WQD Message Types

There are three types of message:

The Work Queue Delta message (WQD). The WIS process sends this message.
The Work Queue Synchronization message (DSY). This contains the unique synchronization ID for the queue.
The Work Queue Invalid message (DER). This informs the subscribing application that the work queue should be closed and re-opened.

Work Queue Delta (WQD) Message

Every WQD message sent from the WIS process consists of:

a message header
message properties
the message body containing details of the Work Queue Delta. The WQD XML format is defined by the apSSOTypes.xsd schema. For more information on this schema, see the "Schemas" topic in the TIBCO iProcess™ Client (Browser) Action Processor Reference guide.

Whenever an item is added, modified or deleted from a monitored work queue, a WQD message is published by the WIS to the IAPJMS process.

Work Queue Synchronization (DSY) Message

Every DSY message consists of.

a message header
message properties
the message body containing the unique synchronization ID, which will be published when the work queue has been fully loaded and JMS publication is to begin.

A DSY message is sent once the initial queue has been built. It is published to subscribing applications so that the subscriber knows it needs to begin processing any Work Queue Deltas for the specified Work Queue Delta ID.

Work Queue Invalid (DER) Message

Every DER message consists of.

a message header
message properties
an empty message body.

The message type is an exception message sent to all applications subscribing to the work queue on which an error occurs. It tells the subscribing applications that the Work Queue Deltas for this queue are now invalid and that this work queue must be closed and re-opened.

See the TIBCO iProcess Server Objects (.NET) Programmer's Guide and the TIBCO iProcess Server Objects (Java) Programmer's Guide for more detail on Work Queue Delta publication via JMS and how it works.