feat: editable desired_num_licenses, license-creation on plans as action

Creates a simple django admin action to make the actual license count equal
the desired license count via SubscriptionPlanAdmin. The logic to create actual
licenses via subscription plan admin now takes the presence of last_freeze_timestamp into account.
No longer try to rectify desired-vs-actual on save of subscription plans via admin.
Makes desired_num_license editable via admin, so that our EstimatedCountLicensePagintion
doesn't completely lie when we manually remove licenses from a plan.
ENT-8905

license_manager/apps/subscriptions/admin.py

@@ -195,7 +195,6 @@ class SubscriptionPlanAdmin(DjangoQLSearchMixin, SimpleHistoryAdmin):
     read_only_fields = [
         'num_revocations_remaining',
         'num_licenses',
-        'desired_num_licenses',
         'expiration_processed',
         'customer_agreement',
         'last_freeze_timestamp',
@@ -204,6 +203,7 @@ class SubscriptionPlanAdmin(DjangoQLSearchMixin, SimpleHistoryAdmin):
     # Writable fields appear higher on the page.
     writable_fields = [
         'title',
+        'desired_num_licenses',
         'start_date',
         'expiration_date',
         'enterprise_catalog_uuid',
@@ -289,7 +289,10 @@ def get_fields(self, request, obj=None):
 
     autocomplete_fields = ['customer_agreement']
 
-    actions = ['process_unused_licenses_post_freeze']
+    actions = [
+        'process_unused_licenses_post_freeze',
+        'create_actual_licenses_action',
+    ]
 
     def get_queryset(self, request):
         return super().get_queryset(request).select_related(
@@ -342,6 +345,36 @@ def process_unused_licenses_post_freeze(self, request, queryset):
         except UnprocessableSubscriptionPlanFreezeError as exc:
             messages.add_message(request, messages.ERROR, exc)
 
+    @admin.action(
+        description='Create actual licenses to match desired number'
+    )
+    def create_actual_licenses_action(self, request, queryset):
+        """
+        Django action to make the actual number of License records associated with this
+        plan match the *desired* number of licenses for the plan.
+        """
+        for subscription_plan in queryset:
+            self._create_actual_licenses(subscription_plan)
+
+        messages.add_message(
+            request, messages.SUCCESS, 'Successfully created license records for selected Subscription Plans.',
+        )
+
+    def _create_actual_licenses(self, obj):
+        """
+        Provision any additional licenses if necessary, assuming that the plan
+        has not been "frozen"
+        """
+        if obj.desired_num_licenses and not obj.last_freeze_timestamp:
+            license_count_gap = obj.desired_num_licenses - obj.num_licenses
+            if license_count_gap > 0:
+                if license_count_gap <= PROVISION_LICENSES_BATCH_SIZE:
+                    # We can handle just one batch synchronously.
+                    SubscriptionPlan.increase_num_licenses(obj, license_count_gap)
+                else:
+                    # Multiple batches of licenses will need to be created, so provision them asynchronously.
+                    provision_licenses_task.delay(subscription_plan_uuid=obj.uuid)
+
     def save_model(self, request, obj, form, change):
         # Record change reason for simple history
         obj._change_reason = form.cleaned_data.get('change_reason')  # pylint: disable=protected-access
@@ -357,16 +390,9 @@ def save_model(self, request, obj, form, change):
 
         super().save_model(request, obj, form, change)
 
-        # Finally, provision any additional licenses if necessary.
-        if obj.desired_num_licenses:
-            license_count_gap = obj.desired_num_licenses - obj.num_licenses
-            if license_count_gap > 0:
-                if license_count_gap <= PROVISION_LICENSES_BATCH_SIZE:
-                    # We can handle just one batch synchronously.
-                    SubscriptionPlan.increase_num_licenses(obj, license_count_gap)
-                else:
-                    # Multiple batches of licenses will need to be created, so provision them asynchronously.
-                    provision_licenses_task.delay(subscription_plan_uuid=obj.uuid)
+        # Finally, if we're creating the model instance, go ahead and create the related license records.
+        if not change:
+            self._create_actual_licenses(obj)
 
 
 @admin.register(CustomerAgreement)

license_manager/apps/subscriptions/migrations/0067_editable_desired_num_licenses.py

@@ -0,0 +1,23 @@
+# Generated by Django 4.2.9 on 2024-05-08 14:27
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('subscriptions', '0066_license_subscription_plan_status_idx'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='historicalsubscriptionplan',
+            name='desired_num_licenses',
+            field=models.PositiveIntegerField(blank=True, help_text='Total number of licenses that should exist for this SubscriptionPlan. The total license count (provisioned asynchronously) will reach the desired amount eventually. Empty (NULL) means no attempts will be made to asynchronously provision licenses.', null=True, verbose_name='Desired Number of Licenses'),
+        ),
+        migrations.AlterField(
+            model_name='subscriptionplan',
+            name='desired_num_licenses',
+            field=models.PositiveIntegerField(blank=True, help_text='Total number of licenses that should exist for this SubscriptionPlan. The total license count (provisioned asynchronously) will reach the desired amount eventually. Empty (NULL) means no attempts will be made to asynchronously provision licenses.', null=True, verbose_name='Desired Number of Licenses'),
+        ),
+    ]

license_manager/apps/subscriptions/models.py

@@ -459,7 +459,6 @@ class SubscriptionPlan(TimeStampedModel):
     desired_num_licenses = models.PositiveIntegerField(
         blank=True,
         null=True,
-        editable=False,
         verbose_name="Desired Number of Licenses",
         help_text=(
             "Total number of licenses that should exist for this SubscriptionPlan. "

license_manager/apps/subscriptions/tests/test_admin.py

@@ -2,28 +2,28 @@
 from unittest import mock
 
 import pytest
+from django.contrib import messages
 from django.contrib.admin.sites import AdminSite
 from django.test import RequestFactory
 
 from license_manager.apps.subscriptions.admin import (
     CustomerAgreementAdmin,
     SubscriptionPlanAdmin,
 )
-from license_manager.apps.subscriptions.forms import SubscriptionPlanForm
 from license_manager.apps.subscriptions.models import (
     CustomerAgreement,
     SubscriptionPlan,
 )
 from license_manager.apps.subscriptions.tests.factories import (
     CustomerAgreementFactory,
-    PlanTypeFactory,
     SubscriptionPlanFactory,
     UserFactory,
 )
 from license_manager.apps.subscriptions.tests.utils import (
     make_bound_customer_agreement_form,
     make_bound_subscription_form,
 )
+from license_manager.apps.subscriptions.utils import localized_utcnow
 
 
 @pytest.mark.django_db
@@ -44,9 +44,10 @@ def test_licenses_subscription_creation():
 
 
 @pytest.mark.django_db
-def test_licenses_subscription_modification():
+@mock.patch('license_manager.apps.subscriptions.admin.messages.add_message')
+def test_subscription_licenses_create_action(mock_add_message):
     """
-    Verify that creating a SubscriptionPlan creates its associated Licenses after it is created.
+    Verify that running the create licenses action will create licenses.
     """
     # Setup an existing plan
     customer_agreement = CustomerAgreementFactory()
@@ -63,15 +64,39 @@ def test_licenses_subscription_modification():
 
     # doesn't really matter what we put for num_licenses in here, save_model
     # will read the desired number of license from the existing object on save.
-    form = make_bound_subscription_form(num_licenses=1)
+    form = make_bound_subscription_form(num_licenses=10)
     form.save()
 
     # save the form as a modify instead of create
     subscription_admin.save_model(request, subscription_plan, form, True)
+    subscription_plan.refresh_from_db()
+    # Desired number of licenses won't actually be created until we run the action
+    assert subscription_plan.licenses.count() == 0
+
+    # Now run the action...
+    subscription_admin.create_actual_licenses_action(
+        request,
+        SubscriptionPlan.objects.filter(uuid=subscription_plan.uuid),
+    )
+    subscription_plan.refresh_from_db()
+    # Actual number of licenses should now equal the desired number (ten)
+    assert subscription_plan.licenses.count() == 10
+
+    mock_add_message.assert_called_once_with(
+        request, messages.SUCCESS, 'Successfully created license records for selected Subscription Plans.',
+    )
 
-    # The save_model() method should determine that licenses need to be created,
-    # and then create them (synchronously in this case, since its a small number of licenses).
+    # check that freezing the plan means running the create licenses action has no effect
+    subscription_plan.last_freeze_timestamp = localized_utcnow()
+    subscription_plan.desired_num_licenses = 5000
+    subscription_plan.save()
+
+    subscription_admin.create_actual_licenses_action(
+        request,
+        SubscriptionPlan.objects.filter(uuid=subscription_plan.uuid),
+    )
     subscription_plan.refresh_from_db()
+    # Actual number of licenses should STILL equal 10, because the plan is frozen
     assert subscription_plan.licenses.count() == 10