Elasticsearch: Add time zone setting to Date Histogram aggregation (#40882)

* TimeZonePicker: Allow specifying internal timezones to display

* Elasticsearch: Add time zone setting to Date Histogram aggregation

* rename time_zone to timeZone

* Add tests

* fix typo

* Update packages/grafana-data/src/datetime/timezones.ts

Co-authored-by: Chris Cowan <chris@chriscowan.us>

Co-authored-by: Chris Cowan <chris@chriscowan.us>

pkg/tsdb/elasticsearch/client/models.go

@@ -244,6 +244,7 @@ type DateHistogramAgg struct {
 	ExtendedBounds *ExtendedBounds `json:"extended_bounds"`
 	Format         string          `json:"format"`
 	Offset         string          `json:"offset,omitempty"`
+	TimeZone       string          `json:"time_zone,omitempty"`
 }
 
 // FiltersAggregation represents a filters aggregation

pkg/tsdb/elasticsearch/time_series_query.go

@@ -264,6 +264,12 @@ func addDateHistogramAgg(aggBuilder es.AggBuilder, bucketAgg *BucketAgg, timeFro
 			a.Missing = &missing
 		}
 
+		if timezone, err := bucketAgg.Settings.Get("timeZone").String(); err == nil {
+			if timezone != "utc" {
+				a.TimeZone = timezone
+			}
+		}
+
 		aggBuilder = b
 	})
 

pkg/tsdb/elasticsearch/time_series_query_test.go

@@ -402,6 +402,52 @@ func TestExecuteTimeSeriesQuery(t *testing.T) {
 			require.Equal(t, hAgg.Field, "@timestamp")
 			require.Equal(t, hAgg.Interval, "$__interval")
 			require.Equal(t, hAgg.MinDocCount, 2)
+
+			t.Run("Should not include time_zone when timeZone is utc", func(t *testing.T) {
+				c := newFakeClient("7.0.0")
+				_, err := executeTsdbQuery(c, `{
+					"timeField": "@timestamp",
+					"bucketAggs": [
+						{
+							"id": "2",
+							"type": "date_histogram",
+							"field": "@timestamp",
+							"settings": { 
+								"timeZone": "utc"
+							}
+						}
+					],
+					"metrics": [{"type": "count", "id": "1" }]
+				}`, from, to, 15*time.Second)
+				require.NoError(t, err)
+				sr := c.multisearchRequests[0].Requests[0]
+
+				dateHistogram := sr.Aggs[0].Aggregation.Aggregation.(*es.DateHistogramAgg)
+				require.Empty(t, dateHistogram.TimeZone)
+			})
+
+			t.Run("Should include time_zone when timeZone is not utc", func(t *testing.T) {
+				c := newFakeClient("7.0.0")
+				_, err := executeTsdbQuery(c, `{
+					"timeField": "@timestamp",
+					"bucketAggs": [
+						{
+							"id": "2",
+							"type": "date_histogram",
+							"field": "@timestamp",
+							"settings": { 
+								"timeZone": "America/Los_Angeles"
+							}
+						}
+					],
+					"metrics": [{"type": "count", "id": "1" }]
+				}`, from, to, 15*time.Second)
+				require.NoError(t, err)
+				sr := c.multisearchRequests[0].Requests[0]
+
+				deteHistogram := sr.Aggs[0].Aggregation.Aggregation.(*es.DateHistogramAgg)
+				require.Equal(t, deteHistogram.TimeZone, "America/Los_Angeles")
+			})
 		})
 
 		t.Run("With histogram agg", func(t *testing.T) {
@@ -1163,7 +1209,7 @@ func TestTimeSeriesQueryParser(t *testing.T) {
 				"timeField": "@timestamp",
 				"query": "@metric:cpu",
 				"alias": "{{@hostname}} {{metric}}",
-        "interval": "10m",
+        		"interval": "10m",
 				"metrics": [
 					{
 						"field": "@value",