feat(domain-core): distinguish between username and email

packages/analytics/src/Domain/Entity/AnalyticsEntity.ts

@@ -18,5 +18,5 @@ export class AnalyticsEntity {
     nullable: true,
   })
   @Index('email')
-  declare userEmail: string
+  declare username: string
 }

packages/analytics/src/Domain/Handler/SubscriptionCancelledEventHandler.ts

@@ -1,7 +1,7 @@
 import { DomainEventHandlerInterface, SubscriptionCancelledEvent } from '@standardnotes/domain-events'
 import { inject, injectable } from 'inversify'
 import { Logger } from 'winston'
-import { Email } from '@standardnotes/domain-core'
+import { Username } from '@standardnotes/domain-core'
 
 import TYPES from '../../Bootstrap/Types'
 import { AnalyticsActivity } from '../Analytics/AnalyticsActivity'
@@ -41,7 +41,7 @@ export class SubscriptionCancelledEventHandler implements DomainEventHandlerInte
       payedAmount: event.payload.payAmount,
       planName: SubscriptionPlanName.create(event.payload.subscriptionName).getValue(),
       subscriptionId: event.payload.subscriptionId,
-      userEmail: Email.create(event.payload.userEmail).getValue(),
+      username: Username.create(event.payload.userEmail).getValue(),
       userUuid,
     })
 

packages/analytics/src/Domain/Handler/SubscriptionExpiredEventHandler.ts

@@ -1,7 +1,7 @@
+import { Username } from '@standardnotes/domain-core'
 import { DomainEventHandlerInterface, SubscriptionExpiredEvent } from '@standardnotes/domain-events'
 import { inject, injectable } from 'inversify'
 import { Logger } from 'winston'
-import { Email } from '@standardnotes/domain-core'
 
 import TYPES from '../../Bootstrap/Types'
 import { AnalyticsActivity } from '../Analytics/AnalyticsActivity'
@@ -45,7 +45,7 @@ export class SubscriptionExpiredEventHandler implements DomainEventHandlerInterf
       payedAmount: event.payload.payAmount,
       planName: SubscriptionPlanName.create(event.payload.subscriptionName).getValue(),
       subscriptionId: event.payload.subscriptionId,
-      userEmail: Email.create(event.payload.userEmail).getValue(),
+      username: Username.create(event.payload.userEmail).getValue(),
       userUuid,
     })
 

packages/analytics/src/Domain/Handler/SubscriptionPurchasedEventHandler.ts

@@ -1,7 +1,7 @@
+import { Username } from '@standardnotes/domain-core'
 import { DomainEventHandlerInterface, SubscriptionPurchasedEvent } from '@standardnotes/domain-events'
 import { inject, injectable } from 'inversify'
 import { Logger } from 'winston'
-import { Email } from '@standardnotes/domain-core'
 
 import TYPES from '../../Bootstrap/Types'
 import { AnalyticsActivity } from '../Analytics/AnalyticsActivity'
@@ -69,7 +69,7 @@ export class SubscriptionPurchasedEventHandler implements DomainEventHandlerInte
       payedAmount: event.payload.payAmount,
       planName: SubscriptionPlanName.create(event.payload.subscriptionName).getValue(),
       subscriptionId: event.payload.subscriptionId,
-      userEmail: Email.create(event.payload.userEmail).getValue(),
+      username: Username.create(event.payload.userEmail).getValue(),
       userUuid,
     })
 

packages/analytics/src/Domain/Handler/SubscriptionRefundedEventHandler.ts

@@ -1,7 +1,7 @@
+import { Username } from '@standardnotes/domain-core'
 import { DomainEventHandlerInterface, SubscriptionRefundedEvent } from '@standardnotes/domain-events'
 import { inject, injectable } from 'inversify'
 import { Logger } from 'winston'
-import { Email } from '@standardnotes/domain-core'
 
 import TYPES from '../../Bootstrap/Types'
 import { AnalyticsActivity } from '../Analytics/AnalyticsActivity'
@@ -41,7 +41,7 @@ export class SubscriptionRefundedEventHandler implements DomainEventHandlerInter
       payedAmount: event.payload.payAmount,
       planName: SubscriptionPlanName.create(event.payload.subscriptionName).getValue(),
       subscriptionId: event.payload.subscriptionId,
-      userEmail: Email.create(event.payload.userEmail).getValue(),
+      username: Username.create(event.payload.userEmail).getValue(),
       userUuid,
     })
 

packages/analytics/src/Domain/Handler/SubscriptionRenewedEventHandler.ts

@@ -1,6 +1,6 @@
 import { DomainEventHandlerInterface, SubscriptionRenewedEvent } from '@standardnotes/domain-events'
 import { inject, injectable } from 'inversify'
-import { Email } from '@standardnotes/domain-core'
+import { Username } from '@standardnotes/domain-core'
 
 import TYPES from '../../Bootstrap/Types'
 import { GetUserAnalyticsId } from '../UseCase/GetUserAnalyticsId/GetUserAnalyticsId'
@@ -41,7 +41,7 @@ export class SubscriptionRenewedEventHandler implements DomainEventHandlerInterf
       payedAmount: event.payload.payAmount,
       planName: SubscriptionPlanName.create(event.payload.subscriptionName).getValue(),
       subscriptionId: event.payload.subscriptionId,
-      userEmail: Email.create(event.payload.userEmail).getValue(),
+      username: Username.create(event.payload.userEmail).getValue(),
       userUuid,
     })
 

packages/analytics/src/Domain/Handler/UserRegisteredEventHandler.ts

@@ -18,7 +18,7 @@ export class UserRegisteredEventHandler implements DomainEventHandlerInterface {
   async handle(event: UserRegisteredEvent): Promise<void> {
     let analyticsEntity = new AnalyticsEntity()
     analyticsEntity.userUuid = event.payload.userUuid
-    analyticsEntity.userEmail = event.payload.email
+    analyticsEntity.username = event.payload.email
     analyticsEntity = await this.analyticsEntityRepository.save(analyticsEntity)
 
     await this.analyticsStore.markActivity([AnalyticsActivity.Register], analyticsEntity.id, [

packages/analytics/src/Domain/Map/RevenueModificationMap.ts

@@ -1,5 +1,5 @@
 import { injectable } from 'inversify'
-import { Email, MapperInterface, UniqueEntityId } from '@standardnotes/domain-core'
+import { MapperInterface, UniqueEntityId, Username } from '@standardnotes/domain-core'
 
 import { TypeORMRevenueModification } from '../../Infra/TypeORM/TypeORMRevenueModification'
 import { MonthlyRevenue } from '../Revenue/MonthlyRevenue'
@@ -14,7 +14,7 @@ export class RevenueModificationMap implements MapperInterface<RevenueModificati
   toDomain(persistence: TypeORMRevenueModification): RevenueModification {
     const userOrError = User.create(
       {
-        email: Email.create(persistence.userEmail).getValue(),
+        username: Username.create(persistence.username).getValue(),
       },
       new UniqueEntityId(persistence.userUuid),
     )
@@ -70,7 +70,7 @@ export class RevenueModificationMap implements MapperInterface<RevenueModificati
     persistence.previousMonthlyRevenue = domain.props.previousMonthlyRevenue.value
     persistence.subscriptionId = subscription.id.toValue() as number
     persistence.subscriptionPlan = subscription.props.planName.value
-    persistence.userEmail = user.props.email.value
+    persistence.username = user.props.username.value
     persistence.userUuid = user.id.toString()
     persistence.createdAt = domain.props.createdAt
 

packages/analytics/src/Domain/Revenue/RevenueModification.spec.ts

@@ -1,4 +1,4 @@
-import { Email } from '@standardnotes/domain-core'
+import { Username } from '@standardnotes/domain-core'
 
 import { Subscription } from '../Subscription/Subscription'
 import { SubscriptionEventType } from '../Subscription/SubscriptionEventType'
@@ -19,7 +19,7 @@ describe('RevenueModification', () => {
       planName: SubscriptionPlanName.create('PRO_PLAN').getValue(),
     }).getValue()
     user = User.create({
-      email: Email.create('test@test.te').getValue(),
+      username: Username.create('test@test.te').getValue(),
     }).getValue()
   })
 

packages/analytics/src/Domain/UseCase/GetUserAnalyticsId/GetUserAnalyticsId.spec.ts

@@ -15,7 +15,7 @@ describe('GetUserAnalyticsId', () => {
     analyticsEntity = {
       id: 123,
       userUuid: '84c0f8e8-544a-4c7e-9adf-26209303bc1d',
-      userEmail: 'test@test.te',
+      username: 'test@test.te',
     } as jest.Mocked<AnalyticsEntity>
 
     analyticsEntityRepository = {} as jest.Mocked<AnalyticsEntityRepositoryInterface>

packages/analytics/src/Domain/UseCase/GetUserAnalyticsId/GetUserAnalyticsId.ts

@@ -1,5 +1,5 @@
 import { inject, injectable } from 'inversify'
-import { Email, Uuid } from '@standardnotes/domain-core'
+import { Username, Uuid } from '@standardnotes/domain-core'
 
 import TYPES from '../../../Bootstrap/Types'
 import { AnalyticsEntityRepositoryInterface } from '../../Entity/AnalyticsEntityRepositoryInterface'
@@ -28,7 +28,7 @@ export class GetUserAnalyticsId implements UseCaseInterface {
     return {
       analyticsId: analyticsEntity.id,
       userUuid: Uuid.create(analyticsEntity.userUuid).getValue(),
-      userEmail: Email.create(analyticsEntity.userEmail).getValue(),
+      username: Username.create(analyticsEntity.username).getValue(),
     }
   }
 }

packages/analytics/src/Domain/UseCase/GetUserAnalyticsId/GetUserAnalyticsIdResponse.ts

@@ -1,7 +1,7 @@
-import { Email, Uuid } from '@standardnotes/domain-core'
+import { Username, Uuid } from '@standardnotes/domain-core'
 
 export type GetUserAnalyticsIdResponse = {
   analyticsId: number
-  userEmail: Email
+  username: Username
   userUuid: Uuid
 }

packages/analytics/src/Domain/UseCase/SaveRevenueModification/SaveRevenueModification.spec.ts

@@ -1,7 +1,7 @@
 import 'reflect-metadata'
 
 import { TimerInterface } from '@standardnotes/time'
-import { Email, Result, Uuid } from '@standardnotes/domain-core'
+import { Result, Username, Uuid } from '@standardnotes/domain-core'
 
 import { MonthlyRevenue } from '../../Revenue/MonthlyRevenue'
 
@@ -45,7 +45,7 @@ describe('SaveRevenueModification', () => {
       payedAmount: 12.99,
       planName: SubscriptionPlanName.create('PRO_PLAN').getValue(),
       subscriptionId: 1234,
-      userEmail: Email.create('test@test.te').getValue(),
+      username: Username.create('test@test.te').getValue(),
       userUuid: Uuid.create('84c0f8e8-544a-4c7e-9adf-26209303bc1d').getValue(),
     })
 
@@ -63,7 +63,7 @@ describe('SaveRevenueModification', () => {
       payedAmount: 12.99,
       planName: SubscriptionPlanName.create('PRO_PLAN').getValue(),
       subscriptionId: 1234,
-      userEmail: Email.create('test@test.te').getValue(),
+      username: Username.create('test@test.te').getValue(),
       userUuid: Uuid.create('84c0f8e8-544a-4c7e-9adf-26209303bc1d').getValue(),
     })
 
@@ -81,7 +81,7 @@ describe('SaveRevenueModification', () => {
       payedAmount: 2,
       planName: SubscriptionPlanName.create('PRO_PLAN').getValue(),
       subscriptionId: 1234,
-      userEmail: Email.create('test@test.te').getValue(),
+      username: Username.create('test@test.te').getValue(),
       userUuid: Uuid.create('84c0f8e8-544a-4c7e-9adf-26209303bc1d').getValue(),
     })
 
@@ -101,7 +101,7 @@ describe('SaveRevenueModification', () => {
       payedAmount: 12.99,
       planName: SubscriptionPlanName.create('PRO_PLAN').getValue(),
       subscriptionId: 1234,
-      userEmail: Email.create('test@test.te').getValue(),
+      username: Username.create('test@test.te').getValue(),
       userUuid: Uuid.create('84c0f8e8-544a-4c7e-9adf-26209303bc1d').getValue(),
     })
 
@@ -122,7 +122,7 @@ describe('SaveRevenueModification', () => {
       payedAmount: 12.99,
       planName: SubscriptionPlanName.create('PRO_PLAN').getValue(),
       subscriptionId: 1234,
-      userEmail: Email.create('test@test.te').getValue(),
+      username: Username.create('test@test.te').getValue(),
       userUuid: Uuid.create('84c0f8e8-544a-4c7e-9adf-26209303bc1d').getValue(),
     })
 
@@ -142,7 +142,7 @@ describe('SaveRevenueModification', () => {
       payedAmount: 12.99,
       planName: SubscriptionPlanName.create('PRO_PLAN').getValue(),
       subscriptionId: 1234,
-      userEmail: Email.create('test@test.te').getValue(),
+      username: Username.create('test@test.te').getValue(),
       userUuid: Uuid.create('84c0f8e8-544a-4c7e-9adf-26209303bc1d').getValue(),
     })
 
@@ -162,7 +162,7 @@ describe('SaveRevenueModification', () => {
       payedAmount: 12.99,
       planName: SubscriptionPlanName.create('PRO_PLAN').getValue(),
       subscriptionId: 1234,
-      userEmail: Email.create('test@test.te').getValue(),
+      username: Username.create('test@test.te').getValue(),
       userUuid: Uuid.create('84c0f8e8-544a-4c7e-9adf-26209303bc1d').getValue(),
     })
 
@@ -182,7 +182,7 @@ describe('SaveRevenueModification', () => {
       payedAmount: 12.99,
       planName: SubscriptionPlanName.create('PRO_PLAN').getValue(),
       subscriptionId: 1234,
-      userEmail: Email.create('test@test.te').getValue(),
+      username: Username.create('test@test.te').getValue(),
       userUuid: Uuid.create('84c0f8e8-544a-4c7e-9adf-26209303bc1d').getValue(),
     })
 
@@ -202,7 +202,7 @@ describe('SaveRevenueModification', () => {
       payedAmount: 12.99,
       planName: SubscriptionPlanName.create('PRO_PLAN').getValue(),
       subscriptionId: 1234,
-      userEmail: Email.create('test@test.te').getValue(),
+      username: Username.create('test@test.te').getValue(),
       userUuid: Uuid.create('84c0f8e8-544a-4c7e-9adf-26209303bc1d').getValue(),
     })
 

packages/analytics/src/Domain/UseCase/SaveRevenueModification/SaveRevenueModification.ts

@@ -23,7 +23,7 @@ export class SaveRevenueModification implements DomainUseCaseInterface<RevenueMo
   async execute(dto: SaveRevenueModificationDTO): Promise<Result<RevenueModification>> {
     const userOrError = User.create(
       {
-        email: dto.userEmail,
+        username: dto.username,
       },
       new UniqueEntityId(dto.userUuid.value),
     )

packages/analytics/src/Domain/UseCase/SaveRevenueModification/SaveRevenueModificationDTO.ts

@@ -1,4 +1,4 @@
-import { Email, Uuid } from '@standardnotes/domain-core'
+import { Username, Uuid } from '@standardnotes/domain-core'
 
 import { SubscriptionEventType } from '../../Subscription/SubscriptionEventType'
 import { SubscriptionPlanName } from '../../Subscription/SubscriptionPlanName'
@@ -9,7 +9,7 @@ export interface SaveRevenueModificationDTO {
   planName: SubscriptionPlanName
   newSubscriber: boolean
   userUuid: Uuid
-  userEmail: Email
+  username: Username
   subscriptionId: number
   billingFrequency: number
 }

packages/analytics/src/Domain/User/User.spec.ts

@@ -1,11 +1,11 @@
-import { Email } from '@standardnotes/domain-core'
+import { Username } from '@standardnotes/domain-core'
 
 import { User } from './User'
 
 describe('User', () => {
   it('should create an entity', () => {
     const user = User.create({
-      email: Email.create('test@test.te').getValue(),
+      username: Username.create('test@test.te').getValue(),
     }).getValue()
 
     expect(user.id.toString()).toHaveLength(36)

packages/analytics/src/Domain/User/UserProps.ts

@@ -1,5 +1,5 @@
-import { Email } from '@standardnotes/domain-core'
+import { Username } from '@standardnotes/domain-core'
 
 export interface UserProps {
-  email: Email
+  username: Username
 }

packages/analytics/src/Infra/TypeORM/TypeORMRevenueModification.ts

@@ -18,7 +18,7 @@ export class TypeORMRevenueModification {
     length: 255,
   })
   @Index('email')
-  declare userEmail: string
+  declare username: string
 
   @Column({
     name: 'user_uuid',

packages/domain-core/src/Domain/Common/Email.spec.ts

@@ -9,7 +9,7 @@ describe('Email', () => {
   })
 
   it('should not create an invalid value object', () => {
-    const valueOrError = Email.create('')
+    const valueOrError = Email.create('foobar')
 
     expect(valueOrError.isFailed()).toBeTruthy()
   })

packages/domain-core/src/Domain/Common/Email.ts

@@ -1,6 +1,7 @@
 import { ValueObject } from '../Core/ValueObject'
 import { Result } from '../Core/Result'
 import { EmailProps } from './EmailProps'
+import { Validator } from '../Core/Validator'
 
 export class Email extends ValueObject<EmailProps> {
   get value(): string {
@@ -12,10 +13,11 @@ export class Email extends ValueObject<EmailProps> {
   }
 
   static create(email: string): Result<Email> {
-    if (!!email === false || email.length === 0) {
-      return Result.fail<Email>('Email cannot be empty')
-    } else {
-      return Result.ok<Email>(new Email({ value: email }))
+    const emailValidation = Validator.isValidEmail(email)
+    if (emailValidation.isFailed()) {
+      return Result.fail<Email>(emailValidation.getError())
     }
+
+    return Result.ok<Email>(new Email({ value: email }))
   }
 }

packages/domain-core/src/Domain/Common/RoleName.spec.ts

@@ -2,7 +2,7 @@ import { RoleName } from './RoleName'
 
 describe('RoleName', () => {
   it('should create a value object', () => {
-    const valueOrError = RoleName.create('PRO_USER')
+    const valueOrError = RoleName.create(RoleName.NAMES.ProUser)
 
     expect(valueOrError.isFailed()).toBeFalsy()
     expect(valueOrError.getValue().value).toEqual('PRO_USER')
@@ -17,9 +17,9 @@ describe('RoleName', () => {
   })
 
   it('should say if a role has more power or equal power to another role', () => {
-    const proUserRole = RoleName.create('PRO_USER').getValue()
-    const plusUserRole = RoleName.create('PLUS_USER').getValue()
-    const coreUser = RoleName.create('CORE_USER').getValue()
+    const proUserRole = RoleName.create(RoleName.NAMES.ProUser).getValue()
+    const plusUserRole = RoleName.create(RoleName.NAMES.PlusUser).getValue()
+    const coreUser = RoleName.create(RoleName.NAMES.CoreUser).getValue()
 
     expect(proUserRole.hasMoreOrEqualPowerTo(proUserRole)).toBeTruthy()
     expect(proUserRole.hasMoreOrEqualPowerTo(plusUserRole)).toBeTruthy()
@@ -32,5 +32,7 @@ describe('RoleName', () => {
     expect(coreUser.hasMoreOrEqualPowerTo(proUserRole)).toBeFalsy()
     expect(coreUser.hasMoreOrEqualPowerTo(plusUserRole)).toBeFalsy()
     expect(coreUser.hasMoreOrEqualPowerTo(coreUser)).toBeTruthy()
+
+    expect(RoleName.create(RoleName.NAMES.FilesBetaUser).getValue().hasMoreOrEqualPowerTo(coreUser)).toBeFalsy()
   })
 })

packages/domain-core/src/Domain/Common/RoleName.ts

@@ -3,7 +3,7 @@ import { Result } from '../Core/Result'
 import { RoleNameProps } from './RoleNameProps'
 
 export class RoleName extends ValueObject<RoleNameProps> {
-  private static readonly NAMES = {
+  static readonly NAMES = {
     CoreUser: 'CORE_USER',
     PlusUser: 'PLUS_USER',
     ProUser: 'PRO_USER',

packages/domain-core/src/Domain/Common/RoleNameCollection.spec.ts

@@ -3,7 +3,7 @@ import { RoleNameCollection } from './RoleNameCollection'
 
 describe('RoleNameCollection', () => {
   it('should create a value object', () => {
-    const role1 = RoleName.create('PRO_USER').getValue()
+    const role1 = RoleName.create(RoleName.NAMES.ProUser).getValue()
 
     const valueOrError = RoleNameCollection.create([role1])
 
@@ -12,23 +12,38 @@ describe('RoleNameCollection', () => {
   })
 
   it('should tell if collections are not equal', () => {
-    const roles1 = [RoleName.create('PRO_USER').getValue(), RoleName.create('PLUS_USER').getValue()]
+    const roles1 = [
+      RoleName.create(RoleName.NAMES.ProUser).getValue(),
+      RoleName.create(RoleName.NAMES.PlusUser).getValue(),
+    ]
 
-    const roles2 = RoleNameCollection.create([
-      RoleName.create('PRO_USER').getValue(),
-      RoleName.create('CORE_USER').getValue(),
+    let roles2 = RoleNameCollection.create([
+      RoleName.create(RoleName.NAMES.ProUser).getValue(),
+      RoleName.create(RoleName.NAMES.CoreUser).getValue(),
     ]).getValue()
 
-    const valueOrError = RoleNameCollection.create(roles1)
+    let valueOrError = RoleNameCollection.create(roles1)
+    expect(valueOrError.getValue().equals(roles2)).toBeFalsy()
+
+    roles2 = RoleNameCollection.create([
+      RoleName.create(RoleName.NAMES.ProUser).getValue(),
+      RoleName.create(RoleName.NAMES.PlusUser).getValue(),
+      RoleName.create(RoleName.NAMES.CoreUser).getValue(),
+    ]).getValue()
+
+    valueOrError = RoleNameCollection.create(roles1)
     expect(valueOrError.getValue().equals(roles2)).toBeFalsy()
   })
 
   it('should tell if collections are equal', () => {
-    const roles1 = [RoleName.create('PRO_USER').getValue(), RoleName.create('PLUS_USER').getValue()]
+    const roles1 = [
+      RoleName.create(RoleName.NAMES.ProUser).getValue(),
+      RoleName.create(RoleName.NAMES.PlusUser).getValue(),
+    ]
 
     const roles2 = RoleNameCollection.create([
-      RoleName.create('PRO_USER').getValue(),
-      RoleName.create('PLUS_USER').getValue(),
+      RoleName.create(RoleName.NAMES.ProUser).getValue(),
+      RoleName.create(RoleName.NAMES.PlusUser).getValue(),
     ]).getValue()
 
     const valueOrError = RoleNameCollection.create(roles1)
@@ -36,42 +51,62 @@ describe('RoleNameCollection', () => {
   })
 
   it('should tell if collection includes element', () => {
-    const roles1 = [RoleName.create('PRO_USER').getValue(), RoleName.create('PLUS_USER').getValue()]
+    const roles1 = [
+      RoleName.create(RoleName.NAMES.ProUser).getValue(),
+      RoleName.create(RoleName.NAMES.PlusUser).getValue(),
+    ]
 
     const valueOrError = RoleNameCollection.create(roles1)
-    expect(valueOrError.getValue().includes(RoleName.create('PRO_USER').getValue())).toBeTruthy()
+    expect(valueOrError.getValue().includes(RoleName.create(RoleName.NAMES.ProUser).getValue())).toBeTruthy()
   })
 
   it('should tell if collection does not includes element', () => {
-    const roles1 = [RoleName.create('PRO_USER').getValue(), RoleName.create('PLUS_USER').getValue()]
+    const roles1 = [
+      RoleName.create(RoleName.NAMES.ProUser).getValue(),
+      RoleName.create(RoleName.NAMES.PlusUser).getValue(),
+    ]
 
     const valueOrError = RoleNameCollection.create(roles1)
-    expect(valueOrError.getValue().includes(RoleName.create('CORE_USER').getValue())).toBeFalsy()
+    expect(valueOrError.getValue().includes(RoleName.create(RoleName.NAMES.CoreUser).getValue())).toBeFalsy()
   })
 
   it('should tell if collection has a role with more or equal power to', () => {
-    let roles = [RoleName.create('CORE_USER').getValue()]
+    let roles = [RoleName.create(RoleName.NAMES.CoreUser).getValue()]
     let valueOrError = RoleNameCollection.create(roles)
     let roleNames = valueOrError.getValue()
 
-    expect(roleNames.hasARoleNameWithMoreOrEqualPowerTo(RoleName.create('PLUS_USER').getValue())).toBeFalsy()
-    expect(roleNames.hasARoleNameWithMoreOrEqualPowerTo(RoleName.create('PRO_USER').getValue())).toBeFalsy()
-    expect(roleNames.hasARoleNameWithMoreOrEqualPowerTo(RoleName.create('CORE_USER').getValue())).toBeTruthy()
+    expect(
+      roleNames.hasARoleNameWithMoreOrEqualPowerTo(RoleName.create(RoleName.NAMES.PlusUser).getValue()),
+    ).toBeFalsy()
+    expect(roleNames.hasARoleNameWithMoreOrEqualPowerTo(RoleName.create(RoleName.NAMES.ProUser).getValue())).toBeFalsy()
+    expect(
+      roleNames.hasARoleNameWithMoreOrEqualPowerTo(RoleName.create(RoleName.NAMES.CoreUser).getValue()),
+    ).toBeTruthy()
 
-    roles = [RoleName.create('CORE_USER').getValue(), RoleName.create('PLUS_USER').getValue()]
+    roles = [RoleName.create(RoleName.NAMES.CoreUser).getValue(), RoleName.create(RoleName.NAMES.PlusUser).getValue()]
     valueOrError = RoleNameCollection.create(roles)
     roleNames = valueOrError.getValue()
 
-    expect(roleNames.hasARoleNameWithMoreOrEqualPowerTo(RoleName.create('PLUS_USER').getValue())).toBeTruthy()
-    expect(roleNames.hasARoleNameWithMoreOrEqualPowerTo(RoleName.create('PRO_USER').getValue())).toBeFalsy()
-    expect(roleNames.hasARoleNameWithMoreOrEqualPowerTo(RoleName.create('CORE_USER').getValue())).toBeTruthy()
+    expect(
+      roleNames.hasARoleNameWithMoreOrEqualPowerTo(RoleName.create(RoleName.NAMES.PlusUser).getValue()),
+    ).toBeTruthy()
+    expect(roleNames.hasARoleNameWithMoreOrEqualPowerTo(RoleName.create(RoleName.NAMES.ProUser).getValue())).toBeFalsy()
+    expect(
+      roleNames.hasARoleNameWithMoreOrEqualPowerTo(RoleName.create(RoleName.NAMES.CoreUser).getValue()),
+    ).toBeTruthy()
 
-    roles = [RoleName.create('PRO_USER').getValue(), RoleName.create('PLUS_USER').getValue()]
+    roles = [RoleName.create(RoleName.NAMES.ProUser).getValue(), RoleName.create(RoleName.NAMES.PlusUser).getValue()]
     valueOrError = RoleNameCollection.create(roles)
     roleNames = valueOrError.getValue()
 
-    expect(roleNames.hasARoleNameWithMoreOrEqualPowerTo(RoleName.create('PLUS_USER').getValue())).toBeTruthy()
-    expect(roleNames.hasARoleNameWithMoreOrEqualPowerTo(RoleName.create('PRO_USER').getValue())).toBeTruthy()
-    expect(roleNames.hasARoleNameWithMoreOrEqualPowerTo(RoleName.create('CORE_USER').getValue())).toBeTruthy()
+    expect(
+      roleNames.hasARoleNameWithMoreOrEqualPowerTo(RoleName.create(RoleName.NAMES.PlusUser).getValue()),
+    ).toBeTruthy()
+    expect(
+      roleNames.hasARoleNameWithMoreOrEqualPowerTo(RoleName.create(RoleName.NAMES.ProUser).getValue()),
+    ).toBeTruthy()
+    expect(
+      roleNames.hasARoleNameWithMoreOrEqualPowerTo(RoleName.create(RoleName.NAMES.CoreUser).getValue()),
+    ).toBeTruthy()
   })
 })

packages/domain-core/src/Domain/Common/Username.spec.ts

@@ -0,0 +1,16 @@
+import { Username } from './Username'
+
+describe('Username', () => {
+  it('should create a value object', () => {
+    const valueOrError = Username.create('test@test.te')
+
+    expect(valueOrError.isFailed()).toBeFalsy()
+    expect(valueOrError.getValue().value).toEqual('test@test.te')
+  })
+
+  it('should not create an invalid value object', () => {
+    const valueOrError = Username.create('')
+
+    expect(valueOrError.isFailed()).toBeTruthy()
+  })
+})

packages/domain-core/src/Domain/Common/Username.ts

@@ -0,0 +1,22 @@
+import { ValueObject } from '../Core/ValueObject'
+import { Result } from '../Core/Result'
+import { UsernameProps } from './UsernameProps'
+import { Validator } from '../Core/Validator'
+
+export class Username extends ValueObject<UsernameProps> {
+  get value(): string {
+    return this.props.value
+  }
+
+  private constructor(props: UsernameProps) {
+    super(props)
+  }
+
+  static create(username: string): Result<Username> {
+    if (Validator.isNotEmpty(username).isFailed()) {
+      return Result.fail<Username>('Username cannot be empty')
+    }
+
+    return Result.ok<Username>(new Username({ value: username }))
+  }
+}

packages/domain-core/src/Domain/Common/UsernameProps.ts

@@ -0,0 +1,3 @@
+export interface UsernameProps {
+  value: string
+}

packages/domain-core/src/Domain/Core/Validator.spec.ts

@@ -18,6 +18,31 @@ describe('Validator', () => {
     '../../escaped.sh',
   ]
 
+  const validEmails = [
+    'something@something.com',
+    'someone@localhost.localdomain',
+    'a/b@domain.com',
+    '{}@domain.com',
+    'karol+test@standardnotes.com',
+    "m*'!%@something.sa",
+    'tu!!7n7.ad##0!!!@company.ca',
+    '%@com.com',
+    "!#$%&'*+/=?^_`{|}~.-@com.com",
+    'someone@do-ma-in.com',
+    '""testlah""@example.com',
+  ]
+
+  const invalidEmails = [
+    'someone@127.0.0.1',
+    'a@b.b',
+    '',
+    null,
+    '.wooly@example.com',
+    'wo..oly@example.com',
+    'somebody@example',
+    'a@p.com',
+  ]
+
   it('should validate proper uuids', () => {
     for (const validUuid of validUuids) {
       expect(Validator.isValidUuid(validUuid).isFailed()).toBeFalsy()
@@ -29,4 +54,28 @@ describe('Validator', () => {
       expect(Validator.isValidUuid(invalidUuid as string).isFailed()).toBeTruthy()
     }
   })
+
+  it('should validate proper emails', () => {
+    for (const validEmail of validEmails) {
+      expect(Validator.isValidEmail(validEmail).isFailed()).toBeFalsy()
+    }
+  })
+
+  it('should not validate invalid emails', () => {
+    for (const invalidEmail of invalidEmails) {
+      expect(Validator.isValidEmail(invalidEmail as string).isFailed()).toBeTruthy()
+    }
+  })
+
+  it('should validate value if not empty', () => {
+    for (const value of [1, 'foobar', {}, 0]) {
+      expect(Validator.isNotEmpty(value).isFailed()).toBeFalsy()
+    }
+  })
+
+  it('should not validate value if empty', () => {
+    for (const value of [null, undefined, '', []]) {
+      expect(Validator.isNotEmpty(value).isFailed()).toBeTruthy()
+    }
+  })
 })

packages/domain-core/src/Domain/Core/Validator.ts

@@ -2,6 +2,8 @@ import { Result } from './Result'
 
 export class Validator {
   private static readonly UUID_REGEX = /^[0-9a-f]{8}-[0-9a-f]{4}-[0-5][0-9a-f]{3}-[089ab][0-9a-f]{3}-[0-9a-f]{12}$/i
+  private static readonly EMAIL_REGEX =
+    /^(([^<>()[\]\\.,;:\s@"]+(\.[^<>()[\]\\.,;:\s@"]+)*)|(".+"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/
 
   static isValidUuid(value: string): Result<string> {
     const matchesUuidRegex = String(value).toLowerCase().match(Validator.UUID_REGEX) !== null
@@ -11,4 +13,25 @@ export class Validator {
 
     return Result.fail(`Given value is not a valid uuid: ${value}`)
   }
+
+  static isValidEmail(value: string): Result<string> {
+    const matchesUuidRegex = String(value).toLowerCase().match(Validator.EMAIL_REGEX) !== null
+    if (matchesUuidRegex) {
+      return Result.ok()
+    }
+
+    return Result.fail(`Given value is not a valid email address: ${value}`)
+  }
+
+  static isNotEmpty(value: unknown): Result<string> {
+    if (value instanceof Array && value.length === 0) {
+      return Result.fail(`Given value is empty: ${value}`)
+    }
+
+    if (value === null || value === undefined || value === '') {
+      return Result.fail(`Given value is empty: ${value}`)
+    }
+
+    return Result.ok()
+  }
 }

packages/domain-core/src/Domain/index.ts

@@ -6,6 +6,8 @@ export * from './Common/RoleName'
 export * from './Common/RoleNameProps'
 export * from './Common/RoleNameCollection'
 export * from './Common/RoleNameCollectionProps'
+export * from './Common/Username'
+export * from './Common/UsernameProps'
 export * from './Common/Uuid'
 export * from './Common/UuidProps'