[receiver/kafkametrics] Fix the issue with incorrect cluster admin initialization in consumer scraper

Author: yurytaranau

.chloggen/kafkametricsreceiver-cluster-admin-init.yaml

@@ -0,0 +1,27 @@
+# Use this changelog template to create an entry for release notes.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: bug_fix
+
+# The name of the component, or a single word describing the area of concern, (e.g. filelogreceiver)
+component: kafkametricsreceiver
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Fix incorrect cluster admin initialization in consumer scraper
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [36818]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext:
+
+# If your change doesn't affect end users or the exported elements of any package,
+# you should instead start your pull request title with [chore] or use the "Skip Changelog" label.
+# Optional: The change log or logs in which this entry should be included.
+# e.g. '[user]' or '[user, api]'
+# Include 'user' if the change is relevant to end users.
+# Include 'api' if there is a change to a library API.
+# Default: '[user]'
+change_logs: []

receiver/kafkametricsreceiver/consumer_scraper.go

@@ -49,15 +49,18 @@ func (s *consumerScraper) scrape(context.Context) (pmetric.Metrics, error) {
 		if err != nil {
 			return pmetric.Metrics{}, fmt.Errorf("failed to create client in consumer scraper: %w", err)
 		}
-		clusterAdmin, err := newClusterAdmin(s.config.Brokers, s.saramaConfig)
+		s.client = client
+	}
+
+	if s.clusterAdmin == nil {
+		admin, err := newClusterAdmin(s.config.Brokers, s.saramaConfig)
 		if err != nil {
-			if client != nil {
-				_ = client.Close()
+			if s.client != nil {
+				_ = s.client.Close()
 			}
 			return pmetric.Metrics{}, fmt.Errorf("failed to create cluster admin in consumer scraper: %w", err)
 		}
-		s.client = client
-		s.clusterAdmin = clusterAdmin
+		s.clusterAdmin = admin
 	}
 
 	cgs, listErr := s.clusterAdmin.ListConsumerGroups()