public KafkaSource ensureReady() {
		KafkaUtils.ensureReady(this.toString(), this.zkConnect, this.topic);
		return this;
	}
Ensure that the zookeeper  socket is available by polling it for up to 2 seconds and creates the topic
required by this source.

@return instance of the kafka source
@throws IllegalStateException if can not connect in 2 seconds.
spring-xd-test-fixtures/src/main/java/org/springframework/xd/test/fixtures/KafkaSource.java