PanelEditor: Fixes issue changing panel type from graph to stat and thresholds not taking affect after going back to dashboard (#24144)

* PanelEditor: Fixes issue with panel type change and query result reuse

* removed unused imports

* removed unused imports

public/app/features/dashboard/components/PanelEditor/state/actions.test.ts

@@ -88,6 +88,7 @@ describe('panelEditor actions', () => {
 
       expect(dispatchedActions.length).toBe(3);
       expect(dispatchedActions[0].type).toBe(panelModelAndPluginReady.type);
+      expect(sourcePanel.plugin).toEqual(panel.plugin);
     });
 
     it('should discard changes when shouldDiscardChanges is true', async () => {

public/app/features/dashboard/components/PanelEditor/state/actions.ts

@@ -47,6 +47,10 @@ export function panelEditorCleanUp(): ThunkResult<void> {
 
       sourcePanel.restoreModel(modifiedSaveModel);
 
+      // Loaded plugin is not included in the persisted properties
+      // So is not handled by restoreModel
+      sourcePanel.plugin = panel.plugin;
+
       if (panelTypeChanged) {
         dispatch(panelModelAndPluginReady({ panelId: sourcePanel.id, plugin: panel.plugin! }));
       }

public/app/features/dashboard/dashgrid/PanelChrome.tsx

@@ -73,6 +73,7 @@ export class PanelChrome extends PureComponent<Props, State> {
 
     panel.events.on(PanelEvents.refresh, this.onRefresh);
     panel.events.on(PanelEvents.render, this.onRender);
+
     dashboard.panelInitialized(this.props.panel);
 
     // Move snapshot data into the query response
@@ -99,6 +100,15 @@ export class PanelChrome extends PureComponent<Props, State> {
         this.setState({ isFirstLoad: false });
       }
     }
+
+    if (!this.querySubscription) {
+      this.querySubscription = panel
+        .getQueryRunner()
+        .getData()
+        .subscribe({
+          next: data => this.onDataUpdate(data),
+        });
+    }
   }
 
   componentWillUnmount() {
@@ -184,15 +194,7 @@ export class PanelChrome extends PureComponent<Props, State> {
         return;
       }
 
-      const queryRunner = panel.getQueryRunner();
-
-      if (!this.querySubscription) {
-        this.querySubscription = queryRunner.getData().subscribe({
-          next: data => this.onDataUpdate(data),
-        });
-      }
-
-      queryRunner.run({
+      panel.getQueryRunner().run({
         datasource: panel.datasource,
         queries: panel.targets,
         panelId: panel.id,

public/app/features/dashboard/state/DashboardModel.ts

@@ -314,18 +314,10 @@ export class DashboardModel {
   panelInitialized(panel: PanelModel) {
     panel.initialized();
 
-    if (this.panelInEdit === panel) {
-      if (this.panelInEdit.getQueryRunner().getLastResult()) {
-        return;
-      } else {
-        // refresh if panel is in edit mode and there is no last result
-        panel.refresh();
-      }
-    } else {
-      // refresh new panels unless we are in fullscreen / edit mode
-      if (!this.otherPanelInFullscreen(panel)) {
-        panel.refresh();
-      }
+    const lastResult = panel.getQueryRunner().getLastResult();
+
+    if (!this.otherPanelInFullscreen(panel) && !lastResult) {
+      panel.refresh();
     }
   }