spring-projects/spring-xd — pull request #1057 by garyrussell (2014-07-11 20:44:17+00:00)
Title: Restore PubSub Producer Exchange Declaration

XD-1786 incorrectly removed the declaration of the exchange
on the producer side.

Although tap producers are not created before consumers, a
named 'topic:' would publish to a non-existent exchange
until a consumer is bound.

Spring AMQP now logs such publications as an ERROR.