{preceding_version_uid} as path or header parameter?

[jakesmolka]

Updating resources COMPOSITION and DIRECTORY are somewhat similar methods (in scope of this question), but providing {preceding_version_uid} is handled differently in each case.

• PUT /ehr/{ehr_id}/composition/{preceding_version_uid} contains the uid as path parameter
• PUT /ehr/{ehr_id}/directory contains the uid as If-Match header parameter, which is said to be mandatory

Same is true for deletion too.

Why do these cases need different implementations of providing {preceding_version_uid}?

[jakesmolka]

Sorry, just found the reason: https://openehr.github.io/specifications-ITS/ehr.html#design-considerations-http-headers

But to understand it completely, I really would like to know why "This is only required by a small set of resources"? I could image that directory objects are way more likely to be target of multiple requests at the same time than a specific composition. That's not really a technical explanation though.

[bostjanl]

We will change the composition PUT to use versioned_object_uid as path parameter and If-Match header for preceding version_uid.