add kube_namespace and standardize common variables for additional metrics queries

lib/gitlab/prometheus/queries/additional_metrics_deployment_query.rb

@@ -6,12 +6,12 @@ module Gitlab
 
         def query(deployment_id)
           Deployment.find_by(id: deployment_id).try do |deployment|
-            query_context = {
-              environment_slug: deployment.environment.slug,
-              environment_filter: %{container_name!="POD",environment="#{deployment.environment.slug}"},
+            query_context = common_query_context(deployment.environment).merge(
+              {
                 timeframe_start: (deployment.created_at - 30.minutes).to_f,
                 timeframe_end: (deployment.created_at + 30.minutes).to_f
               }
+            )
 
             query_metrics(query_context)
           end

lib/gitlab/prometheus/queries/additional_metrics_environment_query.rb

@@ -6,12 +6,12 @@ module Gitlab
 
         def query(environment_id)
           Environment.find_by(id: environment_id).try do |environment|
-            query_context = {
-              environment_slug: environment.slug,
-              environment_filter: %{container_name!="POD",environment="#{environment.slug}"},
+            query_context = common_query_context(environment).merge(
+              {
                 timeframe_start: 8.hours.ago.to_f,
                 timeframe_end: Time.now.to_f
               }
+            )
 
             query_metrics(query_context)
           end

lib/gitlab/prometheus/queries/query_additional_metrics.rb

@@ -67,6 +67,18 @@ module Gitlab
 
           result.select { |group| group.metrics.any? }
         end
+
+        def common_query_context(environment)
+          variables = {
+            ci_environment_slug: environment.slug,
+            kube_namespace: environment.project.kubernetes_service.actual_namespace,
+          }.flat_map { |k, v| [[k, v], [k.upcase, v]] }.to_h
+
+          macros = {
+            environment_filter: %{container_name!="POD",environment="#{environment.slug}"}
+          }
+          variables.merge(macros)
+        end
       end
     end
   end