Add releases stats to group

Implement `Group#releases_count` and `Group#releases_count` to be used
in CI/CD dashboard.

Related to https://gitlab.com/gitlab-org/gitlab/-/issues/208947.

doc/api/graphql/reference/gitlab_schema.graphql

@@ -9454,6 +9454,11 @@ type Group {
   """
   shareWithGroupLock: Boolean
 
+  """
+  Group statistics
+  """
+  stats: GroupStats
+
   """
   Total storage limit of the root namespace in bytes
   """
@@ -9878,6 +9883,33 @@ type GroupPermissions {
   readGroup: Boolean!
 }
 
+"""
+Contains release-related statistics about a group
+"""
+type GroupReleaseStats {
+  """
+  Total number of releases in all descendant projects of the group. Will always
+  return `null` if `group_level_release_statistics` feature flag is disabled
+  """
+  releasesCount: Int
+
+  """
+  Percentage of the group's descendant projects that have at least one release.
+  Will always return `null` if `group_level_release_statistics` feature flag is disabled
+  """
+  releasesPercentage: Int
+}
+
+"""
+Contains statistics about a group
+"""
+type GroupStats {
+  """
+  Statistics related to releases within the group
+  """
+  releaseStats: GroupReleaseStats
+}
+
 """
 Health status of an issue or epic
 """

doc/api/graphql/reference/gitlab_schema.json

@@ -25803,6 +25803,20 @@
               "isDeprecated": false,
               "deprecationReason": null
             },
+            {
+              "name": "stats",
+              "description": "Group statistics",
+              "args": [
+
+              ],
+              "type": {
+                "kind": "OBJECT",
+                "name": "GroupStats",
+                "ofType": null
+              },
+              "isDeprecated": false,
+              "deprecationReason": null
+            },
             {
               "name": "storageSizeLimit",
               "description": "Total storage limit of the root namespace in bytes",
@@ -26988,6 +27002,74 @@
           "enumValues": null,
           "possibleTypes": null
         },
+        {
+          "kind": "OBJECT",
+          "name": "GroupReleaseStats",
+          "description": "Contains release-related statistics about a group",
+          "fields": [
+            {
+              "name": "releasesCount",
+              "description": "Total number of releases in all descendant projects of the group. Will always return `null` if `group_level_release_statistics` feature flag is disabled",
+              "args": [
+
+              ],
+              "type": {
+                "kind": "SCALAR",
+                "name": "Int",
+                "ofType": null
+              },
+              "isDeprecated": false,
+              "deprecationReason": null
+            },
+            {
+              "name": "releasesPercentage",
+              "description": "Percentage of the group's descendant projects that have at least one release. Will always return `null` if `group_level_release_statistics` feature flag is disabled",
+              "args": [
+
+              ],
+              "type": {
+                "kind": "SCALAR",
+                "name": "Int",
+                "ofType": null
+              },
+              "isDeprecated": false,
+              "deprecationReason": null
+            }
+          ],
+          "inputFields": null,
+          "interfaces": [
+
+          ],
+          "enumValues": null,
+          "possibleTypes": null
+        },
+        {
+          "kind": "OBJECT",
+          "name": "GroupStats",
+          "description": "Contains statistics about a group",
+          "fields": [
+            {
+              "name": "releaseStats",
+              "description": "Statistics related to releases within the group",
+              "args": [
+
+              ],
+              "type": {
+                "kind": "OBJECT",
+                "name": "GroupReleaseStats",
+                "ofType": null
+              },
+              "isDeprecated": false,
+              "deprecationReason": null
+            }
+          ],
+          "inputFields": null,
+          "interfaces": [
+
+          ],
+          "enumValues": null,
+          "possibleTypes": null
+        },
         {
           "kind": "ENUM",
           "name": "HealthStatus",

doc/api/graphql/reference/index.md

@@ -1447,6 +1447,7 @@ Autogenerated return type of EpicTreeReorder.
 | `requireTwoFactorAuthentication` | Boolean | Indicates if all users in this group are required to set up two-factor authentication |
 | `rootStorageStatistics` | RootStorageStatistics | Aggregated storage statistics of the namespace. Only available for root namespaces |
 | `shareWithGroupLock` | Boolean | Indicates if sharing a project with another group within this group is prevented |
+| `stats` | GroupStats | Group statistics |
 | `storageSizeLimit` | Float | Total storage limit of the root namespace in bytes |
 | `subgroupCreationLevel` | String | The permission level required to create subgroups within the group |
 | `temporaryStorageIncreaseEndsOn` | Time | Date until the temporary storage increase is active |
@@ -1486,6 +1487,23 @@ Represents a Group Membership.
 | ----- | ---- | ----------- |
 | `readGroup` | Boolean! | Indicates the user can perform `read_group` on this resource |
 
+### GroupReleaseStats
+
+Contains release-related statistics about a group.
+
+| Field | Type | Description |
+| ----- | ---- | ----------- |
+| `releasesCount` | Int | Total number of releases in all descendant projects of the group. Will always return `null` if `group_level_release_statistics` feature flag is disabled |
+| `releasesPercentage` | Int | Percentage of the group's descendant projects that have at least one release. Will always return `null` if `group_level_release_statistics` feature flag is disabled |
+
+### GroupStats
+
+Contains statistics about a group.
+
+| Field | Type | Description |
+| ----- | ---- | ----------- |
+| `releaseStats` | GroupReleaseStats | Statistics related to releases within the group |
+
 ### HttpIntegrationCreatePayload
 
 Autogenerated return type of HttpIntegrationCreate.

ee/app/graphql/ee/types/group_type.rb

@@ -73,6 +73,12 @@ module EE
               description: 'Represents the code coverage activity for this group',
               resolver: ::Resolvers::Ci::CodeCoverageActivitiesResolver,
               feature_flag: :group_coverage_data_report_graph
+
+        field :stats,
+              ::Types::GroupStatsType,
+              null: true,
+              description: 'Group statistics',
+              method: :itself
       end
     end
   end

ee/app/graphql/types/group_release_stats_type.rb

+# frozen_string_literal: true
+
+module Types
+  class GroupReleaseStatsType < BaseObject
+    graphql_name 'GroupReleaseStats'
+    description 'Contains release-related statistics about a group'
+
+    authorize :read_group_release_stats
+
+    field :releases_count, GraphQL::INT_TYPE, null: true,
+          description: 'Total number of releases in all descendant projects of the group. ' \
+                       'Will always return `null` if `group_level_release_statistics` feature flag is disabled'
+
+    def releases_count
+      object.releases_count if Feature.enabled?(:group_level_release_statistics, object, default_enabled: true)
+    end
+
+    field :releases_percentage, GraphQL::INT_TYPE, null: true,
+          description: "Percentage of the group's descendant projects that have at least one release. " \
+                       'Will always return `null` if `group_level_release_statistics` feature flag is disabled'
+
+    def releases_percentage
+      object.releases_percentage if Feature.enabled?(:group_level_release_statistics, object, default_enabled: true)
+    end
+  end
+end

ee/app/graphql/types/group_stats_type.rb

+# frozen_string_literal: true
+
+module Types
+  class GroupStatsType < BaseObject
+    graphql_name 'GroupStats'
+    description 'Contains statistics about a group'
+
+    authorize :read_group
+
+    field :release_stats, Types::GroupReleaseStatsType,
+          null: true, method: :itself,
+          description: 'Statistics related to releases within the group'
+  end
+end

ee/app/models/ee/group.rb

@@ -428,6 +428,23 @@ module EE
       members.count
     end
 
+    def releases_count
+      ::Release.by_namespace_id(self_and_descendants.select(:id)).count
+    end
+
+    def releases_percentage
+      calculate_sql = <<~SQL
+      (
+        COUNT(*) FILTER (WHERE EXISTS (SELECT 1 FROM releases WHERE releases.project_id = projects.id)) * 100.0 / GREATEST(COUNT(*), 1)
+      )::integer AS releases_percentage
+      SQL
+
+      self.class.count_by_sql(
+        ::Project.select(calculate_sql)
+        .where(namespace_id: self_and_descendants.select(:id)).to_sql
+      )
+    end
+
     private
 
     def custom_project_templates_group_allowed

ee/app/models/ee/release.rb

@@ -10,6 +10,8 @@ module EE
 
     prepended do
       include UsageStatistics
+
+      scope :by_namespace_id, -> (ns_id) { joins(:project).where(projects: { namespace_id: ns_id }) }
     end
   end
 end

ee/app/policies/ee/group_policy.rb

@@ -114,7 +114,10 @@ module EE
         enable :download_wiki_code
       end
 
-      rule { guest }.enable :read_wiki
+      rule { guest }.policy do
+        enable :read_wiki
+        enable :read_group_release_stats
+      end
 
       rule { reporter }.policy do
         enable :admin_list

ee/changelogs/unreleased/208947-group-release-stats.yml

+---
+title: Add releasesCount and releasesPercentage to Group GraphQL type
+merge_request: 47245
+author:
+type: added

ee/config/feature_flags/development/group_level_release_statistics.yml

+---
+name: group_level_release_statistics
+introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/47245
+rollout_issue_url: https://gitlab.com/gitlab-org/gitlab/-/issues/283962
+milestone: '13.6'
+type: development
+group: group::release
+default_enabled: true

ee/spec/graphql/ee/types/group_type_spec.rb

@@ -17,6 +17,7 @@ RSpec.describe GitlabSchema.types['Group'] do
   it { expect(described_class).to have_graphql_field(:vulnerabilities_count_by_day_and_severity) }
   it { expect(described_class).to have_graphql_field(:vulnerability_grades) }
   it { expect(described_class).to have_graphql_field(:code_coverage_activities) }
+  it { expect(described_class).to have_graphql_field(:stats) }
 
   describe 'timelogs field' do
     subject { described_class.fields['timelogs'] }

ee/spec/graphql/types/group_release_stats_type_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe GitlabSchema.types['GroupReleaseStats'] do
+  it { expect(described_class).to require_graphql_authorizations(:read_group_release_stats) }
+
+  it 'has the expected fields' do
+    expected_fields = %w[releasesCount releasesPercentage]
+
+    expect(described_class).to include_graphql_fields(*expected_fields)
+  end
+end

ee/spec/graphql/types/group_stats_type_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe GitlabSchema.types['GroupStats'] do
+  it { expect(described_class).to require_graphql_authorizations(:read_group) }
+
+  it 'has the expected fields' do
+    expected_fields = %w[releaseStats]
+
+    expect(described_class).to include_graphql_fields(*expected_fields)
+  end
+end

ee/spec/models/ee/release_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Release do
+  describe '.by_namespace_id' do
+    let_it_be(:group) { create(:group) }
+    let_it_be(:subgroup) { create(:group, parent: group) }
+    let_it_be(:project_in_group) { create(:project, group: group) }
+    let_it_be(:project_in_subgroup) { create(:project, group: subgroup) }
+    let_it_be(:unrelated_project) { create(:project) }
+
+    let_it_be(:release_in_group_project) { create(:release, project: project_in_group) }
+    let_it_be(:release_in_subgroup_project_1) { create(:release, project: project_in_subgroup) }
+    let_it_be(:release_in_subgroup_project_2) { create(:release, project: project_in_subgroup) }
+    let_it_be(:release_in_unrelated_project) { create(:release, project: unrelated_project) }
+
+    context 'when a single namespace id is passed' do
+      let(:ns_id) { group.id }
+
+      it 'returns releases associated to projects of the provided group' do
+        expect(described_class.by_namespace_id(ns_id)).to match_array([
+          release_in_group_project
+        ])
+      end
+    end
+
+    context 'when an array of namespace ids is passed' do
+      let(:ns_id) { group.self_and_descendants.select(:id) }
+
+      it 'returns releases associated to projects of all provided groups' do
+        expect(described_class.by_namespace_id(ns_id)).to match_array([
+          release_in_group_project,
+          release_in_subgroup_project_1,
+          release_in_subgroup_project_2
+        ])
+      end
+    end
+  end
+end

ee/spec/models/group_spec.rb

@@ -1174,4 +1174,49 @@ RSpec.describe Group do
 
     it { is_expected.to match([user.email]) }
   end
+
+  describe 'Releases Stats' do
+    context 'when there are no releases' do
+      describe '#releases_count' do
+        it 'returns 0' do
+          expect(group.releases_count).to eq(0)
+        end
+      end
+
+      describe '#releases_percentage' do
+        it 'returns 0 and does not attempt to divide by 0' do
+          expect(group.releases_percentage).to eq(0)
+        end
+      end
+    end
+
+    context 'when there are some releases' do
+      before do
+        subgroup_1 = create(:group, parent: group)
+        subgroup_2 = create(:group, parent: subgroup_1)
+
+        project_in_group = create(:project, group: group)
+        _project_in_subgroup_1 = create(:project, group: subgroup_1)
+        project_in_subgroup_2 = create(:project, group: subgroup_2)
+        project_in_unrelated_group = create(:project)
+
+        create(:release, project: project_in_group)
+        create(:release, project: project_in_subgroup_2)
+        create(:release, project: project_in_unrelated_group)
+      end
+
+      describe '#releases_count' do
+        it 'counts all releases for group and descendants' do
+          expect(group.releases_count).to eq(2)
+        end
+      end
+
+      describe '#releases_percentage' do
+        it 'calculates projects with releases percentage for group and descendants' do
+          # 2 out of 3 projects have releases
+          expect(group.releases_percentage).to eq(67)
+        end
+      end
+    end
+  end
 end

ee/spec/policies/group_policy_spec.rb

@@ -1242,4 +1242,40 @@ RSpec.describe GroupPolicy do
       end
     end
   end
+
+  describe ':read_group_release_stats' do
+    shared_examples 'read_group_release_stats permissions' do
+      context 'when user is logged out' do
+        let(:current_user) { nil }
+
+        it { is_expected.to be_disallowed(:read_group_release_stats) }
+      end
+
+      context 'when user is not a member of the group' do
+        let(:current_user) { create(:user) }
+
+        it { is_expected.to be_disallowed(:read_group_release_stats) }
+      end
+
+      context 'when user is guest' do
+        let(:current_user) { guest }
+
+        it { is_expected.to be_allowed(:read_group_release_stats) }
+      end
+    end
+
+    context 'when group is private' do
+      it_behaves_like 'read_group_release_stats permissions'
+    end
+
+    context 'when group is public' do
+      let(:group) { create(:group, :public) }
+
+      before do
+        group.add_guest(guest)
+      end
+
+      it_behaves_like 'read_group_release_stats permissions'
+    end
+  end
 end

ee/spec/requests/api/graphql/group_query_spec.rb

@@ -233,6 +233,122 @@ RSpec.describe 'getting group information' do
         current_user: user
       )
     end
+
+    context 'when loading release statistics' do
+      let_it_be(:guest_user) { create(:user) }
+      let_it_be(:public_user) { create(:user) }
+
+      let(:query_fields) do
+        <<~QUERY
+        stats {
+          releaseStats {
+            releasesCount
+            releasesPercentage
+          }
+        }
+        QUERY
+      end
+
+      let(:group_level_release_statistics) { true }
+
+      let(:query) do
+        graphql_query_for('group', { 'fullPath' => group.full_path }, query_fields)
+      end
+
+      let(:release_stats) do
+        graphql_data.with_indifferent_access.dig(:group, :stats, :releaseStats)
+      end
+
+      before do
+        stub_feature_flags(group_level_release_statistics: group_level_release_statistics)
+
+        group.add_guest(guest_user)
+
+        post_graphql(query, current_user: current_user)
+      end
+
+      shared_examples 'no access to release statistics' do
+        it 'returns data about release utilization within the group' do
+          expect(release_stats).to be_nil
+        end
+      end
+
+      shared_examples 'full access to release statistics' do
+        context 'when there are no releases' do
+          it 'returns 0 for both statistics' do
+            expect(release_stats).to match(
+              releasesCount: 0,
+              releasesPercentage: 0
+            )
+          end
+        end
+
+        context 'when there are some releases' do
+          let_it_be(:subgroup) { create(:group, :private, parent: group) }
+          let_it_be(:project_in_group) { create(:project, group: group) }
+          let_it_be(:project_in_subgroup) { create(:project, group: subgroup) }
+          let_it_be(:another_project_in_subgroup) { create(:project, group: subgroup) }
+          let_it_be(:project_in_unrelated_group) { create(:project) }
+          let_it_be(:release_1) { create(:release, project: project_in_group) }
+          let_it_be(:release_2) { create(:release, project: project_in_subgroup) }
+          let_it_be(:release_3) { create(:release, project: project_in_subgroup) }
+          let_it_be(:release_4) { create(:release, project: project_in_unrelated_group) }
+
+          it 'returns data about release utilization within the group' do
+            expect(release_stats).to match(
+              releasesCount: 3,
+              releasesPercentage: 67
+            )
+          end
+        end
+      end
+
+      shared_examples 'correct access to release statistics' do
+        context 'when the user is not logged in' do
+          let(:current_user) { nil }
+
+          it_behaves_like 'no access to release statistics'
+        end
+
+        context 'when the user is not a member of the group' do
+          let(:current_user) { public_user }
+
+          it_behaves_like 'no access to release statistics'
+        end
+
+        context 'when the user is at least a guest' do
+          let(:current_user) { guest_user }
+
+          it_behaves_like 'full access to release statistics'
+        end
+      end
+
+      context 'when the group is private' do
+        let_it_be(:group) { create(:group, :private) }
+
+        it_behaves_like 'correct access to release statistics'
+      end
+
+      context 'when the group is public' do
+        let_it_be(:group) { create(:group, :public) }
+
+        it_behaves_like 'correct access to release statistics'
+      end
+
+      context 'when the group_level_release_statistics feature flag is disabled' do
+        let_it_be(:group) { create(:group, :public) }
+
+        let(:current_user) { guest_user }
+        let(:group_level_release_statistics) { false }
+
+        it 'returns null for both statistics' do
+          expect(release_stats).to match(
+            releasesCount: nil,
+            releasesPercentage: nil
+          )
+        end
+      end
+    end
   end
 
   describe 'pagination' do