Merge branch '28717-fe-prometheus-additional-metrics' into '28717-additional-metrics-review-branch'

Support additional Prometheus metrics in Prometheus Integration

See merge request !11794

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

@@ -35,3 +35,66 @@
     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/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
@@ -49,7 +38,8 @@ class PrometheusService < MonitoringService
         type: 'text',
         name: 'api_url',
         title: 'API URL',
-        placeholder: 'Prometheus API Base URL, like http://prometheus.example.com/'
+        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.'
       }
     ]
   end

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

@@ -18,3 +18,7 @@
 
           = link_to 'Test settings', test_namespace_project_service_path(@project.namespace, @project, @service), class: "btn #{disabled_class}", title: 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">
+  <g fill="#E5E5E5">
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+  </g>
+</svg>

config/webpack.config.js

@@ -51,6 +51,7 @@ var config = {
     pipelines:            './pipelines/index.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',

spec/factories/services.rb

@@ -25,6 +25,14 @@ FactoryGirl.define do
     })
   end
 
+  factory :prometheus_service do
+    project factory: :empty_project
+    active true
+    properties({
+      api_url: 'https://prometheus.example.com/'
+    })
+  end
+
   factory :jira_service do
     project factory: :empty_project
     active true

spec/javascripts/fixtures/prometheus_service.rb

+require 'spec_helper'
+
+describe Projects::ServicesController, '(JavaScript fixtures)', type: :controller do
+  include JavaScriptFixturesHelpers
+
+  let(:admin)     { create(:admin) }
+  let(:namespace) { create(:namespace, name: 'frontend-fixtures' )}
+  let(:project)   { create(:project_empty_repo, namespace: namespace, path: 'services-project') }
+  let!(:service)  { create(:prometheus_service, project: project) }
+  
+
+  render_views
+
+  before(:all) do
+    clean_frontend_fixtures('services/')
+  end
+
+  before(:each) do
+    sign_in(admin)
+  end
+
+  it 'services/prometheus_service.html.raw' do |example|
+    get :edit,
+      namespace_id: namespace,
+      project_id: project,
+      id: service.to_param
+
+    expect(response).to be_success
+    store_frontend_fixture(response, example.description)
+  end
+end

spec/javascripts/prometheus_metrics/mock_data.js

+export const metrics = [
+  {
+    group: 'Kubernetes',
+    priority: 1,
+    active_metrics: 4,
+    metrics_missing_requirements: 0,
+  },
+  {
+    group: 'HAProxy',
+    priority: 2,
+    active_metrics: 3,
+    metrics_missing_requirements: 0,
+  },
+  {
+    group: 'Apache',
+    priority: 3,
+    active_metrics: 5,
+    metrics_missing_requirements: 0,
+  },
+];
+
+export const missingVarMetrics = [
+  {
+    group: 'Kubernetes',
+    priority: 1,
+    active_metrics: 4,
+    metrics_missing_requirements: 0,
+  },
+  {
+    group: 'HAProxy',
+    priority: 2,
+    active_metrics: 3,
+    metrics_missing_requirements: 1,
+  },
+  {
+    group: 'Apache',
+    priority: 3,
+    active_metrics: 5,
+    metrics_missing_requirements: 3,
+  },
+];

spec/javascripts/prometheus_metrics/prometheus_metrics_spec.js

+import PrometheusMetrics from '~/prometheus_metrics/prometheus_metrics';
+import PANEL_STATE from '~/prometheus_metrics/constants';
+import { metrics, missingVarMetrics } from './mock_data';
+
+describe('PrometheusMetrics', () => {
+  const FIXTURE = 'services/prometheus_service.html.raw';
+  preloadFixtures(FIXTURE);
+
+  beforeEach(() => {
+    loadFixtures(FIXTURE);
+  });
+
+  describe('constructor', () => {
+    let prometheusMetrics;
+
+    beforeEach(() => {
+      prometheusMetrics = new PrometheusMetrics('.js-prometheus-metrics-monitoring');
+    });
+
+    it('should initialize wrapper element refs on class object', () => {
+      expect(prometheusMetrics.$wrapper).toBeDefined();
+      expect(prometheusMetrics.$monitoredMetricsPanel).toBeDefined();
+      expect(prometheusMetrics.$monitoredMetricsCount).toBeDefined();
+      expect(prometheusMetrics.$monitoredMetricsLoading).toBeDefined();
+      expect(prometheusMetrics.$monitoredMetricsEmpty).toBeDefined();
+      expect(prometheusMetrics.$monitoredMetricsList).toBeDefined();
+      expect(prometheusMetrics.$missingEnvVarPanel).toBeDefined();
+      expect(prometheusMetrics.$panelToggle).toBeDefined();
+      expect(prometheusMetrics.$missingEnvVarMetricCount).toBeDefined();
+      expect(prometheusMetrics.$missingEnvVarMetricsList).toBeDefined();
+    });
+
+    it('should initialize metadata on class object', () => {
+      expect(prometheusMetrics.backOffRequestCounter).toEqual(0);
+      expect(prometheusMetrics.activeMetricsEndpoint).toContain('/test');
+    });
+  });
+
+  describe('showMonitoringMetricsPanelState', () => {
+    let prometheusMetrics;
+
+    beforeEach(() => {
+      prometheusMetrics = new PrometheusMetrics('.js-prometheus-metrics-monitoring');
+    });
+
+    it('should show loading state when called with `loading`', () => {
+      prometheusMetrics.showMonitoringMetricsPanelState(PANEL_STATE.LOADING);
+
+      expect(prometheusMetrics.$monitoredMetricsLoading.hasClass('hidden')).toBeFalsy();
+      expect(prometheusMetrics.$monitoredMetricsEmpty.hasClass('hidden')).toBeTruthy();
+      expect(prometheusMetrics.$monitoredMetricsList.hasClass('hidden')).toBeTruthy();
+    });
+
+    it('should show metrics list when called with `list`', () => {
+      prometheusMetrics.showMonitoringMetricsPanelState(PANEL_STATE.LIST);
+
+      expect(prometheusMetrics.$monitoredMetricsLoading.hasClass('hidden')).toBeTruthy();
+      expect(prometheusMetrics.$monitoredMetricsEmpty.hasClass('hidden')).toBeTruthy();
+      expect(prometheusMetrics.$monitoredMetricsList.hasClass('hidden')).toBeFalsy();
+    });
+
+    it('should show empty state when called with `empty`', () => {
+      prometheusMetrics.showMonitoringMetricsPanelState(PANEL_STATE.EMPTY);
+
+      expect(prometheusMetrics.$monitoredMetricsLoading.hasClass('hidden')).toBeTruthy();
+      expect(prometheusMetrics.$monitoredMetricsEmpty.hasClass('hidden')).toBeFalsy();
+      expect(prometheusMetrics.$monitoredMetricsList.hasClass('hidden')).toBeTruthy();
+    });
+  });
+
+  describe('populateActiveMetrics', () => {
+    let prometheusMetrics;
+
+    beforeEach(() => {
+      prometheusMetrics = new PrometheusMetrics('.js-prometheus-metrics-monitoring');
+    });
+
+    it('should show monitored metrics list', () => {
+      prometheusMetrics.populateActiveMetrics(metrics);
+
+      const $metricsListLi = prometheusMetrics.$monitoredMetricsList.find('li');
+
+      expect(prometheusMetrics.$monitoredMetricsLoading.hasClass('hidden')).toBeTruthy();
+      expect(prometheusMetrics.$monitoredMetricsList.hasClass('hidden')).toBeFalsy();
+
+      expect(prometheusMetrics.$monitoredMetricsCount.text()).toEqual('12');
+      expect($metricsListLi.length).toEqual(metrics.length);
+      expect($metricsListLi.first().find('.badge').text()).toEqual(`${metrics[0].active_metrics}`);
+    });
+
+    it('should show missing environment variables list', () => {
+      prometheusMetrics.populateActiveMetrics(missingVarMetrics);
+
+      expect(prometheusMetrics.$monitoredMetricsLoading.hasClass('hidden')).toBeTruthy();
+      expect(prometheusMetrics.$missingEnvVarPanel.hasClass('hidden')).toBeFalsy();
+
+      expect(prometheusMetrics.$missingEnvVarMetricCount.text()).toEqual('2');
+      expect(prometheusMetrics.$missingEnvVarPanel.find('li').length).toEqual(2);
+      expect(prometheusMetrics.$missingEnvVarPanel.find('.flash-container')).toBeDefined();
+    });
+  });
+
+  describe('loadActiveMetrics', () => {
+    let prometheusMetrics;
+
+    beforeEach(() => {
+      prometheusMetrics = new PrometheusMetrics('.js-prometheus-metrics-monitoring');
+    });
+
+    it('should show loader animation while response is being loaded and hide it when request is complete', (done) => {
+      const deferred = $.Deferred();
+      spyOn($, 'getJSON').and.returnValue(deferred.promise());
+
+      prometheusMetrics.loadActiveMetrics();
+
+      expect(prometheusMetrics.$monitoredMetricsLoading.hasClass('hidden')).toBeFalsy();
+      expect($.getJSON).toHaveBeenCalledWith(prometheusMetrics.activeMetricsEndpoint);
+
+      deferred.resolve({ data: metrics, success: true });
+
+      setTimeout(() => {
+        expect(prometheusMetrics.$monitoredMetricsLoading.hasClass('hidden')).toBeTruthy();
+        done();
+      });
+    });
+
+    it('should show empty state if response failed to load', (done) => {
+      const deferred = $.Deferred();
+      spyOn($, 'getJSON').and.returnValue(deferred.promise());
+      spyOn(prometheusMetrics, 'populateActiveMetrics');
+
+      prometheusMetrics.loadActiveMetrics();
+
+      deferred.reject();
+
+      setTimeout(() => {
+        expect(prometheusMetrics.$monitoredMetricsLoading.hasClass('hidden')).toBeTruthy();
+        expect(prometheusMetrics.$monitoredMetricsEmpty.hasClass('hidden')).toBeFalsy();
+        done();
+      });
+    });
+
+    it('should populate metrics list once response is loaded', (done) => {
+      const deferred = $.Deferred();
+      spyOn($, 'getJSON').and.returnValue(deferred.promise());
+      spyOn(prometheusMetrics, 'populateActiveMetrics');
+
+      prometheusMetrics.loadActiveMetrics();
+
+      deferred.resolve({ data: metrics, success: true });
+
+      setTimeout(() => {
+        expect(prometheusMetrics.populateActiveMetrics).toHaveBeenCalledWith(metrics);
+        done();
+      });
+    });
+  });
+});