ElasticSearch: Parse histogram interval as float instead int (#99270)

pkg/tsdb/elasticsearch/client/models.go

@@ -207,10 +207,10 @@ func newAggDef(key string, aggregation *aggContainer) *aggDef {
 
 // HistogramAgg represents a histogram aggregation
 type HistogramAgg struct {
-	Interval    int    `json:"interval,omitempty"`
-	Field       string `json:"field"`
-	MinDocCount int    `json:"min_doc_count"`
-	Missing     *int   `json:"missing,omitempty"`
+	Interval    float64 `json:"interval,omitempty"`
+	Field       string  `json:"field"`
+	MinDocCount int     `json:"min_doc_count"`
+	Missing     *int    `json:"missing,omitempty"`
 }
 
 // DateHistogramAgg represents a date histogram aggregation

pkg/tsdb/elasticsearch/data_query.go

@@ -225,7 +225,7 @@ func addDateHistogramAgg(aggBuilder es.AggBuilder, bucketAgg *BucketAgg, timeFro
 
 func addHistogramAgg(aggBuilder es.AggBuilder, bucketAgg *BucketAgg) es.AggBuilder {
 	aggBuilder.Histogram(bucketAgg.ID, bucketAgg.Field, func(a *es.HistogramAgg, b es.AggBuilder) {
-		a.Interval = stringToIntWithDefaultValue(bucketAgg.Settings.Get("interval").MustString(), 1000)
+		a.Interval = stringToFloatWithDefaultValue(bucketAgg.Settings.Get("interval").MustString(), 1000)
 		a.MinDocCount = bucketAgg.Settings.Get("min_doc_count").MustInt(0)
 
 		if missing, err := bucketAgg.Settings.Get("missing").Int(); err == nil {
@@ -519,3 +519,15 @@ func stringToIntWithDefaultValue(valueStr string, defaultValue int) int {
 	}
 	return value
 }
+
+func stringToFloatWithDefaultValue(valueStr string, defaultValue float64) float64 {
+	value, err := strconv.ParseFloat(valueStr, 64)
+	if err != nil {
+		value = defaultValue
+	}
+	// In our case, 0 is not a valid value and in this case we default to defaultValue
+	if value == 0 {
+		value = defaultValue
+	}
+	return value
+}

pkg/tsdb/elasticsearch/data_query_test.go

@@ -576,10 +576,51 @@ func TestExecuteElasticsearchDataQuery(t *testing.T) {
 			require.Equal(t, firstLevel.Aggregation.Type, "histogram")
 			hAgg := firstLevel.Aggregation.Aggregation.(*es.HistogramAgg)
 			require.Equal(t, hAgg.Field, "bytes")
-			require.Equal(t, hAgg.Interval, 10)
+			require.Equal(t, hAgg.Interval, float64(10))
 			require.Equal(t, hAgg.MinDocCount, 2)
 			require.Equal(t, *hAgg.Missing, 5)
 		})
+		t.Run("With histogram agg with decimal interval", func(t *testing.T) {
+			c := newFakeClient()
+			_, err := executeElasticsearchDataQuery(c, `{
+				"bucketAggs": [
+					{
+						"id": "3",
+						"type": "histogram",
+						"field": "bytes",
+						"settings": { "interval": "5.5", "min_doc_count": 2, "missing": 5 }
+					}
+				],
+				"metrics": [{"type": "count", "id": "1" }]
+			}`, from, to)
+			require.NoError(t, err)
+			sr := c.multisearchRequests[0].Requests[0]
+
+			firstLevel := sr.Aggs[0]
+			hAgg := firstLevel.Aggregation.Aggregation.(*es.HistogramAgg)
+			require.Equal(t, hAgg.Interval, 5.5)
+		})
+
+		t.Run("With histogram agg with invalid interval", func(t *testing.T) {
+			c := newFakeClient()
+			_, err := executeElasticsearchDataQuery(c, `{
+				"bucketAggs": [
+					{
+						"id": "3",
+						"type": "histogram",
+						"field": "bytes",
+						"settings": { "interval": "5,5", "min_doc_count": 2, "missing": 5 }
+					}
+				],
+				"metrics": [{"type": "count", "id": "1" }]
+			}`, from, to)
+			require.NoError(t, err)
+			sr := c.multisearchRequests[0].Requests[0]
+
+			firstLevel := sr.Aggs[0]
+			hAgg := firstLevel.Aggregation.Aggregation.(*es.HistogramAgg)
+			require.Equal(t, hAgg.Interval, float64(1000))
+		})
 
 		t.Run("With histogram (from frontend tests)", func(t *testing.T) {
 			c := newFakeClient()
@@ -602,7 +643,7 @@ func TestExecuteElasticsearchDataQuery(t *testing.T) {
 			require.Equal(t, firstLevel.Aggregation.Type, "histogram")
 			hAgg := firstLevel.Aggregation.Aggregation.(*es.HistogramAgg)
 			require.Equal(t, hAgg.Field, "bytes")
-			require.Equal(t, hAgg.Interval, 10)
+			require.Equal(t, hAgg.Interval, float64(10))
 			require.Equal(t, hAgg.MinDocCount, 2)
 		})