Default to timeField if no field is specified in date histogram aggre…

…gation (#215)

grafana/grafana#60238

pkg/opensearch/lucene_handler.go

@@ -44,7 +44,8 @@ func (h *luceneHandler) processQuery(q *Query) error {
 	b := h.ms.Search(interval)
 	b.Size(0)
 	filters := b.Query().Bool().Filter()
-	filters.AddDateRangeFilter(h.client.GetTimeField(), es.DateFormatEpochMS, toMs, fromMs)
+	defaultTimeField := h.client.GetTimeField()
+	filters.AddDateRangeFilter(defaultTimeField, es.DateFormatEpochMS, toMs, fromMs)
 
 	if q.RawQuery != "" {
 		filters.AddQueryStringFilter(q.RawQuery, true)
@@ -59,9 +60,9 @@ func (h *luceneHandler) processQuery(q *Query) error {
 
 	switch {
 	case q.Metrics[0].Type == rawDataType:
-		processRawDataQuery(q, b, h.client.GetTimeField())
+		processRawDataQuery(q, b, defaultTimeField)
 	default:
-		processTimeSeriesQuery(q, b, fromMs, toMs)
+		processTimeSeriesQuery(q, b, fromMs, toMs, defaultTimeField)
 	}
 
 	return nil
@@ -83,7 +84,7 @@ func processRawDataQuery(q *Query, b *es.SearchRequestBuilder, defaultTimeField
 	b.Size(size)
 }
 
-func processTimeSeriesQuery(q *Query, b *es.SearchRequestBuilder, fromMs int64, toMs int64) {
+func processTimeSeriesQuery(q *Query, b *es.SearchRequestBuilder, fromMs int64, toMs int64, defaultTimeField string) {
 	metric := q.Metrics[0]
 	b.Size(metric.Settings.Get("size").MustInt(500))
 	aggBuilder := b.Agg()
@@ -92,7 +93,7 @@ func processTimeSeriesQuery(q *Query, b *es.SearchRequestBuilder, fromMs int64,
 	for _, bucketAgg := range q.BucketAggs {
 		switch bucketAgg.Type {
 		case dateHistType:
-			aggBuilder = addDateHistogramAgg(aggBuilder, bucketAgg, fromMs, toMs)
+			aggBuilder = addDateHistogramAgg(aggBuilder, bucketAgg, fromMs, toMs, defaultTimeField)
 		case histogramType:
 			aggBuilder = addHistogramAgg(aggBuilder, bucketAgg)
 		case filtersType:
@@ -204,8 +205,13 @@ func (h *luceneHandler) executeQueries() (*backend.QueryDataResponse, error) {
 	return rp.getTimeSeries(h.client.GetTimeField())
 }
 
-func addDateHistogramAgg(aggBuilder es.AggBuilder, bucketAgg *BucketAgg, timeFrom, timeTo int64) es.AggBuilder {
-	aggBuilder.DateHistogram(bucketAgg.ID, bucketAgg.Field, func(a *es.DateHistogramAgg, b es.AggBuilder) {
+func addDateHistogramAgg(aggBuilder es.AggBuilder, bucketAgg *BucketAgg, timeFrom, timeTo int64, timeField string) es.AggBuilder {
+	// If no field is specified, use the time field
+	field := bucketAgg.Field
+	if field == "" {
+		field = timeField
+	}
+	aggBuilder.DateHistogram(bucketAgg.ID, field, func(a *es.DateHistogramAgg, b es.AggBuilder) {
 		a.Interval = bucketAgg.Settings.Get("interval").MustString("auto")
 		a.MinDocCount = bucketAgg.Settings.Get("min_doc_count").MustInt(0)
 		a.ExtendedBounds = &es.ExtendedBounds{Min: timeFrom, Max: timeTo}

pkg/opensearch/time_series_query_test.go

@@ -1031,3 +1031,39 @@ func TestTimeSeriesQueryParser(t *testing.T) {
 		})
 	})
 }
+
+func Test_Field_property(t *testing.T) {
+	from := time.Date(2018, 5, 15, 17, 50, 0, 0, time.UTC)
+	to := time.Date(2018, 5, 15, 17, 55, 0, 0, time.UTC)
+	t.Run("Should use timeField from datasource when not specified", func(t *testing.T) {
+		c := newFakeClient(es.Elasticsearch, "2.0.0")
+		_, err := executeTsdbQuery(c, `{
+			"timeField": "@timestamp",
+			"metrics": [{ "type": "count", "id": "1" }],
+			"bucketAggs": [
+				{ "type": "date_histogram", "id": "2", "settings": { "min_doc_count": "1" } }
+			]
+		}`, from, to, 15*time.Second)
+		assert.Nil(t, err)
+
+		sr := c.multisearchRequests[0].Requests[0]
+		dateHistogramAgg := sr.Aggs[0].Aggregation.Aggregation.(*es.DateHistogramAgg)
+		assert.Equal(t, "@timestamp", dateHistogramAgg.Field)
+	})
+
+	t.Run("Should use field from bucket agg when specified", func(t *testing.T) {
+		c := newFakeClient(es.Elasticsearch, "2.0.0")
+		_, err := executeTsdbQuery(c, `{
+				"timeField": "@timestamp",
+				"metrics": [{ "type": "count", "id": "1" }],
+				"bucketAggs": [
+					{ "type": "date_histogram", "id": "2", "field": "some_other_field", "settings": { "min_doc_count": "1" } }
+				]
+			}`, from, to, 15*time.Second)
+
+		assert.Nil(t, err)
+		sr := c.multisearchRequests[0].Requests[0]
+		dateHistogramAgg := sr.Aggs[0].Aggregation.Aggregation.(*es.DateHistogramAgg)
+		assert.Equal(t, "some_other_field", dateHistogramAgg.Field)
+	})
+}