Properties are for Guiding, not for Restricting
When you define a property-set with 'strongly-typed' property values, those values are used to provide an intuitive, guiding UI for tagging and locating items.
The actual value does not force a strong relationship to the original property-set's predefined values. This is by design, to not slow-down common repository operations and for keeping artifacts management simple by allowing properties to change and evolve freely over time, without worrying about breaking older property rules.
Properties are therefore a helpful and non-restrictive feature.
Creating a Property Set
To create a new property set, go to Admin | Artifactory | General | Property Sets and click New.
Add a Property Set Name, click New and add properties. The newly created property set will be available to use and add to a repository.
Adding Property Sets to Repositories
To add a property set, go to Application module | Artifacts and select a repository.
In the Properties tab, select the property sets you would like to add.
Attaching Properties via the UI
When selecting any item in the tree browser, you can view its Properties tab to view or edit the properties attached to the item.
You can edit the value of any property and click Save.
Attaching and Reading Properties via REST API
Properties are a special form of metadata and are stored on items just like any metadata - in XML form.
In fact, you can view properties not only from the Artifacts:Properties tab, but also from the Artifacts:Metadata tab, in which you can examine properties as they are stored in XML form. The properties XML is using the properties root tag and has a very simple format.
You can set, retrieve and remove properties from repository items via REST API, as you would do with any other XML-based metadata.