Add group enum to custom metrics model + allow querying custom metrics

app/models/prometheus_metric.rb

 class PrometheusMetric < ActiveRecord::Base
   belongs_to :project, required: true, validate: true
+  enum group: [:business, :response, :system]
 
   validates :title, presence: true
   validates :query, presence: true
+
+  def self.to_grouped_query_metrics
+    self.all.group_by(&:group).map do |name, metrics|
+      [name, metrics.map(&:to_query_metric)]
+    end
+  end
+
+  def to_query_metric
+    Gitlab::Prometheus::Metric.new(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

db/migrate/20180104215427_add_group_to_prometheus_metrics.rb

+# See http://doc.gitlab.com/ce/development/migration_style_guide.html
+# for more information on how to write migrations for GitLab.
+
+class AddGroupToPrometheusMetrics < ActiveRecord::Migration
+  include Gitlab::Database::MigrationHelpers
+  DOWNTIME = false
+
+  def change
+    add_column :prometheus_metrics, :group, :integer
+    add_index :prometheus_metrics, :group
+  end
+end

lib/gitlab/prometheus/metric_group.rb

@@ -6,9 +6,19 @@ module Gitlab
       attr_accessor :name, :priority, :metrics
       validates :name, :priority, :metrics, presence: true
 
-      def self.all
+      def self.common_metrics
         AdditionalMetricsParser.load_groups_from_yaml
       end
+
+      def self.for_project(project)
+        common_metrics + custom_metrics(project)
+      end
+
+      def self.custom_metrics(project)
+        project.prometheus_metrics.to_grouped_query_metrics.map do |name, metrics|
+          MetricGroup.new(name: name, priority: 0, metrics: metrics)
+        end
+      end
     end
   end
 end

lib/gitlab/prometheus/queries/additional_metrics_deployment_query.rb

@@ -7,6 +7,7 @@ module Gitlab
         def query(deployment_id)
           Deployment.find_by(id: deployment_id).try do |deployment|
             query_metrics(
+              deployment.project,
               common_query_context(
                 deployment.environment,
                 timeframe_start: (deployment.created_at - 30.minutes).to_f,

lib/gitlab/prometheus/queries/additional_metrics_environment_query.rb

@@ -7,6 +7,7 @@ module Gitlab
         def query(environment_id)
           ::Environment.find_by(id: environment_id).try do |environment|
             query_metrics(
+              environment.project,
               common_query_context(environment, timeframe_start: 8.hours.ago.to_f, timeframe_end: Time.now.to_f)
             )
           end

lib/gitlab/prometheus/queries/matched_metrics_query.rb

@@ -18,7 +18,7 @@ module Gitlab
         private
 
         def groups_data
-          metrics_groups = groups_with_active_metrics(Gitlab::Prometheus::MetricGroup.all)
+          metrics_groups = groups_with_active_metrics(Gitlab::Prometheus::MetricGroup.common_metrics)
           lookup = active_series_lookup(metrics_groups)
 
           groups = {}

lib/gitlab/prometheus/queries/query_additional_metrics.rb

@@ -2,10 +2,10 @@ module Gitlab
   module Prometheus
     module Queries
       module QueryAdditionalMetrics
-        def query_metrics(query_context)
+        def query_metrics(project, query_context)
           query_processor = method(:process_query).curry[query_context]
 
-          groups = matched_metrics.map do |group|
+          groups = matched_metrics(project).map do |group|
             metrics = group.metrics.map do |metric|
               {
                 title: metric.title,
@@ -60,8 +60,8 @@ module Gitlab
           @available_metrics ||= client_label_values || []
         end
 
-        def matched_metrics
-          result = Gitlab::Prometheus::MetricGroup.all.map do |group|
+        def matched_metrics(project)
+          result = Gitlab::Prometheus::MetricGroup.for_project(project).map do |group|
             group.metrics.select! do |metric|
               metric.required_metrics.all?(&available_metrics.method(:include?))
             end

lib/gitlab/prometheus/query.rb

-module Gitlab
-  module Prometheus
-    class Query
-      include ActiveModel::Model
-      # include ActiveRecord::Base
-
-      attr_accessor :unit, :series_dsl, :label, :type, :track
-
-      validates :title, :required_metrics, :weight, :y_label, :queries, presence: true
-
-      def initialize(params = {})
-        super(params)
-      end
-    end
-  end
-end

spec/factories/prometheus_metrics.rb

@@ -4,6 +4,7 @@ FactoryBot.define do
     query 'avg(metric)'
     y_label 'y_label'
     unit 'm/s'
+    group :business
     legend 'legend'
     project nil
   end

spec/lib/gitlab/prometheus/queries/matched_metrics_query_spec.rb

@@ -24,7 +24,7 @@ describe Gitlab::Prometheus::Queries::MatchedMetricsQuery do
 
   context 'with one group where two metrics is found' do
     before do
-      allow(metric_group_class).to receive(:all).and_return([simple_metric_group])
+      allow(metric_group_class).to receive(:common_metrics).and_return([simple_metric_group])
       allow(client).to receive(:label_values).and_return(metric_names)
     end
 
@@ -70,7 +70,7 @@ describe Gitlab::Prometheus::Queries::MatchedMetricsQuery do
 
   context 'with one group where only one metric is found' do
     before do
-      allow(metric_group_class).to receive(:all).and_return([simple_metric_group])
+      allow(metric_group_class).to receive(:common_metrics).and_return([simple_metric_group])
       allow(client).to receive(:label_values).and_return('metric_a')
     end
 
@@ -99,7 +99,7 @@ describe Gitlab::Prometheus::Queries::MatchedMetricsQuery do
     let(:second_metric_group) { simple_metric_group(name: 'nameb', metrics: simple_metrics(added_metric_name: 'metric_c')) }
 
     before do
-      allow(metric_group_class).to receive(:all).and_return([simple_metric_group, second_metric_group])
+      allow(metric_group_class).to receive(:common_metrics).and_return([simple_metric_group, second_metric_group])
       allow(client).to receive(:label_values).and_return('metric_c')
     end
 

spec/support/prometheus/additional_metrics_shared_examples.rb

@@ -12,11 +12,12 @@ RSpec.shared_examples 'additional metrics query' do
 
   let(:client) { double('prometheus_client') }
   let(:query_result) { described_class.new(client).query(*query_params) }
-  let(:environment) { create(:environment, slug: 'environment-slug') }
+  let(:project) { create(:project) }
+  let(:environment) { create(:environment, slug: 'environment-slug', project: project) }
 
   before do
     allow(client).to receive(:label_values).and_return(metric_names)
-    allow(metric_group_class).to receive(:all).and_return([simple_metric_group(metrics: [simple_metric])])
+    allow(metric_group_class).to receive(:common_metrics).and_return([simple_metric_group(metrics: [simple_metric])])
   end
 
   context 'metrics query context' do
@@ -24,13 +25,14 @@ RSpec.shared_examples 'additional metrics query' do
 
     shared_examples 'query context containing environment slug and filter' do
       it 'contains ci_environment_slug' do
-        expect(subject).to receive(:query_metrics).with(hash_including(ci_environment_slug: environment.slug))
+        expect(subject).to receive(:query_metrics).with(project, hash_including(ci_environment_slug: environment.slug))
 
         subject.query(*query_params)
       end
 
       it 'contains environment filter' do
         expect(subject).to receive(:query_metrics).with(
+          project,
           hash_including(
             environment_filter: "container_name!=\"POD\",environment=\"#{environment.slug}\""
           )
@@ -48,7 +50,7 @@ RSpec.shared_examples 'additional metrics query' do
         it_behaves_like 'query context containing environment slug and filter'
 
         it 'query context contains kube_namespace' do
-          expect(subject).to receive(:query_metrics).with(hash_including(kube_namespace: kube_namespace))
+          expect(subject).to receive(:query_metrics).with(project, hash_including(kube_namespace: kube_namespace))
 
           subject.query(*query_params)
         end
@@ -72,7 +74,7 @@ RSpec.shared_examples 'additional metrics query' do
       it_behaves_like 'query context containing environment slug and filter'
 
       it 'query context contains empty kube_namespace' do
-        expect(subject).to receive(:query_metrics).with(hash_including(kube_namespace: ''))
+        expect(subject).to receive(:query_metrics).with(project, hash_including(kube_namespace: ''))
 
         subject.query(*query_params)
       end
@@ -81,7 +83,7 @@ RSpec.shared_examples 'additional metrics query' do
 
   context 'with one group where two metrics is found' do
     before do
-      allow(metric_group_class).to receive(:all).and_return([simple_metric_group])
+      allow(metric_group_class).to receive(:common_metrics).and_return([simple_metric_group])
     end
 
     context 'some queries return results' do
@@ -113,11 +115,55 @@ RSpec.shared_examples 'additional metrics query' do
     end
   end
 
+  context 'with custom metrics' do
+    let!(:metric) { create(:prometheus_metric, project: project) }
+    before do
+      allow(client).to receive(:query_range).with('avg(metric)', any_args).and_return(query_range_result)
+    end
+
+    context 'without common metrics' do
+      before do
+        allow(metric_group_class).to receive(:common_metrics).and_return([])
+      end
+
+      it 'return group data for custom metric' do
+        queries_with_result = { queries: [{ query_range: 'avg(metric)', unit: 'm/s', label: 'legend', result: query_range_result }] }
+        expect(query_result).to match_schema('prometheus/additional_metrics_query_result')
+
+        expect(query_result.count).to eq(1)
+        expect(query_result.first[:metrics].count).to eq(1)
+
+        expect(query_result.first[:metrics].first).to include(queries_with_result)
+      end
+    end
+
+    context 'with common metrics' do
+      before do
+        allow(client).to receive(:query_range).with('query_range_a', any_args).and_return(query_range_result)
+
+        allow(metric_group_class).to receive(:common_metrics).and_return([simple_metric_group(metrics: [simple_metric])])
+      end
+
+      it 'return group data for custom metric' do
+        custom_queries_with_result = { queries: [{ query_range: 'avg(metric)', unit: 'm/s', label: 'legend', result: query_range_result }] }
+        common_queries_with_result = { queries: [{ query_range: 'query_range_a', result: query_range_result }] }
+
+        expect(query_result).to match_schema('prometheus/additional_metrics_query_result')
+
+        expect(query_result.count).to eq(2)
+        expect(query_result).to all(satisfy { |r| r[:metrics].count == 1 })
+
+        expect(query_result[0][:metrics].first).to include(common_queries_with_result)
+        expect(query_result[1][:metrics].first).to include(custom_queries_with_result)
+      end
+    end
+  end
+
   context 'with two groups with one metric each' do
     let(:metrics) { [simple_metric(queries: [simple_query])] }
 
     before do
-      allow(metric_group_class).to receive(:all).and_return(
+      allow(metric_group_class).to receive(:common_metrics).and_return(
         [
           simple_metric_group(name: 'group_a', metrics: [simple_metric(queries: [simple_query])]),
           simple_metric_group(name: 'group_b', metrics: [simple_metric(title: 'title_b', queries: [simple_query('b')])])