[Discover] Modify columns and sort when switching index pattern

src/plugins/discover/public/application/angular/discover.js

@@ -253,6 +253,11 @@ function discoverController($element, $route, $scope, $timeout, $window, Promise
 
     if (!_.isEqual(newStatePartial, oldStatePartial)) {
       $scope.$evalAsync(async () => {
+        if (oldStatePartial.index !== newStatePartial.index) {
+          //in case of index switch the route has currently to be reloaded, legacy
+          return;
+        }
+
         $scope.state = { ...newState };
 
         // detect changes that should trigger fetching of new data
@@ -277,8 +282,20 @@ function discoverController($element, $route, $scope, $timeout, $window, Promise
   });
 
   $scope.setIndexPattern = async (id) => {
-    await replaceUrlAppState({ index: id });
-    $route.reload();
+    const nextIndexPattern = await indexPatterns.get(id);
+    if (nextIndexPattern) {
+      const nextColumns = $scope.state.columns.filter((column) =>
+        nextIndexPattern.fields.getByName(column)
+      );
+      const nextSort = getSortArray($scope.state.sort, nextIndexPattern);
+      const nextState = {
+        index: id,
+        columns: nextColumns.length ? nextColumns : ['_source'],
+        sort: nextSort,
+      };
+      await replaceUrlAppState(nextState);
+      $route.reload();
+    }
   };
 
   // update data source when filters update