1 files changed, 78 insertions, 0 deletions
diff --git a/lib/gitlab/database_importers/common_metrics/importer.rb b/lib/gitlab/database_importers/common_metrics/importer.rb
new file mode 100644
index 00000000000..6c61e05674e
--- /dev/null
+++ b/lib/gitlab/database_importers/common_metrics/importer.rb
@@ -0,0 +1,78 @@
+# frozen_string_literal: true
+
+module Gitlab
+  module DatabaseImporters
+    module CommonMetrics
+      class Importer
+        MissingQueryId = Class.new(StandardError)
+
+        attr_reader :content
+
+        def initialize(filename = 'common_metrics.yml')
+          @content = YAML.load_file(Rails.root.join('config', 'prometheus', filename))
+        end
+
+        def execute
+          CommonMetrics::PrometheusMetric.reset_column_information
+
+          process_content do |id, attributes|
+            find_or_build_metric!(id)
+              .update!(**attributes)
+          end
+        end
+
+        private
+
+        def process_content(&blk)
+          content['panel_groups'].map do |group|
+            process_group(group, &blk)
+          end
+        end
+
+        def process_group(group, &blk)
+          attributes = {
+            group: find_group_title_key(group['group'])
+          }
+
+          group['panels'].map do |panel|
+            process_panel(panel, attributes, &blk)
+          end
+        end
+
+        def process_panel(panel, attributes, &blk)
+          attributes = attributes.merge(
+            title: panel['title'],
+            y_label: panel['y_label'])
+
+          panel['metrics'].map do |metric_details|
+            process_metric_details(metric_details, attributes, &blk)
+          end
+        end
+
+        def process_metric_details(metric_details, attributes, &blk)
+          attributes = attributes.merge(
+            legend: metric_details['label'],
+            query: metric_details['query_range'],
+            unit: metric_details['unit'])
+
+          yield(metric_details['id'], attributes)
+        end
+
+        def find_or_build_metric!(id)
+          raise MissingQueryId unless id
+
+          CommonMetrics::PrometheusMetric.common.find_by(identifier: id) ||
+            CommonMetrics::PrometheusMetric.new(common: true, identifier: id)
+        end
+
+        def find_group_title_key(title)
+          CommonMetrics::PrometheusMetricEnums.groups[find_group_title(title)]
+        end
+
+        def find_group_title(title)
+          CommonMetrics::PrometheusMetricEnums.group_titles.invert[title]
+        end
+      end
+    end
+  end
+end