Usage ping: Histogram for enabled integrations per project

Add metrics config with value type of `histogram`.
Add a changelog.

Fix attributes in metrics config

Move histogram to usage_activity_by_stage.monitor

changelogs/unreleased/263532-instrument-usage-ping-count-number-of-enabled-integrations-per-pro.yml

+---
+title: 'Usage ping: Histogram for enabled integrations per project'
+merge_request: 55782
+author:
+type: added

config/metrics/counts_all/20210309165717_projects_with_enabled_alert_integrations_histogram.yml

+---
+key_path: usage_activity_by_stage.monitor.projects_with_enabled_alert_integrations_histogram
+description: Histogram (buckets 1 to 100) of projects with at least 1 enabled integration.
+product_section: ops
+product_stage: monitor
+product_group: group::monitor
+product_category: incident_management
+value_type: object
+status: data_available
+milestone: "13.10"
+introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/55782
+time_frame: all
+data_source: database
+distribution:
+- ce
+- ee
+tier:
+- free
+- premium
+- ultimate

config/metrics/schema.json

@@ -22,7 +22,7 @@
     },
     "value_type": {
       "type": "string",
-      "enum": ["string", "number", "boolean"]
+      "enum": ["string", "number", "boolean", "object"]
     },
     "status": {
       "type": ["string"],

doc/development/usage_ping/dictionary.md

@@ -14840,6 +14840,18 @@ Status: `data_available`
 
 Tiers: `free`
 
+### `usage_activity_by_stage.monitor.projects_with_enabled_alert_integrations_histogram`
+
+Histogram (buckets 1 to 100) of projects with at least 1 enabled integration.
+
+[YAML definition](https://gitlab.com/gitlab-org/gitlab/-/blob/master/config/metrics/counts_all/20210309165717_projects_with_enabled_alert_integrations_histogram.yml)
+
+Group: `group::monitor`
+
+Status: `data_available`
+
+Tiers: `free`, `premium`, `ultimate`
+
 ### `usage_activity_by_stage.monitor.projects_with_error_tracking_enabled`
 
 Projects where error tracking is enabled

doc/development/usage_ping/metrics_dictionary.md

@@ -32,7 +32,7 @@ Each metric is defined in a separate YAML file consisting of a number of fields:
 | `product_stage`     | no       | The [stage](https://gitlab.com/gitlab-com/www-gitlab-com/blob/master/data/stages.yml) for the metric. |
 | `product_group`     | yes      | The [group](https://gitlab.com/gitlab-com/www-gitlab-com/blob/master/data/stages.yml) that owns the metric. |
 | `product_category`  | no       | The [product category](https://gitlab.com/gitlab-com/www-gitlab-com/blob/master/data/categories.yml) for the metric. |
-| `value_type`        | yes      | `string`; one of `string`, `number`, `boolean`.                                                               |
+| `value_type`        | yes      | `string`; one of `string`, `number`, `boolean`, `object`.                                                     |
 | `status`            | yes      | `string`; status of the metric, may be set to `data_available`, `planned`, `in_progress`, `implemented`, `not_used`, `deprecated` |
 | `time_frame`        | yes      | `string`; may be set to a value like `7d`, `28d`, `all`, `none`. |
 | `data_source`       | yes      | `string`; may be set to a value like `database`, `redis`, `redis_hll`, `prometheus`, `ruby`. |

ee/spec/lib/ee/gitlab/usage_data_spec.rb

@@ -134,14 +134,6 @@ RSpec.describe Gitlab::UsageData do
       expect(count_data[:epic_issues]).to eq(2)
     end
 
-    it 'has integer value for epic relationship level' do
-      expect(count_data[:epics_deepest_relationship_level]).to be_a_kind_of(Integer)
-    end
-
-    it 'has integer values for all counts' do
-      expect(count_data.values).to all(be_a_kind_of(Integer))
-    end
-
     it 'gathers security products usage data' do
       expect(count_data[:container_scanning_jobs]).to eq(1)
       expect(count_data[:dast_jobs]).to eq(1)

lib/gitlab/usage_data.rb

@@ -629,6 +629,9 @@ module Gitlab
 
       # rubocop: disable CodeReuse/ActiveRecord
       def usage_activity_by_stage_monitor(time_period)
+        # Calculate histogram only for overall as other time periods aren't available/useful here.
+        integrations_histogram = time_period.empty? ? histogram(::AlertManagement::HttpIntegration.active, :project_id, buckets: 1..100) : nil
+
         {
           clusters: distinct_count(::Clusters::Cluster.where(time_period), :user_id),
           clusters_applications_prometheus: cluster_applications_user_distinct_count(::Clusters::Applications::Prometheus, time_period),
@@ -638,8 +641,9 @@ module Gitlab
           projects_with_tracing_enabled: distinct_count(::Project.with_tracing_enabled.where(time_period), :creator_id),
           projects_with_error_tracking_enabled: distinct_count(::Project.with_enabled_error_tracking.where(time_period), :creator_id),
           projects_with_incidents: distinct_count(::Issue.incident.where(time_period), :project_id),
-          projects_with_alert_incidents: distinct_count(::Issue.incident.with_alert_management_alerts.where(time_period), :project_id)
-        }
+          projects_with_alert_incidents: distinct_count(::Issue.incident.with_alert_management_alerts.where(time_period), :project_id),
+          projects_with_enabled_alert_integrations_histogram: integrations_histogram
+        }.compact
       end
       # rubocop: enable CodeReuse/ActiveRecord
 

rubocop/rubocop-usage-data.yml

@@ -34,6 +34,7 @@ UsageData/LargeTable:
   CountMethods:
     - :count
     - :distinct_count
+    - :histogram
   AllowedMethods:
     - :arel_table
     - :minimum

spec/lib/gitlab/usage_data_spec.rb

@@ -384,12 +384,13 @@ RSpec.describe Gitlab::UsageData, :aggregate_failures do
       for_defined_days_back do
         user = create(:user, dashboard: 'operations')
         cluster = create(:cluster, user: user)
-        create(:project, creator: user)
+        project = create(:project, creator: user)
         create(:clusters_applications_prometheus, :installed, cluster: cluster)
         create(:project_tracing_setting)
         create(:project_error_tracking_setting)
         create(:incident)
         create(:incident, alert_management_alert: create(:alert_management_alert))
+        create(:alert_management_http_integration, :active, project: project)
       end
 
       expect(described_class.usage_activity_by_stage_monitor({})).to include(
@@ -399,10 +400,12 @@ RSpec.describe Gitlab::UsageData, :aggregate_failures do
         projects_with_tracing_enabled: 2,
         projects_with_error_tracking_enabled: 2,
         projects_with_incidents: 4,
-        projects_with_alert_incidents: 2
+        projects_with_alert_incidents: 2,
+        projects_with_enabled_alert_integrations_histogram: { '1' => 2 }
       )
 
-      expect(described_class.usage_activity_by_stage_monitor(described_class.last_28_days_time_period)).to include(
+      data_28_days = described_class.usage_activity_by_stage_monitor(described_class.last_28_days_time_period)
+      expect(data_28_days).to include(
         clusters: 1,
         clusters_applications_prometheus: 1,
         operations_dashboard_default_dashboard: 1,
@@ -411,6 +414,8 @@ RSpec.describe Gitlab::UsageData, :aggregate_failures do
         projects_with_incidents: 2,
         projects_with_alert_incidents: 1
       )
+
+      expect(data_28_days).not_to include(:projects_with_enabled_alert_integrations_histogram)
     end
   end
 
@@ -528,14 +533,14 @@ RSpec.describe Gitlab::UsageData, :aggregate_failures do
       expect(subject.keys).to include(*UsageDataHelpers::USAGE_DATA_KEYS)
     end
 
-    it 'gathers usage counts' do
+    it 'gathers usage counts', :aggregate_failures do
       count_data = subject[:counts]
 
       expect(count_data[:boards]).to eq(1)
       expect(count_data[:projects]).to eq(4)
-      expect(count_data.values_at(*UsageDataHelpers::SMAU_KEYS)).to all(be_an(Integer))
       expect(count_data.keys).to include(*UsageDataHelpers::COUNTS_KEYS)
       expect(UsageDataHelpers::COUNTS_KEYS - count_data.keys).to be_empty
+      expect(count_data.values).to all(be_a_kind_of(Integer))
     end
 
     it 'gathers usage counts correctly' do