New chart type : Chord Diagrams (#3013)

superset/assets/javascripts/explore/stores/controls.jsx

@@ -334,11 +334,14 @@ export const controls = {
     type: 'SelectControl',
     multi: true,
     label: 'Columns',
-    mapStateToProps: state => ({
-      choices: (state.datasource) ? state.datasource.gb_cols : [],
-    }),
     default: [],
     description: 'One or many controls to pivot as columns',
+    optionRenderer: c => <ColumnOption column={c} />,
+    valueRenderer: c => <ColumnOption column={c} />,
+    valueKey: 'column_name',
+    mapStateToProps: state => ({
+      options: (state.datasource) ? state.datasource.columns : [],
+    }),
   },
 
   all_columns: {

superset/assets/javascripts/explore/stores/visTypes.js

@@ -1,5 +1,7 @@
 import { D3_TIME_FORMAT_OPTIONS } from './controls';
 
+import * as v from '../validators';
+
 export const sections = {
   druidTimeSeries: {
     label: 'Time',
@@ -635,6 +637,37 @@ const visTypes = {
       },
     },
   },
+  chord: {
+    label: 'Chord Diagram',
+    controlPanelSections: [
+      {
+        label: null,
+        controlSetRows: [
+          ['groupby', 'columns'],
+          ['metric'],
+          ['row_limit', 'y_axis_format'],
+        ],
+      },
+    ],
+    controlOverrides: {
+      y_axis_format: {
+        label: 'Number format',
+        description: 'Choose a number format',
+      },
+      groupby: {
+        label: 'Source',
+        multi: false,
+        validators: [v.nonEmpty],
+        description: 'Choose a source',
+      },
+      columns: {
+        label: 'Target',
+        multi: false,
+        validators: [v.nonEmpty],
+        description: 'Choose a target',
+      },
+    },
+  },
   country_map: {
     label: 'Country Map',
     controlPanelSections: [