[model][m]: working Webstore Backend (fixes #8).

src/model.js

@@ -20,6 +20,13 @@ recline.DocumentList = Backbone.Collection.extend({
   model: recline.Document
 })
 
+// Backends section
+// ================
+
+recline.setBackend = function(backend) {
+  Backbone.sync = backend.sync;
+};
+
 // Backend which just caches in memory
 // 
 // Does not need to be a backbone model but provides some conveience
@@ -73,7 +80,68 @@ recline.BackendMemory = Backbone.Model.extend({
  }
 });
 
-recline.setBackend = function(backend) {
-  Backbone.sync = backend.sync;
-};
-
+// Webstore Backend for connecting to the Webstore
+//
+// Designed to only attached to only dataset and one dataset only ...
+// Could generalize to support attaching to different datasets
+recline.BackendWebstore = Backbone.Model.extend({
+  // require url attribute in initialization data
+  initialize: function() {
+    this.webstoreTableUrl = this.get('url');
+  }, 
+  getDataset: function(id) {
+    var dataset = new recline.Dataset({
+      id: id
+    });
+    dataset.backend = this;
+    return dataset;
+  },
+  sync: function(method, model, options) {
+    if (method === "read") {
+      // this switching on object type is rather horrible
+      // think may make more sense to do work in individual objects rather than in central Backbone.sync
+      if (this.__type__ == 'Dataset') {
+        // get the schema and return
+        var base = this.backend.get('url');
+        var schemaUrl = base + '/schema.json';
+        var jqxhr = $.ajax({
+          url: schemaUrl,
+          dataType: 'jsonp',
+          jsonp: '_callback'
+          });
+        var dfd = $.Deferred();
+        jqxhr.then(function(schema) {
+          headers = _.map(schema.data, function(item) {
+            return item.name;
+          });
+          dataset.set({
+            headers: headers
+          });
+          dataset.rowCount = schema.count;
+          dfd.resolve(dataset, jqxhr);
+        });
+        return dfd.promise();
+      }
+    }
+  },
+  getRows: function(datasetId, numRows, start) {
+    if (start === undefined) {
+      start = 0;
+    }
+    if (numRows === undefined) {
+      numRows = 10;
+    }
+    var base = this.get('url');
+    var jqxhr = $.ajax({
+      url: base + '.json',
+      dataType: 'jsonp',
+      jsonp: '_callback',
+      cache: true
+      });
+    var dfd = $.Deferred();
+    jqxhr.then(function(results) {
+      dfd.resolve(results.data);
+    });
+    return dfd.promise();
+ }
+});

test/model.test.js

@@ -43,7 +43,109 @@ test('new Dataset', function () {
   });
 });
 
-test('Local Data Sync', function() {
+// TODO: move to fixtures
+var webstoreSchema = {
+  "count": 3, 
+  "data": [
+    {
+      "name": "__id__", 
+      "type": "integer", 
+      "values_url": "/rufuspollock/demo/data/distinct/__id__"
+    }, 
+    {
+      "name": "date", 
+      "type": "text", 
+      "values_url": "/rufuspollock/demo/data/distinct/date"
+    }, 
+    {
+      "name": "geometry", 
+      "type": "text", 
+      "values_url": "/rufuspollock/demo/data/distinct/geometry"
+    }, 
+    {
+      "name": "amount", 
+      "type": "text", 
+      "values_url": "/rufuspollock/demo/data/distinct/amount"
+    }
+  ], 
+  "fields": [
+    {
+      "name": "type"
+    }, 
+    {
+      "name": "name"
+    }, 
+    {
+      "name": "values_url"
+    }
+  ]
+};
+
+webstoreData = {
+  "count": null, 
+  "data": [
+    {
+      "__id__": 1, 
+      "amount": "100", 
+      "date": "2009-01-01", 
+      "geometry": null
+    }, 
+    {
+      "__id__": 2, 
+      "amount": "200", 
+      "date": "2010-01-01", 
+      "geometry": null
+    }, 
+    {
+      "__id__": 3, 
+      "amount": "300", 
+      "date": "2011-01-01", 
+      "geometry": null
+    }
+  ], 
+  "fields": [
+    {
+      "name": "__id__"
+    }, 
+    {
+      "name": "date"
+    }, 
+    {
+      "name": "geometry"
+    }, 
+    {
+      "name": "amount"
+    }
+  ]
+};
+ 
+test('Webstore Backend', function() {
+  stop();
+  var backend = new recline.BackendWebstore({
+    url: 'http://webstore.test.ckan.org/rufuspollock/demo/data'
+  });
+  recline.setBackend(backend);
+  dataset = backend.getDataset();
+
+  var stub = sinon.stub($, 'ajax', function(options) {
+    return {
+      then: function(callback) {
+        callback(webstoreSchema);
+      }
+    }
+  });
+
+  dataset.fetch().then(function(dataset) {
+    equal(['__id__', 'date', 'geometry', 'amount'], dataset.get('headers'));
+    equal(3, dataset.rowCount)
+    // restore mocked method
+    $.ajax.restore();
+    dataset.getRows().then(function(rows) {
+      start();
+      equal(3,rows.length)
+      equal("2009-01-01", rows[0].date);
+    });
+  });
 });
 
 })(this.jQuery);