Windchill ESI services give Windchill PDMLink the capability to communicate with the EAI components via a set of JMS queues. The EAI components are responsible for monitoring a set of queues, which are written to by Windchill PDMLink. Conversely,Windchill ESI services monitor a certain complementary queue (meant to hold the results of a publication) that is written to by the Windchill EAI components.

For example, to notify the EAI software components that a new object was released from Windchill PDMLink,Windchill ESI services generate one or more response messages representing the released product information, and place them on the data response queue. The EAI software components, which listen for messages arriving on this queue, respond by creating or modifying one or more analogous objects in a distribution target such as an ERP system. Results of the distribution target update are then communicated back toWindchill ESI services using an RPC via another queue whichWindchill ESI services are listening on.

The RPC interface uses SOAP-formatted Extensible Markup Language (XML) documents to exchange information. An RPC request is a small XML document containing the RPC parameters. It is typically constructed by the EAI software components that pass it to Windchill ESI services over a JMS queue. Info*Engine uses the information in the JMS queue entry to resolve the RPC request into an Info*Engine task, which Info*Engine then executes. The task output is converted into a SOAP-formatted XML document with the requested information.

Windchill ESI services provide the following types of RPCs:

As for query RPCs, these areInfo*Engine tasks thatWindchill ESI services may invoke directly as needed, whenever a user initiates the release of a business object such as a WTPart. The Info*Engine tasks in GetPart.xml, GetBOM.xml and GetECN.xml are examples of such RPCs. A single XML schema based on the XSD standard, describes the structure of the response document for all of the query RPCs provided byWindchill ESI Services. See the section titled "Windchill ESI Query RPC Response Schema" in the Windchill Enterprise Systems Integration Open Application Programming Interface Guide for more information on the response schema.

Transaction management RPCs are Remote Procedure Calls that are constructed by the EAI software components and passed to Windchill over a JMS queue, as described earlier in this section. PostResult and PostEvent are examples of transaction management RPCs.

For more information on the XML schema, see the relevant topics in this help. See the Windchill Enterprise Systems Integration Open Application Programming Interface Guide and XML Schemas for detailed descriptions of schemas used by theWindchill ESI services and EAI components respectively.