billing: Add cron job to run invoice_plans once a day.

Fixes #11960

puppet/zulip/files/cron.d/invoice-plans

@@ -0,0 +1,5 @@
+SHELL=/bin/bash
+PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin
+USER=zulip
+
+0 22 * * * zulip /home/zulip/deployments/current/manage.py invoice_plans

puppet/zulip_ops/manifests/prod_app_frontend.pp

@@ -38,6 +38,16 @@ class zulip_ops::prod_app_frontend {
     mode   => '0644',
     source => 'puppet:///modules/zulip/cron.d/calculate-first-visible-message-id',
   }
+
+  # TODO: This should ideally move to a prod_app_frontend_once.pp
+  file { '/etc/cron.d/invoice-plans':
+    ensure => file,
+    owner  => 'root',
+    group  => 'root',
+    mode   => '0644',
+    source => 'puppet:///modules/zulip/cron.d/invoice-plans',
+  }
+
   # Prod has our Apple Push Notifications Service private key at
   # /etc/ssl/django-private/apns-dist.pem
 }

zerver/tests/test_management_commands.py

@@ -389,3 +389,12 @@ class TestConvertMattermostData(ZulipTestCase):
             mattermost_data_dir=os.path.realpath(mm_fixtures),
             output_dir=os.path.realpath(output_dir),
         )
+
+class TestInvoicePlans(ZulipTestCase):
+    COMMAND_NAME = 'invoice_plans'
+
+    def test_if_command_calls_invoice_plans_as_needed(self) -> None:
+        with patch('zilencer.management.commands.invoice_plans.invoice_plans_as_needed') as m:
+            call_command(self.COMMAND_NAME)
+
+        m.assert_called_once()

zilencer/management/commands/invoice_plans.py

@@ -0,0 +1,14 @@
+from typing import Any
+
+from django.conf import settings
+
+from zerver.lib.management import ZulipBaseCommand
+if settings.BILLING_ENABLED:
+    from corporate.lib.stripe import invoice_plans_as_needed
+
+class Command(ZulipBaseCommand):
+    help = """Generates invoices for customers if needed."""
+
+    def handle(self, *args: Any, **options: Any) -> None:
+        if settings.BILLING_ENABLED:
+            invoice_plans_as_needed()