Add types and comment to reindex function

internal/benchrunner/runners/system/runner.go

@@ -709,6 +709,7 @@ func (r *runner) enrollAgents() error {
 	return nil
 }
 
+// reindexData will read all data generated during the benchmark and will reindex it to the metrisctore
 func (r *runner) reindexData() error {
 	if !r.options.ReindexData {
 		return nil
@@ -719,7 +720,7 @@ func (r *runner) reindexData() error {
 
 	logger.Debug("starting reindexing of data...")
 
-	logger.Debug("gettings orignal mappings...")
+	logger.Debug("getting orignal mappings...")
 	// Get the mapping from the source data stream
 	mappingRes, err := r.options.ESAPI.Indices.GetMapping(
 		r.options.ESAPI.Indices.GetMapping.WithIndex(r.runtimeDataStream),
@@ -789,56 +790,63 @@ func (r *runner) reindexData() error {
 	}
 	defer res.Body.Close()
 
+	type searchRes struct {
+		Error *struct {
+			Reason string `json:"reson"`
+		} `json:"error"`
+		ScrollID string `json:"_scroll_id"`
+		Hits     []struct {
+			ID     string                 `json:"_id"`
+			Source map[string]interface{} `json:"_source"`
+		} `json:"hits"`
+	}
+
 	// Iterate through the search results using the Scroll API
 	for {
-		var sr map[string]interface{}
+		var sr searchRes
 		if err := json.NewDecoder(res.Body).Decode(&sr); err != nil {
 			return fmt.Errorf("error decoding search response: %w", err)
 		}
 
-		resErr, found := sr["error"]
-		if found {
-			errStr := resErr.(map[string]interface{})["reason"].(string)
-			return fmt.Errorf("error searching for documents: %s", errStr)
+		if sr.Error != nil {
+			return fmt.Errorf("error searching for documents: %s", sr.Error.Reason)
 		}
 
-		hits, found := sr["hits"].(map[string]interface{})["hits"].([]interface{})
-		if !found || len(hits) == 0 {
+		if len(sr.Hits) == 0 {
 			break
 		}
 
 		var bulkBodyBuilder strings.Builder
-		for _, hit := range hits {
-			bulkBodyBuilder.WriteString(fmt.Sprintf("{\"index\":{\"_index\":\"%s\",\"_id\":\"%s\"}}\n", indexName, hit.(map[string]interface{})["_id"]))
-			enriched := r.enrichEventWithBenchmarkMetadata(hit.(map[string]interface{})["_source"].(map[string]interface{}))
+		for _, hit := range sr.Hits {
+			bulkBodyBuilder.WriteString(fmt.Sprintf("{\"index\":{\"_index\":\"%s\",\"_id\":\"%s\"}}\n", indexName, hit.ID))
+			enriched := r.enrichEventWithBenchmarkMetadata(hit.Source)
 			src, err := json.Marshal(enriched)
 			if err != nil {
 				return fmt.Errorf("error decoding _source: %w", err)
 			}
 			bulkBodyBuilder.WriteString(fmt.Sprintf("%s\n", string(src)))
 		}
 
-		logger.Debugf("bulk request of %d events...", len(hits))
+		logger.Debugf("bulk request of %d events...", len(sr.Hits))
 
 		bulkRes, err := r.options.ESMetricsAPI.Bulk(strings.NewReader(bulkBodyBuilder.String()))
 		if err != nil {
 			return fmt.Errorf("error performing the bulk index request: %w", err)
 		}
 		bulkRes.Body.Close()
 
-		scrollId, found := sr["_scroll_id"].(string)
-		if !found {
+		if sr.ScrollID == "" {
 			return errors.New("error getting scroll ID")
 		}
 
 		res, err = r.options.ESAPI.Scroll(
-			r.options.ESAPI.Scroll.WithScrollID(scrollId),
+			r.options.ESAPI.Scroll.WithScrollID(sr.ScrollID),
 			r.options.ESAPI.Scroll.WithScroll(time.Minute),
 		)
 		if err != nil {
 			return fmt.Errorf("error executing scroll: %s", err)
 		}
-		defer res.Body.Close()
+		res.Body.Close()
 	}
 
 	logger.Debug("reindexing operation finished")