[#62,faceting][s]: introduce Facet and FacetList models and use them.

* Conceptual breakthrough on how Faceting and Filtering interact (have updated issue #62 as a result).

demo/js/app.js

@@ -95,9 +95,10 @@ function localDataset() {
   backend.addDataset(inData);
   var dataset = new recline.Model.Dataset({id: datasetId}, backend);
   // TODO: auto-compute in Memory backend ??
-  dataset.facets = {
-    'country': {
-      terms: [
+  dataset.facets = new recline.Model.FacetList([
+    {
+      id: 'country',
+      result: [
         {
           term: 'UK',
           count: 3
@@ -112,7 +113,7 @@ function localDataset() {
         }
       ]
     }
-  };
+  ]);
   return dataset;
 }
 

src/model.js

@@ -23,7 +23,7 @@ my.Dataset = Backbone.Model.extend({
     }
     this.fields = new my.FieldList();
     this.currentDocuments = new my.DocumentList();
-    this.facets = {};
+    this.facets = new my.FacetList();
     this.docCount = null;
     this.queryState = new my.Query();
     this.queryState.bind('change', this.query);
@@ -119,24 +119,36 @@ my.Query = Backbone.Model.extend({
     , from: 0
     , facets: {}
   },
-  initialize: function() {
-    _.bindAll(this, 'addFacet');
-  },
+  // Set (update or add) a terms filter
+  // http://www.elasticsearch.org/guide/reference/query-dsl/terms-filter.html
+  setFilter: function(fieldId, values) {
+  }
+});
 
+my.Facet = Backbone.Model.extend({
+  defaults: {
+    query: null,
+    result: null
+  }
+});
+
+my.FacetList = Backbone.Collection.extend({
+  model: my.Facet,
   addFacet: function(fieldId) {
-    // TODO: utilize field info to determine facet type ??
-    var facets = this.get('facets');
-    if (fieldId in facets) {
+    // Assume id and fieldId should be the same (TODO: this need not be true if we want to add two different type of facets on same field)
+    if (fieldId in this) {
       return;
     }
-    facets[fieldId] = {
-      terms: {
-        field: fieldId
+    // TODO: utilize field info to determine facet type ??
+    var facet = new my.Facet({
+      id: fieldId,
+      query: {
+        terms: {
+          field: fieldId
+        }
       }
-    } 
-    this.set({facets: facets});
-    // trigger change event (does not seem to be triggered o/w)
-    // this.change();
+    });
+    this.add(facet);
   }
 });
 

src/view.js

@@ -168,11 +168,9 @@ my.DataExplorer = Backbone.View.extend({
       model: this.model.queryState
     });
     this.el.find('.header').append(queryEditor.el);
-    var queryFacetEditor = new my.QueryFacetEditor({
-        model: this.model.queryState
-      },
-      this.model
-      );
+    var queryFacetEditor = new my.FacetQueryEditor({
+      model: this.model
+    });
     this.el.find('.header').append(queryFacetEditor.el);
   },
 
@@ -281,58 +279,52 @@ my.QueryEditor = Backbone.View.extend({
   }
 });
 
-my.QueryFacetEditor = Backbone.View.extend({
+my.FacetQueryEditor = Backbone.View.extend({
   className: 'recline-query-facet-editor', 
   template: ' \
-      <a class="btn dropdown-toggle" data-toggle="drop-down">Add filter on</a> \
-      <ul class="dropdown-menu js-faceton"> \
-      {{#fields}} \
-      <li name="{{id}}">{{label}}</li> \
-      {{/fields}} \
+    <div class="dropdown js-add-facet"> \
+      <a class="btn dropdown-toggle" data-toggle="dropdown" href=".js-add-facet">Add Facet On <i class="caret"></i></a> \
+      <ul class="dropdown-menu"> \
+        {{#fields}} \
+        <li><a href="#{{id}}">{{label}}</a></li> \
+        {{/fields}} \
       </ul> \
+    </div> \
     <div class="facets"> \
       {{#facets}} \
-        <a class="btn js-facet-show-toggle" data-facet="{{label}}"><i class="icon-plus"></i> {{label}}</a> \
-        <ul class="facet-items" data-facet="{{label}}" style="display: none;"> \
-        {{#terms}} \
+        <a class="btn js-facet-show-toggle" data-facet="{{id}}"><i class="icon-plus"></i> {{id}} {{label}}</a> \
+        <ul class="facet-items" data-facet="{{id}}" style="display: none;"> \
+        {{#result}} \
           <li>{{term}} ({{count}}) <input type="checkbox" class="facet-choice" data-facet="{{label}}" value="{{term}}" /></li> \
-        {{/terms}} \
+        {{/result}} \
         </ul> \
       {{/facets}} \
     </div> \
   ',
 
   events: {
-    'change .js-faceton': 'onAddFilter',
+    'click .js-add-facet .dropdown-menu a': 'onAddFacet',
     'click .js-facet-show-toggle': 'onFacetShowToggle'
   },
-  initialize: function(model, dataset) {
+  initialize: function(model) {
     _.bindAll(this, 'render');
     this.el = $(this.el);
-    this.model.bind('change', this.render);
-    this.dataset = dataset;
-    this.dataset.fields.bind('add', this.render);
-    this.dataset.fields.bind('reset', this.render);
-    this.dataset.fields.bind('remove', this.render);
+    this.model.facets.bind('all', this.render);
+    this.model.fields.bind('all', this.render);
     this.render();
   },
   render: function() {
     var tmplData = {
-      query: this.model.toJSON(),
-      fields: this.dataset.fields.toJSON()
+      facets: this.model.facets.toJSON(),
+      fields: this.model.fields.toJSON()
     };
-    tmplData.facets = _.map(this.dataset.facets, function(data, key) {
-      var out = _.extend({label: key}, data);
-      return out;
-    })
     var templated = $.mustache(this.template, tmplData);
     this.el.html(templated);
   },
-  onAddFilter: function(e) {
-    var fieldId = $(e.target).find('option:selected').attr('name');
-    this.model.addFacet(fieldId);
-    // calculate facets for that field (if not already there??) 
-    // re-render will happen automatically as dataset will have updated
+  onAddFacet: function(e) {
+    e.preventDefault();
+    var fieldId = $(e.target).attr('href').slice(1);
+    this.model.facets.addFacet(fieldId);
   },
   onFacetShowToggle: function(e) {
     e.preventDefault();

test/model.test.js

@@ -43,4 +43,11 @@ test('Dataset', function () {
   equal(out.fields.length, 2);
 });
 
+test('Facet', function () {
+  var facets = new recline.Model.FacetList();
+  facets.addFacet('xyz');
+  equal(1, facets.length);
+  deepEqual({terms: {field: 'xyz'}}, facets.get('xyz').get('query'));
+});
+
 })(this.jQuery);