Business Process Execution Language for Web Services

In this article, we will walk through modeling a sample process using the Business Process Execution Language for Web Services.\\ !!The Loan Approval Process Example !Overview The process illustrates a customer sending a SOAP request asking for a possibility to get a loan from a financial institution.\\ The request gets processed through a sequence of logic execution or invocation of other web services\\ in order to return an appropriate reply for the customer request,\\ then the customer finds out whether the loan was approved or not. !Partners In order for the loan to get processed a customer has to initiate the loan request,\\ approver has to approve the loan and assessor helps in evaluating the risk of the requested loan.\\ Each of these three Organization Units or partners shown in the next diagram plays a role in the process.\\ To get involved into the process, a partner link has to be defined on the process level pointing to an abstract partner link type which in return defines physical port.\\ All partner links of this type can be communicated later on through this pre-defined port.\\ Both the approver and assessor have pre-defined WSDL files, defining their physical ports,\\ message formats and available web methods that can be invoked by involved partners.\\ \\ The following figure shows Loan Approval Process and Partners: |> \\ following is Partners and physical ports |> \\ The following XML fragment from WSDL of the process defines two types of partner links,\\their roles and references to port types used for communication. {{{ 1 2 3 4 5 6 7 8 9 10 11 }}} \\ !SOAP Operations Possible SOAP messages involved in the process includes:\\ - A request from the customer for a loan\\ - A call to the assessor 'check' web method\\ |> - A reply from the assessor\\ |> - A call to the approver 'approve' web method\\ |> - A reply from the approver\\ |> - A response from the process to the customer\\ !Process Flow The process itself is defined as follows\\ {{{ 1 9 10 11 13 15 17 19 20 21 22 25 28 31 32 33 34 36 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 59 61 63 64 65 70 71 73 75 76 77 78 79 80 81 82 83 84 85 86 91 92 93 94 95 96 98 99 100 101 102 }}} Visualizing the process will lead us to the following diagram:\\ |>

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