Design objects are always assigned to one software component version. The uniqueness of an object is determined by the name and namespace, not by the software component version.
The table shows the most important design objects in the form of a hierarchy. The root nodes are service interfaces.
Most Important Design Objects
| Design Object | Function | Mandatory |
|---|---|---|
| Service Interface | Encapsulates message types and defines parameters for running | Yes |
| Message Types | Encapsulates data types | Yes |
| Data Types | Describe the structure of the data that can be exchanged | Yes |
| Mappings | Structure and data mapping on XML basis | No |
| Imported Objects | IDoc and method signatures of BAPIs can be imported | No |
| External Definitions | Externally-defined data structure that is imported into the ES Repository | No |
| Context objects | An abstracted alias of a specific part of a data type | No |
Data Types
Data types are the basic components of interfaces and define simple or complex XML data structures that you create or import in a data type editor.
With SAP Process Integration (PI), you determine the structure of data types based on their classification.
The various data types are as follows:
- Freely modeled data types
- Core Data Types (CDT's)
- Aggregated Data Types
SAP uses CDTs and aggregated data types to create the signature of enterprise services.
Message Types
The message type describes the structure of a message that SAP Process Integration (PI) sends or receives and determines the root element of the message. The message type references a single and complex data type and can be used for both outbound and inbound service interfaces.
An eXtensible Markup Language Schema Definition (XSD) version of the message type is provided in the Enterprise Services Repository (ESR) for the export of the interface.
Service Interfaces
All interfaces involved in the message flow of the scenarios should be stored in the ESR. In this way, you can choose the interface objects using input help during configuration.
Service Interfaces belong to one of these categories:
- Inbound (provides a function by an application - Receiver system)
- Outbound (calls a function of an application - Sender system)
A service interface represents a set of functions that is either provided by an application (inbound service interface) or used by an application (outbound service interface). You can consider the set of functions a service interface represents as a subset of the functions implemented by a process component. However, a service interface in the Enterprise Services Repository contains merely the metadata of a service, abstracted from any implementation details.
Service interfaces are based on the Web Services Description Language (WSDL), an XML-based language for describing Web Services and how to access them. However, when you create interface objects in the Enterprise Services Repository, you do not need to be familiar with the syntax of WSDL because you can use the relevant editor to specify the interface attributes.
External Definition of Interfaces
You can import interfaces into the Enterprise Services Repository (ESR) with structures that have been defined using the following:
- Web Service Description Language (WSDL)
- XML Schema Definition (XSD)
- Data Type Definition
Imported Objects
You can import Remote Function Call (RFC) signatures and Intermediate Document (IDoc) types from the SAP system by using an RFC. This enables you to generate an XML schema.
In this case, connection data to the SAP system containing the current RFC signatures or IDoc types is defined for the software component.
SAP only delivers some RFC signatures and IDoc types of the software components in the ESR.