fix: compatibility with Grafana 7.4

src/libs/polygrafill/funcs.ts

@@ -8,6 +8,12 @@ import { Emitter } from 'grafana/app/core/utils/emitter';
 // This method detects this behaviour and return true
 // only for new Grafana versions.
 export function hasAppEventCompatibleEmitter(emitter: Emitter): boolean {
+  // Grafana 7.4 has new event bus for Angular plugins. It is has a 'subscribe' method.
+  let emitterProto = Object.getPrototypeOf(emitter);
+  if (Object.prototype.hasOwnProperty.call(emitterProto, 'subscribe')) {
+    return true;
+  }
+
   let receiveEvents = 0;
   let eventId: any = { name: 'non-existed-event-id' };
   let eventId2: any = { name: 'non-existed-event-id-2' };

src/module.ts

@@ -72,7 +72,6 @@ class StatusHeatmapCtrl extends MetricsPanelCtrl {
   bucketMatrixPager: BucketMatrixPager;
 
   graph: any;
-  discreteHelper: ColorModeDiscrete;
   opacityScales: any = [];
   colorModes: any = [];
   colorSchemes: any = [];

src/rendering.ts

@@ -1,9 +1,9 @@
 import _ from 'lodash';
 import $ from 'jquery';
 
+// TODO moment is used instead of @grafana/data to run in 6.2 and earlier.
 /* eslint-disable id-blacklist, no-restricted-imports, @typescript-eslint/ban-types */
-// import moment from 'moment';
-import { toUtc } from '@grafana/data';
+import moment from 'moment';
 
 import kbn from 'grafana/app/core/utils/kbn';
 import { appEvents, contextSrv } from 'grafana/app/core/core';
@@ -643,9 +643,10 @@ export class StatusmapRenderer {
         Math.max(this.selection.x1, this.selection.x2) - this.yAxisWidth - this.xGridSize / 2
       );
 
+      // TODO use toUtc method from moment wrapper in @grafana/data
       this.ctrl.timeSrv.setTime({
-        from: toUtc(timeFrom),
-        to: toUtc(timeTo),
+        from: moment.utc(timeFrom),
+        to: moment.utc(timeTo),
       });
     }