1 files changed, 73 insertions, 0 deletions
diff --git a/lib/gitlab/prometheus/queries/query_additional_metrics.rb b/lib/gitlab/prometheus/queries/query_additional_metrics.rb
new file mode 100644
index 00000000000..e44be770544
--- /dev/null
+++ b/lib/gitlab/prometheus/queries/query_additional_metrics.rb
@@ -0,0 +1,73 @@
+module Gitlab
+  module Prometheus
+    module Queries
+      module QueryAdditionalMetrics
+        def query_metrics(query_context)
+          query_processor = method(:process_query).curry[query_context]
+
+          groups = matched_metrics.map do |group|
+            metrics = group.metrics.map do |metric|
+              {
+                title: metric.title,
+                weight: metric.weight,
+                y_label: metric.y_label,
+                queries: metric.queries.map(&query_processor).select(&method(:query_with_result))
+              }
+            end
+
+            {
+              group: group.name,
+              priority: group.priority,
+              metrics: metrics.select(&method(:metric_with_any_queries))
+            }
+          end
+
+          groups.select(&method(:group_with_any_metrics))
+        end
+
+        private
+
+        def metric_with_any_queries(metric)
+          metric[:queries]&.count&.> 0
+        end
+
+        def group_with_any_metrics(group)
+          group[:metrics]&.count&.> 0
+        end
+
+        def query_with_result(query)
+          query[:result]&.any? do |item|
+            item&.[](:values)&.any? || item&.[](:value)&.any?
+          end
+        end
+
+        def process_query(context, query)
+          query_with_result = query.dup
+          result =
+            if query.key?(:query_range)
+              client_query_range(query[:query_range] % context, start: context[:timeframe_start], stop: context[:timeframe_end])
+            else
+              client_query(query[:query] % context, time: context[:timeframe_end])
+            end
+          query_with_result[:result] = result&.map(&:deep_symbolize_keys)
+          query_with_result
+        end
+
+        def available_metrics
+          @available_metrics ||= client_label_values || []
+        end
+
+        def matched_metrics
+          result = Gitlab::Prometheus::MetricGroup.all.map do |group|
+            group.metrics.select! do |metric|
+              metric.required_metrics.all?(&available_metrics.method(:include?))
+            end
+            group
+          end
+
+          result.select { |group| group.metrics.any? }
+        end
+      end
+    end
+  end
+end