WebSphere Partner Gateway processes the business documents so that it can route them to the business partners in the business protocol that trading partners are expecting. The Business Processing Engine (BPE), the core of the Document Manager component, is responsible for this processing. The BPE processes the documents by executing a series of workflows in sequence: fixed inbound workflow, variable workflow, and fixed outbound workflow. Each workflow consists of a series of steps. The BPE executes the steps in sequence. User exits allow user-defined processes to be plugged into each of the workflows.
Fixed inbound workflow consists of the standard set of processing steps done to all documents coming into the Document Manager from a receiver. The workflow is fixed because the number and type of steps are always the same. Through user exits, however, you can provide customized handlers for processing the following steps: protocol unpackaging and protocol processing. The last step of fixed inbound workflow performs trading partner connection lookup, which determines the variable workflow that executes for this business document.
All messages that come into WebSphere Partner Gateway are packaged according the specification of a specific business protocol. For example, a RosettaNet document is packaged according to the RosettaNet Implementation Framework (RNIF) specification. During protocol unpackaging, the message is unpackaged so that it can be further processed. This process can include decryption, decompression, signature verification, extraction of routing information, user authentication, or business document parts extraction. WebSphere Partner Gateway provides handlers for RNIF, AS2, Backend Integration, and NONE packaging. If handlers for other packaging types are necessary, they can be developed as user exits.
Protocol processing involves determining protocol-specific information, which might include parsing the message to determine routing information (such as the sender ID and the receiver ID), protocol information (the business protocol and version, such as RosettaNet Partner Interface Processes (PIPs) version V02.02), and Document Flow Process information (such as 3A4 version V02.02). WebSphere Partner Gateway provides processing for XML, RosettaNet, and EDI protocols. Processing for other protocols such as CSV (comma-separated value), can be provided through a user exit.
If user exits are used to set up new packaging types or new protocol types, new packaging or new protocol information must also be set up in the Community Console. See the Hub Configuration Guide for more information.
As mentioned above, the last step of fixed inbound workflow determines which variable workflow executes for this business document. The business-protocol-specific processing in the BPE takes place in Variable Workflow. Variable workflow consists of a configured sequence of steps, which is also called an action. Actions are specified in the Community Console as part of the process of creating Participant Connections. WebSphere Partner Gateway ships with seventeen pre-defined actions. You can use user exits to create new actions either by developing an entirely new set of steps placed into a new sequence or by copying an existing action and modifying it either by substituting a user-defined step for a pre-existing one or by inserting a user-defined stop into an existing sequence.
Actions consist of sequences of steps. User exits can be used to create those steps. Typically, steps include the following types:
Once steps have been defined, the sequence in which they are to be executed must be specified in actions. For example, if the defined steps are validation and transformation, they can be sequenced into an action consisting only of validation, another of validation followed by transformation, and a third of validation followed by transformation followed by validation of the transformed document. Sequences of steps are linked together as actions in the Community Console. See the Hub Configuration Guide for more information.
After a document has been processed by the appropriate variable workflow, it must be packaged for transmission to its destination. WebSphere Partner Gateway provides handlers for RNIF, Backend Integration, AS, and NONE packaging, and for cXML and SOAP protocols. if other packaging handlers are required, they can be developed as user exit steps. Typically these steps will take care of one or more of the following processes:
Once the business document is packaged, it is picked up by Delivery Manager. Delivery Manager then invokes the configured sender to deliver the business document to the trading partner.