Added configured? method to PrometheusAdapter

app/models/clusters/applications/prometheus.rb

@@ -91,6 +91,10 @@ module Clusters
         # we need to silence the exceptions
       end
 
+      def configured?
+        kube_client.present? && available?
+      end
+
       private
 
       def disable_prometheus_integration

app/models/concerns/prometheus_adapter.rb

@@ -16,6 +16,14 @@ module PrometheusAdapter
       raise NotImplementedError
     end
 
+    # This is a light-weight check if a prometheus client is properly configured.
+    def configured?
+      raise NotImplemented
+    end
+
+    # This is a heavy-weight check if a prometheus is properly configured and accesible from GitLab.
+    # This actually sends a request to an external service and often it could take a long time,
+    # Please consider using `configured?` instead if the process is running on unicorn/puma threads.
     def can_query?
       prometheus_client.present?
     end

app/models/environment.rb

@@ -193,11 +193,11 @@ class Environment < ApplicationRecord
   end
 
   def has_metrics?
-    available? && prometheus_adapter&.can_query?
+    available? && prometheus_adapter&.configured?
   end
 
   def metrics
-    prometheus_adapter.query(:environment, self) if has_metrics?
+    prometheus_adapter.query(:environment, self) if has_metrics? && prometheus_adapter.can_query?
   end
 
   def prometheus_status

app/models/project_services/prometheus_service.rb

@@ -95,6 +95,10 @@ class PrometheusService < MonitoringService
     self_monitoring_project? && internal_prometheus_url?
   end
 
+  def configured?
+    should_return_client?
+  end
+
   private
 
   def self_monitoring_project?