|Oracle E-Business Suite Integrated SOA Gateway User's Guide|
Part Number E12064-06
Service enablement is a key requirement for developing manageable, profit-generating Web services. For example, if you are a service provider, service enablement enables you to dynamically provision new Web services and meter the use of those services. If you are a Web site hoster, service enablement helps you to host multiple customers across a shared infrastructure, and also helps you to set and monitor service level agreements with those customers.
Note: Web services are Web-based applications that provide a standard means of interoperating between different software applications, running on a variety of platforms or frameworks. Web services have an interface described in a machine-processable format called WSDL (Web Services Description Language). Other systems interact with the Web service in a manner prescribed by its description using SOAP (Simple Object Access Protocol) messages, typically conveyed using HTTP with an XML serialization in conjunction with other Web-related standards.
The common service-oriented architecture used in enabling Web services is illustrated in the following diagram:
A service provider is the primary engine underlying the Web services. It describes its Web services using WSDL and actually provides or implements the business functionality of various types. The WSDL definition is published to a service broker.
A service broker describes the service's location and contract. It is responsible for ensuring the service information is available to any potential service requestor, consumer, or called Web service client.
A service consumer or Web service client issues one or more queries to the service broker to locate a service and determine how to communicate with that service.
WSDL and SOAP are the communication vehicles facilitating the services. Part of the WSDL provided by a service provider is passed to the service consumer in specifying what the requests and responses are for the service provider. The service consumer sends SOAP messages as service requests to the service provider. The service provider then provides the expected SOAP responses back to the service consumer to complete the requests.
Service Enablement and Oracle E-Business Suite Integrated SOA Gateway
Service enablement is the essential feature within Oracle E-Business Suite Integrated SOA Gateway. It provides a mechanism that allows native packaged integration interface definitions residing in Oracle Integration Repository (the service broker) to be transformed into Web services described in WSDL code. Additionally these services can be further deployed to Oracle Application Server allowing more consumptions over the Web.
For example, PL/SQL integration interface definitions can be service enabled within Oracle E-Business Suite, and then deployed as Web services. Third party clients can discover them and initiate transactions with Oracle E-Business Suite.
For more information about services, refer to the Oracle Application Framework Developer's Guide, available from My Oracle Support Knowledge Document 1087332.1, Oracle Application Framework Release Notes for Release 12.1.3.
The following concepts or terminologies are commonly used in service-oriented architecture.
The primary engine underlying the Web services capability is Service Provider. To support all published integration interface types and services in Oracle E-Business Suite Integrated SOA Gateway, an enhanced Web Service Provider called SOA Provider is particularly used here to achieve the necessary functionality of a service provider plus additional features in supporting various interface types.
The service consumers or Web service clients are the parties that use or consume the services provided by a service provider.
The consumer locates entries in the service broker using various find operations and then binds to the service provider in order to invoke one of its Web services.
Service broker plays an important role in the service-oriented architecture. The service broker is responsible for making the service interface and implementation access information available to any potential service requestor. The scope of a service broker can be decided based on the business needs. For example, a public registry or broker is available through the Internet, while a private broker is only accessible to a limited audience such as users of a company intranet.
A service broker is the key component of any SOA-based infrastructure which enables service providers to advertise their service offerings, allows service consumers to find, access, and invoke services that meet defined criteria, as well as provides critical features for SOA governance.
Web services provide access to software systems over the Internet using standard protocols. Therefore, there exists at least a Web service provider that publishes certain services such as computer repair services, and a Web service consumer that uses the services. Web service discovery is the process of finding a suitable Web service for a given task.
Simple Object Access Protocol (SOAP) is a protocol for exchanging XML-based messages over networks, normally using HTTP/HTTPS.
SOAP forms the foundation layer of the Web services stack, providing a basic messaging framework upon which abstract layers can be built.
In Web service environment, SOAP provides a standard way of structuring these XML documents and acts as a building block for Web service communication. For example, Web service provider receives SOAP requests from Web service clients to invoke Web services and also sends the corresponding SOAP responses out to the clients.
WSDL is a format for describing a Web Services interface. It is a way to describe services and how they should be bound to specific network addresses.
WSDL has three parts:
Definitions are generally expressed in XML and include both data type definitions and message definitions that use the data type definitions. These definitions are usually based upon some agreed upon XML vocabulary which could be within an organization or between organizations.
Operations describe actions for the messages supported by a Web service. Operations are grouped into port types. Port types define a set of operations supported by the Web service.
Service bindings connect port types to a port. A port is defined by associating a network address with a port type. A collection of ports defines a service. This binding is commonly created using SOAP.
The following figure shows the relationship of the basic parts of WSDL:
Web service security (WS-Security) is a communication protocol providing a means for applying security to Web Services. It describes enhancements to SOAP messaging to provide quality of protection through message integrity, message confidentiality, and single message authentication.
In addition, WS-Security describes how to attach signature and encryption headers to SOAP messages. It also describes how to attach security tokens to the messages to reinforce security rules and guard Web service content from unauthorized access.
To allow pre-built and reusable business services available to customers and let customers dynamically interact between applications, Oracle E-Business Suite Integrated SOA Gateway, building on the principle of service-oriented architecture, allows service enablement within the Oracle E-Business Suite. As a result, integration interface definitions that have been used internally within an organization are now Web available.
The following diagram illustrates the essential SOA components in enabling services within Oracle E-Business Suite:
Service-Oriented Architecture in Oracle E-Business Suite
In this diagram, SOA Provider is the service provider used in enabling services. Oracle Integration Repository plays a role as a service broker. The Web service invocation framework (WSIF) serves as a service consumer to issue a request through the invocation of a Web services from Oracle E-Business Suite.
SOA Provider is an enhanced service provider particularly in supporting additional interface types for service enablement.
Note: In Release 12.0, Oracle E-Business Suite is service partially enabled using Web Service Provider to enable XML Gateway Map and Business Service Object (formerly known as Service Bean) interface types. For backward compatibility, Oracle E-Business Suite Integrated SOA Gateway continues to support the Release 12.0 based Web Service Provider service enablement, plus additional interface types using SOA Provider to enable services.
At run time, SOA Provider references integration services and data from Oracle Integration Repository in processing inbound SOAP request messages that invoke Web services and sends the SOAP response out.
Web Service Invocation Framework
To invoke integration services from Oracle E-Business Suite, Oracle E-Business Suite Integrated SOA Gateway uses service invocation framework, leveraging Oracle Workflow Java Business Event System (JBES) and a seeded Java rule function, to allow any WSDL-described service to be invoked.
For more information about how to set up and invoke a Web service through the invocation framework, see Implementing Service Invocation Framework, Oracle E-Business Suite Integrated SOA Gateway Implementation Guide and Oracle Workflow and Service Invocation Framework Overview, Oracle E-Business Suite Integrated SOA Gateway Developer's Guide.
Oracle Integration Repository
Oracle Integration Repository, an integral part of Oracle E-Business Suite, is the centralized repository that contains numerous interface endpoints exposed by applications within the Oracle E-Business Suite. It provides a comprehensive, consistent browsing view of the interface mechanism which lets you easily discover and search on the business interface from the catalog. Additionally, users with administrator role can generate Web services by transforming interface definitions to a machine-processable format that complies with Web standards using WSDL. Once a Web service is successfully generated, the service can be deployed to the Oracle Application Server.
The Web service generation and deployment process flow can be illustrated in the following diagram:
Service Generation and Deployment Process Flow
The following diagram illustrates the service enablement process flow within Oracle E-Business Suite:
Service Enablement Functional Process Flow
An integration repository administrator transforms the integration interface definitions resided in Oracle Integration Repository into Web services in WSDL URLs.
You can view the WSDL sources in the Web Service region. See: Reviewing Web Service WSDL Source.
An integration repository administrator then deploys Web services.
How to generate and deploy Web services, see: Performing Additional Web Service Activities.
Web services representing in WSDL URLs can be invoked from any Web service clients.
In addition to transforming interface definitions into Web services and deploying them, integration repository administrators can access the SOA Monitor user interface to monitor and manage all SOAP messages in and out from the SOA Provider (if the SOA monitoring feature is enabled). This allows any operation error if occurred during the message exchanges to be identified and audited. The administrators can search and view SOAP request and response message details, and take necessary actions if needed to expedite the interaction between services and consumers. For more information on how to use SOA Monitor, see Monitoring and Managing SOAP Messages Using SOA Monitor, Oracle E-Business Suite Integrated SOA Gateway Implementation Guide.
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