C0 Contract Rules for Providers of CDS Behavior Definitions

ABAP - Keyword Documentation → ABAP - Rules for Strict ABAP → Contract Rules for Released APIs → C0 Contract Rules → C0 Contract Rules for CDS Behavior Definitions →

Mail Feedback

Generally, a CDS behavior definition that is classified with the C0 contract must not be deleted after being released as an API but can become deprecated. BDEF extensions themselves must not be C0 released.

The following sections show the most important rules that a C0 contract imposes on CDS behavior definitions.

Prerequisites for C0 Release
Naming Rules
Stability Rules After Release
Example Topics

Prerequisites for C0 Release

General Rules

CDS behavior definitions can be released under the C0 stability contract for ABAP for Cloud Development. C0 release for ABAP for Key Users is not possible within ABAP Development Tools.
CDS behavior definitions of type managed, unmanaged, projection, and interface can be released under the C0 contract for extensibility. CDS abstract behavior definitions cannot be released for extensibility.
The behavior definition to be released must not have any syntax errors.
Strict mode version 2 must be used.
The respective BDEF must be enabled for extensibility using the keyword extensible in the CDS behavior definition header.

BDEF of Type managed or unmanaged

As a prerequisite for C0 release, each RAP BO must at least have one RAP BO interface that serves as interface for stable consumption. If this requirement is not met, release is still possible, but a warning message occurs.
If the RAP BO is draft-enabled, a draft query view is mandatory for each extensible RAP BO entity.
A draft query view must be C0 released if the RAP BO entity it belongs to is C0 released.
If the RAP BO has the implementation type unmanaged, the annotation @AbapCatalog.extensibility.allowNewCompositions: true is not allowed in the CDS view layer.
If the RAP BO has the implementation type managed, all RAP BO entities annotated with @AbapCatalog.extensibility.allowNewCompositions: true in the CDS view layer must be marked as extensible.

BDEF of Type projection

If a projection has already been released under the C1 contract, use system-internally, then C0 release is not possible.
Projections with use draft as dependent cannot be C0 released.

BDEF of Type interface

The base BO must released for C0 before the interface can be released.
The interface must first be released for C1.
If the base BO is draft-enabled, use draft is a prerequisite for C0 release.

Naming Rules

If the RAP BO has a namespace prefix, such as /PREFIX/, the names of its elements must not start with a different namespace prefix, nor with Z, nor with Y.
If the name of the RAP BO starts with Z or Y, there is no check.
In all other cases, the names of the elements must not start with Z, or Y, nor a namespace prefix.

The checks apply to the following elements:

Alias names of RAP BO entities.
External names of RAP BO entities.
Alias names of associations, specified using abbreviation.
Alias names of RAP foreign entities.
Names of RAP actions and RAP functions.
External names of RAP actions and RAP functions.
External names of action and function results.
Names of RAP determinations and RAP validations.
Names of RAP BO determine actions.
Names of RAP events.

Stability Rules After Release

General Rules

RAP draft handling must not be added or removed after release.
RAP BO entities and components that are explicitly marked as extensible must not be deleted or renamed and they must remain extensible.
RAP late numbering must not be added or deleted for extensible entities after release.

BDEF of Type managed or unmanaged

The BDEF implementation type (managed or unmanaged) must not change.
The RAP extensibility enablement settings must not be removed. This concerns the following properties:
A RAP own authorization context must not be removed (even if it is empty).
RAP BO entities declared as extensible must not be deleted and must remain extensible.
The name of the RAP persistent table of an extensible RAP BO entity must not changed nor be replaced by an unmanaged save (which would mean that no persistent table is specified).
Note: The reverse case is possible though. An unmanaged save can be replaced by a persistent table.
A draft query view in an extensible entity must not be added, nor replaced, nor deleted.
Extensible determine actions must not be deleted and must remain extensible. The name of an extensible determine action must not change.
Extensible RAP type mappings must not be deleted and must remain extensible. If an extensible RAP type mapping uses corresponding, then this addition corresponding must not be removed.

BDEF of Type projection

The BDEF implementation type must remain stable and must not change, for example, from projection to interface.
use draft must not be added or removed.
The projection must remain extensible.
The name of the projected BO must not change.
A RAP own authorization context must not be removed (even if it is empty).
RAP BO entities declared as extensible must not be deleted and must remain extensible.
Alias names of extensible entities must not be changed or deleted. New alias names can be added.
Extensible RAP type mappings must not be deleted and must remain extensible.

BDEF of Type interface

The name of the projected BO must not change.
use draft must not be added or removed.
Alias names must not change.
All associations exposed in an interface, including cross-BO associations and ancestor associations, must remain stable. They must not be deleted or disabled.

Example Topics

Example for a C0 released RAP BO which is extended from ABAP for Cloud Development.

Example for a C0 released service projection view which is extended from ABAP for Cloud Development.