Move importers to lib folder

This moves our metric importers into the lib folder. This will allow
them to be autoloaded instead of having to explicitly require them.

10 files changed, 153 insertions, 142 deletions

diff --git a/db/importers/common_metrics.rb b/db/importers/common_metrics.rb
deleted file mode 100644
index 411d366ef83..00000000000
--- a/db/importers/common_metrics.rb
+++ /dev/null
@@ -1,17 +0,0 @@
-require_relative './common_metrics/importer'
-require_relative './common_metrics/prometheus_metric'
-require_relative './common_metrics/prometheus_metric_enums'
-
-require Rails.root.join('ee', 'db', 'importers', 'common_metrics') if Gitlab.ee?
-
-module Importers
-  module CommonMetrics
-  end
-
-  # Patch to preserve old CommonMetricsImporter api
-  module CommonMetricsImporter
-    def self.new(*args)
-      Importers::CommonMetrics::Importer.new(*args)
-    end
-  end
-end
diff --git a/db/importers/common_metrics/importer.rb b/db/importers/common_metrics/importer.rb
deleted file mode 100644
index 24149fbbea6..00000000000
--- a/db/importers/common_metrics/importer.rb
+++ /dev/null
@@ -1,76 +0,0 @@
-# frozen_string_literal: true
-
-module Importers
-  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
-        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
-
-        PrometheusMetric.common.find_by(identifier: id) ||
-          PrometheusMetric.new(common: true, identifier: id)
-      end
-
-      def find_group_title_key(title)
-        PrometheusMetricEnums.groups[find_group_title(title)]
-      end
-
-      def find_group_title(title)
-        PrometheusMetricEnums.group_titles.invert[title]
-      end
-    end
-  end
-end
diff --git a/db/importers/common_metrics/prometheus_metric.rb b/db/importers/common_metrics/prometheus_metric.rb
deleted file mode 100644
index 9149549c750..00000000000
--- a/db/importers/common_metrics/prometheus_metric.rb
+++ /dev/null
@@ -1,8 +0,0 @@
-module Importers
-  module CommonMetrics
-    class PrometheusMetric < ActiveRecord::Base
-      enum group: PrometheusMetricEnums.groups
-      scope :common, -> { where(common: true) }
-    end
-  end
-end
diff --git a/db/importers/common_metrics/prometheus_metric_enums.rb b/db/importers/common_metrics/prometheus_metric_enums.rb
deleted file mode 100644
index 50a1081a629..00000000000
--- a/db/importers/common_metrics/prometheus_metric_enums.rb
+++ /dev/null
@@ -1,36 +0,0 @@
-module Importers
-  module CommonMetrics
-    module PrometheusMetricEnums
-      def self.groups
-        {
-          # built-in groups
-          nginx_ingress_vts: -1,
-          ha_proxy: -2,
-          aws_elb: -3,
-          nginx: -4,
-          kubernetes: -5,
-          nginx_ingress: -6,
-
-          # custom groups
-          business: 0,
-          response: 1,
-          system: 2
-        }
-      end
-
-      def self.group_titles
-        {
-          business: _('Business metrics (Custom)'),
-          response: _('Response metrics (Custom)'),
-          system: _('System metrics (Custom)'),
-          nginx_ingress_vts: _('Response metrics (NGINX Ingress VTS)'),
-          nginx_ingress: _('Response metrics (NGINX Ingress)'),
-          ha_proxy: _('Response metrics (HA Proxy)'),
-          aws_elb: _('Response metrics (AWS ELB)'),
-          nginx: _('Response metrics (NGINX)'),
-          kubernetes: _('System metrics (Kubernetes)')
-        }
-      end
-    end
-  end
-end
diff --git a/db/importers/common_metrics_importer.rb b/db/importers/common_metrics_importer.rb
index cf5f5e181de..a2e3996a123 100644
--- a/db/importers/common_metrics_importer.rb
+++ b/db/importers/common_metrics_importer.rb
@@ -1,3 +1,9 @@
-# This functionality has been moved to the common_metrics module.
+# This functionality has been moved to the lib/gitlab/importers/common_metrics module.
 # This is here only to preserve existing ::Importers::CommonMetricsImporter api
-require_relative './common_metrics'
+module Importers
+  module CommonMetricsImporter
+    def self.new(*args)
+      Gitlab::Importers::CommonMetrics::Importer.new(*args)
+    end
+  end
+end
diff --git a/lib/gitlab/importers/common_metrics.rb b/lib/gitlab/importers/common_metrics.rb
new file mode 100644
index 00000000000..210ae6cb14a
--- /dev/null
+++ b/lib/gitlab/importers/common_metrics.rb
@@ -0,0 +1,10 @@
+# frozen_string_literal: true
+
+module Gitlab
+  module Importers
+    module CommonMetrics
+    end
+  end
+end
+
+Gitlab::Importers::CommonMetrics.prepend(EE::Gitlab::Importers::CommonMetrics)
diff --git a/lib/gitlab/importers/common_metrics/importer.rb b/lib/gitlab/importers/common_metrics/importer.rb
new file mode 100644
index 00000000000..c916af58820
--- /dev/null
+++ b/lib/gitlab/importers/common_metrics/importer.rb
@@ -0,0 +1,80 @@
+# frozen_string_literal: true
+
+module Gitlab
+  module Importers
+    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
+          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
+
+        # rubocop: disable CodeReuse/ActiveRecord
+        def find_or_build_metric!(id)
+          raise MissingQueryId unless id
+
+          PrometheusMetric.common.find_by(identifier: id) ||
+            PrometheusMetric.new(common: true, identifier: id)
+        end
+        # rubocop: enable CodeReuse/ActiveRecord
+
+        def find_group_title_key(title)
+          PrometheusMetricEnums.groups[find_group_title(title)]
+        end
+
+        def find_group_title(title)
+          PrometheusMetricEnums.group_titles.invert[title]
+        end
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/importers/common_metrics/prometheus_metric.rb b/lib/gitlab/importers/common_metrics/prometheus_metric.rb
new file mode 100644
index 00000000000..a9397f4c055
--- /dev/null
+++ b/lib/gitlab/importers/common_metrics/prometheus_metric.rb
@@ -0,0 +1,12 @@
+# frozen_string_literal: true
+
+module Gitlab
+  module Importers
+    module CommonMetrics
+      class PrometheusMetric < ApplicationRecord
+        enum group: PrometheusMetricEnums.groups
+        scope :common, -> { where(common: true) }
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/importers/common_metrics/prometheus_metric_enums.rb b/lib/gitlab/importers/common_metrics/prometheus_metric_enums.rb
new file mode 100644
index 00000000000..dbf4c9e9b55
--- /dev/null
+++ b/lib/gitlab/importers/common_metrics/prometheus_metric_enums.rb
@@ -0,0 +1,40 @@
+# frozen_string_literal: true
+
+module Gitlab
+  module Importers
+    module CommonMetrics
+      module PrometheusMetricEnums
+        def self.groups
+          {
+            # built-in groups
+            nginx_ingress_vts: -1,
+            ha_proxy: -2,
+            aws_elb: -3,
+            nginx: -4,
+            kubernetes: -5,
+            nginx_ingress: -6,
+
+            # custom groups
+            business: 0,
+            response: 1,
+            system: 2
+          }
+        end
+
+        def self.group_titles
+          {
+            business: _('Business metrics (Custom)'),
+            response: _('Response metrics (Custom)'),
+            system: _('System metrics (Custom)'),
+            nginx_ingress_vts: _('Response metrics (NGINX Ingress VTS)'),
+            nginx_ingress: _('Response metrics (NGINX Ingress)'),
+            ha_proxy: _('Response metrics (HA Proxy)'),
+            aws_elb: _('Response metrics (AWS ELB)'),
+            nginx: _('Response metrics (NGINX)'),
+            kubernetes: _('System metrics (Kubernetes)')
+          }
+        end
+      end
+    end
+  end
+end
diff --git a/spec/db/importers/common_metrics_importer_spec.rb b/spec/db/importers/common_metrics_importer_spec.rb
index c47effa6803..02e7d51c268 100644
--- a/spec/db/importers/common_metrics_importer_spec.rb
+++ b/spec/db/importers/common_metrics_importer_spec.rb
@@ -3,7 +3,7 @@
 require 'rails_helper'
 require Rails.root.join("db", "importers", "common_metrics_importer.rb")
 
-describe Importers::CommonMetrics::PrometheusMetric do
+describe Gitlab::Importers::CommonMetrics::PrometheusMetric do
   let(:existing_group_titles) do
     ::PrometheusMetricEnums.group_details.each_with_object({}) do |(key, value), memo|
       memo[key] = value[:group_title]
@@ -15,7 +15,7 @@ describe Importers::CommonMetrics::PrometheusMetric do
   end
 
   it 'GROUP_TITLES equals ::PrometheusMetric' do
-    expect(Importers::CommonMetrics::PrometheusMetricEnums.group_titles).to eq(existing_group_titles)
+    expect(Gitlab::Importers::CommonMetrics::PrometheusMetricEnums.group_titles).to eq(existing_group_titles)
   end
 end
 
@@ -104,7 +104,7 @@ describe Importers::CommonMetricsImporter do
       let(:query_identifier) { }
 
       it 'raises exception' do
-        expect { subject.execute }.to raise_error(Importers::CommonMetrics::Importer::MissingQueryId)
+        expect { subject.execute }.to raise_error(Gitlab::Importers::CommonMetrics::Importer::MissingQueryId)
       end
     end