fix events search bug when no events

Signed-off-by: Njunotx <junotx@126.com>

pkg/simple/client/events/elasticsearch/clients.go

@@ -98,7 +98,7 @@ func (c *ClientV6) parse(resp *es6api.Response, err error) (*Response, error) {
 		return nil, fmt.Errorf(resp.String())
 	}
 	var r struct {
-		Hits *struct {
+		Hits struct {
 			Total int64               `json:"total"`
 			Hits  jsoniter.RawMessage `json:"hits"`
 		} `json:"hits"`
@@ -128,7 +128,7 @@ func (c *ClientV7) parse(resp *es7api.Response, err error) (*Response, error) {
 		return nil, fmt.Errorf(resp.String())
 	}
 	var r struct {
-		Hits *struct {
+		Hits struct {
 			Total struct {
 				Value int64 `json:"value"`
 			} `json:"total"`

pkg/simple/client/events/elasticsearch/elasticsearch.go

@@ -49,9 +49,12 @@ func (es *elasticsearch) SearchEvents(filter *events.Filter, from, size int64,
 		Index: resolveIndexNames(es.opts.indexPrefix, filter.StartTime, filter.EndTime),
 		Body:  bytes.NewBuffer(body),
 	})
-	if err != nil || resp == nil {
+	if err != nil {
 		return nil, err
 	}
+	if resp == nil || len(resp.Hits.Hits) == 0 {
+		return &events.Events{}, nil
+	}
 
 	var innerHits []struct {
 		*corev1.Event `json:"_source"`
@@ -95,11 +98,17 @@ func (es *elasticsearch) CountOverTime(filter *events.Filter, interval string) (
 		Index: resolveIndexNames(es.opts.indexPrefix, filter.StartTime, filter.EndTime),
 		Body:  bytes.NewBuffer(body),
 	})
-	if err != nil || resp == nil {
+	if err != nil {
 		return nil, err
 	}
+	if resp == nil || resp.Aggregations == nil {
+		return &events.Histogram{}, nil
+	}
 
-	raw := resp.Aggregations[aggName]
+	raw, ok := resp.Aggregations[aggName]
+	if !ok || len(raw) == 0 {
+		return &events.Histogram{}, nil
+	}
 	var agg struct {
 		Buckets []struct {
 			KeyAsString string `json:"key_as_string"`
@@ -142,11 +151,17 @@ func (es *elasticsearch) StatisticsOnResources(filter *events.Filter) (*events.S
 		Index: resolveIndexNames(es.opts.indexPrefix, filter.StartTime, filter.EndTime),
 		Body:  bytes.NewBuffer(body),
 	})
-	if err != nil || resp == nil {
+	if err != nil {
 		return nil, err
 	}
+	if resp == nil || resp.Aggregations == nil {
+		return &events.Statistics{}, nil
+	}
 
-	raw := resp.Aggregations[aggName]
+	raw, ok := resp.Aggregations[aggName]
+	if !ok || len(raw) == 0 {
+		return &events.Statistics{}, nil
+	}
 	var agg struct {
 		Value int64 `json:"value"`
 	}