1 Getting Started with OracleAS Integration InterConnect

OracleAS Integration InterConnect Components

OracleAS Integration InterConnect has the following core components:

• OracleAS Integration InterConnect Hub

• OracleAS Integration InterConnect Adapters

• OracleAS Integration InterConnect Development Kit

Supported Messaging Paradigms

OracleAS Integration InterConnect supports the following messaging paradigms. These paradigms are defined in iStudio at design time. The definitions are used at run time to route the messages suitably:

• Publish/Subscribe Messaging: An application publishes a message if it sends data to the OracleAS Integration InterConnect hub without knowing the destination applications. In addition, data is not expected in return. An application subscribes to a message if it receives the data from the OracleAS Integration InterConnect hub regardless of the application that sent the data. Also, it does not send any data in return. Events in iStudio are used to model this paradigm.

• Request/Reply Messaging: An application publishes a message and expects a message in return as a reply. The application subscribing to the request sends a reply to the sender after processing the request. Procedures in iStudio are used to model this paradigm. Request/Reply has two types of messaging:

  • Synchronous: The application making the request is blocked until it receives a reply.

  • Asynchronous: The application makes the request and proceeds with processing. It does not wait for a response. A reply is delivered asynchronously and is consumed by the application.

• Point-to-Point Messaging: Both Publish/Subscribe and Request/Reply can acquire a point-to-point characteristic if the sending application explicitly specifies which application should receive the message. This can be modeled using content-based routing in iStudio.

Design Time

During design time, a business analyst uses iStudio to define the integration objects, the applications that participate in the integration, and the specifications of the data exchanged between applications. All the specifications are stored as metadata in the OracleAS Integration InterConnect Repository. In addition, one or more OracleAS Integration InterConnect adapters are configured to service each application participating in the integration.

Run Time

At run time, when an application sends messages, the adapters attached to it retrieve the metadata from the repository, determine message format, perform transformations, and route the message to corresponding queues in the OracleAS Integration InterConnect hub.

For applications receiving messages, the adapters retrieve the metadata from the repository to receive messages from the OracleAS Integration InterConnect hub queues, determine message formats, perform transformations, and then deliver the messages to the application.

Separation of Integration Logic and Platform Functionality

Integration using OracleAS Integration InterConnect is a two-step process. During design time, integration logic is modeled in iStudio and captured in the repository as metadata. Metadata is created in the repository using iStudio during design time and is represented by application views, common views, and transformations. At run time, the underlying services treat this metadata as run-time instructions to enable the conversation among participating applications. Integration has two components:

• Integration logic: Consists of the business rules and transformation logic necessary to integrate heterogeneous systems. Using iStudio, this integration logic can be modeled and the results stored in the repository as metadata.

• Platform functionality: Consists of the integration infrastructure provided with OracleAS Integration InterConnect and the Oracle Database. In addition, OracleAS Integration InterConnect provides application and protocol adapters. The platform services provide the infrastructure necessary for integration.

Unique Integration Methodology

iStudio exposes an integration methodology that eliminates the complexities of point-to-point custom integration solutions. The integration methodology is based on a hub-and-spoke model.

How the Hub-and-Spoke Model Works

An integration point is the context, which ties in a particular message exchange, between two or more participating applications in the integration scenario. OracleAS Integration InterConnect supports two types of integration points:

• Events: This type of integration point is used to model the publish/subscribe messaging paradigm.

  For example, an integration scenario may require that customer information across two applications be synchronized in real time. Whenever a new customer is created in the application, App1, the customer should also be created in the application, App2. Create_Customer is an event that triggers communication between the two applications. App1 produces the information, and App2 consumes it. In this scenario, create_customer is an integration point.

• Procedures: This type of integration point is used to model the request/reply messaging paradigm.

  For example, a user of an application App1 may request information about an item stored in application App1. The information about the requested item might be segmented across the two applications App1 and App2. To give a meaningful response to the user of App1, it is necessary to query App2 for information about the item. Get_Item_Info is an integration point between the two applications because it triggers communication between the two applications. App1 produces a query, and App2 consumes it. App2 produces the response, and App1 consumes it.

The common view consists of a list of such integration points, each with its own associated data. Applications participate in the integration by binding to one or more of these common view integration points.

For each binding, applications have their own application view of data that needs to be exchanged. Each binding involves a mapping, or transformation, between the application view and the common view in the context of the integration point. In this model, the application views are the spokes and the common view is the hub.

illustrates an example of the hub-and-spoke model, where the common view is the hub and the application views are the spokes.

Figure 1-2 OracleAS Integration InterConnect Hub-and-Spoke Model

Description of "Figure 1-2 OracleAS Integration InterConnect Hub-and-Spoke Model"

The application view for App1 contains: First Name, Last Name, Middle Initial, and Prefix. Similarly, the application view for App2 contains: Name (one field that describes Last Name and First Name).

In this example, Create_Customer is an integration point. If the information to exchange is only the new customer's name, the common view has all the information potentially captured in a name defined in an application-independent method. This information must be a superset of all the information that needs to be exchanged between App1 and App2, for example, Prefix, First Name, Last Name, Middle Initial, Maiden Name, and Suffix.

When App1 sends this information out or publishes an event, transformations are defined from its application view to the common view. When App2 receives this information or subscribes to an event, transformations are defined from the common view to its application view.

The hub-and-spoke model has the following advantages:

• Loosely Coupled Integration: If applications are integrated directly with each other, then any change in one application will result in changes required for the other applications. In OracleAS Integration InterConnect, applications integrate to the common view and not directly with each other. This reduces the number of integration interfaces.

• Easy Customization: If an application is upgraded or changed, then only the corresponding application view needs to be remapped to the hub. The other spokes and their relationships with the hub remain unchanged. This localizes the change impact to the affected application.

• Easy Extensibility: If an application is added or removed from the integration scenario, then other integrated applications are not affected. For example, if a new application is added to the integration scenario, then it must define its spoke component (the application view) and map that component to the hub (common view) for each integration point. This does not affect other applications in the integration.

• Enhanced Reusability: If the common view of an application is already built, then this common view can be reused to integrate the application with any other application. For example, to integrate the Marketing CRM module to SAP, the integration would be from iMarketing to common view to SAP. If there is a requirement to integrate iMarketing to Peoplesoft, then the iMarketing to common view integration can be reused. Only the common view to the Peoplesoft integration needs to be built.

Integration Lifecycle Management

Managing, customizing, and evolving an integration over time is as important as creating the integration in the first place. The hub-and-spoke integration model has advantages to help achieve this goal. In addition, the OracleAS Integration InterConnect repository, which contains all the integration logic, provides extensive services for managing changes over time. The repository provides fine-grained versioning of all OracleAS Integration InterConnect first class objects such as events, messages, and data types. Some important aspects of versioning to aid the lifecycle support include:

• Basic Versioning: New versions of first class objects, such as messages, can be created to address changing integration needs. Different versions of the same object can coexist in the repository. This approach has two advantages:

  • Eliminates the need for an expanded namespace to address modifications

  • Allows related entities to be grouped together for easy management

• Multiple Active Versions: Multiple versions of the same message can be active in the same integration scenario simultaneously. This helps transition and integration incrementally without requiring changes to existing messages. For example, if a purchase order definition for an application or the application view of the purchase order needs to change, then a new version of the message can be created and activated for that application. Once this metadata is created, the application can smoothly transition from sending and receiving messages based on the old definitions to the new one.

• Migration Support: Different versions of metadata can be migrated across repositories on a first class object basis. This feature enables fine-grained control of content in different repositories, such as a development repository and a production repository.

• Consistency Control: OracleAS Integration InterConnect detects and flags metadata conflicts. This helps prevent accidental overwriting of metadata and maintains consistency of metadata in the repository.

Using Adapters for Integration

Adapters are run-time components, which process integration logic captured in the repository as run-time instructions, to enable the integration. Prepackaged adapters help applications at run time to participate in the integration without any programming effort.

Adapters perform the following tasks:

• Application Connectivity: Adapters connect applications with OracleAS Integration InterConnect hub to transfer data between them. The logical subcomponent within an adapter that handles this responsibility is called a bridge. This is the protocol/application-specific piece of the adapter that communicates with the application.

  For example, the database adapter can connect to an Oracle database using JDBC and run-time SQL APIs. The bridge subcomponent only knows how to call the correct APIs.

• Transformations: Transform data from the application view to common view and conversely as dictated by the repository metadata. In general, adapters are responsible for carrying out all the run-time instructions captured through iStudio as metadata in the repository. Transformations are an important subset of these instructions. The logical subcomponent within an adapter that handles the run-time instructions is called an agent. This is the generic run-time engine in the adapter that is independent of the application to which the adapter connects. It focuses on the integration scenario based on the integration metadata in the repository. There is no integration logic coded into the adapter itself. All integration logic is stored in the repository. The repository contains the metadata that drives this subcomponent.

  In the preceding database adapter example, the bridge subcomponent knows which SQL APIs to call but not how to call them. All adapters have the same agent code but the metadata is different. This difference in metadata controls and differentiates the behavior of each adapter.

The OracleAS Integration InterConnect Adapter Architecture is displayed in .

Figure 1-3 OracleAS Integration InterConnect Adapter Architecture

Description of "Figure 1-3 OracleAS Integration InterConnect Adapter Architecture"