Merge branch '5029-support-cluster-metrics-ce' into 'master'

Refactoring changes to support cluster metrics in EE

Closes #42820

See merge request gitlab-org/gitlab-ce!17336

8 files changed, 53 insertions, 16 deletions

diff --git a/lib/gitlab/prometheus/additional_metrics_parser.rb b/lib/gitlab/prometheus/additional_metrics_parser.rb
index cb95daf2260..bb1172f82a1 100644
--- a/lib/gitlab/prometheus/additional_metrics_parser.rb
+++ b/lib/gitlab/prometheus/additional_metrics_parser.rb
@@ -1,10 +1,12 @@
 module Gitlab
   module Prometheus
     module AdditionalMetricsParser
+      CONFIG_ROOT = 'config/prometheus'.freeze
+      MUTEX = Mutex.new
       extend self
 
-      def load_groups_from_yaml
-        additional_metrics_raw.map(&method(:group_from_entry))
+      def load_groups_from_yaml(file_name = 'additional_metrics.yml')
+        yaml_metrics_raw(file_name).map(&method(:group_from_entry))
       end
 
       private
@@ -22,13 +24,20 @@ module Gitlab
         MetricGroup.new(entry).tap(&method(:validate!))
       end
 
-      def additional_metrics_raw
-        load_yaml_file&.map(&:deep_symbolize_keys).freeze
+      def yaml_metrics_raw(file_name)
+        load_yaml_file(file_name)&.map(&:deep_symbolize_keys).freeze
       end
 
-      def load_yaml_file
-        @loaded_yaml_file ||= YAML.load_file(Rails.root.join('config/prometheus/additional_metrics.yml'))
+      # rubocop:disable Gitlab/ModuleWithInstanceVariables
+      def load_yaml_file(file_name)
+        return YAML.load_file(Rails.root.join(CONFIG_ROOT, file_name)) if Rails.env.development?
+
+        MUTEX.synchronize do
+          @loaded_yaml_cache ||= {}
+          @loaded_yaml_cache[file_name] ||= YAML.load_file(Rails.root.join(CONFIG_ROOT, file_name))
+        end
       end
+      # rubocop:enable Gitlab/ModuleWithInstanceVariables
     end
   end
 end
diff --git a/lib/gitlab/prometheus/queries/additional_metrics_deployment_query.rb b/lib/gitlab/prometheus/queries/additional_metrics_deployment_query.rb
index 972ab75d1d5..e677ec84cd4 100644
--- a/lib/gitlab/prometheus/queries/additional_metrics_deployment_query.rb
+++ b/lib/gitlab/prometheus/queries/additional_metrics_deployment_query.rb
@@ -4,7 +4,7 @@ module Gitlab
       class AdditionalMetricsDeploymentQuery < BaseQuery
         include QueryAdditionalMetrics
 
-        def query(environment_id, deployment_id)
+        def query(deployment_id)
           Deployment.find_by(id: deployment_id).try do |deployment|
             query_metrics(
               deployment.project,
diff --git a/lib/gitlab/prometheus/queries/base_query.rb b/lib/gitlab/prometheus/queries/base_query.rb
index c60828165bd..29cab6e9c15 100644
--- a/lib/gitlab/prometheus/queries/base_query.rb
+++ b/lib/gitlab/prometheus/queries/base_query.rb
@@ -20,6 +20,10 @@ module Gitlab
         def query(*args)
           raise NotImplementedError
         end
+
+        def self.transform_reactive_result(result)
+          result
+        end
       end
     end
   end
diff --git a/lib/gitlab/prometheus/queries/deployment_query.rb b/lib/gitlab/prometheus/queries/deployment_query.rb
index 6e6da593178..c2626581897 100644
--- a/lib/gitlab/prometheus/queries/deployment_query.rb
+++ b/lib/gitlab/prometheus/queries/deployment_query.rb
@@ -2,7 +2,7 @@ module Gitlab
   module Prometheus
     module Queries
       class DeploymentQuery < BaseQuery
-        def query(environment_id, deployment_id)
+        def query(deployment_id)
           Deployment.find_by(id: deployment_id).try do |deployment|
             environment_slug = deployment.environment.slug
 
@@ -25,6 +25,11 @@ module Gitlab
             }
           end
         end
+
+        def self.transform_reactive_result(result)
+          result[:metrics] = result.delete :data
+          result
+        end
       end
     end
   end
diff --git a/lib/gitlab/prometheus/queries/environment_query.rb b/lib/gitlab/prometheus/queries/environment_query.rb
index 1d17d3cfd56..b62910c8de6 100644
--- a/lib/gitlab/prometheus/queries/environment_query.rb
+++ b/lib/gitlab/prometheus/queries/environment_query.rb
@@ -19,6 +19,11 @@ module Gitlab
             }
           end
         end
+
+        def self.transform_reactive_result(result)
+          result[:metrics] = result.delete :data
+          result
+        end
       end
     end
   end
diff --git a/lib/gitlab/prometheus/queries/matched_metrics_query.rb b/lib/gitlab/prometheus/queries/matched_metric_query.rb
index 5710ad47c1a..d920e9a749f 100644
--- a/lib/gitlab/prometheus/queries/matched_metrics_query.rb
+++ b/lib/gitlab/prometheus/queries/matched_metric_query.rb
@@ -1,7 +1,7 @@
 module Gitlab
   module Prometheus
     module Queries
-      class MatchedMetricsQuery < BaseQuery
+      class MatchedMetricQuery < BaseQuery
         MAX_QUERY_ITEMS = 40.freeze
 
         def query
diff --git a/lib/gitlab/prometheus/queries/query_additional_metrics.rb b/lib/gitlab/prometheus/queries/query_additional_metrics.rb
index 0c280dc9a3c..aad76e335af 100644
--- a/lib/gitlab/prometheus/queries/query_additional_metrics.rb
+++ b/lib/gitlab/prometheus/queries/query_additional_metrics.rb
@@ -3,9 +3,16 @@ module Gitlab
     module Queries
       module QueryAdditionalMetrics
         def query_metrics(project, query_context)
+          matched_metrics(project).map(&query_group(query_context))
+            .select(&method(:group_with_any_metrics))
+        end
+
+        protected
+
+        def query_group(query_context)
           query_processor = method(:process_query).curry[query_context]
 
-          groups = matched_metrics(project).map do |group|
+          lambda do |group|
             metrics = group.metrics.map do |metric|
               {
                 title: metric.title,
@@ -21,8 +28,6 @@ module Gitlab
               metrics: metrics.select(&method(:metric_with_any_queries))
             }
           end
-
-          groups.select(&method(:group_with_any_metrics))
         end
 
         private
@@ -72,12 +77,17 @@ module Gitlab
         end
 
         def common_query_context(environment, timeframe_start:, timeframe_end:)
-          {
-            timeframe_start: timeframe_start,
-            timeframe_end: timeframe_end,
+          base_query_context(timeframe_start, timeframe_end).merge({
             ci_environment_slug: environment.slug,
             kube_namespace: environment.project.deployment_platform&.actual_namespace || '',
             environment_filter: %{container_name!="POD",environment="#{environment.slug}"}
+          })
+        end
+
+        def base_query_context(timeframe_start, timeframe_end)
+          {
+            timeframe_start: timeframe_start,
+            timeframe_end: timeframe_end
           }
         end
       end
diff --git a/lib/gitlab/prometheus_client.rb b/lib/gitlab/prometheus_client.rb
index 659021c9ac9..b66253a10e0 100644
--- a/lib/gitlab/prometheus_client.rb
+++ b/lib/gitlab/prometheus_client.rb
@@ -57,7 +57,11 @@ module Gitlab
     rescue OpenSSL::SSL::SSLError
       raise PrometheusClient::Error, "#{rest_client.url} contains invalid SSL data"
     rescue RestClient::ExceptionWithResponse => ex
-      handle_exception_response(ex.response)
+      if ex.response
+        handle_exception_response(ex.response)
+      else
+        raise PrometheusClient::Error, "Network connection error"
+      end
     rescue RestClient::Exception
       raise PrometheusClient::Error, "Network connection error"
     end