The pg_amqp package provides the ability for postgres statements to directly
publish messages to an AMQP broker.

Usage:

Insert AMQP broker information (host/port/user/pass) into the
amqp.broker table.

A process starts and connects to PostgreSQL and runs:

select amqp.publish(broker_id, "amqp.direct", "foo", "message");

Upon process termination, all broker connections will be torn down.
If there is a need to disconnect from a specific broker, one can call:

select amqp.disconnect(broker_id);

which will disconnect from the broker if it is connected and do nothing
if it is already disconnected.