feat: change email, export my data, delete account (with data anonymization)

internal/infrastructure/mailer/asyncDispatcher.go

@@ -0,0 +1,25 @@
+package mailer
+
+import (
+	domain "RenewCMS/internal/domain/mail"
+	"log"
+)
+
+type AsyncDispatcher struct{}
+
+func NewAsyncDispatcher() *AsyncDispatcher {
+	return &AsyncDispatcher{}
+}
+
+func (a *AsyncDispatcher) Dispatch(job func()) {
+	go func() {
+		defer func() {
+			if recovered := recover(); recovered != nil {
+				log.Println("panic in a background mail job:", recovered)
+			}
+		}()
+		job()
+	}()
+}
+
+var _ domain.Dispatcher = &AsyncDispatcher{}

internal/infrastructure/mailer/mailRepository.go

@@ -62,6 +62,12 @@ func subjectFor(templateName string, data any) string {
 		return "Verify your RenewCMS account"
 	case "password-reset":
 		return "Reset your RenewCMS password"
+	case "verify-new-email":
+		return "Confirm your new RenewCMS email address"
+	case "email-change-notice":
+		return "Your RenewCMS email address change was requested"
+	case "account-deleted":
+		return "Your RenewCMS account has been deleted"
 	}
 	return defaultSubject
 }

internal/infrastructure/mailer/templates/account-deleted.html

@@ -0,0 +1,62 @@
+<!DOCTYPE html>
+<html lang="en" xmlns="http://www.w3.org/1999/xhtml">
+<head>
+	<meta charset="utf-8">
+	<meta name="viewport" content="width=device-width, initial-scale=1">
+	<meta name="color-scheme" content="light dark">
+	<meta name="supported-color-schemes" content="light dark">
+	<title>Your account has been deleted</title>
+	<style>
+		body { margin: 0; padding: 0; width: 100%; -webkit-text-size-adjust: 100%; }
+		table { border-collapse: collapse; }
+		a { color: #111111; }
+		@media (max-width: 620px) {
+			.rc-card { padding: 28px 20px !important; }
+			.rc-btn a { display: block !important; }
+		}
+		@media (prefers-color-scheme: dark) {
+			.rc-bg { background-color: #0a0a0a !important; }
+			.rc-card { background-color: #111111 !important; border-color: #333333 !important; }
+			.rc-h1, .rc-word { color: #fafafa !important; }
+			.rc-text { color: #e6e4e0 !important; }
+			.rc-muted { color: #999999 !important; }
+			.rc-mark { border: 1px solid #444444 !important; }
+			.rc-btn td { background-color: #fafafa !important; }
+			.rc-btn a { background-color: #fafafa !important; color: #111111 !important; border-color: #fafafa !important; }
+			.rc-url { color: #e6e4e0 !important; background-color: #1a1a1a !important; }
+			.rc-rule { border-color: #333333 !important; }
+		}
+	</style>
+</head>
+<body class="rc-bg" style="margin:0;padding:0;background-color:#fafafa;">
+	<div style="display:none;max-height:0;overflow:hidden;opacity:0;color:transparent;">Your RenewCMS account was deleted and your personal data removed.</div>
+	<table role="presentation" width="100%" cellpadding="0" cellspacing="0" border="0" class="rc-bg" style="background-color:#fafafa;">
+		<tr>
+			<td align="center" style="padding:40px 12px;">
+				<table role="presentation" width="100%" cellpadding="0" cellspacing="0" border="0" style="max-width:600px;">
+					<tr>
+						<td style="padding:0 0 20px 0;">
+							<table role="presentation" cellpadding="0" cellspacing="0" border="0">
+								<tr>
+									<td class="rc-mark" width="32" height="32" align="center" valign="middle" bgcolor="#111111" style="width:32px;height:32px;background-color:#111111;color:#ffffff;font-family:Arial,Helvetica,sans-serif;font-size:19px;font-weight:bold;line-height:32px;">R</td>
+									<td class="rc-word" style="padding-left:10px;font-family:'IBM Plex Sans',Arial,Helvetica,sans-serif;font-size:17px;font-weight:600;color:#111111;">RenewCMS</td>
+								</tr>
+							</table>
+						</td>
+					</tr>
+					<tr>
+						<td class="rc-card" style="background-color:#ffffff;border:1px solid #e6e4e0;padding:40px;font-family:'IBM Plex Sans',Arial,Helvetica,sans-serif;">
+							<h1 class="rc-h1" style="margin:0 0 16px 0;font-size:24px;line-height:32px;font-weight:600;color:#111111;">Your account has been deleted</h1>
+							<p class="rc-text" style="margin:0 0 28px 0;font-size:16px;line-height:26px;color:#222222;">Your RenewCMS account at {{.Host}} has been deleted.</p>
+							<p class="rc-text rc-rule" style="margin:0;padding-top:0;border-top:0;font-size:14px;line-height:22px;color:#222222;">If you didn't ask for this, contact an administrator of {{.Host}}.</p>
+						</td>
+					</tr>
+					<tr>
+						<td class="rc-muted" style="padding:20px 0 0 0;font-family:'IBM Plex Sans',Arial,Helvetica,sans-serif;font-size:12px;line-height:18px;color:#666666;">RenewCMS · {{.Host}}</td>
+					</tr>
+				</table>
+			</td>
+		</tr>
+	</table>
+</body>
+</html>

internal/infrastructure/mailer/templates/email-change-notice.html

@@ -0,0 +1,69 @@
+<!DOCTYPE html>
+<html lang="en" xmlns="http://www.w3.org/1999/xhtml">
+<head>
+	<meta charset="utf-8">
+	<meta name="viewport" content="width=device-width, initial-scale=1">
+	<meta name="color-scheme" content="light dark">
+	<meta name="supported-color-schemes" content="light dark">
+	<title>Your email address change was requested</title>
+	<style>
+		body { margin: 0; padding: 0; width: 100%; -webkit-text-size-adjust: 100%; }
+		table { border-collapse: collapse; }
+		a { color: #111111; }
+		@media (max-width: 620px) {
+			.rc-card { padding: 28px 20px !important; }
+			.rc-btn a { display: block !important; }
+		}
+		@media (prefers-color-scheme: dark) {
+			.rc-bg { background-color: #0a0a0a !important; }
+			.rc-card { background-color: #111111 !important; border-color: #333333 !important; }
+			.rc-h1, .rc-word { color: #fafafa !important; }
+			.rc-text { color: #e6e4e0 !important; }
+			.rc-muted { color: #999999 !important; }
+			.rc-mark { border: 1px solid #444444 !important; }
+			.rc-btn td { background-color: #fafafa !important; }
+			.rc-btn a { background-color: #fafafa !important; color: #111111 !important; border-color: #fafafa !important; }
+			.rc-url { color: #e6e4e0 !important; background-color: #1a1a1a !important; }
+			.rc-rule { border-color: #333333 !important; }
+		}
+	</style>
+</head>
+<body class="rc-bg" style="margin:0;padding:0;background-color:#fafafa;">
+	<div style="display:none;max-height:0;overflow:hidden;opacity:0;color:transparent;">A change of email address was requested for your RenewCMS account. Nothing has changed yet.</div>
+	<table role="presentation" width="100%" cellpadding="0" cellspacing="0" border="0" class="rc-bg" style="background-color:#fafafa;">
+		<tr>
+			<td align="center" style="padding:40px 12px;">
+				<table role="presentation" width="100%" cellpadding="0" cellspacing="0" border="0" style="max-width:600px;">
+					<tr>
+						<td style="padding:0 0 20px 0;">
+							<table role="presentation" cellpadding="0" cellspacing="0" border="0">
+								<tr>
+									<td class="rc-mark" width="32" height="32" align="center" valign="middle" bgcolor="#111111" style="width:32px;height:32px;background-color:#111111;color:#ffffff;font-family:Arial,Helvetica,sans-serif;font-size:19px;font-weight:bold;line-height:32px;">R</td>
+									<td class="rc-word" style="padding-left:10px;font-family:'IBM Plex Sans',Arial,Helvetica,sans-serif;font-size:17px;font-weight:600;color:#111111;">RenewCMS</td>
+								</tr>
+							</table>
+						</td>
+					</tr>
+					<tr>
+						<td class="rc-card" style="background-color:#ffffff;border:1px solid #e6e4e0;padding:40px;font-family:'IBM Plex Sans',Arial,Helvetica,sans-serif;">
+							<h1 class="rc-h1" style="margin:0 0 16px 0;font-size:24px;line-height:32px;font-weight:600;color:#111111;">Your email address change was requested</h1>
+							<p class="rc-text" style="margin:0 0 28px 0;font-size:16px;line-height:26px;color:#222222;">A request was made to change the email address of the RenewCMS account {{.Username}} at {{.Host}} from this address to {{.NewEmail}}. Nothing has changed yet: you keep logging in with this address until the new one is confirmed.</p>
+							<table role="presentation" cellpadding="0" cellspacing="0" border="0" class="rc-btn">
+								<tr>
+									<td bgcolor="#111111" style="background-color:#111111;">
+										<a href="{{.Host}}/profile" target="_blank" style="display:inline-block;padding:14px 24px;border:1px solid #111111;background-color:#111111;color:#ffffff;font-family:'IBM Plex Sans',Arial,Helvetica,sans-serif;font-size:16px;font-weight:600;line-height:20px;text-decoration:none;text-align:center;">Review my profile</a>
+									</td>
+								</tr>
+							</table>
+							<p class="rc-text rc-rule" style="margin:28px 0 0 0;padding-top:20px;border-top:1px solid #e6e4e0;font-size:14px;line-height:22px;color:#222222;">If this was you, no action is needed. If it wasn't, log in, cancel the change from your profile and change your password.</p>
+						</td>
+					</tr>
+					<tr>
+						<td class="rc-muted" style="padding:20px 0 0 0;font-family:'IBM Plex Sans',Arial,Helvetica,sans-serif;font-size:12px;line-height:18px;color:#666666;">RenewCMS · {{.Host}}</td>
+					</tr>
+				</table>
+			</td>
+		</tr>
+	</table>
+</body>
+</html>

internal/infrastructure/mailer/templates/verify-new-email.html

@@ -0,0 +1,72 @@
+<!DOCTYPE html>
+<html lang="en" xmlns="http://www.w3.org/1999/xhtml">
+<head>
+	<meta charset="utf-8">
+	<meta name="viewport" content="width=device-width, initial-scale=1">
+	<meta name="color-scheme" content="light dark">
+	<meta name="supported-color-schemes" content="light dark">
+	<title>Confirm your new email address</title>
+	<style>
+		body { margin: 0; padding: 0; width: 100%; -webkit-text-size-adjust: 100%; }
+		table { border-collapse: collapse; }
+		a { color: #111111; }
+		@media (max-width: 620px) {
+			.rc-card { padding: 28px 20px !important; }
+			.rc-btn a { display: block !important; }
+		}
+		@media (prefers-color-scheme: dark) {
+			.rc-bg { background-color: #0a0a0a !important; }
+			.rc-card { background-color: #111111 !important; border-color: #333333 !important; }
+			.rc-h1, .rc-word { color: #fafafa !important; }
+			.rc-text { color: #e6e4e0 !important; }
+			.rc-muted { color: #999999 !important; }
+			.rc-mark { border: 1px solid #444444 !important; }
+			.rc-btn td { background-color: #fafafa !important; }
+			.rc-btn a { background-color: #fafafa !important; color: #111111 !important; border-color: #fafafa !important; }
+			.rc-url { color: #e6e4e0 !important; background-color: #1a1a1a !important; }
+			.rc-rule { border-color: #333333 !important; }
+		}
+	</style>
+</head>
+<body class="rc-bg" style="margin:0;padding:0;background-color:#fafafa;">
+	<div style="display:none;max-height:0;overflow:hidden;opacity:0;color:transparent;">Confirm this address to finish changing your RenewCMS email. The link expires in 2 hours.</div>
+	<table role="presentation" width="100%" cellpadding="0" cellspacing="0" border="0" class="rc-bg" style="background-color:#fafafa;">
+		<tr>
+			<td align="center" style="padding:40px 12px;">
+				<table role="presentation" width="100%" cellpadding="0" cellspacing="0" border="0" style="max-width:600px;">
+					<tr>
+						<td style="padding:0 0 20px 0;">
+							<table role="presentation" cellpadding="0" cellspacing="0" border="0">
+								<tr>
+									<td class="rc-mark" width="32" height="32" align="center" valign="middle" bgcolor="#111111" style="width:32px;height:32px;background-color:#111111;color:#ffffff;font-family:Arial,Helvetica,sans-serif;font-size:19px;font-weight:bold;line-height:32px;">R</td>
+									<td class="rc-word" style="padding-left:10px;font-family:'IBM Plex Sans',Arial,Helvetica,sans-serif;font-size:17px;font-weight:600;color:#111111;">RenewCMS</td>
+								</tr>
+							</table>
+						</td>
+					</tr>
+					<tr>
+						<td class="rc-card" style="background-color:#ffffff;border:1px solid #e6e4e0;padding:40px;font-family:'IBM Plex Sans',Arial,Helvetica,sans-serif;">
+							<h1 class="rc-h1" style="margin:0 0 16px 0;font-size:24px;line-height:32px;font-weight:600;color:#111111;">Confirm your new email address</h1>
+							<p class="rc-text" style="margin:0 0 28px 0;font-size:16px;line-height:26px;color:#222222;">Someone, hopefully you, asked to change the email address of the RenewCMS account {{.Username}} at {{.Host}} to this address. Confirm it to finish the change.</p>
+							<table role="presentation" cellpadding="0" cellspacing="0" border="0" class="rc-btn">
+								<tr>
+									<td bgcolor="#111111" style="background-color:#111111;">
+										<a href="{{.Host}}/account/email/confirm?c={{.VerificationCode}}" target="_blank" style="display:inline-block;padding:14px 24px;border:1px solid #111111;background-color:#111111;color:#ffffff;font-family:'IBM Plex Sans',Arial,Helvetica,sans-serif;font-size:16px;font-weight:600;line-height:20px;text-decoration:none;text-align:center;">Confirm new email address</a>
+									</td>
+								</tr>
+							</table>
+							<p class="rc-muted" style="margin:16px 0 0 0;font-size:14px;line-height:22px;color:#666666;">This link expires in 2 hours.</p>
+							<p class="rc-muted" style="margin:28px 0 8px 0;font-size:14px;line-height:22px;color:#666666;">If the button doesn't work, copy this address into your browser:</p>
+							<p class="rc-url" style="margin:0;padding:10px 12px;background-color:#f3f2f0;font-family:'IBM Plex Mono',Menlo,Consolas,monospace;font-size:13px;line-height:20px;color:#222222;word-break:break-all;">{{.Host}}/account/email/confirm?c={{.VerificationCode}}</p>
+							<p class="rc-text rc-rule" style="margin:28px 0 0 0;padding-top:20px;border-top:1px solid #e6e4e0;font-size:14px;line-height:22px;color:#222222;">If this wasn't you, ignore this email; nothing will change.</p>
+						</td>
+					</tr>
+					<tr>
+						<td class="rc-muted" style="padding:20px 0 0 0;font-family:'IBM Plex Sans',Arial,Helvetica,sans-serif;font-size:12px;line-height:18px;color:#666666;">RenewCMS · {{.Host}}</td>
+					</tr>
+				</table>
+			</td>
+		</tr>
+	</table>
+</body>
+</html>

internal/infrastructure/persistence/mappers/userMapper.go

@@ -47,6 +47,9 @@ func UserToDomain(m models.User) user.User {
 		VerificationCode:        nullableStringToDomain(m.VerificationCode),
 		VerificationExpiration:  m.VerificationExpiration,
 		PasswordResetExpiration: m.PasswordResetExpiration,
+		PendingEmail:            nullableStringToDomain(m.PendingEmail),
+		EmailChangeCode:         nullableStringToDomain(m.EmailChangeCode),
+		EmailChangeExpiration:   m.EmailChangeExpiration,
 		TokenVersion:            m.TokenVersion,
 		CreatedAt:               m.CreatedAt,
 		UpdatedAt:               m.UpdatedAt,
@@ -66,6 +69,9 @@ func UserToModel(a user.User) models.User {
 		VerificationCode:        DomainToNullableString(a.VerificationCode),
 		VerificationExpiration:  a.VerificationExpiration,
 		PasswordResetExpiration: a.PasswordResetExpiration,
+		PendingEmail:            DomainToNullableString(a.PendingEmail),
+		EmailChangeCode:         DomainToNullableString(a.EmailChangeCode),
+		EmailChangeExpiration:   a.EmailChangeExpiration,
 		TokenVersion:            a.TokenVersion,
 		CreatedAt:               a.CreatedAt,
 		UpdatedAt:               a.UpdatedAt,

internal/infrastructure/persistence/models/auditEventModel.go

@@ -10,8 +10,8 @@ type AuditEvent struct {
 	ActorType     string    `gorm:"not null;size:16;index:idx_audit_events_actor,priority:1"`
 	ActorID       *uint32   `gorm:"index:idx_audit_events_actor,priority:2"`
 	ActorName     string    `gorm:"not null;size:255"`
-	TargetType    string    `gorm:"not null;size:32"`
-	TargetID      string    `gorm:"not null;size:64"`
+	TargetType    string    `gorm:"not null;size:32;index:idx_audit_events_target,priority:1"`
+	TargetID      string    `gorm:"not null;size:64;index:idx_audit_events_target,priority:2"`
 	TargetName    string    `gorm:"not null;size:255"`
 	Outcome       string    `gorm:"not null;size:16"`
 	FailureReason *string   `gorm:"size:255"`

internal/infrastructure/persistence/models/userModel.go

@@ -17,6 +17,9 @@ type User struct {
 	VerificationCode        *string `gorm:"unique;size:255"`
 	VerificationExpiration  time.Time
 	PasswordResetExpiration time.Time
+	PendingEmail            *string `gorm:"size:255"`
+	EmailChangeCode         *string `gorm:"size:255"`
+	EmailChangeExpiration   time.Time
 	TokenVersion            uint32    `gorm:"default:0;not null"`
 	CreatedAt               time.Time `gorm:"autoCreateTime"`
 	UpdatedAt               time.Time `gorm:"autoUpdateTime"`

internal/infrastructure/persistence/repositories/accountEraser.go

@@ -0,0 +1,145 @@
+package persistence
+
+import (
+	"RenewCMS/internal/domain/author"
+	domain "RenewCMS/internal/domain/user"
+	entity "RenewCMS/internal/infrastructure/persistence/models"
+	"strings"
+
+	"gorm.io/gorm"
+	"gorm.io/gorm/clause"
+)
+
+const (
+	emptySocialLinks = "[]"
+	sqliteDialect    = "sqlite"
+)
+
+var contentionMarkers = []string{
+	"database is locked",
+	"sqlite_busy",
+	"deadlock",
+	"could not serialize",
+}
+
+type AccountEraser struct {
+	db *gorm.DB
+}
+
+var _ domain.Eraser = &AccountEraser{}
+
+func NewAccountEraser(db *gorm.DB) *AccountEraser {
+	return &AccountEraser{db}
+}
+
+func (e *AccountEraser) Erase(erasure domain.Erasure) error {
+	err := e.db.Transaction(func(tx *gorm.DB) error {
+		if err := e.recheckHolders(tx, erasure); err != nil {
+			return err
+		}
+		if err := tx.Where("user_id = ?", erasure.UserID).Delete(&entity.APIKey{}).Error; err != nil {
+			return err
+		}
+		ownAuthorID, err := e.releaseAuthor(tx, erasure.UserID)
+		if err != nil {
+			return err
+		}
+		if erasure.AvatarImageID != nil {
+			if err := tx.Delete(&entity.Image{}, *erasure.AvatarImageID).Error; err != nil {
+				return err
+			}
+		}
+		if err := NewAuditEventRepository(tx).AnonymiseUser(erasure.UserID, ownAuthorID, domain.DeletedUserName); err != nil {
+			return err
+		}
+		result := tx.Delete(&entity.User{}, erasure.UserID)
+		return deleteOrNotFound(result, domain.ErrUserNotFound)
+	})
+	if err != nil && len(erasure.GuardRoleIDs) > 0 && isContention(err) {
+		return domain.ErrAccountNotDeletable
+	}
+	return err
+}
+
+func isContention(err error) bool {
+	message := strings.ToLower(err.Error())
+	for _, marker := range contentionMarkers {
+		if strings.Contains(message, marker) {
+			return true
+		}
+	}
+	return false
+}
+
+func (e *AccountEraser) recheckHolders(tx *gorm.DB, erasure domain.Erasure) error {
+	if len(erasure.GuardRoleIDs) == 0 {
+		return nil
+	}
+	if err := lockRoles(tx, erasure.GuardRoleIDs); err != nil {
+		return err
+	}
+	var holders []entity.User
+	err := tx.Clauses(clause.Locking{Strength: "UPDATE"}).
+		Select("id").
+		Where("role_id IN ? AND is_verified = ? AND id <> ?", erasure.GuardRoleIDs, true, erasure.UserID).
+		Order("id ASC").
+		Find(&holders).Error
+	if err != nil {
+		return err
+	}
+	if len(holders) == 0 {
+		return domain.ErrAccountNotDeletable
+	}
+	return nil
+}
+
+func lockRoles(tx *gorm.DB, roleIDs []uint32) error {
+	if tx.Dialector.Name() == sqliteDialect {
+		return tx.Model(&entity.Role{}).Where("id IN ?", roleIDs).UpdateColumn("id", gorm.Expr("id")).Error
+	}
+	var locked []entity.Role
+	return tx.Clauses(clause.Locking{Strength: "UPDATE"}).Where("id IN ?", roleIDs).Order("id ASC").Find(&locked).Error
+}
+
+func (e *AccountEraser) releaseAuthor(tx *gorm.DB, userID uint32) (*uint32, error) {
+	var linked entity.Author
+	found := tx.Where("user_id = ?", userID).Limit(1).Find(&linked)
+	if found.Error != nil {
+		return nil, found.Error
+	}
+	if found.RowsAffected == 0 {
+		return nil, nil
+	}
+	ownID := linked.ID
+	var credits int64
+	if err := tx.Model(&entity.ArticleAuthor{}).Where("author_id = ?", linked.ID).Count(&credits).Error; err != nil {
+		return nil, err
+	}
+	if credits == 0 {
+		return &ownID, tx.Delete(&entity.Author{}, linked.ID).Error
+	}
+	slug, err := e.freeDeletedSlug(tx, linked.ID)
+	if err != nil {
+		return nil, err
+	}
+	return &ownID, tx.Model(&entity.Author{}).Where("id = ?", linked.ID).Updates(map[string]any{
+		"name":         author.DeletedName,
+		"slug":         slug,
+		"bio":          "",
+		"avatar_id":    nil,
+		"website":      nil,
+		"social_links": emptySocialLinks,
+		"user_id":      nil,
+	}).Error
+}
+
+func (e *AccountEraser) freeDeletedSlug(tx *gorm.DB, authorID uint32) (string, error) {
+	for attempt := 1; ; attempt++ {
+		candidate := author.DeletedSlugAttempt(authorID, attempt)
+		var taken int64
+		err := tx.Model(&entity.Author{}).Where("slug = ? AND id <> ?", candidate, authorID).Count(&taken).Error
+		if err != nil || taken == 0 {
+			return candidate, err
+		}
+	}
+}

internal/infrastructure/persistence/repositories/articleRepository.go

@@ -583,3 +583,18 @@ func (a *ArticleRepository) RepointImage(fromImageIDs []uint32, toImageID uint32
 }
 
 var _ domain.Repository = &ArticleRepository{}
+
+func (a *ArticleRepository) ListForAccount(creatorID uint32, authorID *uint32) ([]domain.Article, error) {
+	query := a.db.Model(&entity.Article{})
+	if authorID == nil {
+		query = query.Where("created_by = ?", creatorID)
+	} else {
+		credited := a.db.Model(&entity.ArticleAuthor{}).Select("article_id").Where("author_id = ?", *authorID)
+		query = query.Where("created_by = ? OR (is_online = ? AND id IN (?))", creatorID, true, credited)
+	}
+	var entityArticles []entity.Article
+	if err := query.Order("id asc").Find(&entityArticles).Error; err != nil {
+		return nil, err
+	}
+	return a.withAuthors(a.db, toDomainArticles(entityArticles))
+}

internal/infrastructure/persistence/repositories/auditEventRepository.go

@@ -5,6 +5,7 @@ import (
 	"RenewCMS/internal/infrastructure/persistence/mappers"
 	entity "RenewCMS/internal/infrastructure/persistence/models"
 	"slices"
+	"strconv"
 	"strings"
 	"time"
 
@@ -233,3 +234,38 @@ func (a *AuditEventRepository) DeleteOldest(limit int, before time.Time) (int, e
 	}
 	return removed, nil
 }
+
+const (
+	erasedParams  = "{}"
+	erasedChanges = "[]"
+	authorActions = "author.%"
+)
+
+func (a *AuditEventRepository) AnonymiseUser(userID uint32, ownAuthorID *uint32, name string) error {
+	userTargetID := strconv.FormatUint(uint64(userID), 10)
+	involved := "(actor_type = ? AND actor_id = ?) OR (target_type = ? AND target_id = ?)"
+	asActor := a.db.Model(&entity.AuditEvent{}).
+		Where("actor_type = ? AND actor_id = ?", string(audit.ActorUser), userID).
+		Updates(map[string]any{"actor_name": name, "ip": nil, "user_agent": nil})
+	if asActor.Error != nil {
+		return asActor.Error
+	}
+	asTarget := a.db.Model(&entity.AuditEvent{}).
+		Where("target_type = ? AND target_id = ?", audit.TargetUser, userTargetID).
+		Update("target_name", name)
+	if asTarget.Error != nil {
+		return asTarget.Error
+	}
+	if ownAuthorID != nil {
+		ownProfile := a.db.Model(&entity.AuditEvent{}).
+			Where("actor_type = ? AND actor_id = ? AND action LIKE ? AND target_type = ? AND target_id = ?",
+				string(audit.ActorUser), userID, authorActions, audit.TargetAuthor, strconv.FormatUint(uint64(*ownAuthorID), 10)).
+			Update("target_name", name)
+		if ownProfile.Error != nil {
+			return ownProfile.Error
+		}
+	}
+	return a.db.Model(&entity.AuditEvent{}).
+		Where(involved, string(audit.ActorUser), userID, audit.TargetUser, userTargetID).
+		Updates(map[string]any{"params": erasedParams, "changes": erasedChanges}).Error
+}

internal/infrastructure/persistence/repositories/entryRepository.go

@@ -154,3 +154,11 @@ func entriesToDomain(models []entity.Entry) ([]domain.Entry, error) {
 	}
 	return items, nil
 }
+
+func (e *EntryRepository) ListByCreator(creatorID uint32) ([]domain.Entry, error) {
+	var models []entity.Entry
+	if err := e.db.Where("created_by = ?", creatorID).Order("id asc").Find(&models).Error; err != nil {
+		return nil, err
+	}
+	return entriesToDomain(models)
+}

internal/infrastructure/persistence/repositories/imageRepository.go

@@ -160,3 +160,11 @@ func (i ImageRepository) UpdateMetadata(id uint32, metadata domain.Metadata) err
 }
 
 var _ domain.Repository = &ImageRepository{}
+
+func (i ImageRepository) ListByUploader(userID uint32) ([]domain.Image, error) {
+	var models []entity.Image
+	if err := i.db.Where("uploaded_by_id = ?", userID).Order("id asc").Find(&models).Error; err != nil {
+		return nil, err
+	}
+	return imagesToDomain(models), nil
+}

internal/infrastructure/persistence/repositories/userRepository.go

@@ -242,6 +242,80 @@ func (u *UserRepository) UpdateDisplayName(userId uint32, displayName string) (d
 	return mappers.UserToDomain(localUser), nil
 }
 
+func (u *UserRepository) IsEmailInUse(email string, exceptUserId uint32) (bool, error) {
+	return isEmailInUse(u.db, email, exceptUserId)
+}
+
+func isEmailInUse(db *gorm.DB, email string, exceptUserId uint32) (bool, error) {
+	var holders int64
+	err := db.Model(&entity.User{}).Where("LOWER(email) = LOWER(?) AND id <> ?", email, exceptUserId).Count(&holders).Error
+	return holders > 0, err
+}
+
+func (u *UserRepository) SetPendingEmailChange(userId uint32, pendingEmail string, code string, expiration time.Time) (domainUser.User, error) {
+	return u.updatePendingEmailChange(userId, map[string]any{
+		"pending_email":           mappers.DomainToNullableString(pendingEmail),
+		"email_change_code":       mappers.DomainToNullableString(code),
+		"email_change_expiration": expiration,
+	})
+}
+
+func (u *UserRepository) ClearPendingEmailChange(userId uint32) (domainUser.User, error) {
+	return u.updatePendingEmailChange(userId, clearedEmailChange())
+}
+
+func clearedEmailChange() map[string]any {
+	return map[string]any{
+		"pending_email":           nil,
+		"email_change_code":       nil,
+		"email_change_expiration": time.Time{},
+	}
+}
+
+func (u *UserRepository) updatePendingEmailChange(userId uint32, columns map[string]any) (domainUser.User, error) {
+	result := u.db.Model(&entity.User{}).Where("id = ?", userId).Updates(columns)
+	if result.Error != nil {
+		return domainUser.User{}, result.Error
+	}
+	return u.Get(userId)
+}
+
+func (u *UserRepository) ConfirmEmailChange(userId uint32, pendingEmail string, code string, now time.Time) (domainUser.User, error) {
+	taken, err := isEmailInUse(u.db, pendingEmail, userId)
+	if err != nil {
+		return domainUser.User{}, err
+	}
+	columns := clearedEmailChange()
+	if !taken {
+		columns["email"] = pendingEmail
+	}
+	result := pendingChangeOf(u.db, userId, pendingEmail, code).Where("email_change_expiration > ?", now).Updates(columns)
+	if result.Error != nil && isUniqueViolation(result.Error) {
+		return domainUser.User{}, u.refuseTakenAddress(userId, pendingEmail, code)
+	}
+	if result.Error != nil {
+		return domainUser.User{}, result.Error
+	}
+	if result.RowsAffected == 0 {
+		return domainUser.User{}, domainUser.ErrInvalidEmailChangeCode
+	}
+	if taken {
+		return domainUser.User{}, domainUser.ErrEmailUnavailable
+	}
+	return u.Get(userId)
+}
+
+func (u *UserRepository) refuseTakenAddress(userId uint32, pendingEmail string, code string) error {
+	if err := pendingChangeOf(u.db, userId, pendingEmail, code).Updates(clearedEmailChange()).Error; err != nil {
+		return err
+	}
+	return domainUser.ErrEmailUnavailable
+}
+
+func pendingChangeOf(db *gorm.DB, userId uint32, pendingEmail string, code string) *gorm.DB {
+	return db.Model(&entity.User{}).Where("id = ? AND pending_email = ? AND email_change_code = ?", userId, pendingEmail, code)
+}
+
 func (u *UserRepository) UpdateRole(id uint32, from uint32, to uint32, assignedBy uint32) (domainUser.User, error) {
 	err := u.db.Transaction(func(tx *gorm.DB) error {
 		query := tx.Model(&entity.User{}).Where("id = ? AND EXISTS (SELECT 1 FROM roles WHERE id = ?)", id, to)

internal/infrastructure/useCases/CancelEmailChange.go

@@ -0,0 +1,34 @@
+package useCases
+
+import (
+	"RenewCMS/internal/domain/audit"
+	"RenewCMS/internal/domain/user"
+	"context"
+)
+
+type CancelEmailChangeUseCase struct {
+	userRepository user.Repository
+	recorder       audit.Recorder
+}
+
+func NewCancelEmailChangeUseCase(userRepository user.Repository, recorder audit.Recorder) *CancelEmailChangeUseCase {
+	return &CancelEmailChangeUseCase{userRepository, recorder}
+}
+
+func (u *CancelEmailChangeUseCase) CancelEmailChange(ctx context.Context, userId uint32) error {
+	account, err := u.userRepository.Get(userId)
+	if err != nil {
+		return err
+	}
+	if account.PendingEmail == "" {
+		return nil
+	}
+	event := audit.NewEvent(audit.ActionUserCancelEmail, audit.CategoryUsers)
+	event.Target = userTarget(account)
+	if _, err := u.userRepository.ClearPendingEmailChange(userId); err != nil {
+		recordFailure(ctx, u.recorder, event, err)
+		return err
+	}
+	u.recorder.Record(ctx, event)
+	return nil
+}

internal/infrastructure/useCases/ConfirmEmailChange.go

@@ -0,0 +1,52 @@
+package useCases
+
+import (
+	"RenewCMS/internal/domain/audit"
+	"RenewCMS/internal/domain/hash"
+	"RenewCMS/internal/domain/user"
+	"context"
+	"time"
+)
+
+type ConfirmEmailChangeUseCase struct {
+	userRepository user.Repository
+	hasher         hash.Hasher
+	now            func() time.Time
+	recorder       audit.Recorder
+}
+
+func NewConfirmEmailChangeUseCase(userRepository user.Repository, hasher hash.Hasher, now func() time.Time, recorder audit.Recorder) *ConfirmEmailChangeUseCase {
+	return &ConfirmEmailChangeUseCase{userRepository, hasher, now, recorder}
+}
+
+func (u *ConfirmEmailChangeUseCase) ConfirmEmailChange(ctx context.Context, userId uint32, code string) (string, error) {
+	account, err := u.userRepository.Get(userId)
+	if err != nil {
+		return "", err
+	}
+	event := audit.NewEvent(audit.ActionUserConfirmEmail, audit.CategoryUsers)
+	event.Target = userTarget(account)
+	event.Security = true
+	if !u.accepts(account, code) {
+		recordFailure(ctx, u.recorder, event, user.ErrInvalidEmailChangeCode)
+		return "", user.ErrInvalidEmailChangeCode
+	}
+
+	updated, err := u.userRepository.ConfirmEmailChange(userId, account.PendingEmail, account.EmailChangeCode, u.now())
+	if err != nil {
+		recordFailure(ctx, u.recorder, event, err)
+		return "", err
+	}
+	u.recorder.Record(ctx, event)
+	return updated.Email, nil
+}
+
+func (u *ConfirmEmailChangeUseCase) accepts(account user.User, code string) bool {
+	if account.PendingEmail == "" || account.EmailChangeCode == "" {
+		return false
+	}
+	if u.now().After(account.EmailChangeExpiration) {
+		return false
+	}
+	return u.hasher.Compare(account.EmailChangeCode, code) == nil
+}

internal/infrastructure/useCases/DeleteOwnAccount.go

@@ -0,0 +1,199 @@
+package useCases
+
+import (
+	"RenewCMS/internal/domain/audit"
+	"RenewCMS/internal/domain/author"
+	"RenewCMS/internal/domain/hash"
+	"RenewCMS/internal/domain/image"
+	"RenewCMS/internal/domain/mail"
+	"RenewCMS/internal/domain/role"
+	"RenewCMS/internal/domain/user"
+	"context"
+	"errors"
+	"log"
+	"slices"
+	"time"
+)
+
+const accountDeletedTemplateName = "account-deleted"
+
+type MailAccountDeletedData struct {
+	Host string
+}
+
+type sessionRevoker interface {
+	Revoke(id string, expiresAt time.Time) error
+}
+
+type DeleteOwnAccountUseCase struct {
+	users          user.Repository
+	roles          role.Repository
+	hasher         hash.Hasher
+	eraser         user.Eraser
+	sessions       sessionRevoker
+	mailRepository mail.Repository
+	dispatcher     mail.Dispatcher
+	publicURL      string
+	recorder       audit.Recorder
+	authors        author.Repository
+	images         image.Repository
+	usage          *GetMediaUsageUseCase
+	avatars        mediaRemover
+}
+
+type DeleteOwnAccountCommand struct {
+	UserID           uint32
+	CurrentPassword  string
+	SessionID        string
+	SessionExpiresAt time.Time
+}
+
+func NewDeleteOwnAccountUseCase(users user.Repository, roles role.Repository, hasher hash.Hasher, eraser user.Eraser, sessions sessionRevoker, mailRepository mail.Repository, dispatcher mail.Dispatcher, publicURL string, recorder audit.Recorder, authors author.Repository, images image.Repository, usage *GetMediaUsageUseCase, storage image.Storage, variantFiles image.VariantFileRepository) *DeleteOwnAccountUseCase {
+	return &DeleteOwnAccountUseCase{users, roles, hasher, eraser, sessions, mailRepository, dispatcher, publicURL, recorder, authors, images, usage, newMediaRemover(images, storage, variantFiles)}
+}
+
+func (u *DeleteOwnAccountUseCase) Delete(ctx context.Context, command DeleteOwnAccountCommand) error {
+	account, err := u.users.Get(command.UserID)
+	if err != nil {
+		return err
+	}
+	event := audit.NewEvent(audit.ActionUserDeleteAccount, audit.CategoryUsers)
+	event.Target = userTarget(account)
+	event.Security = true
+
+	guard, err := u.check(account, command)
+	if err != nil {
+		recordFailure(ctx, u.recorder, event, err)
+		return err
+	}
+	avatar, err := u.removableAvatar(account)
+	if err != nil {
+		recordFailure(ctx, u.recorder, event, err)
+		return err
+	}
+	erasure := user.Erasure{UserID: account.ID, GuardRoleIDs: guard}
+	if avatar != nil {
+		erasure.AvatarImageID = &avatar.ID
+	}
+	if err := u.eraser.Erase(erasure); err != nil {
+		recordFailure(ctx, u.recorder, event, err)
+		return err
+	}
+	u.discardAvatar(avatar)
+	u.revoke(command)
+	u.notify(account)
+	u.recordSuccess(ctx, account)
+	return nil
+}
+
+func (u *DeleteOwnAccountUseCase) check(account user.User, command DeleteOwnAccountCommand) ([]uint32, error) {
+	if u.hasher.Compare(account.Password, command.CurrentPassword) != nil {
+		return nil, user.ErrWrongPassword
+	}
+	guard, label, err := u.guardedRoles(account)
+	if err != nil || len(guard) == 0 {
+		return nil, err
+	}
+	hasOther, err := u.hasOtherHolder(account.ID, guard)
+	if err != nil {
+		return nil, err
+	}
+	if !hasOther {
+		return nil, user.LastAdminError{Role: label}
+	}
+	return guard, nil
+}
+
+func (u *DeleteOwnAccountUseCase) guardedRoles(account user.User) ([]uint32, string, error) {
+	owner, err := builtInRole(u.roles, role.OwnerName)
+	if err != nil {
+		return nil, "", err
+	}
+	if account.RoleID == owner.ID {
+		return []uint32{owner.ID}, user.LastRoleOwner, nil
+	}
+	admin, err := builtInRole(u.roles, role.AdminName)
+	if err != nil {
+		return nil, "", err
+	}
+	if account.RoleID == admin.ID {
+		return []uint32{owner.ID, admin.ID}, user.LastRoleAdmin, nil
+	}
+	return nil, "", nil
+}
+
+func (u *DeleteOwnAccountUseCase) hasOtherHolder(exceptUserID uint32, roleIDs []uint32) (bool, error) {
+	everyone, err := u.users.GetAll()
+	if err != nil {
+		return false, err
+	}
+	for _, candidate := range everyone {
+		if candidate.ID != exceptUserID && candidate.IsVerified && slices.Contains(roleIDs, candidate.RoleID) {
+			return true, nil
+		}
+	}
+	return false, nil
+}
+
+func (u *DeleteOwnAccountUseCase) removableAvatar(account user.User) (*image.Image, error) {
+	own, err := u.authors.GetByUserID(account.ID)
+	if errors.Is(err, author.ErrAuthorNotFound) || err == nil && own.AvatarID == nil {
+		return nil, nil
+	}
+	if err != nil {
+		return nil, err
+	}
+	avatar, err := u.images.Get(*own.AvatarID)
+	if errors.Is(err, image.ErrImageNotFound) {
+		return nil, nil
+	}
+	if err != nil {
+		return nil, err
+	}
+	usages, err := u.usage.Usage(avatar.ID)
+	if err != nil {
+		return nil, err
+	}
+	for _, found := range usages {
+		if found.Type != UsageTypeAuthor || found.ID != own.ID {
+			return nil, nil
+		}
+	}
+	return &avatar, nil
+}
+
+func (u *DeleteOwnAccountUseCase) discardAvatar(avatar *image.Image) {
+	if avatar == nil {
+		return
+	}
+	if err := u.avatars.discardFiles(*avatar); err != nil {
+		log.Println("error when deleting the stored avatar of a deleted account:", err)
+	}
+}
+
+func (u *DeleteOwnAccountUseCase) revoke(command DeleteOwnAccountCommand) {
+	if command.SessionID == "" {
+		return
+	}
+	if err := u.sessions.Revoke(command.SessionID, command.SessionExpiresAt); err != nil {
+		log.Println("error when revoking the session of a deleted account:", err)
+	}
+}
+
+func (u *DeleteOwnAccountUseCase) notify(account user.User) {
+	address := account.Email
+	u.dispatcher.Dispatch(func() {
+		if err := u.mailRepository.Send(address, accountDeletedTemplateName, MailAccountDeletedData{Host: u.publicURL}); err != nil {
+			log.Println("error when Send-ing the account deleted mail:", err)
+		}
+	})
+}
+
+func (u *DeleteOwnAccountUseCase) recordSuccess(ctx context.Context, account user.User) {
+	event := audit.NewEvent(audit.ActionUserDeleteAccount, audit.CategoryUsers)
+	id := account.ID
+	event.Actor = audit.Actor{Type: audit.ActorUser, ID: &id, Name: user.DeletedUserName}
+	event.Target = audit.NewTarget(audit.TargetUser, account.ID, user.DeletedUserName)
+	event.Security = true
+	u.recorder.Record(ctx, event)
+}

internal/infrastructure/useCases/ExportUserData.go

@@ -0,0 +1,356 @@
+package useCases
+
+import (
+	"RenewCMS/internal/domain/apikey"
+	"RenewCMS/internal/domain/article"
+	"RenewCMS/internal/domain/audit"
+	"RenewCMS/internal/domain/author"
+	"RenewCMS/internal/domain/contenttype"
+	"RenewCMS/internal/domain/entry"
+	"RenewCMS/internal/domain/image"
+	"RenewCMS/internal/domain/role"
+	"RenewCMS/internal/domain/user"
+	"archive/zip"
+	"bytes"
+	"context"
+	"encoding/json"
+	"errors"
+	"strconv"
+	"strings"
+	"time"
+)
+
+const (
+	exportProfileFile  = "profile.json"
+	exportAuthoredFile = "authored-content.json"
+	exportMediaFile    = "uploaded-media.json"
+	exportActivityFile = "account-activity.json"
+	exportIndent       = "  "
+	exportFilenameDate = "2006-01-02"
+	exportFallbackName = "user"
+)
+
+type ExportUserDataUseCase struct {
+	users        user.Repository
+	roles        role.Repository
+	authors      author.Repository
+	keys         apikey.Repository
+	articles     article.Repository
+	entries      entry.Repository
+	contentTypes contenttype.Repository
+	images       image.Repository
+	events       audit.Repository
+	now          func() time.Time
+	recorder     audit.Recorder
+	slots        chan struct{}
+}
+
+type UserDataArchive struct {
+	Filename string
+	Content  []byte
+}
+
+type exportRole struct {
+	ID   uint32 `json:"id"`
+	Name string `json:"name"`
+}
+
+type exportAPIKey struct {
+	ID         uint32     `json:"id"`
+	Name       string     `json:"name"`
+	Prefix     string     `json:"prefix"`
+	CreatedAt  time.Time  `json:"created_at"`
+	LastUsedAt *time.Time `json:"last_used_at"`
+	RevokedAt  *time.Time `json:"revoked_at"`
+}
+
+type exportProfile struct {
+	ID           uint32         `json:"id"`
+	Username     string         `json:"username"`
+	DisplayName  string         `json:"display_name"`
+	Email        string         `json:"email"`
+	PendingEmail string         `json:"pending_email"`
+	Role         exportRole     `json:"role"`
+	IsVerified   bool           `json:"is_verified"`
+	CreatedAt    time.Time      `json:"created_at"`
+	UpdatedAt    time.Time      `json:"updated_at"`
+	Author       *author.Byline `json:"author"`
+	APIKeys      []exportAPIKey `json:"api_keys"`
+}
+
+type exportArticle struct {
+	ID        uint32         `json:"id"`
+	Title     string         `json:"title"`
+	Body      string         `json:"body"`
+	Slug      string         `json:"slug"`
+	SiteID    uint32         `json:"site_id"`
+	IsOnline  bool           `json:"is_online"`
+	CreatedAt time.Time      `json:"created_at"`
+	UpdatedAt time.Time      `json:"updated_at"`
+	Authors   []exportCredit `json:"authors"`
+}
+
+type exportCredit struct {
+	ID   uint32 `json:"id"`
+	Name string `json:"name"`
+	Slug string `json:"slug"`
+}
+
+type exportEntry struct {
+	ID          uint32         `json:"id"`
+	ContentType string         `json:"content_type"`
+	Data        map[string]any `json:"data"`
+	CreatedAt   time.Time      `json:"created_at"`
+	UpdatedAt   time.Time      `json:"updated_at"`
+}
+
+type exportAuthored struct {
+	Articles []exportArticle `json:"articles"`
+	Entries  []exportEntry   `json:"entries"`
+}
+
+type exportImage struct {
+	ID         uint32    `json:"id"`
+	Filename   string    `json:"filename"`
+	Mime       string    `json:"mime"`
+	Size       int64     `json:"size"`
+	Hash       string    `json:"hash"`
+	UploadedAt time.Time `json:"uploaded_at"`
+}
+
+type exportMedia struct {
+	Images []exportImage `json:"images"`
+}
+
+type exportEvent struct {
+	ID        uint64         `json:"id"`
+	CreatedAt time.Time      `json:"created_at"`
+	Action    string         `json:"action"`
+	Category  audit.Category `json:"category"`
+	Target    audit.Target   `json:"target"`
+	Outcome   audit.Outcome  `json:"outcome"`
+	Security  bool           `json:"security"`
+	Source    audit.Source   `json:"source"`
+	IP        *string        `json:"ip"`
+	UserAgent *string        `json:"user_agent"`
+	Params    map[string]any `json:"params"`
+}
+
+type exportActivity struct {
+	Events []exportEvent `json:"events"`
+}
+
+func NewExportUserDataUseCase(users user.Repository, roles role.Repository, authors author.Repository, keys apikey.Repository, articles article.Repository, entries entry.Repository, contentTypes contenttype.Repository, images image.Repository, events audit.Repository, now func() time.Time, recorder audit.Recorder, maxConcurrent int) *ExportUserDataUseCase {
+	return &ExportUserDataUseCase{users, roles, authors, keys, articles, entries, contentTypes, images, events, now, recorder, make(chan struct{}, max(1, maxConcurrent))}
+}
+
+func (u *ExportUserDataUseCase) Export(ctx context.Context, userID uint32) (UserDataArchive, error) {
+	select {
+	case u.slots <- struct{}{}:
+		defer func() { <-u.slots }()
+	case <-ctx.Done():
+		return UserDataArchive{}, ctx.Err()
+	}
+	account, err := u.users.Get(userID)
+	if err != nil {
+		return UserDataArchive{}, err
+	}
+	profile, linked, err := u.profile(account)
+	if err != nil {
+		return UserDataArchive{}, err
+	}
+	authored, err := u.authored(account, linked)
+	if err != nil {
+		return UserDataArchive{}, err
+	}
+	media, err := u.media(account)
+	if err != nil {
+		return UserDataArchive{}, err
+	}
+	activity, err := u.activity(account, linked)
+	if err != nil {
+		return UserDataArchive{}, err
+	}
+	content, err := zipJSON([]namedDocument{
+		{exportProfileFile, profile},
+		{exportAuthoredFile, authored},
+		{exportMediaFile, media},
+		{exportActivityFile, activity},
+	})
+	if err != nil {
+		return UserDataArchive{}, err
+	}
+
+	event := audit.NewEvent(audit.ActionUserExportData, audit.CategoryUsers)
+	event.Target = userTarget(account)
+	u.recorder.Record(ctx, event)
+	return UserDataArchive{Filename: u.filename(account), Content: content}, nil
+}
+
+func (u *ExportUserDataUseCase) filename(account user.User) string {
+	return "renewcms-export-" + exportUsername(account.Username) + "-" + u.now().UTC().Format(exportFilenameDate) + ".zip"
+}
+
+func exportUsername(username string) string {
+	var reduced strings.Builder
+	for _, char := range strings.ToLower(username) {
+		if char >= 'a' && char <= 'z' || char >= '0' && char <= '9' || char == '-' {
+			reduced.WriteRune(char)
+		} else if !strings.HasSuffix(reduced.String(), "-") {
+			reduced.WriteRune('-')
+		}
+	}
+	name := strings.Trim(reduced.String(), "-")
+	if name == "" {
+		return exportFallbackName
+	}
+	return name
+}
+
+func (u *ExportUserDataUseCase) profile(account user.User) (exportProfile, *author.Author, error) {
+	assigned, err := u.roles.Get(account.RoleID)
+	if err != nil {
+		return exportProfile{}, nil, err
+	}
+	linked, err := u.linkedAuthor(account.ID)
+	if err != nil {
+		return exportProfile{}, nil, err
+	}
+	keys, err := u.keys.ListByUser(account.ID)
+	if err != nil {
+		return exportProfile{}, nil, err
+	}
+	profile := exportProfile{
+		ID: account.ID, Username: account.Username, DisplayName: account.DisplayName, Email: account.Email,
+		PendingEmail: account.PendingEmail, Role: exportRole{ID: assigned.ID, Name: assigned.Name},
+		IsVerified: account.IsVerified, CreatedAt: account.CreatedAt, UpdatedAt: account.UpdatedAt,
+		APIKeys: make([]exportAPIKey, 0, len(keys)),
+	}
+	if linked != nil {
+		byline := linked.Byline()
+		profile.Author = &byline
+	}
+	for _, key := range keys {
+		profile.APIKeys = append(profile.APIKeys, exportAPIKey{ID: key.ID, Name: key.Name, Prefix: key.Prefix, CreatedAt: key.CreatedAt, LastUsedAt: key.LastUsedAt, RevokedAt: key.RevokedAt})
+	}
+	return profile, linked, nil
+}
+
+func (u *ExportUserDataUseCase) linkedAuthor(userID uint32) (*author.Author, error) {
+	linked, err := u.authors.GetByUserID(userID)
+	if errors.Is(err, author.ErrAuthorNotFound) {
+		return nil, nil
+	}
+	if err != nil {
+		return nil, err
+	}
+	return &linked, nil
+}
+
+func (u *ExportUserDataUseCase) authored(account user.User, linked *author.Author) (exportAuthored, error) {
+	var authorID *uint32
+	if linked != nil {
+		authorID = &linked.ID
+	}
+	articles, err := u.articles.ListForAccount(account.ID, authorID)
+	if err != nil {
+		return exportAuthored{}, err
+	}
+	entries, err := u.entries.ListByCreator(account.ID)
+	if err != nil {
+		return exportAuthored{}, err
+	}
+	keys, err := u.contentTypeKeys()
+	if err != nil {
+		return exportAuthored{}, err
+	}
+	authored := exportAuthored{Articles: make([]exportArticle, 0, len(articles)), Entries: make([]exportEntry, 0, len(entries))}
+	for _, item := range articles {
+		credits := make([]exportCredit, 0, len(item.Authors))
+		for _, byline := range item.Authors {
+			credits = append(credits, exportCredit{byline.ID, byline.Name, byline.Slug})
+		}
+		authored.Articles = append(authored.Articles, exportArticle{item.ID, item.Title, item.Body, item.Slug, item.SiteID, item.IsOnline, item.CreatedAt, item.UpdatedAt, credits})
+	}
+	for _, item := range entries {
+		key, known := keys[item.ContentTypeID]
+		if !known {
+			key = strconv.FormatUint(uint64(item.ContentTypeID), 10)
+		}
+		authored.Entries = append(authored.Entries, exportEntry{item.ID, key, item.Data, item.CreatedAt, item.UpdatedAt})
+	}
+	return authored, nil
+}
+
+func (u *ExportUserDataUseCase) contentTypeKeys() (map[uint32]string, error) {
+	types, err := u.contentTypes.List()
+	if err != nil {
+		return nil, err
+	}
+	keys := make(map[uint32]string, len(types))
+	for _, contentType := range types {
+		keys[contentType.ID] = contentType.Key
+	}
+	return keys, nil
+}
+
+func (u *ExportUserDataUseCase) media(account user.User) (exportMedia, error) {
+	images, err := u.images.ListByUploader(account.ID)
+	if err != nil {
+		return exportMedia{}, err
+	}
+	media := exportMedia{Images: make([]exportImage, 0, len(images))}
+	for _, item := range images {
+		media.Images = append(media.Images, exportImage{item.ID, item.Filename, item.ContentType, item.Size, item.SHA256, item.CreatedAt})
+	}
+	return media, nil
+}
+
+func (u *ExportUserDataUseCase) activity(account user.User, linked *author.Author) (exportActivity, error) {
+	id := account.ID
+	var ownAuthorID *uint32
+	if linked != nil {
+		ownAuthorID = &linked.ID
+	}
+	page, err := u.events.List(audit.Filter{Actor: &audit.ActorRef{Type: audit.ActorUser, ID: &id}})
+	if err != nil {
+		return exportActivity{}, err
+	}
+	activity := exportActivity{Events: make([]exportEvent, 0, len(page.Items))}
+	for _, item := range page.Items {
+		if item.ConcernsOtherPerson(account.ID, ownAuthorID) {
+			continue
+		}
+		params := item.Params
+		if params == nil {
+			params = map[string]any{}
+		}
+		activity.Events = append(activity.Events, exportEvent{item.ID, item.CreatedAt, item.Action, item.Category, item.Target, item.Outcome, item.Security, item.Source, item.IP, item.UserAgent, params})
+	}
+	return activity, nil
+}
+
+type namedDocument struct {
+	name  string
+	value any
+}
+
+func zipJSON(documents []namedDocument) ([]byte, error) {
+	var buffer bytes.Buffer
+	archive := zip.NewWriter(&buffer)
+	for _, document := range documents {
+		file, err := archive.Create(document.name)
+		if err != nil {
+			return nil, err
+		}
+		encoder := json.NewEncoder(file)
+		encoder.SetIndent("", exportIndent)
+		if err := encoder.Encode(document.value); err != nil {
+			return nil, err
+		}
+	}
+	if err := archive.Close(); err != nil {
+		return nil, err
+	}
+	return buffer.Bytes(), nil
+}

internal/infrastructure/useCases/RequestEmailChange.go

@@ -0,0 +1,60 @@
+package useCases
+
+import (
+	"RenewCMS/internal/domain/audit"
+	"RenewCMS/internal/domain/hash"
+	"RenewCMS/internal/domain/mail"
+	"RenewCMS/internal/domain/user"
+	"context"
+	"strings"
+	"time"
+)
+
+type RequestEmailChangeUseCase struct {
+	userRepository user.Repository
+	hasher         hash.Hasher
+	issuer         emailChangeIssuer
+	recorder       audit.Recorder
+}
+
+type RequestEmailChangeCommand struct {
+	UserID          uint32
+	NewEmail        string
+	CurrentPassword string
+}
+
+func NewRequestEmailChangeUseCase(userRepository user.Repository, hasher hash.Hasher, mailRepository mail.Repository, dispatcher mail.Dispatcher, publicURL string, now func() time.Time, recorder audit.Recorder) *RequestEmailChangeUseCase {
+	return &RequestEmailChangeUseCase{userRepository, hasher, emailChangeIssuer{userRepository, hasher, mailRepository, dispatcher, publicURL, now}, recorder}
+}
+
+func (u *RequestEmailChangeUseCase) RequestEmailChange(ctx context.Context, command RequestEmailChangeCommand) (string, error) {
+	account, err := u.userRepository.Get(command.UserID)
+	if err != nil {
+		return "", err
+	}
+	event := audit.NewEvent(audit.ActionUserRequestEmail, audit.CategoryUsers)
+	event.Target = userTarget(account)
+	event.Security = true
+
+	if err := u.refuse(account, command); err != nil {
+		recordFailure(ctx, u.recorder, event, err)
+		return "", err
+	}
+	if _, err := u.issuer.issue(account, command.NewEmail); err != nil {
+		recordFailure(ctx, u.recorder, event, err)
+		return "", err
+	}
+	u.issuer.sendNotice(account, command.NewEmail)
+	u.recorder.Record(ctx, event)
+	return command.NewEmail, nil
+}
+
+func (u *RequestEmailChangeUseCase) refuse(account user.User, command RequestEmailChangeCommand) error {
+	if u.hasher.Compare(account.Password, command.CurrentPassword) != nil {
+		return user.ErrWrongPassword
+	}
+	if strings.EqualFold(strings.TrimSpace(command.NewEmail), account.Email) {
+		return user.ErrSameEmail
+	}
+	return nil
+}

internal/infrastructure/useCases/ResendEmailChange.go

@@ -0,0 +1,41 @@
+package useCases
+
+import (
+	"RenewCMS/internal/domain/audit"
+	"RenewCMS/internal/domain/hash"
+	"RenewCMS/internal/domain/mail"
+	"RenewCMS/internal/domain/user"
+	"context"
+	"time"
+)
+
+type ResendEmailChangeUseCase struct {
+	userRepository user.Repository
+	issuer         emailChangeIssuer
+	recorder       audit.Recorder
+}
+
+func NewResendEmailChangeUseCase(userRepository user.Repository, hasher hash.Hasher, mailRepository mail.Repository, dispatcher mail.Dispatcher, publicURL string, now func() time.Time, recorder audit.Recorder) *ResendEmailChangeUseCase {
+	return &ResendEmailChangeUseCase{userRepository, emailChangeIssuer{userRepository, hasher, mailRepository, dispatcher, publicURL, now}, recorder}
+}
+
+func (u *ResendEmailChangeUseCase) ResendEmailChange(ctx context.Context, userId uint32) (string, error) {
+	account, err := u.userRepository.Get(userId)
+	if err != nil {
+		return "", err
+	}
+	event := audit.NewEvent(audit.ActionUserResendEmail, audit.CategoryUsers)
+	event.Target = userTarget(account)
+	event.Security = true
+	if account.PendingEmail == "" {
+		recordFailure(ctx, u.recorder, event, user.ErrNoPendingEmailChange)
+		return "", user.ErrNoPendingEmailChange
+	}
+
+	if _, err := u.issuer.issue(account, account.PendingEmail); err != nil {
+		recordFailure(ctx, u.recorder, event, err)
+		return "", err
+	}
+	u.recorder.Record(ctx, event)
+	return account.PendingEmail, nil
+}

internal/infrastructure/useCases/auditFailures.go

@@ -44,6 +44,14 @@ var failureReasons = []failureReason{
 	{user.ErrVerificationCodeExpired, "The verification code has expired."},
 	{user.ErrInvalidDisplayName, "That display name is too long."},
 	{user.ErrUsernameTaken, "That username is already taken."},
+	{user.ErrWrongPassword, audit.ReasonWrongPassword},
+	{user.ErrLastOwner, "Last Owner."},
+	{user.ErrLastAdmin, "Last administrator."},
+	{user.ErrAccountNotDeletable, "The account can't be deleted right now."},
+	{user.ErrSameEmail, "The new address is already the account's email address."},
+	{user.ErrNoPendingEmailChange, "No email change is pending."},
+	{user.ErrInvalidEmailChangeCode, "The email change link is not valid."},
+	{user.ErrEmailUnavailable, "The new address can't be used for this account."},
 	{user.ErrPasswordTooLong, "The password is longer than 72 bytes."},
 	{invite.ErrEmailHasAccount, "That email already has an account."},
 	{invite.ErrPendingInvite, "An invitation is already pending for that email."},

internal/infrastructure/useCases/emailChangeMail.go

@@ -0,0 +1,81 @@
+package useCases
+
+import (
+	"RenewCMS/internal/domain/hash"
+	"RenewCMS/internal/domain/mail"
+	"RenewCMS/internal/domain/user"
+	"log"
+	"time"
+
+	"github.com/google/uuid"
+)
+
+const (
+	verifyNewEmailTemplateName    = "verify-new-email"
+	emailChangeNoticeTemplateName = "email-change-notice"
+)
+
+type MailVerifyNewEmailData struct {
+	Host             string
+	Username         string
+	VerificationCode string
+}
+
+type MailEmailChangeNoticeData struct {
+	Host     string
+	Username string
+	NewEmail string
+}
+
+type emailChangeIssuer struct {
+	userRepository user.Repository
+	hasher         hash.Hasher
+	mailRepository mail.Repository
+	dispatcher     mail.Dispatcher
+	publicURL      string
+	now            func() time.Time
+}
+
+func (i emailChangeIssuer) issue(account user.User, pendingEmail string) (user.User, error) {
+	rawCode := uuid.NewString()
+	hashedCode, err := i.hasher.Hash(rawCode)
+	if err != nil {
+		return user.User{}, err
+	}
+	updated, err := i.userRepository.SetPendingEmailChange(account.ID, pendingEmail, hashedCode, i.now().Add(user.EmailChangeLifetime))
+	if err != nil {
+		return user.User{}, err
+	}
+	i.dispatcher.Dispatch(func() { i.sendVerification(account, pendingEmail, rawCode) })
+	return updated, nil
+}
+
+func (i emailChangeIssuer) sendVerification(account user.User, pendingEmail string, rawCode string) {
+	taken, err := i.userRepository.IsEmailInUse(pendingEmail, account.ID)
+	if err != nil {
+		log.Println("error when checking whether the new email address is in use:", err)
+		return
+	}
+	if taken {
+		return
+	}
+	if err := i.mailRepository.Send(pendingEmail, verifyNewEmailTemplateName, MailVerifyNewEmailData{
+		Host:             i.publicURL,
+		Username:         account.Username,
+		VerificationCode: rawCode,
+	}); err != nil {
+		log.Println("error when Send-ing the new email verification mail:", err)
+	}
+}
+
+func (i emailChangeIssuer) sendNotice(account user.User, pendingEmail string) {
+	i.dispatcher.Dispatch(func() {
+		if err := i.mailRepository.Send(account.Email, emailChangeNoticeTemplateName, MailEmailChangeNoticeData{
+			Host:     i.publicURL,
+			Username: account.Username,
+			NewEmail: pendingEmail,
+		}); err != nil {
+			log.Println("error when Send-ing the email change notice mail:", err)
+		}
+	})
+}