Advanced Queuing - Oracle

Figure 17–3 HTTP Advanced Queuing Propagation
Oracle9i
Server
Source
Database
Job queue
process
AQ Queue
Using HTTP and HTTPS for Advanced Queuing Propagation
Web
Server
AQ
Servlet
Destination
Database
AQ Queue
Oracle9i
Server
Since HTTP propagation is different from Net Services in only the transport, most of
the setup is the same as for Net Services propagation. The additional steps and
differences are outlined in the following section.
Setting Up for HTTP Propagation (and the Differences from Net Services
Propagation)
1. The dblink at the source database must be created differently. The connect
string should specify the protocol as HTTP and specify the host and port of the
Web server running the AQ servlet. The username and password of the dblink
will be used for authentication with the Web server/servlet runner.
2. An AQ servlet that connects to the destination database should be deployed.
3. The source database must be enabled for running Java and XML.
The rest of the steps for propagation remain the same. The administrator must use
dbms_aqadm.schedule_propagation to start propagation. Propagation can be
disabled with the dbms_aqadm.disable_propagation_schedule and re-enabled
using dbms_aqadm.enable_propagation_schedule. The background processes, the
job queue processes propagate the messages to the destination database.The job_
queue_processes parameters must be at least 2 for propagation to take place.
Any application can be easily set up to use AQ HTTP propagation without any
change to the existing code, by following steps 1-3. Similarly an application using
AQ http propagation can easily switch back to Net Services propagation just by
re-creating the dblink with a Net Services connection string, without any other
changes.
Setting Up for AQ propagation over HTTP
1. The source database must be created for running Java and XML.
Internet Access to Advanced Queuing 17-63