support: Set discounted price instead percentage for customers.

corporate/lib/activity.py

@@ -2,7 +2,7 @@
 from dataclasses import dataclass
 from datetime import datetime
 from decimal import Decimal
-from typing import Any, Callable, Dict, List, Optional, Sequence, Union
+from typing import Any, Callable, Dict, List, Optional, Sequence, Tuple, Union
 from urllib.parse import urlencode
 
 from django.conf import settings
@@ -20,10 +20,9 @@
     RemoteRealmBillingSession,
     RemoteServerBillingSession,
 )
-from corporate.models import Customer, CustomerPlan, LicenseLedger
+from corporate.models import CustomerPlan, LicenseLedger
 from zerver.lib.pysa import mark_sanitized
 from zerver.lib.url_encoding import append_url_query_string
-from zerver.lib.utils import assert_is_not_none
 from zerver.models import Realm
 from zilencer.models import (
     RemoteCustomerUserCount,
@@ -160,11 +159,12 @@ def remote_installation_support_link(hostname: str) -> Markup:
     return Markup('<a href="{url}"><i class="fa fa-gear"></i></a>').format(url=url)
 
 
-def get_plan_rate_percentage(discount: Optional[Decimal]) -> str:
-    if discount is None or discount == Decimal(0):
+def get_plan_rate_percentage(discount: Optional[str]) -> str:
+    # CustomerPlan.discount is a string field that stores the discount.
+    if discount is None or discount == "0":
         return "100%"
 
-    rate = 100 - discount
+    rate = 100 - Decimal(discount)
     if rate * 100 % 100 == 0:
         precision = 0
     else:
@@ -211,23 +211,11 @@ def get_remote_activity_plan_data(
     )
 
 
-def get_realms_with_default_discount_dict() -> Dict[str, Decimal]:
-    realms_with_default_discount: Dict[str, Any] = {}
-    customers = (
-        Customer.objects.exclude(default_discount=None)
-        .exclude(default_discount=0)
-        .exclude(realm=None)
-    )
-    for customer in customers:
-        assert customer.realm is not None
-        realms_with_default_discount[customer.realm.string_id] = assert_is_not_none(
-            customer.default_discount
-        )
-    return realms_with_default_discount
-
-
-def estimate_annual_recurring_revenue_by_realm() -> Dict[str, int]:  # nocoverage
+def get_estimated_arr_and_rate_by_realm() -> Tuple[Dict[str, int], Dict[str, str]]:  # nocoverage
+    # NOTE: Customers without a plan might still have a discount attached to them which
+    # are not included in `plan_rate`.
     annual_revenue = {}
+    plan_rate = {}
     plans = (
         CustomerPlan.objects.filter(
             status=CustomerPlan.ACTIVE,
@@ -254,7 +242,8 @@ def estimate_annual_recurring_revenue_by_realm() -> Dict[str, int]:  # nocoverag
         if plan.billing_schedule == CustomerPlan.BILLING_SCHEDULE_MONTHLY:
             renewal_cents *= 12
         annual_revenue[plan.customer.realm.string_id] = renewal_cents
-    return annual_revenue
+        plan_rate[plan.customer.realm.string_id] = get_plan_rate_percentage(plan.discount)
+    return annual_revenue, plan_rate
 
 
 def get_plan_data_by_remote_server() -> Dict[int, RemoteActivityPlanData]:  # nocoverage

corporate/lib/support.py

@@ -1,6 +1,5 @@
 from dataclasses import dataclass
 from datetime import datetime, timedelta
-from decimal import Decimal
 from typing import Optional, TypedDict, Union
 from urllib.parse import urlencode, urljoin, urlunsplit
 
@@ -16,6 +15,7 @@
     RemoteRealmBillingSession,
     RemoteServerBillingSession,
     get_configured_fixed_price_plan_offer,
+    get_price_per_license,
     get_push_status_for_remote_request,
     start_of_next_billing_cycle,
 )
@@ -58,7 +58,10 @@ class SponsorshipRequestDict(TypedDict):
 @dataclass
 class SponsorshipData:
     sponsorship_pending: bool = False
-    default_discount: Optional[Decimal] = None
+    monthly_discounted_price: Optional[int] = None
+    annual_discounted_price: Optional[int] = None
+    original_monthly_plan_price: Optional[int] = None
+    original_annual_plan_price: Optional[int] = None
     minimum_licenses: Optional[int] = None
     required_plan_tier: Optional[int] = None
     latest_sponsorship_request: Optional[SponsorshipRequestDict] = None
@@ -122,10 +125,24 @@ def get_realm_support_url(realm: Realm) -> str:
 
 def get_customer_sponsorship_data(customer: Customer) -> SponsorshipData:
     pending = customer.sponsorship_pending
-    discount = customer.default_discount
     licenses = customer.minimum_licenses
     plan_tier = customer.required_plan_tier
     sponsorship_request = None
+    monthly_discounted_price = None
+    annual_discounted_price = None
+    original_monthly_plan_price = None
+    original_annual_plan_price = None
+    if customer.monthly_discounted_price:
+        monthly_discounted_price = customer.monthly_discounted_price
+    if customer.annual_discounted_price:
+        annual_discounted_price = customer.annual_discounted_price
+    if plan_tier is not None:
+        original_monthly_plan_price = get_price_per_license(
+            plan_tier, CustomerPlan.BILLING_SCHEDULE_MONTHLY
+        )
+        original_annual_plan_price = get_price_per_license(
+            plan_tier, CustomerPlan.BILLING_SCHEDULE_ANNUAL
+        )
     if pending:
         last_sponsorship_request = (
             ZulipSponsorshipRequest.objects.filter(customer=customer).order_by("id").last()
@@ -151,7 +168,10 @@ def get_customer_sponsorship_data(customer: Customer) -> SponsorshipData:
 
     return SponsorshipData(
         sponsorship_pending=pending,
-        default_discount=discount,
+        monthly_discounted_price=monthly_discounted_price,
+        annual_discounted_price=annual_discounted_price,
+        original_monthly_plan_price=original_monthly_plan_price,
+        original_annual_plan_price=original_annual_plan_price,
         minimum_licenses=licenses,
         required_plan_tier=plan_tier,
         latest_sponsorship_request=sponsorship_request,

corporate/migrations/0043_remove_customer_default_discount_and_more.py

@@ -0,0 +1,89 @@
+# Generated by Django 5.0.5 on 2024-05-03 06:50
+
+from decimal import Decimal
+
+from django.db import migrations, models
+from django.db.backends.base.schema import BaseDatabaseSchemaEditor
+from django.db.migrations.state import StateApps
+
+# It's generally unsafe to import product code from migrations,
+# because the migration will be run with the **current** version of
+# that code, not the version at the time of the migration. But because
+# this migration will only be run for Zulip Cloud, this is OK.
+from corporate.lib.stripe import get_price_per_license
+
+
+def calculate_discounted_price_per_license(
+    original_price_per_license: int, discount: Decimal
+) -> int:
+    # There are no fractional cents in Stripe, so round down to nearest integer.
+    return int(float(original_price_per_license * (1 - discount / 100)) + 0.00001)
+
+
+def calculate_discounted_price(apps: StateApps, schema_editor: BaseDatabaseSchemaEditor) -> None:
+    """Migrates existing customers with a configured default discount to
+    instead have discounted prices for their configured required_plan_tier.
+
+    Does not operate on CustomerPlan fields, since those are already
+    resolved into a price.
+    """
+    BILLING_SCHEDULE_ANNUAL = 1
+    BILLING_SCHEDULE_MONTHLY = 2
+
+    Customer = apps.get_model("corporate", "Customer")
+    customers_to_update = []
+    for customer in Customer.objects.all():
+        if not customer.required_plan_tier or not customer.default_discount:
+            continue
+
+        annual_price_per_license = get_price_per_license(
+            customer.required_plan_tier, BILLING_SCHEDULE_ANNUAL
+        )
+        customer.annual_discounted_price = calculate_discounted_price_per_license(
+            annual_price_per_license, customer.default_discount
+        )
+        monthly_price_per_license = get_price_per_license(
+            customer.required_plan_tier, BILLING_SCHEDULE_MONTHLY
+        )
+        customer.monthly_discounted_price = calculate_discounted_price_per_license(
+            monthly_price_per_license, customer.default_discount
+        )
+        customers_to_update.append(customer)
+        print(
+            f"\nChanging price for {customer.id}: {customer.default_discount} => {customer.annual_discounted_price}/{customer.monthly_discounted_price}"
+        )
+
+    Customer.objects.bulk_update(
+        customers_to_update, ["annual_discounted_price", "monthly_discounted_price"]
+    )
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        ("corporate", "0042_invoice_is_created_for_free_trial_upgrade_and_more"),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name="customer",
+            name="annual_discounted_price",
+            field=models.IntegerField(default=0),
+        ),
+        migrations.AddField(
+            model_name="customer",
+            name="monthly_discounted_price",
+            field=models.IntegerField(default=0),
+        ),
+        # Populate the new discounted price fields based on existing default discount.
+        migrations.RunPython(calculate_discounted_price),
+        migrations.RemoveField(
+            model_name="customer",
+            name="default_discount",
+        ),
+        # This automatically converts the decimal to string so we don't need to do anything here.
+        migrations.AlterField(
+            model_name="customerplan",
+            name="discount",
+            field=models.TextField(null=True),
+        ),
+    ]

corporate/models.py

@@ -1,4 +1,3 @@
-from decimal import Decimal
 from enum import Enum
 from typing import Any, Dict, Optional, Union
 
@@ -27,10 +26,16 @@ class Customer(models.Model):
 
     stripe_customer_id = models.CharField(max_length=255, null=True, unique=True)
     sponsorship_pending = models.BooleanField(default=False)
-    # A percentage, like 85.
-    default_discount = models.DecimalField(decimal_places=4, max_digits=7, null=True)
+
+    # Discounted price for required_plan_tier in cents.
+    # We treat 0 as no discount. Not using `null` here keeps the
+    # checks simpler and avoids the cases where we forget to
+    # check for both `null` and 0.
+    monthly_discounted_price = models.IntegerField(default=0, null=False)
+    annual_discounted_price = models.IntegerField(default=0, null=False)
+
     minimum_licenses = models.PositiveIntegerField(null=True)
-    # Used for limiting a default_discount or a fixed_price
+    # Used for limiting discounted price or a fixed_price
     # to be used only for a particular CustomerPlan tier.
     required_plan_tier = models.SmallIntegerField(null=True)
     # Some non-profit organizations on manual license management pay
@@ -64,10 +69,15 @@ def __str__(self) -> str:
         else:
             return f"{self.remote_server!r} (with stripe_customer_id: {self.stripe_customer_id})"
 
-    def get_discount_for_plan_tier(self, plan_tier: int) -> Optional[Decimal]:
-        if self.required_plan_tier is None or self.required_plan_tier == plan_tier:
-            return self.default_discount
-        return None
+    def get_discounted_price_for_plan(self, plan_tier: int, schedule: int) -> Optional[int]:
+        if plan_tier != self.required_plan_tier:
+            return None
+
+        if schedule == CustomerPlan.BILLING_SCHEDULE_ANNUAL:
+            return self.annual_discounted_price
+
+        assert schedule == CustomerPlan.BILLING_SCHEDULE_MONTHLY
+        return self.monthly_discounted_price
 
 
 def get_customer_by_realm(realm: Realm) -> Optional[Customer]:
@@ -325,8 +335,10 @@ class CustomerPlan(AbstractCustomerPlan):
     # can't be set via the self-serve billing system.
     price_per_license = models.IntegerField(null=True)
 
-    # Discount that was applied. For display purposes only.
-    discount = models.DecimalField(decimal_places=4, max_digits=6, null=True)
+    # Discount for current `billing_schedule`. For display purposes only.
+    # Explicitly set to be TextField to avoid being used in calculations.
+    # NOTE: This discount can be different for annual and monthly schedules.
+    discount = models.TextField(null=True)
 
     # Initialized with the time of plan creation. Used for calculating
     # start of next billing cycle, next invoice date etc. This value

corporate/tests/test_activity_views.py

@@ -141,7 +141,7 @@ def test_activity(self, unused_mock: mock.Mock) -> None:
         user_profile.is_staff = True
         user_profile.save(update_fields=["is_staff"])
 
-        with self.assert_database_query_count(12):
+        with self.assert_database_query_count(11):
             result = self.client_get("/activity")
             self.assertEqual(result.status_code, 200)