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

api/dependecyInjection.go

@@ -98,6 +98,10 @@ type UseCases struct {
 	RequestPasswordResetUseCase     *useCases.RequestPasswordResetUseCase
 	ResetPasswordUseCase            *useCases.ResetPasswordUseCase
 	UpdateUserProfileUseCase        *useCases.UpdateUserProfileUseCase
+	RequestEmailChangeUseCase       *useCases.RequestEmailChangeUseCase
+	ResendEmailChangeUseCase        *useCases.ResendEmailChangeUseCase
+	CancelEmailChangeUseCase        *useCases.CancelEmailChangeUseCase
+	ConfirmEmailChangeUseCase       *useCases.ConfirmEmailChangeUseCase
 	ListUsersUseCase                *useCases.ListUsersUseCase
 	CreateInviteUseCase             *useCases.CreateInviteUseCase
 	CancelInviteUseCase             *useCases.CancelInviteUseCase
@@ -105,6 +109,8 @@ type UseCases struct {
 	ListUsersAndInvitesUseCase      *useCases.ListUsersAndInvitesUseCase
 	ChangeUserRoleUseCase           *useCases.ChangeUserRoleUseCase
 	RemoveUserUseCase               *useCases.RemoveUserUseCase
+	ExportUserDataUseCase           *useCases.ExportUserDataUseCase
+	DeleteOwnAccountUseCase         *useCases.DeleteOwnAccountUseCase
 	TransferOwnershipUseCase        *useCases.TransferOwnershipUseCase
 	GetInviteUseCase                *useCases.GetInviteUseCase
 	AcceptInviteUseCase             *useCases.AcceptInviteUseCase
@@ -174,6 +180,7 @@ type Repositories struct {
 	EntryRepo         domainEntry.Repository
 	AuthorRepo        domainAuthor.Repository
 	UserRepo          domainUser.Repository
+	UserEraser        domainUser.Eraser
 	RoleRepo          domainRole.Repository
 	ImageRepo         domainImage.Repository
 	Transactor        domainTransaction.Transactor
@@ -208,6 +215,8 @@ const (
 	updateHelperFileName = "update-helper.json"
 	updatesDirName       = "updates"
 	backupsDirName       = "backups"
+
+	maxConcurrentDataExports = 2
 )
 
 func imageStorageConfig(settings config.Settings) storage.Config {
@@ -319,6 +328,7 @@ func getRepositories(connection *database.Connection, settings config.Settings)
 		EntryRepo:         persistence.NewEntryRepository(db),
 		AuthorRepo:        persistence.NewAuthorRepository(db),
 		UserRepo:          persistence.NewUserRepository(db),
+		UserEraser:        persistence.NewAccountEraser(db),
 		RoleRepo:          persistence.NewRoleRepository(db),
 		ImageRepo:         persistence.NewImageRepository(db),
 		Transactor:        persistence.NewTransactor(db),
@@ -350,9 +360,12 @@ func getRepositories(connection *database.Connection, settings config.Settings)
 
 func getUseCases(repos *Repositories, imageStorage domainImage.Storage, settings config.Settings) *UseCases {
 	hasher := hashing.NewBcryptHasher()
+	mailDispatcher := mailer.NewAsyncDispatcher()
+	sessionRevocation := useCases.NewSessionRevocationUseCase(repos.SessionRepo, time.Now)
 	renderer := markdown.NewConverter()
 	keyGenerator := hashing.NewSHA256KeyGenerator()
 	recorder := auditing.NewRecorder(repos.AuditRepo, time.Now, log.Default())
+	mediaUsage := useCases.NewGetMediaUsageUseCase(repos.ImageRepo, repos.ArticleRepo, repos.SiteRepo, repos.AuthorRepo, repos.ContentTypeRepo, repos.EntryRepo)
 	mergeMedia := useCases.NewMergeMediaUseCase(repos.ImageRepo, repos.ArticleRepo, imageStorage, repos.VariantFileRepo, recorder, repos.ContentTypeRepo, repos.EntryRepo, repos.Transactor, log.Default())
 
 	runPurge := useCases.NewRunPurgeUseCase(repos.ImageRepo, repos.ArticleRepo, mergeMedia, repos.PurgeSettingsRepo, time.Now, log.Default(), recorder, repos.SiteRepo, repos.AuthorRepo)
@@ -366,7 +379,7 @@ func getUseCases(repos *Repositories, imageStorage domainImage.Storage, settings
 		PurgeScheduler:                  scheduler.NewSystemRunner(purgeScheduler, log.Default()),
 		ActivityCleanupScheduler:        scheduler.NewSystemCleanupRunner(activityCleanup, log.Default()),
 		RetentionScheduler:              scheduler.NewSystemRetentionRunner(useCases.NewEnforceRetentionUseCase(repos.UserRepo, repos.InviteRepo, repos.SessionRepo), log.Default()),
-		Token:                           authtoken.New([]byte(settings.JWTSecret), authtoken.WithRevocationStore(useCases.NewSessionRevocationUseCase(repos.SessionRepo, time.Now))),
+		Token:                           authtoken.New([]byte(settings.JWTSecret), authtoken.WithRevocationStore(sessionRevocation)),
 		CreateArticleUseCase:            useCases.NewCreateArticleUseCase(repos.ArticleRepo, renderer, recorder, repos.SiteRepo, repos.AuthorRepo),
 		GetArticleUseCase:               useCases.NewGetArticleUseCase(repos.ArticleRepo, renderer),
 		ListArticlesUseCase:             useCases.NewListArticlesUseCase(repos.ArticleRepo, renderer, repos.SiteRepo),
@@ -416,6 +429,10 @@ func getUseCases(repos *Repositories, imageStorage domainImage.Storage, settings
 		RequestPasswordResetUseCase:     useCases.NewRequestPasswordResetUseCase(repos.UserRepo, hasher, repos.MailRepo, settings.PublicURL, recorder),
 		ResetPasswordUseCase:            useCases.NewResetPasswordUseCase(repos.UserRepo, hasher, repos.APIKeyRepo, time.Now, recorder),
 		UpdateUserProfileUseCase:        useCases.NewUpdateUserProfileUseCase(repos.UserRepo, recorder),
+		RequestEmailChangeUseCase:       useCases.NewRequestEmailChangeUseCase(repos.UserRepo, hasher, repos.MailRepo, mailDispatcher, settings.PublicURL, time.Now, recorder),
+		ResendEmailChangeUseCase:        useCases.NewResendEmailChangeUseCase(repos.UserRepo, hasher, repos.MailRepo, mailDispatcher, settings.PublicURL, time.Now, recorder),
+		CancelEmailChangeUseCase:        useCases.NewCancelEmailChangeUseCase(repos.UserRepo, recorder),
+		ConfirmEmailChangeUseCase:       useCases.NewConfirmEmailChangeUseCase(repos.UserRepo, hasher, time.Now, recorder),
 		ListUsersUseCase:                useCases.NewListUsersUseCase(repos.UserRepo),
 		CreateInviteUseCase:             useCases.NewCreateInviteUseCase(repos.UserRepo, repos.InviteRepo, repos.RoleRepo, repos.ContentTypeRepo, hasher, repos.MailRepo, settings.PublicURL, recorder),
 		CancelInviteUseCase:             useCases.NewCancelInviteUseCase(repos.InviteRepo, recorder),
@@ -423,6 +440,8 @@ func getUseCases(repos *Repositories, imageStorage domainImage.Storage, settings
 		ListUsersAndInvitesUseCase:      useCases.NewListUsersAndInvitesUseCase(repos.UserRepo, repos.InviteRepo, repos.RoleRepo),
 		ChangeUserRoleUseCase:           useCases.NewChangeUserRoleUseCase(repos.UserRepo, repos.RoleRepo, repos.ContentTypeRepo, recorder),
 		RemoveUserUseCase:               useCases.NewRemoveUserUseCase(repos.UserRepo, repos.RoleRepo, repos.ContentTypeRepo, recorder),
+		ExportUserDataUseCase:           useCases.NewExportUserDataUseCase(repos.UserRepo, repos.RoleRepo, repos.AuthorRepo, repos.APIKeyRepo, repos.ArticleRepo, repos.EntryRepo, repos.ContentTypeRepo, repos.ImageRepo, repos.AuditRepo, time.Now, recorder, maxConcurrentDataExports),
+		DeleteOwnAccountUseCase:         useCases.NewDeleteOwnAccountUseCase(repos.UserRepo, repos.RoleRepo, hasher, repos.UserEraser, sessionRevocation, repos.MailRepo, mailDispatcher, settings.PublicURL, recorder, repos.AuthorRepo, repos.ImageRepo, mediaUsage, imageStorage, repos.VariantFileRepo),
 		TransferOwnershipUseCase:        useCases.NewTransferOwnershipUseCase(repos.UserRepo, repos.RoleRepo, recorder),
 		GetInviteUseCase:                useCases.NewGetInviteUseCase(repos.InviteRepo, hasher),
 		AcceptInviteUseCase:             useCases.NewAcceptInviteUseCase(repos.UserRepo, repos.InviteRepo, repos.RoleRepo, hasher, recorder),
@@ -433,7 +452,7 @@ func getUseCases(repos *Repositories, imageStorage domainImage.Storage, settings
 		RenameMediaUseCase:              useCases.NewRenameMediaUseCase(repos.ImageRepo, recorder),
 		DeleteMediaUseCase:              useCases.NewDeleteMediaUseCase(repos.ImageRepo, imageStorage, repos.VariantFileRepo, recorder, repos.SiteRepo, repos.AuthorRepo, repos.ArticleRepo),
 		MergeMediaUseCase:               mergeMedia,
-		GetMediaUsageUseCase:            useCases.NewGetMediaUsageUseCase(repos.ImageRepo, repos.ArticleRepo, repos.SiteRepo, repos.AuthorRepo, repos.ContentTypeRepo, repos.EntryRepo),
+		GetMediaUsageUseCase:            mediaUsage,
 		GetPurgeSettingsUseCase:         useCases.NewGetPurgeSettingsUseCase(repos.PurgeSettingsRepo),
 		UpdatePurgeSettingsUseCase:      useCases.NewUpdatePurgeSettingsUseCase(repos.PurgeSettingsRepo, time.Now),
 		PreviewPurgeUseCase:             useCases.NewPreviewPurgeUseCase(repos.ImageRepo, repos.ArticleRepo, repos.SiteRepo, repos.AuthorRepo, repos.ContentTypeRepo, repos.EntryRepo),

api/handlers/auth/emailChangeHandler.go

@@ -0,0 +1,151 @@
+package auth
+
+import (
+	"RenewCMS/api/pkg/apperr"
+	"RenewCMS/api/pkg/claims"
+	validator "RenewCMS/api/pkg/validator"
+	"RenewCMS/internal/domain/user"
+	"RenewCMS/internal/infrastructure/useCases"
+	"encoding/json"
+	"errors"
+	"net/http"
+)
+
+type EmailChangeHandler struct {
+	RequestUseCase *useCases.RequestEmailChangeUseCase
+	ResendUseCase  *useCases.ResendEmailChangeUseCase
+	CancelUseCase  *useCases.CancelEmailChangeUseCase
+	ConfirmUseCase *useCases.ConfirmEmailChangeUseCase
+}
+
+type RequestEmailChangeCredentials struct {
+	NewEmail        string `json:"new_email" validate:"required,max=255,inviteemail"`
+	CurrentPassword string `json:"current_password" validate:"required"`
+}
+
+type ConfirmEmailChangeCredentials struct {
+	Code string `json:"code" validate:"required"`
+}
+
+func NewEmailChangeHandler(request *useCases.RequestEmailChangeUseCase, resend *useCases.ResendEmailChangeUseCase, cancel *useCases.CancelEmailChangeUseCase, confirm *useCases.ConfirmEmailChangeUseCase) *EmailChangeHandler {
+	return &EmailChangeHandler{
+		RequestUseCase: request,
+		ResendUseCase:  resend,
+		CancelUseCase:  cancel,
+		ConfirmUseCase: confirm,
+	}
+}
+
+func (h *EmailChangeHandler) Request(w http.ResponseWriter, r *http.Request) {
+	var credentials RequestEmailChangeCredentials
+	if err := json.NewDecoder(r.Body).Decode(&credentials); err != nil {
+		http.Error(w, apperr.BodyErrorMessage, http.StatusBadRequest)
+		return
+	}
+	if err := validator.Validate.Struct(credentials); err != nil {
+		http.Error(w, err.Error(), http.StatusBadRequest)
+		return
+	}
+	userId, ok := claims.UserId(r)
+	if !ok {
+		http.Error(w, apperr.UnauthorizedErrorMessage, http.StatusUnauthorized)
+		return
+	}
+
+	pending, err := h.RequestUseCase.RequestEmailChange(r.Context(), useCases.RequestEmailChangeCommand{
+		UserID:          userId,
+		NewEmail:        credentials.NewEmail,
+		CurrentPassword: credentials.CurrentPassword,
+	})
+	if err != nil {
+		writeEmailChangeError(w, err)
+		return
+	}
+	writePendingEmail(w, pending)
+}
+
+func (h *EmailChangeHandler) Resend(w http.ResponseWriter, r *http.Request) {
+	userId, ok := claims.UserId(r)
+	if !ok {
+		http.Error(w, apperr.UnauthorizedErrorMessage, http.StatusUnauthorized)
+		return
+	}
+
+	pending, err := h.ResendUseCase.ResendEmailChange(r.Context(), userId)
+	if err != nil {
+		writeEmailChangeError(w, err)
+		return
+	}
+	writePendingEmail(w, pending)
+}
+
+func (h *EmailChangeHandler) Cancel(w http.ResponseWriter, r *http.Request) {
+	userId, ok := claims.UserId(r)
+	if !ok {
+		http.Error(w, apperr.UnauthorizedErrorMessage, http.StatusUnauthorized)
+		return
+	}
+
+	if err := h.CancelUseCase.CancelEmailChange(r.Context(), userId); err != nil {
+		writeEmailChangeError(w, err)
+		return
+	}
+	w.WriteHeader(http.StatusNoContent)
+}
+
+func (h *EmailChangeHandler) Confirm(w http.ResponseWriter, r *http.Request) {
+	var credentials ConfirmEmailChangeCredentials
+	if err := json.NewDecoder(r.Body).Decode(&credentials); err != nil {
+		http.Error(w, apperr.BodyErrorMessage, http.StatusBadRequest)
+		return
+	}
+	if err := validator.Validate.Struct(credentials); err != nil {
+		http.Error(w, err.Error(), http.StatusBadRequest)
+		return
+	}
+	userId, ok := claims.UserId(r)
+	if !ok {
+		http.Error(w, apperr.UnauthorizedErrorMessage, http.StatusUnauthorized)
+		return
+	}
+
+	email, err := h.ConfirmUseCase.ConfirmEmailChange(r.Context(), userId, credentials.Code)
+	if err != nil {
+		writeEmailChangeError(w, err)
+		return
+	}
+	body, err := json.Marshal(map[string]string{"email": email})
+	if err != nil {
+		http.Error(w, "Internal server error", http.StatusInternalServerError)
+		return
+	}
+	_, _ = w.Write(body)
+}
+
+func writePendingEmail(w http.ResponseWriter, pending string) {
+	body, err := json.Marshal(map[string]string{"pending_email": pending})
+	if err != nil {
+		http.Error(w, "Internal server error", http.StatusInternalServerError)
+		return
+	}
+	_, _ = w.Write(body)
+}
+
+func writeEmailChangeError(w http.ResponseWriter, err error) {
+	switch {
+	case errors.Is(err, user.ErrUserNotFound):
+		http.Error(w, apperr.UnauthorizedErrorMessage, http.StatusUnauthorized)
+	case errors.Is(err, user.ErrWrongPassword):
+		http.Error(w, apperr.WrongPasswordErrorCode, http.StatusForbidden)
+	case errors.Is(err, user.ErrSameEmail):
+		http.Error(w, apperr.SameEmailErrorCode, http.StatusBadRequest)
+	case errors.Is(err, user.ErrNoPendingEmailChange):
+		http.Error(w, apperr.NoPendingEmailChangeErrorCode, http.StatusNotFound)
+	case errors.Is(err, user.ErrInvalidEmailChangeCode):
+		http.Error(w, apperr.InvalidEmailChangeCodeErrorCode, http.StatusForbidden)
+	case errors.Is(err, user.ErrEmailUnavailable):
+		http.Error(w, apperr.EmailUnavailableErrorCode, http.StatusConflict)
+	default:
+		http.Error(w, "Internal server error", http.StatusInternalServerError)
+	}
+}

api/handlers/auth/loginHandler.go

@@ -40,16 +40,7 @@ func NewLoginHandler(token *authtoken.Auth, create *useCases.CreateUserUseCase,
 }
 
 func removeJwtCookie(w http.ResponseWriter, isProduction bool) {
-	http.SetCookie(w, &http.Cookie{
-		Name:     authtoken.CookieName,
-		Value:    "",
-		Expires:  time.Now(),
-		MaxAge:   -1,
-		Secure:   isProduction,
-		HttpOnly: true,
-		SameSite: http.SameSiteLaxMode,
-		Path:     "/",
-	})
+	http.SetCookie(w, authtoken.ExpiredCookie(isProduction))
 }
 
 func setJwtCookie(w http.ResponseWriter, token *authtoken.Auth, isProduction bool, u user.User) error {

api/handlers/auth/meHandler.go

@@ -41,8 +41,9 @@ type meAccess struct {
 
 type meResponse struct {
 	publicuser.PublicUser
-	Author *meAuthor `json:"author"`
-	Access meAccess  `json:"access"`
+	PendingEmail *string   `json:"pending_email"`
+	Author       *meAuthor `json:"author"`
+	Access       meAccess  `json:"access"`
 }
 
 func toMeAccess(access useCases.Access) meAccess {
@@ -60,6 +61,13 @@ func toMeAuthor(found *author.Author) *meAuthor {
 	return &meAuthor{Byline: found.Byline(), ArticleCount: found.ArticleCount}
 }
 
+func pendingEmailOf(account user.User) *string {
+	if account.PendingEmail == "" {
+		return nil
+	}
+	return &account.PendingEmail
+}
+
 func (h *MeHandler) Me(w http.ResponseWriter, r *http.Request) {
 	userId, ok := claims.UserId(r)
 	if !ok {
@@ -89,7 +97,7 @@ func (h *MeHandler) Me(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	body, err := json.Marshal(meResponse{PublicUser: publicuser.New(loadedUser), Author: toMeAuthor(linked), Access: toMeAccess(access)})
+	body, err := json.Marshal(meResponse{PublicUser: publicuser.New(loadedUser), PendingEmail: pendingEmailOf(loadedUser), Author: toMeAuthor(linked), Access: toMeAccess(access)})
 	if err != nil {
 		http.Error(w, "Internal server error", http.StatusInternalServerError)
 		return

api/handlers/user/deleteAccountHandler.go

@@ -0,0 +1,81 @@
+package user
+
+import (
+	"RenewCMS/api/pkg/apperr"
+	"RenewCMS/api/pkg/authtoken"
+	"RenewCMS/api/pkg/claims"
+	validator "RenewCMS/api/pkg/validator"
+	domain "RenewCMS/internal/domain/user"
+	"RenewCMS/internal/infrastructure/useCases"
+	"encoding/json"
+	"errors"
+	"net/http"
+	"time"
+)
+
+type DeleteAccountHandler struct {
+	DeleteUseCase *useCases.DeleteOwnAccountUseCase
+	IsProduction  bool
+}
+
+type DeleteAccountRequest struct {
+	CurrentPassword string `json:"current_password" validate:"required"`
+	Confirmation    string `json:"confirmation" validate:"required,eq=DELETE"`
+}
+
+func NewDeleteAccountHandler(deleteAccount *useCases.DeleteOwnAccountUseCase, isProduction bool) *DeleteAccountHandler {
+	return &DeleteAccountHandler{DeleteUseCase: deleteAccount, IsProduction: isProduction}
+}
+
+func (h *DeleteAccountHandler) Delete(w http.ResponseWriter, r *http.Request) {
+	var request DeleteAccountRequest
+	if err := json.NewDecoder(r.Body).Decode(&request); err != nil {
+		http.Error(w, apperr.BodyErrorMessage, http.StatusBadRequest)
+		return
+	}
+	if err := validator.Validate.Struct(request); err != nil {
+		http.Error(w, err.Error(), http.StatusBadRequest)
+		return
+	}
+	userId, ok := claims.UserId(r)
+	if !ok {
+		http.Error(w, apperr.UnauthorizedErrorMessage, http.StatusUnauthorized)
+		return
+	}
+
+	command := useCases.DeleteOwnAccountCommand{UserID: userId, CurrentPassword: request.CurrentPassword}
+	command.SessionID, command.SessionExpiresAt = sessionOf(r)
+	if err := h.DeleteUseCase.Delete(r.Context(), command); err != nil {
+		writeDeleteAccountError(w, err)
+		return
+	}
+	http.SetCookie(w, authtoken.ExpiredCookie(h.IsProduction))
+	w.WriteHeader(http.StatusNoContent)
+}
+
+func sessionOf(r *http.Request) (string, time.Time) {
+	tokenClaims, err := authtoken.FromContext(r.Context())
+	if err != nil {
+		return "", time.Time{}
+	}
+	id, _ := tokenClaims["jti"].(string)
+	expiry, _ := tokenClaims["exp"].(float64)
+	return id, time.Unix(int64(expiry), 0)
+}
+
+func writeDeleteAccountError(w http.ResponseWriter, err error) {
+	var lastAdmin domain.LastAdminError
+	switch {
+	case errors.Is(err, domain.ErrUserNotFound):
+		http.Error(w, apperr.UnauthorizedErrorMessage, http.StatusUnauthorized)
+	case errors.Is(err, domain.ErrWrongPassword):
+		http.Error(w, apperr.WrongPasswordErrorCode, http.StatusForbidden)
+	case errors.As(err, &lastAdmin):
+		w.Header().Set(apperr.LastRoleHeader, lastAdmin.Role)
+		http.Error(w, apperr.LastAdminErrorCode, http.StatusConflict)
+	case errors.Is(err, domain.ErrAccountNotDeletable):
+		http.Error(w, apperr.AccountNotDeletableErrorCode, http.StatusConflict)
+	default:
+		http.Error(w, "Internal server error", http.StatusInternalServerError)
+	}
+}

api/handlers/user/exportHandler.go

@@ -0,0 +1,44 @@
+package user
+
+import (
+	"RenewCMS/api/pkg/apperr"
+	"RenewCMS/api/pkg/claims"
+	"RenewCMS/internal/infrastructure/useCases"
+	"context"
+	"errors"
+	"net/http"
+	"strconv"
+)
+
+type ExportHandler struct {
+	ExportUseCase *useCases.ExportUserDataUseCase
+}
+
+func NewExportHandler(export *useCases.ExportUserDataUseCase) *ExportHandler {
+	return &ExportHandler{ExportUseCase: export}
+}
+
+func (h *ExportHandler) Export(w http.ResponseWriter, r *http.Request) {
+	userId, ok := claims.UserId(r)
+	if !ok {
+		http.Error(w, apperr.UnauthorizedErrorMessage, http.StatusUnauthorized)
+		return
+	}
+
+	archive, err := h.ExportUseCase.Export(r.Context(), userId)
+	if errors.Is(err, context.Canceled) || errors.Is(err, context.DeadlineExceeded) {
+		http.Error(w, "Service unavailable", http.StatusServiceUnavailable)
+		return
+	}
+	if err != nil {
+		http.Error(w, "Internal server error", http.StatusInternalServerError)
+		return
+	}
+
+	w.Header().Set("Content-Type", "application/zip")
+	w.Header().Set("Cache-Control", "no-store")
+	w.Header().Set("Content-Disposition", "attachment; filename=\""+archive.Filename+"\"")
+	w.Header().Set("Content-Length", strconv.Itoa(len(archive.Content)))
+	w.WriteHeader(http.StatusOK)
+	_, _ = w.Write(archive.Content)
+}

api/middleware/successRateLimit.go

@@ -0,0 +1,90 @@
+package middleware
+
+import (
+	"RenewCMS/api/pkg/apperr"
+	"net/http"
+	"strconv"
+	"sync"
+	"time"
+)
+
+type successSlots struct {
+	mu     sync.Mutex
+	window time.Duration
+	now    func() time.Time
+	taken  map[string]time.Time
+}
+
+func NewUserSuccessLimiter(window time.Duration) func(http.Handler) http.Handler {
+	return NewUserSuccessLimiterAt(window, time.Now)
+}
+
+func NewUserSuccessLimiterAt(window time.Duration, now func() time.Time) func(http.Handler) http.Handler {
+	slots := &successSlots{window: window, now: now, taken: make(map[string]time.Time)}
+
+	return func(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			key := userRateLimitKey(r)
+			claimed, retryAfter, granted := slots.claim(key)
+			if !granted {
+				w.Header().Set("Retry-After", strconv.Itoa(retryAfter))
+				http.Error(w, apperr.TooManyRequestsErrorMessage, http.StatusTooManyRequests)
+				return
+			}
+
+			recorder := &statusRecorder{ResponseWriter: w, status: http.StatusOK}
+			succeeded := false
+			defer func() {
+				if !succeeded {
+					slots.release(key, claimed)
+				}
+			}()
+			next.ServeHTTP(recorder, r)
+			succeeded = recorder.status < http.StatusBadRequest
+		})
+	}
+}
+
+func (s *successSlots) claim(key string) (time.Time, int, bool) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	now := s.now()
+	s.sweepExpired(now)
+	if claimedAt, held := s.taken[key]; held {
+		return time.Time{}, retryAfterSeconds(s.window - now.Sub(claimedAt)), false
+	}
+	s.taken[key] = now
+	return now, 0, true
+}
+
+func (s *successSlots) release(key string, claimedAt time.Time) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	if current, held := s.taken[key]; held && current.Equal(claimedAt) {
+		delete(s.taken, key)
+	}
+}
+
+func (s *successSlots) sweepExpired(now time.Time) {
+	for key, claimedAt := range s.taken {
+		if now.Sub(claimedAt) >= s.window {
+			delete(s.taken, key)
+		}
+	}
+}
+
+type statusRecorder struct {
+	http.ResponseWriter
+	status int
+}
+
+func (s *statusRecorder) WriteHeader(status int) {
+	s.status = status
+	s.ResponseWriter.WriteHeader(status)
+}
+
+func (s *statusRecorder) Unwrap() http.ResponseWriter {
+	return s.ResponseWriter
+}

api/pkg/apperr/messages.go

@@ -127,3 +127,12 @@ const InvalidRoleErrorMessage = "invalid_role"
 const UserRoleChangedErrorMessage = "user_role_changed"
 const InvalidTransferErrorMessage = "invalid_transfer"
 const ConfirmationMismatchErrorMessage = "confirmation_mismatch"
+const WrongPasswordErrorCode = "wrong_password"
+const SameEmailErrorCode = "same_email"
+const NoPendingEmailChangeErrorCode = "no_pending_email_change"
+const InvalidEmailChangeCodeErrorCode = "invalid_email_change_code"
+const EmailUnavailableErrorCode = "email_unavailable"
+
+const LastAdminErrorCode = "last_admin"
+const AccountNotDeletableErrorCode = "account_not_deletable"
+const LastRoleHeader = "X-Last-Role"

api/pkg/authtoken/cookie.go

@@ -0,0 +1,19 @@
+package authtoken
+
+import (
+	"net/http"
+	"time"
+)
+
+func ExpiredCookie(secure bool) *http.Cookie {
+	return &http.Cookie{
+		Name:     CookieName,
+		Value:    "",
+		Expires:  time.Now(),
+		MaxAge:   -1,
+		Secure:   secure,
+		HttpOnly: true,
+		SameSite: http.SameSiteLaxMode,
+		Path:     "/",
+	}
+}

api/router.go

@@ -52,6 +52,14 @@ func GetHelloWorld(w http.ResponseWriter, _ *http.Request) {
 const (
 	apiKeyMaxRequests = 120
 	apiKeyWindow      = time.Minute
+
+	emailChangeMaxRequests = 5
+	emailChangeWindow      = 15 * time.Minute
+
+	dataExportWindow = 15 * time.Minute
+
+	accountDeleteMaxRequests = 5
+	accountDeleteWindow      = 15 * time.Minute
 )
 
 func (c *UseCases) apiKeyAuth() func(http.Handler) http.Handler {
@@ -119,6 +127,7 @@ func NewAuthRouter(container *UseCases, isProduction bool, rateLimit config.Auth
 	verificationHandler := auth.NewVerificationHandler(container.VerifyUserUseCase, container.CancelRegistrationUseCase, isProduction)
 	meHandler := auth.NewMeHandler(container.GetUserUseCase, container.GetMyAuthorUseCase, container.GetMyAccessUseCase)
 	passwordResetHandler := auth.NewPasswordResetHandler(container.RequestPasswordResetUseCase, container.ResetPasswordUseCase)
+	emailChangeHandler := auth.NewEmailChangeHandler(container.RequestEmailChangeUseCase, container.ResendEmailChangeUseCase, container.CancelEmailChangeUseCase, container.ConfirmEmailChangeUseCase)
 	acceptInviteHandler := auth.NewAcceptInviteHandler(container.GetInviteUseCase, container.AcceptInviteUseCase, container.Token, isProduction)
 
 	r.Post("/register", loginHandler.Register)
@@ -149,6 +158,22 @@ func NewAuthRouter(container *UseCases, isProduction bool, rateLimit config.Auth
 		r.Post("/verify", verificationHandler.Verify)
 		r.Delete("/register", verificationHandler.CancelRegistration)
 	})
+	r.Group(func(r chi.Router) {
+		r.Use(middleware.RequireSession)
+		r.Use(authtoken.Verifier(container.Token))
+		r.Use(middleware.AuditContext(container.GetUserUseCase, trustedProxies))
+		r.Use(middleware.RequireSignedIn)
+		r.Use(authtoken.Authenticator)
+		r.Use(middleware.RequireCurrentToken(container.GetUserUseCase))
+		r.Use(middleware.RequireVerifiedUser(container.GetUserUseCase))
+		r.Delete("/email/change", emailChangeHandler.Cancel)
+		r.Post("/email/confirm", emailChangeHandler.Confirm)
+		r.Group(func(r chi.Router) {
+			r.Use(middleware.NewUserRateLimiter(emailChangeMaxRequests, emailChangeWindow))
+			r.Post("/email/change", emailChangeHandler.Request)
+			r.Post("/email/resend", emailChangeHandler.Resend)
+		})
+	})
 	r.Group(func(r chi.Router) {
 		r.Use(authtoken.Verifier(container.Token))
 		r.Use(container.apiKeyAuth())
@@ -159,7 +184,7 @@ func NewAuthRouter(container *UseCases, isProduction bool, rateLimit config.Auth
 	return r
 }
 
-func NewUserRouter(container *UseCases, rateLimit config.AuthRateLimitSettings, trustedProxies []string) http.Handler {
+func NewUserRouter(container *UseCases, isProduction bool, rateLimit config.AuthRateLimitSettings, trustedProxies []string) http.Handler {
 	r := chi.NewRouter()
 
 	userHandler := user.NewHandler(container.UpdateUserProfileUseCase)
@@ -167,6 +192,8 @@ func NewUserRouter(container *UseCases, rateLimit config.AuthRateLimitSettings,
 	inviteHandler := user.NewInviteHandler(container.CreateInviteUseCase, container.CancelInviteUseCase, container.RenewInviteUseCase, container.ListUsersAndInvitesUseCase)
 	roleHandler := user.NewRoleHandler(container.ChangeUserRoleUseCase)
 	removeHandler := user.NewRemoveHandler(container.RemoveUserUseCase)
+	exportHandler := user.NewExportHandler(container.ExportUserDataUseCase)
+	deleteAccountHandler := user.NewDeleteAccountHandler(container.DeleteOwnAccountUseCase, isProduction)
 
 	r.Group(func(r chi.Router) {
 		r.Use(authtoken.Verifier(container.Token))
@@ -187,6 +214,27 @@ func NewUserRouter(container *UseCases, rateLimit config.AuthRateLimitSettings,
 			r.Post("/invite/{id}/renew", inviteHandler.RenewInvite)
 		})
 	})
+	r.Group(func(r chi.Router) {
+		r.Use(middleware.RequireSession)
+		r.Use(authtoken.Verifier(container.Token))
+		r.Use(middleware.AuditContext(container.GetUserUseCase, trustedProxies))
+		r.Use(middleware.RequireSignedIn)
+		r.Use(authtoken.Authenticator)
+		r.Use(middleware.RequireCurrentToken(container.GetUserUseCase))
+		r.Use(middleware.RequireVerifiedUser(container.GetUserUseCase))
+		r.With(middleware.NewUserSuccessLimiter(dataExportWindow)).Get("/me/export", exportHandler.Export)
+	})
+	r.Group(func(r chi.Router) {
+		r.Use(middleware.RequireSession)
+		r.Use(authtoken.Verifier(container.Token))
+		r.Use(middleware.AuditContext(container.GetUserUseCase, trustedProxies))
+		r.Use(middleware.RequireSignedIn)
+		r.Use(authtoken.Authenticator)
+		r.Use(middleware.RequireCurrentToken(container.GetUserUseCase))
+		r.Use(middleware.RequireVerifiedUser(container.GetUserUseCase))
+		r.Use(middleware.NewUserRateLimiter(accountDeleteMaxRequests, accountDeleteWindow))
+		r.Delete("/me", deleteAccountHandler.Delete)
+	})
 	r.Group(func(r chi.Router) {
 		r.Use(middleware.RequireSession)
 		r.Use(authtoken.Verifier(container.Token))
@@ -535,7 +583,7 @@ func InitBackendRoutes(container *UseCases, settings config.Settings) *chi.Mux {
 		r.Use(authtoken.Verifier(container.Token))
 		r.Mount("/article", NewArticleRouter(container, settings.TrustedProxies))
 	})
-	r.Mount("/user", NewUserRouter(container, settings.AuthRateLimit, settings.TrustedProxies))
+	r.Mount("/user", NewUserRouter(container, settings.IsProduction(), settings.AuthRateLimit, settings.TrustedProxies))
 	r.Mount("/settings", NewSettingsRouter(container, settings.TrustedProxies))
 	r.Mount("/site", NewSiteRouter(container, settings.TrustedProxies))
 	r.Mount("/role", NewRoleRouter(container, settings.TrustedProxies))