Show friendly labels for capped duration values

Author: samejr

apps/webapp/app/services/sessionDuration.server.ts

@@ -5,7 +5,13 @@ import { commitSession } from "./sessionStorage.server";
 
 export const SESSION_ISSUED_AT_KEY = "session:issuedAt";
 
-export const DEFAULT_SESSION_DURATION_SECONDS = 60 * 60 * 24 * 365;
+// Months and years use standard Gregorian-calendar conversions (365.2425 days/yr,
+// 30.436875 days/month) so values produced by external "X months in seconds"
+// calculators map cleanly to a labeled option.
+const GREGORIAN_YEAR_SECONDS = 31_556_952; // 365.2425 * 86400
+const GREGORIAN_HALF_YEAR_SECONDS = 15_778_476;
+
+export const DEFAULT_SESSION_DURATION_SECONDS = GREGORIAN_YEAR_SECONDS;
 
 export type SessionDurationOption = {
   value: number;
@@ -18,8 +24,8 @@ export const SESSION_DURATION_OPTIONS: SessionDurationOption[] = [
   { value: 60 * 60, label: "1 hour" },
   { value: 60 * 60 * 24, label: "1 day" },
   { value: 60 * 60 * 24 * 30, label: "30 days" },
-  { value: 60 * 60 * 24 * 30 * 6, label: "6 months" },
-  { value: 60 * 60 * 24 * 365, label: "1 year" },
+  { value: GREGORIAN_HALF_YEAR_SECONDS, label: "6 months" },
+  { value: GREGORIAN_YEAR_SECONDS, label: "1 year" },
 ];
 
 export const ALLOWED_SESSION_DURATION_VALUES: ReadonlySet<number> = new Set(

apps/webapp/test/sessionDuration.test.ts

@@ -18,7 +18,7 @@ import {
 
 const oneHour = 60 * 60;
 const oneDay = 60 * 60 * 24;
-const oneYear = 60 * 60 * 24 * 365;
+const oneYear = DEFAULT_SESSION_DURATION_SECONDS;
 
 const sessionStorage = createCookieSessionStorage({
   cookie: { name: "__test_session", secrets: ["test"] },

internal-packages/database/prisma/migrations/20260428152919_use_gregorian_year_for_user_session_duration_default/migration.sql

@@ -0,0 +1,2 @@
+-- AlterTable
+ALTER TABLE "public"."User" ALTER COLUMN "sessionDuration" SET DEFAULT 31556952;

internal-packages/database/prisma/schema.prisma

@@ -54,9 +54,9 @@ model User {
   /// Hash of the last used code to prevent replay attacks
   mfaLastUsedCode      String?
 
-  /// Maximum session lifetime in seconds for this user. Default = 1 year.
+  /// Maximum session lifetime in seconds for this user. Default = 1 year (Gregorian).
   /// May be further restricted by Organization.maxSessionDuration on any of the user's orgs.
-  sessionDuration Int @default(31536000)
+  sessionDuration Int @default(31556952)
 
   invitationCode       InvitationCode?       @relation(fields: [invitationCodeId], references: [id])
   invitationCodeId     String?