New feature for using Universal Messaging to connect Apama components in 5.2
Universal Messaging (UM) is Software AG's middleware service that delivers data across different networks. It provides messaging functionality without the use of a web server or modifications to firewall policy.
Previous Apama releases provided access to UM only through the correlator-integrated adapter for JMS. With Apama 5.2, there is support for Apama applications to directly use UM to transport events between Apama components. This can make deployments more flexible and can simplify configuration.
In an Apama application, correlators and adapters can connect to UM realms or clusters. A correlator or adapter connected to a UM realm or cluster uses UM as a message bus for sending Apama events between Apama components. Connecting a correlator or adapter to UM is an alternative to
Defining connections between an adapter and particular correlators in the
<apama> element of an adapter configuration file
Specifying a connection between two correlators by executing the
engine_connect correlator utility
Using UM can simplify an Apama application configuration. Instead of specifying many point-to-point connections you specify only the address (or addresses) of the UM realm or cluster. Apama components connected to the same UM realm use UM channels to send and receive events. (UM channels are similar to JMS topics.)
When an Apama application uses UM a correlator can be configured to automatically connect to the required UM channels. There is no need to explicitly connect UM channels to individual correlators. A correlator automatically receives events on UM channels that monitors subscribe to and automatically sends events to UM channels.
You can use UM only to send and receive events. You cannot use UM for EPL injections, delete requests, engine send, receive, watch or inspection utilities, or engine_management -r requests.
Only UM channels can be used with Apama. UM queues and datagroups are not supported in this Apama release.
In Apama Studio, you can add UM support to a project. After you do that, you can choose whether to specify UM messaging in correlator launch configurations and in adapter configurations.
In an IAF adapter configuration file, the new enabled attribute in an <apama> element and in the new <universal-messaging> element indicates whether the adapter uses UM. The default behavior is that an adapter does not use UM. To configure an adapter to use UM, set enabled to true in the <universal-messaging> element. Also, set enabled to false in the <apama> element, if there is one. This indicates that the configuration specified in the <apama> element should be ignored and the configuration specified in the <universal-messaging> element should be used.
When you are upgrading an application to use Apama 5.2 and you are configuring it to use UM keep in mind that events must be sent to named channels. You might need to add channel specifications to events. For adapters, you can use the
transportChannel,
presetChannel, and
defaultChannel attributes to set channel names. If you do not specify values for any of these attributes, but you use Apama Studio to add UM support to your project then a default channel name will be in place for adapters that use UM. If you do not use Apama Studio then you must at least specify a value for the
defaultChannel attribute in IAF adapter configurations. For details, see
Event file format and
Configuring adapters to use UM.
Apama 5.2 supports only the 9.7 release of Universal Messaging. The
Supported Platforms document for version 5.2 in the
Apama documentation lists supported releases for all Apama components.
Details for using UM in an Apama application are in
Using Universal Messaging in Apama Applications .
