Dashboard: Fix navigation from one SoloPanelPage to another one (#28578)

* Add test for SoloPanelPage.tsx

* Fix navigation from one SoloPanelPage to another one

The panel did not update because it assumed that the dashboard was already
fully loaded.

public/app/features/dashboard/containers/SoloPanelPage.test.tsx

+import React from 'react';
+import { render, screen } from '@testing-library/react';
+import { SoloPanelPage, Props } from './SoloPanelPage';
+import { Props as DashboardPanelProps } from '../dashgrid/DashboardPanel';
+import { DashboardModel } from '../state';
+import { DashboardRouteInfo } from 'app/types';
+
+jest.mock('app/features/dashboard/components/DashboardSettings/SettingsCtrl', () => ({}));
+jest.mock('app/features/dashboard/dashgrid/DashboardPanel', () => {
+  class DashboardPanel extends React.Component<DashboardPanelProps> {
+    render() {
+      // In this test we only check whether a new panel has arrived in the props
+      return <>{this.props.panel?.title}</>;
+    }
+  }
+
+  return { DashboardPanel };
+});
+
+interface ScenarioContext {
+  dashboard?: DashboardModel | null;
+  secondaryDashboard?: DashboardModel | null;
+  setDashboard: (overrides?: any, metaOverrides?: any) => void;
+  setSecondaryDashboard: (overrides?: any, metaOverrides?: any) => void;
+  mount: (propOverrides?: Partial<Props>) => void;
+  rerender: (propOverrides?: Partial<Props>) => void;
+  setup: (fn: () => void) => void;
+}
+
+function getTestDashboard(overrides?: any, metaOverrides?: any): DashboardModel {
+  const data = Object.assign(
+    {
+      title: 'My dashboard',
+      panels: [
+        {
+          id: 1,
+          type: 'graph',
+          title: 'My graph',
+          gridPos: { x: 0, y: 0, w: 1, h: 1 },
+        },
+      ],
+    },
+    overrides
+  );
+
+  const meta = Object.assign({ canSave: true, canEdit: true }, metaOverrides);
+  return new DashboardModel(data, meta);
+}
+
+function soloPanelPageScenario(description: string, scenarioFn: (ctx: ScenarioContext) => void) {
+  describe(description, () => {
+    let setupFn: () => void;
+
+    const ctx: ScenarioContext = {
+      setup: fn => {
+        setupFn = fn;
+      },
+      setDashboard: (overrides?: any, metaOverrides?: any) => {
+        ctx.dashboard = getTestDashboard(overrides, metaOverrides);
+      },
+      setSecondaryDashboard: (overrides?: any, metaOverrides?: any) => {
+        ctx.secondaryDashboard = getTestDashboard(overrides, metaOverrides);
+      },
+      mount: (propOverrides?: Partial<Props>) => {
+        const props: Props = {
+          urlSlug: 'my-dash',
+          $scope: {},
+          urlUid: '11',
+          urlPanelId: '1',
+          $injector: {},
+          routeInfo: DashboardRouteInfo.Normal,
+          initDashboard: jest.fn(),
+          dashboard: null,
+        };
+
+        Object.assign(props, propOverrides);
+
+        ctx.dashboard = props.dashboard;
+        let { rerender } = render(<SoloPanelPage {...props} />);
+        // prop updates will be submitted by rerendering the same component with different props
+        ctx.rerender = (newProps: Partial<Props>) => {
+          Object.assign(props, newProps);
+          rerender(<SoloPanelPage {...props} />);
+        };
+      },
+      rerender: () => {
+        // will be replaced while mount() is called
+      },
+    };
+
+    beforeEach(() => {
+      setupFn();
+    });
+
+    scenarioFn(ctx);
+  });
+}
+
+describe('SoloPanelPage', () => {
+  soloPanelPageScenario('Given initial state', ctx => {
+    ctx.setup(() => {
+      ctx.mount();
+    });
+
+    it('Should render nothing', () => {
+      expect(screen.queryByText(/Loading/)).not.toBeNull();
+    });
+  });
+
+  soloPanelPageScenario('Dashboard init completed ', ctx => {
+    ctx.setup(() => {
+      ctx.mount();
+      ctx.setDashboard();
+      expect(ctx.dashboard).not.toBeNull();
+      // the componentDidMount will change the dashboard prop to the new dashboard
+      // emulate this by rerendering with new props
+      ctx.rerender({ dashboard: ctx.dashboard });
+    });
+
+    it('Should render dashboard grid', async () => {
+      // check if the panel title has arrived in the DashboardPanel mock
+      expect(screen.queryByText(/My graph/)).not.toBeNull();
+    });
+  });
+
+  soloPanelPageScenario('When user navigates to other SoloPanelPage', ctx => {
+    ctx.setup(() => {
+      ctx.mount();
+      ctx.setDashboard({ uid: 1, panels: [{ id: 1, type: 'graph', title: 'Panel 1' }] });
+      ctx.setSecondaryDashboard({ uid: 2, panels: [{ id: 1, type: 'graph', title: 'Panel 2' }] });
+    });
+
+    it('Should show other graph', () => {
+      // check that the title in the DashboardPanel has changed
+      ctx.rerender({ dashboard: ctx.dashboard });
+      expect(screen.queryByText(/Panel 1/)).not.toBeNull();
+      ctx.rerender({ dashboard: ctx.secondaryDashboard });
+      expect(screen.queryByText(/Panel 1/)).toBeNull();
+      expect(screen.queryByText(/Panel 2/)).not.toBeNull();
+    });
+  });
+});

public/app/features/dashboard/containers/SoloPanelPage.tsx

@@ -13,7 +13,7 @@ import { initDashboard } from '../state/initDashboard';
 import { StoreState, DashboardRouteInfo } from 'app/types';
 import { PanelModel, DashboardModel } from 'app/features/dashboard/state';
 
-interface Props {
+export interface Props {
   urlPanelId: string;
   urlUid?: string;
   urlSlug?: string;
@@ -25,7 +25,7 @@ interface Props {
   dashboard: DashboardModel | null;
 }
 
-interface State {
+export interface State {
   panel: PanelModel | null;
   notFound: boolean;
 }
@@ -57,8 +57,8 @@ export class SoloPanelPage extends Component<Props, State> {
       return;
     }
 
-    // we just got the dashboard!
-    if (!prevProps.dashboard) {
+    // we just got a new dashboard
+    if (!prevProps.dashboard || prevProps.dashboard.uid !== dashboard.uid) {
       const panelId = parseInt(urlPanelId, 10);
 
       // need to expand parent row if this panel is inside a row