TS 26.512 - Use of Read-only mandatory fields in PolicyTemplate resource

[davidjwbbc]

Description

The PolicyTemplate resource specified in TS 26.512 table 7.9.3-1 has several mandatory fields (Cardinality is 1..1) which are also read-only (all Usage operations are marked RO or -), meaning that they are only meaningful in API responses. The OpenAPI YAML specification in clause C.3.8 only marks these properties as being required meaning that the property is expected in both requests and responses. In fact, they should only be present in responses. In requests, these properties need to be ignored by the 5GMS AF.

There is therefore a discrepancy between table 7.9.3-1 and Annex C.3.8.

Suggested solution

Add the readOnly: true flag to the read-only mandatory fields in the OpenAPI YAML to signal that these fields are only required in an API response message, and will be ignored if present in an API request message.

Additional context

There are several other resources defined in TS 26.512 with mandatory fields that are also read-only and these should also be marked in the relevant OpenAPI YAML with the readOnly: true flag to improve the consistency between the Tables and the YAML.

[davidjwbbc]

This issue arose during implementing the feature while working on 5G-MAG/rt-5gms-application-function#70.

[rjb1000]

Change Request addressing this issue endorsed during yesterday's 3GPP SA4 ad hoc call:

• TS 26.512
  • Rel-17 CR0054 "[5GMS3, TEI17] Essential maintenance" in S4aI230145.
  • Rel-16: To be derived.

Revisions to be contributed to SA4#126 (Chicago).

[rjb1000]

Change Requests agreed at SA4#126 (Chicago):

• TS 26 512
  • Rel-17: CR0054r1 "Essential maintenance" in S4-231631.
  • Rel-16: CR0056 "Essential maintenance" in S4-231632.

[rjb1000]

CR Packs approved at SA#102 (Edinburgh):

• Rel-16: SP-231367.
• Rel-17: SP-231368.

[rjb1000]

• TS 26.512 V16.12.0 published.
• TS 26.512 V17.7.0 published.
• TS 26.512 V18.0.0 published.