DataService API withHistory=true does not return history

[bulburDE]

Affected Version(s)
7.6.6.0

Describe the bug
I am trying to get the history of parts and characteristics using the Data Service API, but the history field is missing in the response.
In the planner I can see that the part has multiple versions. Also the "versioning active"(DE: Versionierung aktiv) checkbox in the top right corner of the planner is checked.

It seems like only the GET /parts endpoint is affected. I can successfully get the history of a characteristic using GET /characteristics

To Reproduce
Steps to reproduce the behavior:

1. Call the Data Service API at https://piweb-1.app.corpintra.net/MBC/dataServiceRest/parts?partPath=/TEST/PART/WITH/HISTORY&withHistory=true
2. Get the following response: {'attributes': {}, 'path': 'PPPP:/TEST/PART/WITH/HISTORY', 'charChangeDate': '2021-07-28T07:38:53.537Z', 'uuid': 'fd06b9f4-7a92-4c47-82ac-85584a7f4e40', 'comment': "test comment'.", 'version': 33607, 'timestamp': '2019-07-05T05:58:40.617Z'}

Expected behavior
The endpoint GET /parts should return the version history if withHistory=true is set.

[czthiele]

Hello @bulburDE,

it is important to distinguish between the API and the Planner at this point: when using the version overview in PiWeb Planner and clicking on a part, you will see all changes of this part and its characteristics. So it is possible that the multiple versions which you see are actually only changes of characteristics. The API however will return only part history on the parts endpoint and characteristic history on the characteristics endpoint, the Planner later combines it. You could try to actually edit the part atributes (e.g. rigth click on the part -> edit attributes) to create a new version of the part. Then the response of the parts endpoint should contain history, I tried it myself using PiWeb 7.6.6.

I hope this helps and clears things up a bit.