[#54,backend/es][m]: ElasticSearch backend (readonly atm) - fixes #54.

src/backend/elasticsearch.js

@@ -0,0 +1,75 @@
+this.recline = this.recline || {};
+this.recline.Backend = this.recline.Backend || {};
+
+(function($, my) {
+  // ## ElasticSearch Backend
+  //
+  // Connecting to [ElasticSearch](http://www.elasticsearch.org/)
+  //
+  // To use this backend ensure your Dataset has a elasticsearch_url,
+  // webstore_url or url attribute (used in that order)
+  my.ElasticSearch = Backbone.Model.extend({
+    _getESUrl: function(dataset) {
+      var out = dataset.get('elasticsearch_url');
+      if (out) return out;
+      out = dataset.get('webstore_url');
+      if (out) return out;
+      out = dataset.get('url');
+      return out;
+    },
+    sync: function(method, model, options) {
+      var self = this;
+      if (method === "read") {
+        if (model.__type__ == 'Dataset') {
+          var base = self._getESUrl(model);
+          var schemaUrl = base + '/_mapping';
+          var jqxhr = $.ajax({
+            url: schemaUrl,
+            dataType: 'jsonp'
+          });
+          var dfd = $.Deferred();
+          my.wrapInTimeout(jqxhr).done(function(schema) {
+            // only one top level key in ES = the type so we can ignore it
+            var key = _.keys(schema)[0];
+            var fieldData = _.map(schema[key].properties, function(dict, fieldName) {
+              dict.id = fieldName;
+              return dict;
+            });
+            model.fields.reset(fieldData);
+            dfd.resolve(model, jqxhr);
+          })
+          .fail(function(arguments) {
+            dfd.reject(arguments);
+          });
+          return dfd.promise();
+        }
+      } else {
+        alert('This backend currently only supports read operations');
+      }
+    },
+    query: function(model, queryObj) {
+      var base = this._getESUrl(model);
+      var data = _.extend({}, queryObj);
+      var jqxhr = $.ajax({
+        url: base + '/_search',
+        data: data,
+        dataType: 'jsonp'
+      });
+      var dfd = $.Deferred();
+      // TODO: fail case
+      jqxhr.done(function(results) {
+        model.docCount = results.hits.total;
+        var docs = _.map(results.hits.hits, function(result) {
+          var _out = result._source;
+          _out.id = result._id;
+          return _out;
+        });
+        dfd.resolve(docs);
+      });
+      return dfd.promise();
+    }
+  });
+  recline.Model.backends['elasticsearch'] = new my.ElasticSearch();
+
+}(jQuery, this.recline.Backend));
+