You can fetch link interface properties for an object using the OData function GetLinkInterfacePropertiesForObject.
The following example GET looks for the SPFColumnSize and SPFColumnDisplayAs link properties to the SPFColumnSetColumnItem_12 relationship.
<ACCESS_URL>/api/v2/SDXDEV/GetLinkInterfacePropertiesForObject(ObjectID='000AN0A', RelDefUIDWithDirection='SPFColumnSetColumnItem_12', LinkProperties='SPFColumnSize,SPFColumnDisplayAs')
This GET returns the following output:
{
"@odata.context":
"<ACCESS_URL>/api/v2/SDXDEV/$metadata#Collection(Intergraph.SPF.Server.API.ClientSupport.Types.LinkPropertyValue)",
"value":
[
{
"propertyDefUID": "SPFColumnSize",
"propertyValue": "14",
"otherEndOBID": "0004FPA",
"otherEndUID": "CI_LastUpdateDate"
},
{
"propertyDefUID": "SPFColumnDisplayAs",
"propertyValue": "Last Updated",
"otherEndOBID": "0004FPA",
"otherEndUID": "CI_LastUpdateDate"
},
The results returned depend on the relationship direction being set.