Transactions, security, and connection properties for an IMS system

IBM BPM, V8.0.1, All platforms > Authoring services in Integration Designer > Services and service-related functions > Access external services with adapters > Configure and using adapters > IBM Resource Adapters > WOLA resource adapter
Transactions, security, and connection properties for an IMS system

Using WOLA, business processes and services on IBM Process Server for z/OS can call IMS programs.

IMS outbound calling

For IMS (similar to CICS), you can call IMS transactions that use the WOLA link server using the native WOLA APIs (Host Service and Receive Request). Using the IMS Open Transaction Manager Access (OTMA) interface through WOLA, you can also call IMS transactions and drive them in IMS message processing regions or fast-path dependent regions. When you target IMS transactions using OTMA, you do not specify a register name in the connection properties.
Important: WOLA does not support local or global transactions when invoking applications in IMS. All requests sent to IMS applications over WOLA run with Commit Mode 1 and Send-then-Commit. With this, OTMA defers the commit till the response message is sent.

IMS security propagation

For security propagation and assertion between the Process Server for z/OS and an IMS system, use WOLA over the OTMA interface. The Process Server for z/OS must be configured to run with the SyncToThread option enabled. Also, the IMS OTMA parameter OTMASE=FULL must be set. With these settings, the user ID under which the Process Server for z/OS application runs is propagated and asserted in the IMS message processing or fast-path dependent region where the transaction is dispatched. The security propagation and assertion between the Process Server for z/OS and the IMS system does not apply to IMS batch message processing regions.
In Process Server for z/OS, you may choose to use the security credentials that are already set on the thread, which by default is the user ID that is running the server, or you can set the credentials using a JAAS alias.

IMS connection properties

When creating the WOLA import and service, you must define the connection properties for the target IMS system.
In the New External Service wizard, on the Security and Configuration Properties page, specify the JNDI name of the connection factory defined on Process Server for z/OS or specify the connection properties for the IMS server in the binding.
If you choose to specify the connection properties, then the managed connection factory is created during deployment with the specified properties.
Important: Define the connection factory on the server for easy changes by the administrator. You can share or reuse the same connection factory among many external services.
When targeting an IMS transaction via OTMA then you must set the appropriate OTMA properties in the connection factory. In the binding, these are found under the IMS OTMA connection properties area in the Security and Configuration Properties page, where you must select IMS OTMA connection properties and select Use OTMA to set OTMA properties to call IMS transactions instead of using the native WOLA APIs.
To communicate with a COBOL, PL/I, C, or C++ program on a IMS system, you must set the following properties:

Group ID - Specifies the target IMS OTMA name. This value must be a valid OTMA XCF group name.
Server name - Specifies the target IMS OTMA server name.
Sync level - Specifies the OTMA sync level. For IMS to commit work for a processed transaction after sending the response to the application server without receiving a positive acknowledgment that the response was accepted, set the sync level to None. For IMS to commit the transaction only after receiving a positive acknowledgment, select Confirm as the sync level. If the acknowledgment is negative, the inflight work is rolled back.
Request prefix style - Specifies the prefix style for inbound messages to the IMS server.
Response prefix style - Specifies the prefix style for outbound messages from the IMS server.

The value of the properties Request prefix style and Response prefix style should be LLZZ when targeting a COBOL, C, or C++ program. For a PL/I program, the value can be set to either LLZZ or LLLL.
For IMS transactions, when using WOLA over OTMA, the target transaction is embedded in the inbound message. You do not need to specify the InteractionSpec properties at the operation level.