AdminClient creation error handling fix

1. AdminClient error logging added (#1136)
2. MetricsService error handling fixed

kafka-ui-api/src/main/java/com/provectus/kafka/ui/service/AdminClientServiceImpl.java

@@ -38,7 +38,10 @@ public class AdminClientServiceImpl implements AdminClientService, Closeable {
           .put(AdminClientConfig.BOOTSTRAP_SERVERS_CONFIG, cluster.getBootstrapServers());
       properties.put(AdminClientConfig.REQUEST_TIMEOUT_MS_CONFIG, clientTimeout);
       return AdminClient.create(properties);
-    }).flatMap(ReactiveAdminClient::create);
+    })
+        .flatMap(ReactiveAdminClient::create)
+        .onErrorMap(th -> new IllegalStateException(
+            "Error while creating AdminClient for Cluster " + cluster.getName(), th));
   }
 
   @Override

kafka-ui-api/src/main/java/com/provectus/kafka/ui/service/MetricsService.java

@@ -31,7 +31,7 @@ public class MetricsService {
 
   private Mono<MetricsCache.Metrics> getMetrics(KafkaCluster cluster) {
     return adminClientService.get(cluster).flatMap(ac ->
-        ac.describeCluster().flatMap(description ->
+            ac.describeCluster().flatMap(description ->
                 Mono.zip(
                     List.of(
                         jmxClusterUtil.getBrokerMetrics(cluster, description.getNodes()),
@@ -52,11 +52,11 @@ public class MetricsService {
                             .topicConfigs((Map<String, List<ConfigEntry>>) results[4])
                             .topicDescriptions((Map<String, TopicDescription>) results[5])
                             .build()
-                ))
-            .doOnError(e ->
-                log.error("Failed to collect cluster {} info", cluster.getName(), e))
-            .onErrorResume(
-                e -> Mono.just(MetricsCache.empty().toBuilder().lastKafkaException(e).build())));
+                )))
+        .doOnError(e ->
+            log.error("Failed to collect cluster {} info", cluster.getName(), e))
+        .onErrorResume(
+            e -> Mono.just(MetricsCache.empty().toBuilder().lastKafkaException(e).build()));
   }
 
   private Mono<InternalLogDirStats> getLogDirInfo(KafkaCluster cluster, ReactiveAdminClient c) {