upgrade: Allow showing downgrade success message for legacy server.

corporate/lib/stripe.py

@@ -528,6 +528,7 @@ class UpgradeRequest:
 class InitialUpgradeRequest:
     manual_license_management: bool
     tier: int
+    success_message: str = ""
 
 
 @dataclass
@@ -634,6 +635,7 @@ class UpgradePageContext(TypedDict):
     salt: str
     seat_count: int
     signed_seat_count: str
+    success_message: str
 
 
 class SponsorshipRequestForm(forms.Form):
@@ -1801,6 +1803,7 @@ class BillingSession(ABC):
             "salt": salt,
             "seat_count": seat_count,
             "signed_seat_count": signed_seat_count,
+            "success_message": initial_upgrade_request.success_message,
         }
 
         return None, context

corporate/views/upgrade.py

@@ -233,10 +233,12 @@ def remote_server_upgrade_page(
     billing_session: RemoteServerBillingSession,
     *,
     manual_license_management: Json[bool] = False,
+    success_message: str = "",
 ) -> HttpResponse:  # nocoverage
     initial_upgrade_request = InitialUpgradeRequest(
         manual_license_management=manual_license_management,
         tier=CustomerPlan.TIER_SELF_HOSTED_BUSINESS,
+        success_message=success_message,
     )
     redirect_url, context = billing_session.get_initial_upgrade_context(initial_upgrade_request)
 

templates/corporate/upgrade.html

@@ -8,6 +8,11 @@
 {% block portico_content %}
 <div id="upgrade-page" class="register-account flex full-page">
     <div class="center-block new-style">
+        {% if success_message %}
+        <div class="alert alert-success billing-page-success" id="upgrade-success-message-top">
+            {{ success_message }}
+        </div>
+        {% endif %}
         <div class="pitch">
             <h1>
                 {% if free_trial_days %}

web/styles/portico/billing.css

@@ -593,6 +593,7 @@ input[name="licenses"] {
 
 #billing-sponsorship-pending-message-top,
 #sponsorship-status-success-message-top,
+#upgrade-success-message-top,
 #billing-success-message-top {
     display: block;
     text-align: center;