Extend prometheus metrics for EE

ee/app/controllers/projects/prometheus/alerts_controller.rb

@@ -82,7 +82,7 @@ module Projects
       end
 
       def alert
-        @alert ||= project.prometheus_alerts.find_by(prometheus_metric: params[:id]) || render_404
+        @alert ||= project.prometheus_alerts.find_by(prometheus_metric_id: params[:id]) || render_404
       end
 
       def application

ee/app/models/ee/prometheus_metric.rb

+module EE
+  module PrometheusMetric
+    extend ActiveSupport::Concern
+    extend ::Gitlab::Utils::Override
+
+    prepended do
+      has_many :prometheus_alerts, inverse_of: :prometheus_metric
+    end
+  end
+end

ee/app/models/prometheus_alert.rb

@@ -7,11 +7,14 @@ class PrometheusAlert < ActiveRecord::Base
 
   belongs_to :environment, required: true, validate: true, inverse_of: :prometheus_alerts
   belongs_to :project, required: true, validate: true, inverse_of: :prometheus_alerts
-  belongs_to :prometheus_metric, required: true, validate: true, inverse_of: :prometheus_alert
+  belongs_to :prometheus_metric, required: true, validate: true, inverse_of: :prometheus_alerts
 
   after_save :clear_prometheus_adapter_cache!
   after_destroy :clear_prometheus_adapter_cache!
 
+  validate :require_valid_environment_project!
+  validate :require_valid_metric_project!
+
   enum operator: [:lt, :eq, :gt]
 
   delegate :title, :query, to: :prometheus_metric
@@ -45,4 +48,17 @@ class PrometheusAlert < ActiveRecord::Base
   def clear_prometheus_adapter_cache!
     environment.clear_prometheus_reactive_cache!(:additional_metrics_environment)
   end
+
+  def require_valid_environment_project!
+    return if project == environment.project
+
+    errors.add(:environment, "invalid project")
+  end
+
+  def require_valid_metric_project!
+    return if prometheus_metric.default?
+    return if project == prometheus_metric.project
+
+    errors.add(:prometheus_metric, "invalid project")
+  end
 end

ee/app/models/prometheus_metric.rb

-class PrometheusMetric < ActiveRecord::Base
-  belongs_to :project, required: true, validate: true, inverse_of: :prometheus_metrics
-
-  has_one :prometheus_alert, inverse_of: :prometheus_metric
-
-  enum group: [:business, :response, :system]
-
-  validates :title, presence: true
-  validates :query, presence: true
-  validates :group, presence: true
-  validates :y_label, presence: true
-  validates :unit, presence: true
-
-  GROUP_TITLES = {
-    business: _('Business metrics (Custom)'),
-    response: _('Response metrics (Custom)'),
-    system: _('System metrics (Custom)')
-  }.freeze
-
-  def group_title
-    GROUP_TITLES[group.to_sym]
-  end
-
-  def to_query_metric
-    Gitlab::Prometheus::Metric.new(id: id, title: title, required_metrics: [], weight: 0, y_label: y_label, queries: build_queries)
-  end
-
-  private
-
-  def build_queries
-    [
-      {
-        query_range: query,
-        unit: unit,
-        label: legend
-      }
-    ]
-  end
-end

ee/app/services/projects/prometheus/metrics/base_service.rb

@@ -2,6 +2,8 @@ module Projects
   module Prometheus
     module Metrics
       class BaseService
+        include StrongMemoize
+
         def initialize(metric, params = {})
           @metric = metric
           @project = metric.project
@@ -13,15 +15,25 @@ module Projects
         attr_reader :metric, :project, :params
 
         def application
-          metric.prometheus_alert.environment.cluster_prometheus_adapter
+          alert.environment.cluster_prometheus_adapter
         end
 
         def schedule_alert_update
-          ::Clusters::Applications::ScheduleUpdateService.new(application, project).execute
+          return unless alert
+          return unless alert.environment
+
+          ::Clusters::Applications::ScheduleUpdateService.new(
+            alert.environment.cluster_prometheus_adapter, project).execute
+        end
+
+        def alert
+          strong_memoize(:alert) do
+            metric.prometheus_alerts.find_by(project: project)
+          end
         end
 
         def has_alert?
-          metric.prometheus_alert.present?
+          alert.present?
         end
       end
     end

ee/db/migrate/20180101160629_create_prometheus_metrics.rb

-class CreatePrometheusMetrics < ActiveRecord::Migration
-  DOWNTIME = false
-
-  def change
-    create_table :prometheus_metrics do |t|
-      t.references :project, index: true, foreign_key: { on_delete: :cascade }, null: false
-      t.string :title, null: false
-      t.string :query, null: false
-      t.string :y_label
-      t.string :unit
-      t.string :legend
-      t.integer :group, null: false, index: true
-      t.timestamps_with_timezone null: false
-    end
-  end
-end

ee/db/migrate/20180831134049_allow_many_prometheus_alerts.rb

+class AllowManyPrometheusAlerts < ActiveRecord::Migration
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  disable_ddl_transaction!
+
+  def up
+    add_concurrent_index :prometheus_alerts, [:project_id, :prometheus_metric_id], unique: true
+    remove_concurrent_index :prometheus_alerts, :prometheus_metric_id, unique: true
+  end
+
+  def down
+    add_concurrent_index :prometheus_alerts, :prometheus_metric_id, unique: true
+    remove_concurrent_index :prometheus_alerts, [:project_id, :prometheus_metric_id], unique: true
+  end
+end

ee/lib/gitlab/prometheus/metric_group.rb

+module EE
+  module Gitlab
+    module Prometheus
+      module MetricGroup
+        extend ActiveSupport::Concern
+        extend ::Gitlab::Utils::Override
+
+        prepended do
+          def self.custom_metrics(project)
+            project.prometheus_metrics.all.group_by(&:group_title).map do |name, metrics|
+              MetricGroup.new(name: name, priority: 0, metrics: metrics.map(&:to_query_metric))
+            end
+          end
+
+          override :for_project
+          def self.for_project(project)
+            super + custom_metrics(project)
+          end
+        end
+      end
+    end
+  end
+end

ee/spec/factories/prometheus_metrics.rb

-FactoryBot.define do
-  factory :prometheus_metric, class: PrometheusMetric do
-    title 'title'
-    query 'avg(metric)'
-    y_label 'y_label'
-    unit 'm/s'
-    group :business
-    project
-    legend 'legend'
-  end
-end

ee/spec/models/prometheus_metric_spec.rb

-require 'spec_helper'
-
-describe PrometheusMetric do
-  subject { build(:prometheus_metric) }
-
-  it { is_expected.to belong_to(:project) }
-  it { is_expected.to validate_presence_of(:title) }
-  it { is_expected.to validate_presence_of(:query) }
-  it { is_expected.to validate_presence_of(:group) }
-
-  describe '#group_title' do
-    shared_examples 'group_title' do |group, title|
-      subject { build(:prometheus_metric, group: group).group_title }
-
-      it "returns text #{title} for group #{group}" do
-        expect(subject).to eq(title)
-      end
-    end
-
-    it_behaves_like 'group_title', :business, 'Business metrics (Custom)'
-    it_behaves_like 'group_title', :response, 'Response metrics (Custom)'
-    it_behaves_like 'group_title', :system, 'System metrics (Custom)'
-  end
-
-  describe '#to_query_metric' do
-    it 'converts to queryable metric object' do
-      expect(subject.to_query_metric).to be_instance_of(Gitlab::Prometheus::Metric)
-    end
-
-    it 'queryable metric object has title' do
-      expect(subject.to_query_metric.title).to eq(subject.title)
-    end
-
-    it 'queryable metric object has y_label' do
-      expect(subject.to_query_metric.y_label).to eq(subject.y_label)
-    end
-
-    it 'queryable metric has no required_metric' do
-      expect(subject.to_query_metric.required_metrics).to eq([])
-    end
-
-    it 'queryable metric has weight 0' do
-      expect(subject.to_query_metric.weight).to eq(0)
-    end
-
-    it 'queryable metrics has query description' do
-      queries = [
-        {
-          query_range: subject.query,
-          unit: subject.unit,
-          label: subject.legend
-        }
-      ]
-
-      expect(subject.to_query_metric.queries).to eq(queries)
-    end
-  end
-end

lib/gitlab/prometheus/metric_group.rb

 module Gitlab
   module Prometheus
     class MetricGroup
+      prepend EE::Gitlab::Prometheus::MetricGroup
       include ActiveModel::Model
 
       attr_accessor :name, :priority, :metrics
@@ -13,14 +14,9 @@ module Gitlab
         end
       end
 
-      def self.for_project(project)
-        common_metrics + custom_metrics(project)
-      end
-
-      def self.custom_metrics(project)
-        project.prometheus_metrics.all.group_by(&:group_title).map do |name, metrics|
-          MetricGroup.new(name: name, priority: 0, metrics: metrics.map(&:to_query_metric))
-        end
+      # EE only
+      def self.for_project(_)
+        common_metrics
       end
     end
   end