In April 2011, IBM announced CICS TS V4.2, which provides many enhancements to EP. Due to the increased interest in EP that CICS TS V4.1 sparked, these enhancements were almost entirely driven by customer requirements; the development team has worked closely with beta customers to ensure what has been delivered is what they need. This article looks at some requirements for EP and the corresponding features of CICS TS V4.2.
Separate EP Adapters
In CICS TS V4.1, every event binding had an EP adapter specification containing the format and transport that should be used to emit the events it described. Figure 2 shows several event bindings (purple) in a bundle (blue), each with their own EP adapter specification (orange).
As customers started to use EP in CICS TS V4.1, we saw that, typically, all events from CICS would be sent to a single event consumer. Despite this, they wouldn’t use a single event binding; rather they would have many event bindings so events could be managed in logical groups. As a result, information in the EP adapter specification was being duplicated in each event binding. This led to concern that, if the event consumer changed, there would be considerable work needed to change the EP adapter specification in every binding.
The solution CICS TS V4.2 provides is to let EP adapter specifications be defined as a separate bundle resource, which can then be referenced from multiple event bindings. EP adapters can be referenced by event bindings across bundles, and there can be multiple EP adapters per bundle (see Figure 3). Once installed, EP adapters can be inquired upon just like any other CICS resource. Separate EP adapter specifications let you share, rather than duplicate, the information in them, so now a change requires updating just one resource.
Event Binding Search
Non-invasive capture of events from applications will, inherently, introduce affinities between event bindings and programs. Customers were concerned that if they had many events defined to CICS, it would be difficult to determine whether an application change could unintentionally cause extra events to be emitted or somehow break existing events.
CICS TS V4.2, with CICS Explorer V1.1, provides EP search, a feature that addresses this issue. EP search lets a user search for event bindings that may be affected by an application change. EP search can be performed against event bindings, both in the CICS Explorer workspace and in connected CICS regions. To use EP search, the user types the name of the application asset being changed (e.g., CICS resource, program, language structure, variable field, etc.) into the search dialog and CICS Explorer will find all event bindings that may be affected (see Figure 4).