Dynamic Routing in OSB 12C

Dynamic Routing in OSB cab be used when the BusinessService endpoint required to be determine at runtime in message flow.

Consider a scenario where OSB has to route the incoming requests to 2 different services based on the CustomerType element value sent in the payload. So create a XQuery resource with the following contents. Observe that we are using the absolute path of business service in configuration as required by dynamic routing.

Following is the XML schema that we use:>> Customer.xsd

<?xml version="1.0" encoding="windows-1252" ?>

<xsd:schema targetNamespace="http://xmlns.oracle.com/schema/Customer" xmlns:xsd="http://www.w3.org/2001/XMLSchema"

            xmlns:ns1="http://xmlns.oracle.com/schema/Customer">

  <xsd:complexType name="Customer">

    <xsd:sequence>

      <xsd:element name="CustomerId" type="xsd:string"/>

      <xsd:element name="FirstName" type="xsd:string"/>

      <xsd:element name="LastName" type="xsd:string"/>

      <xsd:element name="MiddleName" minOccurs="0" type="xsd:string"/>

      <xsd:element name="CustomerType" type="xsd:string"/>

      <xsd:element name="Email" minOccurs="0" type="xsd:string"/>

      <xsd:element name="Mobile" minOccurs="0" type="xsd:string"/>

    </xsd:sequence>

  </xsd:complexType>

  <xsd:complexType name="StatusMsg">

    <xsd:sequence>

      <xsd:element name="CustomerId" type="xsd:string"/>

      <xsd:element name="Response" type="xsd:string"/>

      <xsd:element name="ErrorCode" type="xsd:string" minOccurs="0"/>

      <xsd:element name="ErrorMessage" type="xsd:string"/>

    </xsd:sequence>

  </xsd:complexType>

  <xsd:element name="StatusMsg" type="ns1:StatusMsg"/>

  <xsd:element name="Customer" type="ns1:Customer" />

</xsd:schema>

x

Following is the WSDL that we will use for the proxy service >> CustomerService.wsdl


<wsdl:definitions name="CustomerService" targetNamespace="http://xmlns.oracle.com/wsdl/CustomerService"

                  xmlns:wsdl="http://schemas.xmlsoap.org/wsdl/" xmlns:ns1="http://xmlns.oracle.com/schema/Customer"

                  xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:tns="http://xmlns.oracle.com/wsdl/CustomerService"

                  xmlns:soap="http://schemas.xmlsoap.org/wsdl/soap/">

  <wsdl:types>

    <xsd:schema>

      <xsd:import namespace="http://xmlns.oracle.com/schema/Customer" schemaLocation="Customer.xsd"/>

    </xsd:schema>

  </wsdl:types>

  <wsdl:message name="CustomerCreate">

    <wsdl:part name="parameters" element="ns1:Customer"/>

  </wsdl:message>

  <wsdl:message name="CustomerCreateResponse">

    <wsdl:part name="parameters" element="ns1:StatusMsg"/>

  </wsdl:message>

  <wsdl:portType name="CustomerServicePort">

    <wsdl:operation name="CustomerCreate">

      <wsdl:input message="tns:CustomerCreate"/>

      <wsdl:output message="tns:CustomerCreateResponse"/>

    </wsdl:operation>

  </wsdl:portType>

  <wsdl:binding name="CustomerServiceBinding" type="tns:CustomerServicePort">

    <soap:binding style="document" transport="http://schemas.xmlsoap.org/soap/http"/>

    <wsdl:operation name="CustomerCreate">

      <soap:operation soapAction="CustomerCreate"/>

      <wsdl:input>

        <soap:body use="literal"/>

      </wsdl:input>

      <wsdl:output>

        <soap:body use="literal"/>

      </wsdl:output>

    </wsdl:operation>

  </wsdl:binding>

</wsdl:definitions>

OSB project configuration:

Create the required resources a proxy service based on the above WSDL, 2 business services and a XQuery resource with the contents shown above.

Create the message flow as shown below.

First Implementation: 

The assign activity stores the value of customer type element in the payload in ‘varType’ variable using the xpath expression $body/cus:Customer/CustomerType/text().

For the dynamic routing the expression should resolve to the following XML snippet. The attribute isProxy has to be set to ‘true’ if routing the request to proxy service or ‘false’ if routing the request to business service. Operation name is optional as business service might  not be WSDL service always.

<ctx:route>

<ctx:service isProxy='false'>absolute path of business service</ctx:service>

<ctx:operation>operation name</ctx:operation>

</ctx:route>

So for our case use the XML contents as shown in the below screenshot along with the XPath expressions to get the required values.

Second implementation:

you can write some thing like with help of XQEURY file:

xquery version "1.0" encoding "utf-8";

(:: OracleAnnotationVersion "1.0" ::)

(:: pragma  type="ctx:route" ::)

declare namespace xf = "http://www.rubix.nl/test/routingexample/";

declare namespace ctx = "http://www.bea.com/wli/sb/context";

declare function xf:mapping ()

    as element(*) {

    <mappings>

        <mapping>

            <Customer>A</Customer>

            <Service>CustomerService/business/CustomerServiceA</Service>

        </mapping>

        <mapping>

            <Customer>B</Customer>

            <Service>CustomerService/business/CustomerServiceB</Service>

        </mapping>

    </mappings>

};

declare function xf:checkDefault($value as xs:string*)

    as xs:string {

    if (exists($value))

    then $value

    else xf:mapping()/mapping[Customer="A"]/Service/text()

};

declare function xf:selectBusinessService($customer as xs:string)

    as xs:string {

    xf:checkDefault(xf:mapping()/mapping[Customer=$customer]/Service/text())

};

declare function xf:DetermineCustomerEndpoint($customer as xs:string)

    as element(*) {

    <ctx:route>

        <ctx:service isProxy="false">{ xf:selectBusinessService($customer) }</ctx:service>

        <ctx:operation>Order</ctx:operation>

    </ctx:route>

};

declare variable $customer as xs:string external;

xf:DetermineCustomerEndpoint($customer)

With this custom XQUERY file, A Xquery function "DetermineCustomerEndpoint" will be called where it will do following tasks:

1. Dynamic Routing will call "DetermineCustomerEndpoint".
2. "DetermineCustomerEndpoint" will check whether proxy services will be called or business service be called, This condition with be decided based on "True"/"False" of isProxy.
3. "DetermineCustomerEndpoint" will call function "selectBusinessService" where it will send CustomerType as in variable "$customer".
4. "selectBusinessService" will execute and call another xquery function "checkDefault".
5. "checkDefault" function will validate value of "$customer", whether it is "A" or "B".
6. In "checkDefault" function, Based on input values Mapping XML will execute and business service absolute path will be return.
7. Same business service path will be executed.

You can deploy and test it over OSB console.