IIB (IBM Integration Bus, today IBM App Connect Enterprise, ACE) is IBM's enterprise service bus / integration server: message flows built in the IIB Toolkit transform and route messages between protocols (MQ, JMS, HTTP/SOAP/REST, files, databases, SAP...). It is the successor of WebSphere Message Broker and sits between BPM and the back ends in most IBM landscapes. Integrating BAW with IIB services:
- BAW calls IIB (synchronous): IIB exposes the flow as a SOAP (SOAPInput node, WSDL) or REST API (REST API project, Swagger). In BAW import the WSDL (Web service integration) or the Swagger (REST external service), map the business objects, call it from a service flow. Put the host / port in a Server definition so that it changes per environment.
- Asynchronous through MQ / JMS: BAW's JMS / MQ outbound integration (JMS Send service on a WebSphere JMS activation spec bound to MQ) sends the request; IIB processes it and replies to a queue that BAW listens to with an undercover agent (inbound JMS integration > UCA > intermediate message event in the BPD). Use a correlation id (the instance id or a business key) in the message so that the reply reaches the right instance.
- IIB calls BAW: IIB's HTTPRequest / RESTRequest nodes call the Process REST API (POST /rest/bpm/wle/v1/process?action=start, PUT /task/{id}?action=finish, or POST /rest/bpm/wle/v1/process?action=sendMessage to raise a UCA event) with basic auth or a technical user and the CSRF token.
<!-- message that IIB sends to BAW's event queue to trigger a UCA (JMS text message) -->
<eventmsg>
<event processApp="ORD" ucaname="OrderConfirmed">OrderConfirmed</event>
<parameters><parameter><key>orderId</key><value>ORD-42</value></parameter></parameters>
</eventmsg>
Guidelines: keep canonical message formats in IIB, not in BAW; let IIB do the retries / dead-letter handling; expose only coarse-grained operations to BAW (one call per business step); on CP4BA the same applies with App Connect (containers) - REST and Kafka replace most MQ links.
References