
7. Content Messages
====================

AMPS provides three types of message that contain message content

-  ``publish`` messages return data from a topic as it is published, in
   order, whether the data is being published live, or is the result of
   a replay

-  ``sow`` messages return data from a SOW query. These messages return
   the state of messages that are current as of the time for the query.
   By default, the messages are returned without regard to the order in
   which the messages were published. A query can specify the order of
   the returned messages based on the data within the message by
   including the OrderBy header on the SOW query.

-  ``oof`` messages indicate that a content message no longer matches a
   subscription. These messages are sent to a client in order.

.. include:: ./content_publish.inc
.. include:: ./content-messages-sow.inc
.. include:: ./oof.inc
