fix: metrics_panel and time range issue introduced earlier today, fixes #7849

public/app/features/panel/metrics_panel_ctrl.ts

@@ -93,6 +93,7 @@ class MetricsPanelCtrl extends PanelCtrl {
     // load datasource service
     this.setTimeQueryStart();
     this.datasourceSrv.get(this.panel.datasource)
+    .then(this.updateTimeRange.bind(this))
     .then(this.issueQueries.bind(this))
     .then(this.handleQueryResult.bind(this))
     .catch(err => {
@@ -119,7 +120,8 @@ class MetricsPanelCtrl extends PanelCtrl {
     this.timing.queryEnd = new Date().getTime();
   }
 
-  updateTimeRange() {
+  updateTimeRange(datasource?) {
+    this.datasource = datasource || this.datasource;
     this.range = this.timeSrv.timeRange();
     this.rangeRaw = this.range.raw;
 
@@ -132,6 +134,8 @@ class MetricsPanelCtrl extends PanelCtrl {
     }
 
     this.calculateInterval();
+
+    return this.datasource;
   };
 
   calculateInterval() {
@@ -194,7 +198,6 @@ class MetricsPanelCtrl extends PanelCtrl {
 
   issueQueries(datasource) {
     this.datasource = datasource;
-    this.updateTimeRange();
 
     if (!this.panel.targets || this.panel.targets.length === 0) {
       return this.$q.when([]);