🐛 Ensure there is at least 1 owner in group

src/errors/errors.constants.ts

@@ -42,6 +42,8 @@ export const WHERE_PIPE_FORMAT = '400013: Invalid query format';
 export const OPTIONAL_INT_PIPE_NUMBER = '400014: $key should be a number';
 export const CURSOR_PIPE_FORMAT = '400015: Invalid cursor format';
 export const EMAIL_DELETE_PRIMARY = '400016: Cannot delete primary email';
+export const CANNOT_UPDATE_ROLE_SOLE_OWNER =
+  '400017: Cannot change the role of the only owner';
 
 export const EMAIL_USER_CONFLICT =
   '409001: User with this email already exists';

src/modules/memberships/memberships.service.ts

@@ -17,14 +17,15 @@ import {
 import {
   CANNOT_DELETE_SOLE_MEMBER,
   CANNOT_DELETE_SOLE_OWNER,
+  CANNOT_UPDATE_ROLE_SOLE_OWNER,
   MEMBERSHIP_NOT_FOUND,
   UNAUTHORIZED_RESOURCE,
 } from '../../errors/errors.constants';
 import { safeEmail } from '../../helpers/safe-email';
-import { Expose } from '../../providers/prisma/prisma.interface';
-import { AuthService } from '../auth/auth.service';
 import { MailService } from '../../providers/mail/mail.service';
+import { Expose } from '../../providers/prisma/prisma.interface';
 import { PrismaService } from '../../providers/prisma/prisma.service';
+import { AuthService } from '../auth/auth.service';
 import { CreateMembershipInput } from './memberships.interface';
 
 @Injectable()
@@ -111,6 +112,15 @@ export class MembershipsService {
     if (!testMembership) throw new NotFoundException(MEMBERSHIP_NOT_FOUND);
     if (testMembership.groupId !== groupId)
       throw new UnauthorizedException(UNAUTHORIZED_RESOURCE);
+    if (testMembership.role === 'OWNER' && data.role !== 'OWNER') {
+      const otherOwners = (
+        await this.prisma.memberships.findMany({
+          where: { group: { id: groupId }, role: 'OWNER' },
+        })
+      ).filter((i) => i.id !== id);
+      if (!otherOwners.length)
+        throw new BadRequestException(CANNOT_UPDATE_ROLE_SOLE_OWNER);
+    }
     const membership = await this.prisma.memberships.update({
       where: { id },
       data,