rally lookback is lowest portfolio Item an indexed field?

Question

The lookback api docs say PortfolioItem field is an index. Is the lowest portfolio item type also an index?

E.g: the Portfolio Item types in my workspace are Product, Milestone and Feature. will Feature be an index in Lookback API in addition to PortfolioItem?

The reason I ask is because only top-level UserStories have the PortfolioItem field, but both top-level and child UserStories have the Feature field. I want to query all User Stories under a particular Feature, which means I can't use PortfolioItem field, because it will not include child User Stories, only top-level User Stories.

Example of what i want to do if Feature is indexed:

    Ext.create('Rally.data.lookback.SnapshotStore', {
        listeners: {
            load: function(store, data, success) {
                //do stuff
            }
        },
        autoLoad:true,
        limit:Infinity,
        fetch: ['ScheduleState', 'PlanEstimate', 'Feature', 'ObjectID'],
        compress:true,
        find: { 
            _TypeHierarchy: 'HierarchicalRequirement', 
            Children: null,
            Release: //a release OID
        },
        hydrate: ['ScheduleState']
    });

Answer 1

There may be some confusion with the use of the word 'index'. Some fields are "indexed" for fast lookup..."Feature" isn't one of them, though it is a valid field and you can search for it. More correctly, the field that is the lowest-level Portfolio Item type is kept in the snapshots.* Given what you're asking for, adding "Feature": {oid} to the find should give you what you want.

* The distinction is due to the fact that the label "Feature" can be changed to something else, so what is "Feature" in one workspace might be "Thing" in another.