fps. By default, the custom processor will *not* send any
data to the Vertex Prediction container. Note that once the
dynamic_config_input_topic is set, max_prediction_fps will not work and be
preceded by the fps set inside the topic.
int32 fps = 2;
}
</pre>

<code>
optional string dynamic_config_input_topic = 6 [(.google.api.field_behavior) = OPTIONAL];
</code>

@return The dynamicConfigInputTopic.
java-visionai/proto-google-cloud-visionai-v1/src/main/java/com/google/cloud/visionai/v1/VertexCustomConfig.java