Datasources: Emit event on dashboard load with queries info (#52052)

Co-authored-by: Levente Balogh <balogh.levente.hu@gmail.com>
Co-authored-by: Andres Martinez <andres.martinez@grafana.com>

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

@@ -1,6 +1,7 @@
-import { locationUtil, setWeekStart } from '@grafana/data';
+import { DataQuery, locationUtil, setWeekStart, DashboardLoadedEvent } from '@grafana/data';
 import { config, isFetchError, locationService } from '@grafana/runtime';
 import { notifyApp } from 'app/core/actions';
+import appEvents from 'app/core/app_events';
 import { createErrorNotification } from 'app/core/copy/appNotification';
 import { backendSrv } from 'app/core/services/backend_srv';
 import { keybindingSrv } from 'app/core/services/keybindingSrv';
@@ -17,6 +18,7 @@ import { initVariablesTransaction } from '../../variables/state/actions';
 import { getIfExistsLastKey } from '../../variables/state/selectors';
 
 import { DashboardModel } from './DashboardModel';
+import { PanelModel } from './PanelModel';
 import { emitDashboardViewEvent } from './analyticsProcessor';
 import { dashboardInitCompleted, dashboardInitFailed, dashboardInitFetching, dashboardInitServices } from './reducers';
 
@@ -106,6 +108,28 @@ async function fetchDashboard(
   }
 }
 
+const getQueriesByDatasource = (
+  panels: PanelModel[],
+  queries: { [datasourceId: string]: DataQuery[] } = {}
+): { [datasourceId: string]: DataQuery[] } => {
+  panels.forEach((panel) => {
+    if (panel.panels) {
+      getQueriesByDatasource(panel.panels, queries);
+    } else {
+      panel.targets.forEach((target) => {
+        if (target.datasource?.type) {
+          if (queries[target.datasource.type]) {
+            queries[target.datasource.type].push(target);
+          } else {
+            queries[target.datasource.type] = [target];
+          }
+        }
+      });
+    }
+  });
+  return queries;
+};
+
 /**
  * This action (or saga) does everything needed to bootstrap a dashboard & dashboard model.
  * First it handles the process of fetching the dashboard, correcting the url if required (causing redirects/url updates)
@@ -213,6 +237,17 @@ export function initDashboard(args: InitDashboardArgs): ThunkResult<void> {
       setWeekStart(config.bootData.user.weekStart);
     }
 
+    // Propagate an app-wide event about the dashboard being loaded
+    appEvents.publish(
+      new DashboardLoadedEvent({
+        dashboardId: dashboard.uid,
+        orgId: storeState.user.orgId,
+        userId: storeState.user.user?.id,
+        grafanaVersion: config.buildInfo.version,
+        queries: getQueriesByDatasource(dashboard.panels),
+      })
+    );
+
     // yay we are done
     dispatch(dashboardInitCompleted(dashboard));
   };