95-843 Service Oriented Architecture                      Carnegie Mellon University

Assigned: Friday, June 8                                  Homework 4

Due: Friday, June 15, 2012, 11:59:00 PM

When you have completed this project, notify your instructor by email.
In your email, provide your machine name and your application and 
project names and any instructions that may be useful.

* In your email, state exactly what parts of this homework you have working. *

In this project you will build a BPEL process that interacts with two external
web services. One service will be provided by an organization that provides 
on-demand financial market data - see http://www.xignite.com. The second 
service will be used for currency conversion and is provided by 
http://www.webservicex.net.

This project has been adapted from the course text "Oracle SOA Suite 11g 
R1 Developer's Guide" and is found in chapter 5.

Parts one and two describe the construction of a synchronous BPEL process. Part
three asks that you add switch and flow statements to your work in part two.

Part 1. Build a simple BPEL process that interacts with an external web service.

0) In order to use the currency converter service, you will save the WSDL
   located at http://www.webservicex.net/CurrencyConvertor.asmx?WSDL to the file
   C:\OracleSOASuite11gDevelopersGuide\Chapter05\Currency.wsdl.

1) In order to use the financial service, you will need to register at http://www.xignite.com.

2) The WSDL that you will need is found here:
   http://www.xignite.com/xQuotes.asmx?WSDL

3) Save the Xignite WSDL file to the virtual machine's C: drive under the name
   C:\OracleSOASuite11gDevelopersGuide\Chapter05\XigniteQuotes.wsdl.

4) We will use the following XSD file from the course text. Save it to
   C:\OracleSOASuite11gDevelopersGuide\Chapter05\StockService.xsd. You
   may copy and paste this xsd file from this document.
   
<?xml version="1.0" encoding="windows-1252"?>
<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema"
            xmlns="http://xmlns.packtpub.com/xml/StockService"
            targetNamespace="http://xmlns.packtpub.com/xml/StockService"
            elementFormDefault="qualified" >
	<xsd:element name="getQuote"           type="tGetQuote"/>
        <xsd:element name="getQuoteResponse"   type="tGetQuoteResponse"/>
        <xsd:element name="placeOrder"         type="tPlaceOrder"/>
        <xsd:element name="placeOrderResponse" type="tPlaceOrderResponse"/>
        <xsd:complexType name="tGetQuote">
                <xsd:sequence>
                        <xsd:element name="stockSymbol" type="xsd:string"/>
                        <xsd:element name="currency"    type="xsd:string"/>
                </xsd:sequence>
        </xsd:complexType>
        <xsd:complexType name="tGetQuoteResponse">
                <xsd:sequence>
                        <xsd:element name="stockSymbol" type="xsd:string"/>
                        <xsd:element name="currency"    type="xsd:string"/>
                        <xsd:element name="amount"      type="xsd:decimal"/>
                </xsd:sequence>
        </xsd:complexType>
        <xsd:complexType name="tPlaceOrder">
                <xsd:sequence>
                        <xsd:element name="stockSymbol" type="xsd:string"/>
                        <xsd:element name="currency"    type="xsd:string"/>
                        <xsd:element name="buySell"     type="xsd:string"/>
                        <xsd:element name="quantity"    type="xsd:integer"/>
                        <xsd:element name="bidPrice"    type="xsd:decimal"/>
                </xsd:sequence>
        </xsd:complexType>
        <xsd:complexType name="tPlaceOrderResponse">
                <xsd:sequence>
                        <xsd:element name="stockSymbol" type="xsd:string"/>
                        <xsd:element name="currency"    type="xsd:string"/>
                        <xsd:element name="buySell"     type="xsd:string"/>
                        <xsd:element name="quantity"    type="xsd:integer"/>
                        <xsd:element name="actualPrice" type="xsd:decimal"/>
                </xsd:sequence>
        </xsd:complexType>
</xsd:schema>

5) Our web service, the one we are writing in BPEL, will use the XSD above. The 
   web service from Xignite is defined in the Xignite WSDL. We will need to 
   build a mapping from our service vocabulary to the external service's vocabulary.

6) In JDeveloper, create a new SOA Application. Its name is 
   StockQuoteApplication<YourAndrewID>.

   The Project name is StockQuoteProject<YourAndrewID>. Create an empty composite.

7) Drag a BPEL component onto the composite. Its name is StockQuoteBPEL. It will
   be a SOAP based synchronous service and we want the input to this BPEL process and
   the output from this BPEL process to be defined based upon the vocabulary 
   expressed in the XSD above. Use the magnifying glass icon to the right of the 
   input and output text boxes to browse the file system. The Type Chooser has
   an Input Schema button on the top right. On the Input Schema File wizard use 
   the magnifying glass icon again to browse to the StockService.xsd. We can
   now select from this vocabulary.  Use the GetQuote for the input to the
   BPEL process and use the GetQuoteResponse for the output.

8) Right click and add a partner link to the right on the BPEL process (not the composite).
   Its name will be xigniteservice and it will be based on the wsdl that we retrieved from
   Xignite.com. Use the magnifying glass icon to browse for the wsdl. Choose
   OK to prompts asking if it's OK to extend or move the file. Choose the 
   partner role as XigniteQuotesSOAP role. Leave the My Role selection as 
   unspecified (this is a synchronous call and only one interface is required.)

9) Place an invoke activity onto your BPEL diagram. Name the invoke "CallXignite".
   Connect the invoke to the partner link by clicking and dragging an arrow. From the 
   wizard, choose the GetSingleQuote operation. We want to name the input and output variables of
   this service. Use the green plus sign on the wizard to name the variables
   XigniteInput and XigniteOutput respectively. Note that the types of these variables
   are already defined in the WSDL.

10) The inputs and the outputs of the BPEL process are defined with a different
    vocabulary than the inputs and outputs of the Xignite service. Use the assign
    activity to perform a mapping from the BPEL variables to the Xignite variables.
    Drag two assign activities onto the BPEL diagram - one before the invoke and 
    one after. Name the first "prepareToCall" and name the second "gatherResponse". 
    This is done by double clicking the assign activity and choosing the General tab.
    Use the assign wizard to connect the correct BPEL input to the correct Xignite
    input. Note that two different namespaces are being used. We are mapping the 
    name stockSymbol to the name symbol. In the GatherResponse assign we want to
    map the outputs of the Xignite service to the outputs of our BPEL process.
    Map the name "symbol" to "stockSymbol" and "last" to "amount". To add the 
    currency string 'USD' to the output drag the function symbol onto the currency 
    output variable. Enter the string constant 'USD' in the expression box. Include 
    the single quotes.

11) Deploy the StockQuoteProject to the application server. This is done by right
    clicking the project, choosing deploy and specifying an existing connection.

12) Visit the Enterprise Manager web application. This is located at 
    http://localhost:7001/em. Log on with your username and password.

13) When testing your new project, you may receive an error message embedded within
    the response from Xignite. It may be rejecting this request because it does
    not have the requesting machine's IP address as a registered address. If this 
    is the case, then visit xiginte and register the IP address. The best way to
    learn what this address is is to examine the error responses from xignite. Use
    the trace feature of the Enterprise Manager to do this. Check the payload of
    the callXignite invoke. The trace manager is executed by clicking the 
    instance ID.

Part 2. Access a web service that performs currency conversion.

1) Create a new partner link and name it CurrencyConvertor. Associate the new
   partner link with the currency convertor wsdl. This will be a synchronous
   SOAP based web service with My Role set to not specified. 

2) Create a new Invoke activity that uses the new partner to convert from USD
   to the currency specified in the original request from the originating client.
   Perform this invoke before returning the converted price to the client.

3) Add two assign activities. One just prior to and another just after the call 
   to the currency convertor. The first will prepare to call the currency convertor
   and the second will be used to compute a stock price based on the value returned
   by the currency convertor and the value returned by Xignite.

   To create the second assign activity, drag the function symbol to the 
   output variable. (This is the output variable for the entire BPEL process.)
   This will open up an expression builder. You may then build XPath expressions
   and use multiplication to compute the final result.  

4) When deploying the new service be sure to select the "Overwrite" check box 
   so that you overwrite the previous composite on the administration server.
   Test the new service by looking up IBM's stock price in Canadian currency 
   "CAD'.

Part 3. Add a test condition to your process so that the currency conversion service
   is not used when the visitor requests currency in US Dollars. Xignite already returns
   the stock price in US dollars, so, in this case, the conversion step is not needed. 
   If currency conversion is required then, of course, both services need to be called. 
   At a minimum, call these services sequentially. For full credit, call them in parallel.