Merge branch '28717-additional-metrics-review-branch' into 'master'

Support additional prometheus metrics - review branch

Closes #28717

See merge request !11712

app/assets/javascripts/prometheus_metrics/constants.js

+export default {
+  EMPTY: 'empty',
+  LOADING: 'loading',
+  LIST: 'list',
+};

app/assets/javascripts/prometheus_metrics/index.js

+import PrometheusMetrics from './prometheus_metrics';
+
+$(() => {
+  const prometheusMetrics = new PrometheusMetrics('.js-prometheus-metrics-monitoring');
+  prometheusMetrics.loadActiveMetrics();
+});

app/assets/javascripts/prometheus_metrics/prometheus_metrics.js

+import PANEL_STATE from './constants';
+
+export default class PrometheusMetrics {
+  constructor(wrapperSelector) {
+    this.backOffRequestCounter = 0;
+
+    this.$wrapper = $(wrapperSelector);
+
+    this.$monitoredMetricsPanel = this.$wrapper.find('.js-panel-monitored-metrics');
+    this.$monitoredMetricsCount = this.$monitoredMetricsPanel.find('.js-monitored-count');
+    this.$monitoredMetricsLoading = this.$monitoredMetricsPanel.find('.js-loading-metrics');
+    this.$monitoredMetricsEmpty = this.$monitoredMetricsPanel.find('.js-empty-metrics');
+    this.$monitoredMetricsList = this.$monitoredMetricsPanel.find('.js-metrics-list');
+
+    this.$missingEnvVarPanel = this.$wrapper.find('.js-panel-missing-env-vars');
+    this.$panelToggle = this.$missingEnvVarPanel.find('.js-panel-toggle');
+    this.$missingEnvVarMetricCount = this.$missingEnvVarPanel.find('.js-env-var-count');
+    this.$missingEnvVarMetricsList = this.$missingEnvVarPanel.find('.js-missing-var-metrics-list');
+
+    this.activeMetricsEndpoint = this.$monitoredMetricsPanel.data('active-metrics');
+
+    this.$panelToggle.on('click', e => this.handlePanelToggle(e));
+  }
+
+  /* eslint-disable class-methods-use-this */
+  handlePanelToggle(e) {
+    const $toggleBtn = $(e.currentTarget);
+    const $currentPanelBody = $toggleBtn.closest('.panel').find('.panel-body');
+    $currentPanelBody.toggleClass('hidden');
+    if ($toggleBtn.hasClass('fa-caret-down')) {
+      $toggleBtn.removeClass('fa-caret-down').addClass('fa-caret-right');
+    } else {
+      $toggleBtn.removeClass('fa-caret-right').addClass('fa-caret-down');
+    }
+  }
+
+  showMonitoringMetricsPanelState(stateName) {
+    switch (stateName) {
+      case PANEL_STATE.LOADING:
+        this.$monitoredMetricsLoading.removeClass('hidden');
+        this.$monitoredMetricsEmpty.addClass('hidden');
+        this.$monitoredMetricsList.addClass('hidden');
+        break;
+      case PANEL_STATE.LIST:
+        this.$monitoredMetricsLoading.addClass('hidden');
+        this.$monitoredMetricsEmpty.addClass('hidden');
+        this.$monitoredMetricsList.removeClass('hidden');
+        break;
+      default:
+        this.$monitoredMetricsLoading.addClass('hidden');
+        this.$monitoredMetricsEmpty.removeClass('hidden');
+        this.$monitoredMetricsList.addClass('hidden');
+        break;
+    }
+  }
+
+  populateActiveMetrics(metrics) {
+    let totalMonitoredMetrics = 0;
+    let totalMissingEnvVarMetrics = 0;
+
+    metrics.forEach((metric) => {
+      this.$monitoredMetricsList.append(`<li>${metric.group}<span class="badge">${metric.active_metrics}</span></li>`);
+      totalMonitoredMetrics += metric.active_metrics;
+      if (metric.metrics_missing_requirements > 0) {
+        this.$missingEnvVarMetricsList.append(`<li>${metric.group}</li>`);
+        totalMissingEnvVarMetrics += 1;
+      }
+    });
+
+    this.$monitoredMetricsCount.text(totalMonitoredMetrics);
+    this.showMonitoringMetricsPanelState(PANEL_STATE.LIST);
+
+    if (totalMissingEnvVarMetrics > 0) {
+      this.$missingEnvVarPanel.removeClass('hidden');
+      this.$missingEnvVarPanel.find('.flash-container').off('click');
+      this.$missingEnvVarMetricCount.text(totalMissingEnvVarMetrics);
+    }
+  }
+
+  loadActiveMetrics() {
+    this.showMonitoringMetricsPanelState(PANEL_STATE.LOADING);
+    gl.utils.backOff((next, stop) => {
+      $.getJSON(this.activeMetricsEndpoint)
+        .done((res) => {
+          if (res && res.success) {
+            stop(res);
+          } else {
+            this.backOffRequestCounter = this.backOffRequestCounter += 1;
+            if (this.backOffRequestCounter < 3) {
+              next();
+            } else {
+              stop(res);
+            }
+          }
+        })
+        .fail(stop);
+    })
+    .then((res) => {
+      if (res && res.data && res.data.length) {
+        this.populateActiveMetrics(res.data);
+      } else {
+        this.showMonitoringMetricsPanelState(PANEL_STATE.EMPTY);
+      }
+    })
+    .catch(() => {
+      this.showMonitoringMetricsPanelState(PANEL_STATE.EMPTY);
+    });
+  }
+}

app/assets/stylesheets/pages/settings.scss

@@ -126,3 +126,66 @@
     margin-left: 5px;
   }
 }
+
+.prometheus-metrics-monitoring {
+  .panel {
+    .panel-toggle {
+      width: 14px;
+    }
+
+    .badge {
+      font-size: inherit;
+    }
+
+    .panel-heading .badge-count {
+      color: $white-light;
+      background: $common-gray-dark;
+    }
+
+    .panel-body {
+      padding: 0;
+    }
+
+    .flash-container {
+      margin-bottom: 0;
+      cursor: default;
+
+      .flash-notice {
+        border-radius: 0;
+      }
+    }
+  }
+
+  .loading-metrics,
+  .empty-metrics {
+    padding: 30px 10px;
+
+    p,
+    .btn {
+      margin-top: 10px;
+      margin-bottom: 0;
+    }
+  }
+
+  .loading-metrics .metrics-load-spinner {
+    color: $loading-color;
+  }
+
+  .metrics-list {
+    margin-bottom: 0;
+
+    li {
+      padding: $gl-padding;
+
+      .badge {
+        margin-left: 5px;
+        background: $badge-bg;
+      }
+    }
+
+    /* Ensure we don't add border if there's only single li */
+    li + li {
+      border-top: 1px solid $border-color;
+    }
+  }
+}

app/controllers/application_controller.rb

@@ -40,6 +40,10 @@ class ApplicationController < ActionController::Base
     render_404
   end
+  rescue_from(ActionController::UnknownFormat) do
+    render_404
+  end
+
   rescue_from Gitlab::Access::AccessDeniedError do |exception|
     render_403
   end

app/controllers/projects/deployments_controller.rb

@@ -22,6 +22,22 @@ class Projects::DeploymentsController < Projects::ApplicationController
     render_404
   end
+  def additional_metrics
+    return render_404 unless deployment.has_additional_metrics?
+
+    respond_to do |format|
+      format.json do
+        metrics = deployment.additional_metrics
+
+        if metrics.any?
+          render json: metrics
+        else
+          head :no_content
+        end
+      end
+    end
+  end
+
   private
   def deployment

app/controllers/projects/environments_controller.rb

@@ -129,6 +129,16 @@ class Projects::EnvironmentsController < Projects::ApplicationController
     end
   end
+  def additional_metrics
+    respond_to do |format|
+      format.json do
+        additional_metrics = environment.additional_metrics || {}
+
+        render json: additional_metrics, status: additional_metrics.any? ? :ok : :no_content
+      end
+    end
+  end
+
   private
   def verify_api_request!

app/controllers/projects/prometheus_controller.rb

+class Projects::PrometheusController < Projects::ApplicationController
+  before_action :authorize_read_project!
+  before_action :require_prometheus_metrics!
+
+  def active_metrics
+    respond_to do |format|
+      format.json do
+        matched_metrics = project.prometheus_service.matched_metrics || {}
+
+        if matched_metrics.any?
+          render json: matched_metrics
+        else
+          head :no_content
+        end
+      end
+    end
+  end
+
+  private
+
+  def require_prometheus_metrics!
+    render_404 unless project.prometheus_service.present?
+  end
+end

app/models/deployment.rb

@@ -114,6 +114,17 @@ class Deployment < ActiveRecord::Base
     project.monitoring_service.deployment_metrics(self)
   end
+  def has_additional_metrics?
+    project.prometheus_service.present?
+  end
+
+  def additional_metrics
+    return {} unless project.prometheus_service.present?
+
+    metrics = project.prometheus_service.additional_deployment_metrics(self)
+    metrics&.merge(deployment_time: created_at.to_i) || {}
+  end
+
   private
   def ref_path

app/models/environment.rb

@@ -157,6 +157,16 @@ class Environment < ActiveRecord::Base
     project.monitoring_service.environment_metrics(self) if has_metrics?
   end
+  def has_additional_metrics?
+    project.prometheus_service.present? && available? && last_deployment.present?
+  end
+
+  def additional_metrics
+    if has_additional_metrics?
+      project.prometheus_service.additional_environment_metrics(self)
+    end
+  end
+
   # An environment name is not necessarily suitable for use in URLs, DNS
   # or other third-party contexts, so provide a slugified version. A slug has
   # the following properties:

app/models/project_services/prometheus_service.rb

@@ -28,17 +28,6 @@ class PrometheusService < MonitoringService
     'Prometheus monitoring'
   end
-  def help
-    <<-MD.strip_heredoc
-      Retrieves the Kubernetes node metrics `container_cpu_usage_seconds_total`
-      and `container_memory_usage_bytes` from the configured Prometheus server.
-
-      If you are not using [Auto-Deploy](https://docs.gitlab.com/ee/ci/autodeploy/index.html)
-      or have set up your own Prometheus server, an `environment` label is required on each metric to
-      [identify the Environment](https://docs.gitlab.com/ce/user/project/integrations/prometheus.html#metrics-and-labels).
-    MD
-  end
-
   def self.to_param
     'prometheus'
   end
@@ -50,6 +39,7 @@ class PrometheusService < MonitoringService
         name: 'api_url',
         title: 'API URL',
         placeholder: 'Prometheus API Base URL, like http://prometheus.example.com/',
+        help: 'By default, Prometheus listens on ‘http://localhost:9090’. It’s not recommended to change the default address and port as this might affect or conflict with other services running on the GitLab server.',
         required: true
       }
     ]
@@ -65,23 +55,34 @@ class PrometheusService < MonitoringService
   end
   def environment_metrics(environment)
-    with_reactive_cache(Gitlab::Prometheus::Queries::EnvironmentQuery.name, environment.id, &:itself)
+    with_reactive_cache(Gitlab::Prometheus::Queries::EnvironmentQuery.name, environment.id, &method(:rename_data_to_metrics))
   end
   def deployment_metrics(deployment)
-    metrics = with_reactive_cache(Gitlab::Prometheus::Queries::DeploymentQuery.name, deployment.id, &:itself)
+    metrics = with_reactive_cache(Gitlab::Prometheus::Queries::DeploymentQuery.name, deployment.id, &method(:rename_data_to_metrics))
     metrics&.merge(deployment_time: created_at.to_i) || {}
   end
+  def additional_environment_metrics(environment)
+    with_reactive_cache(Gitlab::Prometheus::Queries::AdditionalMetricsEnvironmentQuery.name, environment.id, &:itself)
+  end
+
+  def additional_deployment_metrics(deployment)
+    with_reactive_cache(Gitlab::Prometheus::Queries::AdditionalMetricsDeploymentQuery.name, deployment.id, &:itself)
+  end
+
+  def matched_metrics
+    with_reactive_cache(Gitlab::Prometheus::Queries::MatchedMetricsQuery.name, &:itself)
+  end
+
   # Cache metrics for specific environment
   def calculate_reactive_cache(query_class_name, *args)
     return unless active? && project && !project.pending_delete?
-    metrics = Kernel.const_get(query_class_name).new(client).query(*args)
-
+    data = Kernel.const_get(query_class_name).new(client).query(*args)
     {
       success: true,
-      metrics: metrics,
+      data: data,
       last_update: Time.now.utc
     }
   rescue Gitlab::PrometheusError => err
@@ -91,4 +92,11 @@ class PrometheusService < MonitoringService
   def client
     @prometheus ||= Gitlab::PrometheusClient.new(api_url: api_url)
   end
+
+  private
+
+  def rename_data_to_metrics(metrics)
+    metrics[:metrics] = metrics.delete :data
+    metrics
+  end
 end

app/views/projects/services/_form.html.haml

@@ -23,3 +23,7 @@
             - disabled_title = @service.disabled_title
         = link_to 'Cancel', namespace_project_settings_integrations_path(@project.namespace, @project), class: 'btn btn-cancel'
+
+- if lookup_context.template_exists?('show', "projects/services/#{@service.to_param}", true)
+  %hr
+  = render "projects/services/#{@service.to_param}/show"

app/views/projects/services/prometheus/_show.html.haml

+- content_for :page_specific_javascripts do
+  = webpack_bundle_tag('prometheus_metrics')
+
+.row.prepend-top-default.append-bottom-default.prometheus-metrics-monitoring.js-prometheus-metrics-monitoring
+  .col-lg-3
+    %h4.prepend-top-0
+      Metrics
+    %p
+      Metrics are automatically configured and monitored
+      based on a library of metrics from popular exporters.
+      = link_to 'More information', '#'
+
+  .col-lg-9
+    .panel.panel-default.js-panel-monitored-metrics{ data: { "active-metrics" => "#{namespace_project_prometheus_active_metrics_path(@project.namespace, @project, :json)}" } }
+      .panel-heading
+        %h3.panel-title
+          Monitored
+          %span.badge.js-monitored-count 0
+      .panel-body
+        .loading-metrics.text-center.js-loading-metrics
+          = icon('spinner spin 3x', class: 'metrics-load-spinner')
+          %p Finding and configuring metrics...
+        .empty-metrics.text-center.hidden.js-empty-metrics
+          = custom_icon('icon_empty_metrics')
+          %p No metrics are being monitored. To start monitoring, deploy to an environment.
+          = link_to project_environments_path(@project), title: 'View environments', class: 'btn btn-success' do
+            View environments
+        %ul.list-unstyled.metrics-list.hidden.js-metrics-list
+
+    .panel.panel-default.hidden.js-panel-missing-env-vars
+      .panel-heading
+        %h3.panel-title
+          = icon('caret-right lg fw', class: 'panel-toggle js-panel-toggle', 'aria-label' => 'Toggle panel')
+          Missing environment variable
+          %span.badge.js-env-var-count 0
+      .panel-body.hidden
+        .flash-container
+          .flash-notice
+            .flash-text
+              To set up automatic monitoring, add the environment variable
+              %code
+                $CI_ENVIRONMENT_SLUG
+              to exporter’s queries.
+              = link_to 'More information', '#'
+        %ul.list-unstyled.metrics-list.js-missing-var-metrics-list

app/views/shared/icons/_icon_empty_metrics.svg

+<svg xmlns="http://www.w3.org/2000/svg" width="64" height="64" viewBox="0 0 64 64">
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+  </g>
+</svg>

changelogs/unreleased/28717-support-additional-prometheus-metrics.yml

+---
+title: Additional Prometheus metrics support
+merge_request: 11712
+author:

config/prometheus/additional_metrics.yml

+- group: Kubernetes
+  priority: 1
+  metrics:
+  - title: "Memory usage"
+    y_label: "Values"
+    required_metrics:
+      - container_memory_usage_bytes
+    weight: 1
+    queries:
+    - query_range: 'avg(container_memory_usage_bytes{%{environment_filter}}) / 2^20'
+      label: Container memory
+      unit: MiB
+  - title: "Current memory usage"
+    required_metrics:
+     - container_memory_usage_bytes
+    weight: 1
+    queries:
+    - query: 'avg(container_memory_usage_bytes{%{environment_filter}}) / 2^20'
+      display_empty: false
+      unit: MiB
+  - title: "CPU usage"
+    required_metrics:
+     - container_cpu_usage_seconds_total
+    weight: 1
+    queries:
+    - query_range: 'avg(rate(container_cpu_usage_seconds_total{%{environment_filter}}[2m])) * 100'
+  - title: "Current CPU usage"
+    required_metrics:
+     - container_cpu_usage_seconds_total
+    weight: 1
+    queries:
+    - query: 'avg(rate(container_cpu_usage_seconds_total{%{environment_filter}}[2m])) * 100'

config/routes/project.rb

@@ -73,6 +73,10 @@ constraints(ProjectUrlConstrainer.new) do
       resource :mattermost, only: [:new, :create]
+      namespace :prometheus do
+        get :active_metrics
+      end
+
       resources :deploy_keys, constraints: { id: /\d+/ }, only: [:index, :new, :create, :edit, :update] do
         member do
           put :enable
@@ -153,6 +157,7 @@ constraints(ProjectUrlConstrainer.new) do
           post :stop
           get :terminal
           get :metrics
+          get :additional_metrics
           get '/terminal.ws/authorize', to: 'environments#terminal_websocket_authorize', constraints: { format: nil }
         end
@@ -163,6 +168,7 @@ constraints(ProjectUrlConstrainer.new) do
         resources :deployments, only: [:index] do
           member do
             get :metrics
+            get :additional_metrics
           end
         end
       end

config/webpack.config.js

@@ -55,6 +55,7 @@ var config = {
     pipelines:            './pipelines/pipelines_bundle.js',
     pipelines_details:     './pipelines/pipeline_details_bundle.js',
     profile:              './profile/profile_bundle.js',
+    prometheus_metrics:   './prometheus_metrics',
     protected_branches:   './protected_branches/protected_branches_bundle.js',
     protected_tags:       './protected_tags',
     sidebar:              './sidebar/sidebar_bundle.js',

lib/gitlab/prometheus/additional_metrics_parser.rb

+module Gitlab
+  module Prometheus
+    module AdditionalMetricsParser
+      extend self
+
+      def load_groups_from_yaml
+        additional_metrics_raw.map(&method(:group_from_entry))
+      end
+
+      private
+
+      def validate!(obj)
+        raise ParsingError.new(obj.errors.full_messages.join('\n')) unless obj.valid?
+      end
+
+      def group_from_entry(entry)
+        entry[:name] = entry.delete(:group)
+        entry[:metrics]&.map! do |entry|
+          Metric.new(entry).tap(&method(:validate!))
+        end
+
+        MetricGroup.new(entry).tap(&method(:validate!))
+      end
+
+      def additional_metrics_raw
+        load_yaml_file&.map(&:deep_symbolize_keys).freeze
+      end
+
+      def load_yaml_file
+        @loaded_yaml_file ||= YAML.load_file(Rails.root.join('config/prometheus/additional_metrics.yml'))
+      end
+    end
+  end
+end

lib/gitlab/prometheus/metric.rb

+module Gitlab
+  module Prometheus
+    class Metric
+      include ActiveModel::Model
+
+      attr_accessor :title, :required_metrics, :weight, :y_label, :queries
+
+      validates :title, :required_metrics, :weight, :y_label, :queries, presence: true
+
+      def initialize(params = {})
+        super(params)
+        @y_label ||= 'Values'
+      end
+    end
+  end
+end