Add support for storing/retrieving field values

I’ve made a (successful!) first pass at adding support for storing/retrieving field values. I added a fieldStore property to lunr.Index and populate that when the stored property of the field is true, e.g.,

var index = lunr(function () {
  this.ref('id');
  this.field('title',{boost:20, store: true});
  this.field('subtitle',{boost:10, store: true});
  this.field('bio',{boost:5});
  this.field('toc',{boost:5});
  this.field('desc',{boost:4});
});

and the result from lunr.Index.search(…) is

[ { ref: '4371',
    score: 0.02380936053390949,
    fields: 
     { title: '...',
       subtitle: '...' } },
  { ref: '395',
    score: 0.002723523438116153,
    fields: { title: '...' } } ]

To keep the serialize/deserialize functionality, I had to tweak the lunr.Store.load method so it isn’t directly coupled to lunr.SortedSet, because the value of lunr.Store entries is now an object instead of a SortedSet. Maybe I shouldn’t have used lunr.Store for this new fieldStore property, though?

If this is a feature that you’d like to have added, I’ll clean up my work and make sure all tests are passing…

[hoogw]

In 2019 I have same need !!!

the return result only show ref id. I actually want the real full json item associate with that ref id!!!

Otherwise, how I am going to use the returned ref id to retrieve the real full json element?

[kevinastone]

👍 I have an offline index step, so storing document metadata in the index would be beneficial.