drobbins / doc.js

A tiny document store with indexed map-reduce views.

Doc.js

Document storage and processing via map-reduce.

Notes

• Documents here means JSON objects with a required id and revision field.

Usage

See the tests in test/spec/docSpec.js for more complete examples.

• Include this script
• Create a new store:

var store = new Doc.store();

• Put some documents in it:

store.save({id:123, name:"Aela"});
store.open(123);
store.remove(123);
store.unRemove(123);

• Create, run, and view results of map-reduce views on the data. A map function receives each doc, one at a time. A reduce function receives the concatenated results of it's corresponding map function accross all documents:

var map = function(doc){
        var words = doc.bio.split(" "),
            emits = [];
        words.forEach(function(word){
          emits.push({key:word.toLowerCase(), value:1});
        });
        return emits;
      },
      reduce = function(mapResults){
        var r = {}, count = 1;
        mapResults.forEach(function(kvPair){
          if (r.hasOwnProperty(kvPair.key)) { r[kvPair.key] += 1; }
          else {  r[kvPair.key] = 1; }
        });
        return r;
      };
store.saveView({id : "wordCount", map : map, reduce : reduce});

Persistence (WIP)

Doc offers a variety of persistence mechanisms, and can be readily extended to include your own. When a doc store is created, it can be passed a Doc.Backend object.

var store = new Doc.Store({backend = new Doc.RiakBackend()});

Included backends:

• Doc.DefaultBackend (not persisted)
• Doc.RiakBackend (TBI)
• Doc.CouchBackend (TBI)
• Doc.DynamoBackend (TBI)
• Doc.LocalStoreBackend (TBI)

You can also create your own:

var myBackend = new Doc.Backend({
  save : function(doc){...},
  open : function(id){...}
  ...
});
var store = new Doc.Store(myBackend);

Doc expects your backend to implement:

• save(doc)
• open(id)
• remove(id)
• WIP