XSLT, OData V2: no direct create for non-addressable entity sets

[ralfhandl]

Fixes #311

• If entity set Foo is not addressable, no post operation for path /Foo will be generated
• If it is creatable, a post operation for path /Parent(...)/to_Foo will be generated
• If it is updatable or deletable, patch or delete will be generated as usual for path /Foo(...)

Plus

• Remove leftover from unsuccessful experiment

[ralfhandl]

@sterlp Can you please check if this is what you expect?

Note: I made the AddressSet creatable, updatable, and deletable to cover all cases.

odata-openapi/tools/tests/addressable-v2.xml

Lines 102 to 103 in c0f90b2

	<EntitySet Name="AddressSet" EntityType="ZE_API_DEMO_SRV.Address" sap:pageable="false"
	sap:addressable="false" sap:content-version="1" />

[HeikoTheissen]

Why does /HeadSet('{BusinessPartner}')/to_Address appear for both HeadSet and AddressSet in Swagger?

AddressSet appears for PATCH and DELETE, but not for GET and POST (although it is creatable). Is that really what sap:addressable="false" means?

[ralfhandl]

Why does /HeadSet('{BusinessPartner}')/to_Address appear for both HeadSet and AddressSet in Swagger?

Each operation is tagged with both the source and the target entity set, and in this case the two are different.

The same happens for example here:

• https://api.sap.com/api/CE_SALESORDER_0001/resource/Sales_Order_Header
• https://api.sap.com/api/CE_SALESORDER_0001/resource/Sales_Order_Item

[ralfhandl]

AddressSet appears for PATCH and DELETE, but not for GET and POST (although it is creatable). Is that really what sap:addressable="false" means?

Yes, that is the historically grown meaning.

Originally sap:addressable="false" was invented for read-only CDS views with parameters:

• The view parameters are specified as "keys" of the "parameter" entity set, the results are then retrieved by following the Set navigation property to the actual "data" entity set.
• OData V2 does not have containment, so a top-level entity set for the "data" is needed. It is marked as sap:addressable="false" because it only allows indirect read access.

This then was later extended to writeable views:

• Create is create-by-association only, and this was not correctly reflected by the XSLT and is fixed now.
• Update and delete cannot be done via association because OData V2 defines that a two-segment path with two key segments is equivalent to a one-segment path with key segment addressing the target entity set, and this restriction is hard-wired into SAP NetWeaver Gateway for OData V2.

In OData V4 we use containment for CDS views with parameters, and all operations go via the "parameter" entity set and the containment navigation property Set.

[HeikoTheissen]

AddressSet appears for PATCH and DELETE, but not for GET and POST (although it is creatable). Is that really what sap:addressable="false" means?

Is the following reasoning correct?

Non-addressability removes the GET /AddressSet and POST /AddressSet, because there are the alternatives GET /HeadSet(...)/to_Address and POST /GET HeadSet(...)/to_Address. But there are no alternatives for PATCH and DELETE, so these remain.

If should be different if to_Address was a containment navigation property.

[HeikoTheissen]

Wrong Swagger output for containment navigation properties

If I add

<NavigationProperty Name="to_Address" Relationship="ZE_API_DEMO_SRV.to_Address"
          FromRole="FromRole_to_Address" ToRole="ToRole_to_Address" sap:containstarget="true" />

then Swagger contains

HeadSet

• PATCH /HeadSet(...)/to_Address(...)
• DELETE /HeadSet(...)/to_Address(...)

AddressSet

• PATCH /AddressSet(...)
• DELETE /AddressSet(...)

The resource paths given for AddressSet are invalid, they must equal the resource paths given for HeadSet.

[ralfhandl]

If should be different if to_Address was a containment navigation property.

Correct, and in OData V4 we use containment. In OData V2 there is no such thing.

[ralfhandl]

Wrong Swagger output for containment navigation properties

Thanks for finding this, it seems this undocumented OData V2 Annotation was a left-over from an unsuccessful experiment.