Expose seats_in_use in namespace entity

doc/api/namespaces.md

@@ -87,10 +87,12 @@ the `plan` parameter associated with a namespace:
 ]
 ```
 
-Users on GitLab.com will also see a `max_seats_used` parameter. `max_seats_used`
-is the highest number of users the group had.
+Users on GitLab.com will also see `max_seats_used` and `seats_in_use` parameters.
+`max_seats_used` is the highest number of users the group had. `seats_in_use` is
+the number of license seats currently being used. Both values are updated
+once a day.
 
-`max_seats_used` will be non-zero only for namespaces on paid plans.
+`max_seats_used` and `seats_in_use` will be non-zero only for namespaces on paid plans.
 
 ```json
 [
@@ -99,6 +101,7 @@ is the highest number of users the group had.
     "name": "user1",
     "billable_members_count": 2,
     "max_seats_used": 3,
+    "seats_in_use": 2,
     ...
   }
 ]
@@ -141,6 +144,7 @@ Example response:
     "members_count_with_descendants": 2,
     "billable_members_count": 2,
     "max_seats_used": 0,
+    "seats_in_use": 0,
     "plan": "default",
     "trial_ends_on": null,
     "trial": false
@@ -181,6 +185,7 @@ Example response:
   "members_count_with_descendants": 2,
   "billable_members_count": 2,
   "max_seats_used": 0,
+  "seats_in_use": 0,
   "plan": "default",
   "trial_ends_on": null,
   "trial": false
@@ -208,6 +213,7 @@ Example response:
   "members_count_with_descendants": 2,
   "billable_members_count": 2,
   "max_seats_used": 0,
+  "seats_in_use": 0,
   "plan": "default",
   "trial_ends_on": null,
   "trial": false

ee/changelogs/unreleased/al-update-namespace-api-entity.yml

+---
+title: Expose seats_in_use in namespace entity
+merge_request: 45316
+author:
+type: added

ee/lib/ee/api/entities/namespace.rb

@@ -18,6 +18,9 @@ module EE
           expose :billable_members_count do |namespace, options|
             namespace.billable_members_count(options[:requested_hosted_plan])
           end
+          expose :seats_in_use, if: has_gitlab_subscription do |namespace, _|
+            namespace.gitlab_subscription.seats_in_use
+          end
           expose :max_seats_used, if: has_gitlab_subscription do |namespace, _|
             namespace.gitlab_subscription.max_seats_used
           end

ee/spec/requests/api/namespaces_spec.rb

@@ -120,7 +120,7 @@ RSpec.describe API::Namespaces do
       before do
         group1.add_guest(user)
 
-        create(:gitlab_subscription, namespace: group1, max_seats_used: 1)
+        create(:gitlab_subscription, namespace: group1, max_seats_used: 1, seats_in_use: 1)
       end
 
       it "avoids additional N+1 database queries" do
@@ -146,6 +146,12 @@ RSpec.describe API::Namespaces do
 
         expect(json_response.first['max_seats_used']).to eq(1)
       end
+
+      it 'includes seats_in_use' do
+        get api("/namespaces", user)
+
+        expect(json_response.first['seats_in_use']).to eq(1)
+      end
     end
 
     context 'without gitlab subscription' do
@@ -156,6 +162,14 @@ RSpec.describe API::Namespaces do
           expect(resp.keys).not_to include('max_seats_used')
         end
       end
+
+      it 'does not include seats_in_use' do
+        get api("/namespaces", user)
+
+        json_response.each do |resp|
+          expect(resp.keys).not_to include('seats_in_use')
+        end
+      end
     end
   end