The REST Adapter can be used to implement the following categories of use cases.
When you provision a new instance of Oracle Integration, several sample integrations are automatically included. Many of these samples are configured with the REST Adapter. These fully designed samples help you get up and running quickly and show you how easy it is to activate, invoke, and monitor an integration between endpoints. See Running the Sample Integrations of Using Integrations in Oracle Integration.
Modernize the Existing Capability
There are scenarios in which partners or in-house client applications can consume only REST APIs. The capability is exposed through non-HTTP interfaces such as JDBC. Or the capability is exposed as a SOAP API. For example, status of the orders may reside in an on-premises database that must be retrieved using a SQL query. You can build an integration that retrieves order status and exposes it as a REST API by configuring the REST Adapter connection as a trigger.
Shape the API Based on a Client Application's Needs
There are scenarios in which partners or in-house or channel-specific client applications warrant only a very small subset of information compared to what is exposed by back end data sources. For example, the Get Order SOAP operation exposed by the back end Oracle ERP Cloud application can return several hundred attributes, while the client applications may need less than one-tenth of that. You can build an integration that consumes the SOAP service to retrieve the order details and exposes them as a REST API by configuring the REST Adapter connection as a trigger. The response message for this new REST API can reflect only the needed set of attributes by the client applications. The mapping of data from the back end SOAP service to the REST API-specific response message is performed only for the subset of attributes.
Provide a Coarse-Grained API Based on a Client Domain's Needs
There are scenarios in which the partners or in-house or channel-specific client applications warrant an API that may not be exposed at the same level of granularity by back end systems. For example, you want to expose an API to your partners for creating a sales order in your application. However, the sales order application may need multiple service invocations for creating one order. Exposing a single API for creating an order to partners abstracts the internal implementation details. You can accomplish this by developing an integration that can send multiple service invocations to the back end systems and expose them as a single REST API by configuring the REST Adapter connection as a trigger.
No Application Adapter for an External REST API
Even though Oracle Integration delivers many adapters for facilitating integration with specific applications, there are still several applications/capabilities for which specific adapters are missing. In other situations, an integration can be built to invoke these external REST APIs by configuring the REST Adapter connection as an invoke.
Convert an Unmanaged API into an OAuth2–Protected API
Applications with unprotected APIs or APIs protected using user credentials generally are difficult to expose publicly. While an unprotected API can be misused, an API protected using user credentials requires a higher level of trust with the client. Also, a change in user credentials implies that the client applications also need to update the credentials. You can create an integration that invokes such APIs and exposes them through a REST Adapter connection configured as a trigger, which is protected using OAuth 2.