Add UI for handling the case when an enterprise has reached its maximum seat count

endpoints/api/__init__.py

@@ -66,6 +66,10 @@ class Unauthorized(ApiException):
       ApiException.__init__(self, 'insufficient_scope', 403, 'Unauthorized', payload)
 
 
+class ExceedsLicenseException(ApiException):
+  def __init__(self, payload=None):
+    ApiException.__init__(self, None, 402, 'Payment Required', payload)
+
 
 class NotFound(ApiException):
   def __init__(self, payload=None):
@@ -275,6 +279,10 @@ def request_error(exception=None, **kwargs):
   raise InvalidRequest(message, data)
 
 
+def license_error(exception=None):
+  raise ExceedsLicenseException()
+
+
 def log_action(kind, user_or_orgname, metadata=None, repo=None):
   if not metadata:
     metadata = {}

endpoints/api/user.py

@@ -8,7 +8,7 @@ from flask.ext.principal import identity_changed, AnonymousIdentity
 from app import app, billing as stripe, authentication
 from endpoints.api import (ApiResource, nickname, resource, validate_json_request, request_error,
                            log_action, internal_only, NotFound, require_user_admin,
-                           InvalidToken, require_scope, format_date, hide_if, show_if)
+                           InvalidToken, require_scope, format_date, hide_if, show_if, license_error)
 from endpoints.api.subscribe import subscribe
 from endpoints.common import common_login
 from data import model
@@ -193,6 +193,8 @@ class User(ApiResource):
       code = model.create_confirm_email_code(new_user)
       send_confirmation_email(new_user.username, new_user.email, code.code)
       return 'Created', 201
+    except model.TooManyUsersException as ex:
+      raise license_error(exception=ex)
     except model.DataModelException as ex:
       raise request_error(exception=ex)