corporate: Use Literal types for upgrade parameters.

Signed-off-by: Anders Kaseorg <anders@zulip.com>

corporate/lib/billing_types.py

@@ -0,0 +1,5 @@
+from typing import Literal
+
+BillingModality = Literal["send_invoice", "charge_automatically"]
+BillingSchedule = Literal["annual", "monthly"]
+LicenseManagement = Literal["automatic", "manual"]

corporate/lib/stripe.py

@@ -27,6 +27,7 @@ from django.utils.translation import gettext_lazy
 from django.utils.translation import override as override_language
 from typing_extensions import ParamSpec, override
 
+from corporate.lib.billing_types import BillingModality, BillingSchedule, LicenseManagement
 from corporate.models import (
     Customer,
     CustomerPlan,
@@ -90,10 +91,6 @@ MIN_INVOICED_LICENSES = 30
 MAX_INVOICED_LICENSES = 1000
 DEFAULT_INVOICE_DAYS_UNTIL_DUE = 15
 
-VALID_BILLING_MODALITY_VALUES = ["send_invoice", "charge_automatically"]
-VALID_BILLING_SCHEDULE_VALUES = ["annual", "monthly"]
-VALID_LICENSE_MANAGEMENT_VALUES = ["automatic", "manual"]
-
 CARD_CAPITALIZATION = {
     "amex": "American Express",
     "diners": "Diners Club",
@@ -232,19 +229,15 @@ def validate_licenses(
 
 
 def check_upgrade_parameters(
-    billing_modality: str,
-    schedule: str,
-    license_management: str | None,
+    billing_modality: BillingModality,
+    schedule: BillingSchedule,
+    license_management: LicenseManagement | None,
     licenses: int | None,
     seat_count: int,
     exempt_from_license_number_check: bool,
     min_licenses_for_plan: int,
 ) -> None:
-    if billing_modality not in VALID_BILLING_MODALITY_VALUES:  # nocoverage
-        raise BillingError("unknown billing_modality", "")
-    if schedule not in VALID_BILLING_SCHEDULE_VALUES:  # nocoverage
-        raise BillingError("unknown schedule")
-    if license_management not in VALID_LICENSE_MANAGEMENT_VALUES:  # nocoverage
+    if license_management is None:  # nocoverage
         raise BillingError("unknown license_management")
     validate_licenses(
         billing_modality == "charge_automatically",
@@ -541,11 +534,11 @@ class StripeCustomerData:
 
 @dataclass
 class UpgradeRequest:
-    billing_modality: str
-    schedule: str
+    billing_modality: BillingModality
+    schedule: BillingSchedule
     signed_seat_count: str
     salt: str
-    license_management: str | None
+    license_management: LicenseManagement | None
     licenses: int | None
     tier: int
     remote_server_plan_start_date: str | None
@@ -592,7 +585,7 @@ class SupportViewRequest(TypedDict, total=False):
     sponsorship_status: bool | None
     monthly_discounted_price: int | None
     annual_discounted_price: int | None
-    billing_modality: str | None
+    billing_modality: BillingModality | None
     plan_modification: str | None
     new_plan_tier: int | None
     minimum_licenses: int | None
@@ -3497,7 +3490,6 @@ class BillingSession(ABC):
             success_message = self.configure_temporary_courtesy_plan(temporary_plan_end_date)
         elif support_type == SupportType.update_billing_modality:
             assert support_request["billing_modality"] is not None
-            assert support_request["billing_modality"] in VALID_BILLING_MODALITY_VALUES
             charge_automatically = support_request["billing_modality"] == "charge_automatically"
             success_message = self.update_billing_modality_of_current_plan(charge_automatically)
         elif support_type == SupportType.update_plan_end_date:

corporate/views/support.py

@@ -23,6 +23,7 @@ from pydantic import AfterValidator, Json, NonNegativeInt
 from confirmation.models import Confirmation, confirmation_url
 from confirmation.settings import STATUS_USED
 from corporate.lib.activity import format_optional_datetime, remote_installation_stats_link
+from corporate.lib.billing_types import BillingModality
 from corporate.lib.stripe import (
     BILLING_SUPPORT_EMAIL,
     RealmBillingSession,
@@ -330,19 +331,14 @@ def check_update_max_invites(realm: Realm, new_max: int, default_max: int) -> bo
     return new_max > default_max
 
 
-VALID_MODIFY_PLAN_METHODS = Literal[
+ModifyPlan = Literal[
     "downgrade_at_billing_cycle_end",
     "downgrade_now_without_additional_licenses",
     "downgrade_now_void_open_invoices",
     "upgrade_plan_tier",
 ]
 
-VALID_STATUS_VALUES = Literal["active", "deactivated"]
-
-VALID_BILLING_MODALITY_VALUES = Literal[
-    "send_invoice",
-    "charge_automatically",
-]
+RemoteServerStatus = Literal["active", "deactivated"]
 
 SHARED_SUPPORT_CONTEXT = {
     "get_org_type_display_name": get_org_type_display_name,
@@ -363,11 +359,11 @@ def support(
     minimum_licenses: Json[NonNegativeInt] | None = None,
     required_plan_tier: Json[NonNegativeInt] | None = None,
     new_subdomain: str | None = None,
-    status: VALID_STATUS_VALUES | None = None,
-    billing_modality: VALID_BILLING_MODALITY_VALUES | None = None,
+    status: RemoteServerStatus | None = None,
+    billing_modality: BillingModality | None = None,
     sponsorship_pending: Json[bool] | None = None,
     approve_sponsorship: Json[bool] = False,
-    modify_plan: VALID_MODIFY_PLAN_METHODS | None = None,
+    modify_plan: ModifyPlan | None = None,
     scrub_realm: Json[bool] = False,
     delete_user_by_id: Json[NonNegativeInt] | None = None,
     query: Annotated[str | None, ApiParamConfig("q")] = None,
@@ -685,12 +681,12 @@ def remote_servers_support(
     sent_invoice_id: str | None = None,
     sponsorship_pending: Json[bool] | None = None,
     approve_sponsorship: Json[bool] = False,
-    billing_modality: VALID_BILLING_MODALITY_VALUES | None = None,
+    billing_modality: BillingModality | None = None,
     plan_end_date: Annotated[str, AfterValidator(lambda x: check_date("plan_end_date", x))]
     | None = None,
-    modify_plan: VALID_MODIFY_PLAN_METHODS | None = None,
+    modify_plan: ModifyPlan | None = None,
     delete_fixed_price_next_plan: Json[bool] = False,
-    remote_server_status: VALID_STATUS_VALUES | None = None,
+    remote_server_status: RemoteServerStatus | None = None,
     temporary_courtesy_plan: Annotated[
         str, AfterValidator(lambda x: check_date("temporary_courtesy_plan", x))
     ]

corporate/views/upgrade.py

@@ -1,19 +1,16 @@
 import logging
-from typing import Annotated
 
 from django.conf import settings
 from django.http import HttpRequest, HttpResponse, HttpResponseRedirect
 from django.shortcuts import render
 from pydantic import Json
 
+from corporate.lib.billing_types import BillingModality, BillingSchedule, LicenseManagement
 from corporate.lib.decorator import (
     authenticated_remote_realm_management_endpoint,
     authenticated_remote_server_management_endpoint,
 )
 from corporate.lib.stripe import (
-    VALID_BILLING_MODALITY_VALUES,
-    VALID_BILLING_SCHEDULE_VALUES,
-    VALID_LICENSE_MANAGEMENT_VALUES,
     BillingError,
     InitialUpgradeRequest,
     RealmBillingSession,
@@ -25,7 +22,6 @@ from corporate.models import CustomerPlan
 from zerver.decorator import require_organization_member, zulip_login_required
 from zerver.lib.response import json_success
 from zerver.lib.typed_endpoint import typed_endpoint
-from zerver.lib.typed_endpoint_validators import check_string_in_validator
 from zerver.models import UserProfile
 from zilencer.lib.remote_counts import MissingDataError
 
@@ -38,12 +34,11 @@ def upgrade(
     request: HttpRequest,
     user: UserProfile,
     *,
-    billing_modality: Annotated[str, check_string_in_validator(VALID_BILLING_MODALITY_VALUES)],
-    schedule: Annotated[str, check_string_in_validator(VALID_BILLING_SCHEDULE_VALUES)],
+    billing_modality: BillingModality,
+    schedule: BillingSchedule,
     signed_seat_count: str,
     salt: str,
-    license_management: Annotated[str, check_string_in_validator(VALID_LICENSE_MANAGEMENT_VALUES)]
-    | None = None,
+    license_management: LicenseManagement | None = None,
     licenses: Json[int] | None = None,
     tier: Json[int] = CustomerPlan.TIER_CLOUD_STANDARD,
 ) -> HttpResponse:
@@ -88,12 +83,11 @@ def remote_realm_upgrade(
     request: HttpRequest,
     billing_session: RemoteRealmBillingSession,
     *,
-    billing_modality: Annotated[str, check_string_in_validator(VALID_BILLING_MODALITY_VALUES)],
-    schedule: Annotated[str, check_string_in_validator(VALID_BILLING_SCHEDULE_VALUES)],
+    billing_modality: BillingModality,
+    schedule: BillingSchedule,
     signed_seat_count: str,
     salt: str,
-    license_management: Annotated[str, check_string_in_validator(VALID_LICENSE_MANAGEMENT_VALUES)]
-    | None = None,
+    license_management: LicenseManagement | None = None,
     licenses: Json[int] | None = None,
     remote_server_plan_start_date: str | None = None,
     tier: Json[int] = CustomerPlan.TIER_SELF_HOSTED_BUSINESS,
@@ -137,12 +131,11 @@ def remote_server_upgrade(
     request: HttpRequest,
     billing_session: RemoteServerBillingSession,
     *,
-    billing_modality: Annotated[str, check_string_in_validator(VALID_BILLING_MODALITY_VALUES)],
-    schedule: Annotated[str, check_string_in_validator(VALID_BILLING_SCHEDULE_VALUES)],
+    billing_modality: BillingModality,
+    schedule: BillingSchedule,
     signed_seat_count: str,
     salt: str,
-    license_management: Annotated[str, check_string_in_validator(VALID_LICENSE_MANAGEMENT_VALUES)]
-    | None = None,
+    license_management: LicenseManagement | None = None,
     licenses: Json[int] | None = None,
     remote_server_plan_start_date: str | None = None,
     tier: Json[int] = CustomerPlan.TIER_SELF_HOSTED_BUSINESS,