Block graph queries from being queued until annotation datasource promises resolve

public/app/features/annotations/annotations_srv.ts

@@ -8,6 +8,7 @@ import { makeRegions, dedupAnnotations } from './events_processing';
 export class AnnotationsSrv {
   globalAnnotationsPromise: any;
   alertStatesPromise: any;
+  datasourcePromises: any;
 
   /** @ngInject */
   constructor(private $rootScope, private $q, private datasourceSrv, private backendSrv, private timeSrv) {
@@ -18,6 +19,7 @@ export class AnnotationsSrv {
   clearCache() {
     this.globalAnnotationsPromise = null;
     this.alertStatesPromise = null;
+    this.datasourcePromises = null;
   }
 
   getAnnotations(options) {
@@ -90,6 +92,7 @@ export class AnnotationsSrv {
 
     const range = this.timeSrv.timeRange();
     const promises = [];
+    const dsPromises = [];
 
     for (const annotation of dashboard.annotations.list) {
       if (!annotation.enable) {
@@ -99,10 +102,10 @@ export class AnnotationsSrv {
       if (annotation.snapshotData) {
         return this.translateQueryResult(annotation, annotation.snapshotData);
       }
-
+      const datasourcePromise = this.datasourceSrv.get(annotation.datasource);
+      dsPromises.push(datasourcePromise);
       promises.push(
-        this.datasourceSrv
-          .get(annotation.datasource)
+        datasourcePromise
           .then(datasource => {
             // issue query against data source
             return datasource.annotationQuery({
@@ -122,7 +125,7 @@ export class AnnotationsSrv {
           })
       );
     }
-
+    this.datasourcePromises = this.$q.all(dsPromises);
     this.globalAnnotationsPromise = this.$q.all(promises);
     return this.globalAnnotationsPromise;
   }

public/app/plugins/panel/graph/module.ts

@@ -156,7 +156,16 @@ class GraphCtrl extends MetricsPanelCtrl {
       panel: this.panel,
       range: this.range,
     });
+
+    /* Wait for annotationSrv requests to get datasources to
+     * resolve before issuing queries. This allows the annotations
+     * service to fire annotations queries before graph queries
+     * (but not wait for completion). This resolves
+     * issue 11806.
+     */
+    return this.annotationsSrv.datasourcePromises.then(r => {
       return super.issueQueries(datasource);
+    });
   }
 
   zoomOut(evt) {