Set `display_name` and/or `avatar_url` for server notices (#2820)

This should fix #2815 by making sure we actually set the `display_name`
and/or `avatar_url` and create the needed membership event.
To avoid creating a new membership event when starting Dendrite,
`SetAvatarURL` and `SetDisplayName` now return a `Changed` value, which
also makes the regular endpoints idempotent.

14 files changed, 189 insertions, 130 deletions

diff --git a/clientapi/routing/profile.go b/clientapi/routing/profile.go
index 0685c735..c9647eb1 100644
--- a/clientapi/routing/profile.go
+++ b/clientapi/routing/profile.go
@@ -19,6 +19,8 @@ import (
 	"net/http"
 	"time"
 
+	"github.com/matrix-org/gomatrixserverlib"
+
 	appserviceAPI "github.com/matrix-org/dendrite/appservice/api"
 	"github.com/matrix-org/dendrite/clientapi/auth/authtypes"
 	"github.com/matrix-org/dendrite/clientapi/httputil"
@@ -27,7 +29,6 @@ import (
 	"github.com/matrix-org/dendrite/roomserver/api"
 	"github.com/matrix-org/dendrite/setup/config"
 	userapi "github.com/matrix-org/dendrite/userapi/api"
-	"github.com/matrix-org/gomatrixserverlib"
 
 	"github.com/matrix-org/gomatrix"
 	"github.com/matrix-org/util"
@@ -126,20 +127,6 @@ func SetAvatarURL(
 		}
 	}
 
-	res := &userapi.QueryProfileResponse{}
-	err = profileAPI.QueryProfile(req.Context(), &userapi.QueryProfileRequest{
-		UserID: userID,
-	}, res)
-	if err != nil {
-		util.GetLogger(req.Context()).WithError(err).Error("profileAPI.QueryProfile failed")
-		return jsonerror.InternalServerError()
-	}
-	oldProfile := &authtypes.Profile{
-		Localpart:   localpart,
-		DisplayName: res.DisplayName,
-		AvatarURL:   res.AvatarURL,
-	}
-
 	setRes := &userapi.PerformSetAvatarURLResponse{}
 	if err = profileAPI.SetAvatarURL(req.Context(), &userapi.PerformSetAvatarURLRequest{
 		Localpart: localpart,
@@ -148,41 +135,17 @@ func SetAvatarURL(
 		util.GetLogger(req.Context()).WithError(err).Error("profileAPI.SetAvatarURL failed")
 		return jsonerror.InternalServerError()
 	}
-
-	var roomsRes api.QueryRoomsForUserResponse
-	err = rsAPI.QueryRoomsForUser(req.Context(), &api.QueryRoomsForUserRequest{
-		UserID:         device.UserID,
-		WantMembership: "join",
-	}, &roomsRes)
-	if err != nil {
-		util.GetLogger(req.Context()).WithError(err).Error("QueryRoomsForUser failed")
-		return jsonerror.InternalServerError()
-	}
-
-	newProfile := authtypes.Profile{
-		Localpart:   localpart,
-		DisplayName: oldProfile.DisplayName,
-		AvatarURL:   r.AvatarURL,
-	}
-
-	events, err := buildMembershipEvents(
-		req.Context(), roomsRes.RoomIDs, newProfile, userID, cfg, evTime, rsAPI,
-	)
-	switch e := err.(type) {
-	case nil:
-	case gomatrixserverlib.BadJSONError:
+	// No need to build new membership events, since nothing changed
+	if !setRes.Changed {
 		return util.JSONResponse{
-			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON(e.Error()),
+			Code: http.StatusOK,
+			JSON: struct{}{},
 		}
-	default:
-		util.GetLogger(req.Context()).WithError(err).Error("buildMembershipEvents failed")
-		return jsonerror.InternalServerError()
 	}
 
-	if err := api.SendEvents(req.Context(), rsAPI, api.KindNew, events, cfg.Matrix.ServerName, cfg.Matrix.ServerName, nil, true); err != nil {
-		util.GetLogger(req.Context()).WithError(err).Error("SendEvents failed")
-		return jsonerror.InternalServerError()
+	response, err := updateProfile(req.Context(), rsAPI, device, setRes.Profile, userID, cfg, evTime)
+	if err != nil {
+		return response
 	}
 
 	return util.JSONResponse{
@@ -255,47 +218,51 @@ func SetDisplayName(
 		}
 	}
 
-	pRes := &userapi.QueryProfileResponse{}
-	err = profileAPI.QueryProfile(req.Context(), &userapi.QueryProfileRequest{
-		UserID: userID,
-	}, pRes)
-	if err != nil {
-		util.GetLogger(req.Context()).WithError(err).Error("profileAPI.QueryProfile failed")
-		return jsonerror.InternalServerError()
-	}
-	oldProfile := &authtypes.Profile{
-		Localpart:   localpart,
-		DisplayName: pRes.DisplayName,
-		AvatarURL:   pRes.AvatarURL,
-	}
-
+	profileRes := &userapi.PerformUpdateDisplayNameResponse{}
 	err = profileAPI.SetDisplayName(req.Context(), &userapi.PerformUpdateDisplayNameRequest{
 		Localpart:   localpart,
 		DisplayName: r.DisplayName,
-	}, &struct{}{})
+	}, profileRes)
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("profileAPI.SetDisplayName failed")
 		return jsonerror.InternalServerError()
 	}
+	// No need to build new membership events, since nothing changed
+	if !profileRes.Changed {
+		return util.JSONResponse{
+			Code: http.StatusOK,
+			JSON: struct{}{},
+		}
+	}
+
+	response, err := updateProfile(req.Context(), rsAPI, device, profileRes.Profile, userID, cfg, evTime)
+	if err != nil {
+		return response
+	}
+
+	return util.JSONResponse{
+		Code: http.StatusOK,
+		JSON: struct{}{},
+	}
+}
 
+func updateProfile(
+	ctx context.Context, rsAPI api.ClientRoomserverAPI, device *userapi.Device,
+	profile *authtypes.Profile,
+	userID string, cfg *config.ClientAPI, evTime time.Time,
+) (util.JSONResponse, error) {
 	var res api.QueryRoomsForUserResponse
-	err = rsAPI.QueryRoomsForUser(req.Context(), &api.QueryRoomsForUserRequest{
+	err := rsAPI.QueryRoomsForUser(ctx, &api.QueryRoomsForUserRequest{
 		UserID:         device.UserID,
 		WantMembership: "join",
 	}, &res)
 	if err != nil {
-		util.GetLogger(req.Context()).WithError(err).Error("QueryRoomsForUser failed")
-		return jsonerror.InternalServerError()
-	}
-
-	newProfile := authtypes.Profile{
-		Localpart:   localpart,
-		DisplayName: r.DisplayName,
-		AvatarURL:   oldProfile.AvatarURL,
+		util.GetLogger(ctx).WithError(err).Error("QueryRoomsForUser failed")
+		return jsonerror.InternalServerError(), err
 	}
 
 	events, err := buildMembershipEvents(
-		req.Context(), res.RoomIDs, newProfile, userID, cfg, evTime, rsAPI,
+		ctx, res.RoomIDs, *profile, userID, cfg, evTime, rsAPI,
 	)
 	switch e := err.(type) {
 	case nil:
@@ -303,21 +270,17 @@ func SetDisplayName(
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
 			JSON: jsonerror.BadJSON(e.Error()),
-		}
+		}, e
 	default:
-		util.GetLogger(req.Context()).WithError(err).Error("buildMembershipEvents failed")
-		return jsonerror.InternalServerError()
-	}
-
-	if err := api.SendEvents(req.Context(), rsAPI, api.KindNew, events, cfg.Matrix.ServerName, cfg.Matrix.ServerName, nil, true); err != nil {
-		util.GetLogger(req.Context()).WithError(err).Error("SendEvents failed")
-		return jsonerror.InternalServerError()
+		util.GetLogger(ctx).WithError(err).Error("buildMembershipEvents failed")
+		return jsonerror.InternalServerError(), e
 	}
 
-	return util.JSONResponse{
-		Code: http.StatusOK,
-		JSON: struct{}{},
+	if err := api.SendEvents(ctx, rsAPI, api.KindNew, events, cfg.Matrix.ServerName, cfg.Matrix.ServerName, nil, true); err != nil {
+		util.GetLogger(ctx).WithError(err).Error("SendEvents failed")
+		return jsonerror.InternalServerError(), err
 	}
+	return util.JSONResponse{}, nil
 }
 
 // getProfile gets the full profile of a user by querying the database or a
diff --git a/clientapi/routing/routing.go b/clientapi/routing/routing.go
index ec5ca899..4ca8e59c 100644
--- a/clientapi/routing/routing.go
+++ b/clientapi/routing/routing.go
@@ -178,7 +178,7 @@ func Setup(
 	// server notifications
 	if cfg.Matrix.ServerNotices.Enabled {
 		logrus.Info("Enabling server notices at /_synapse/admin/v1/send_server_notice")
-		serverNotificationSender, err := getSenderDevice(context.Background(), userAPI, cfg)
+		serverNotificationSender, err := getSenderDevice(context.Background(), rsAPI, userAPI, cfg)
 		if err != nil {
 			logrus.WithError(err).Fatal("unable to get account for sending sending server notices")
 		}
diff --git a/clientapi/routing/server_notices.go b/clientapi/routing/server_notices.go
index 7729eddd..a6a78061 100644
--- a/clientapi/routing/server_notices.go
+++ b/clientapi/routing/server_notices.go
@@ -277,6 +277,7 @@ func (r sendServerNoticeRequest) valid() (ok bool) {
 // It returns an userapi.Device, which is used for building the event
 func getSenderDevice(
 	ctx context.Context,
+	rsAPI api.ClientRoomserverAPI,
 	userAPI userapi.ClientUserAPI,
 	cfg *config.ClientAPI,
 ) (*userapi.Device, error) {
@@ -291,16 +292,32 @@ func getSenderDevice(
 		return nil, err
 	}
 
-	// set the avatarurl for the user
-	res := &userapi.PerformSetAvatarURLResponse{}
+	// Set the avatarurl for the user
+	avatarRes := &userapi.PerformSetAvatarURLResponse{}
 	if err = userAPI.SetAvatarURL(ctx, &userapi.PerformSetAvatarURLRequest{
 		Localpart: cfg.Matrix.ServerNotices.LocalPart,
 		AvatarURL: cfg.Matrix.ServerNotices.AvatarURL,
-	}, res); err != nil {
+	}, avatarRes); err != nil {
 		util.GetLogger(ctx).WithError(err).Error("userAPI.SetAvatarURL failed")
 		return nil, err
 	}
 
+	profile := avatarRes.Profile
+
+	// Set the displayname for the user
+	displayNameRes := &userapi.PerformUpdateDisplayNameResponse{}
+	if err = userAPI.SetDisplayName(ctx, &userapi.PerformUpdateDisplayNameRequest{
+		Localpart:   cfg.Matrix.ServerNotices.LocalPart,
+		DisplayName: cfg.Matrix.ServerNotices.DisplayName,
+	}, displayNameRes); err != nil {
+		util.GetLogger(ctx).WithError(err).Error("userAPI.SetDisplayName failed")
+		return nil, err
+	}
+
+	if displayNameRes.Changed {
+		profile.DisplayName = cfg.Matrix.ServerNotices.DisplayName
+	}
+
 	// Check if we got existing devices
 	deviceRes := &userapi.QueryDevicesResponse{}
 	err = userAPI.QueryDevices(ctx, &userapi.QueryDevicesRequest{
@@ -310,7 +327,15 @@ func getSenderDevice(
 		return nil, err
 	}
 
+	// We've got an existing account, return the first device of it
 	if len(deviceRes.Devices) > 0 {
+		// If there were changes to the profile, create a new membership event
+		if displayNameRes.Changed || avatarRes.Changed {
+			_, err = updateProfile(ctx, rsAPI, &deviceRes.Devices[0], profile, accRes.Account.UserID, cfg, time.Now())
+			if err != nil {
+				return nil, err
+			}
+		}
 		return &deviceRes.Devices[0], nil
 	}
 
diff --git a/userapi/api/api.go b/userapi/api/api.go
index 66ee9c7c..eef29144 100644
--- a/userapi/api/api.go
+++ b/userapi/api/api.go
@@ -96,7 +96,7 @@ type ClientUserAPI interface {
 	PerformAccountDeactivation(ctx context.Context, req *PerformAccountDeactivationRequest, res *PerformAccountDeactivationResponse) error
 	PerformOpenIDTokenCreation(ctx context.Context, req *PerformOpenIDTokenCreationRequest, res *PerformOpenIDTokenCreationResponse) error
 	SetAvatarURL(ctx context.Context, req *PerformSetAvatarURLRequest, res *PerformSetAvatarURLResponse) error
-	SetDisplayName(ctx context.Context, req *PerformUpdateDisplayNameRequest, res *struct{}) error
+	SetDisplayName(ctx context.Context, req *PerformUpdateDisplayNameRequest, res *PerformUpdateDisplayNameResponse) error
 	QueryNotifications(ctx context.Context, req *QueryNotificationsRequest, res *QueryNotificationsResponse) error
 	InputAccountData(ctx context.Context, req *InputAccountDataRequest, res *InputAccountDataResponse) error
 	PerformKeyBackup(ctx context.Context, req *PerformKeyBackupRequest, res *PerformKeyBackupResponse) error
@@ -579,7 +579,10 @@ type Notification struct {
 type PerformSetAvatarURLRequest struct {
 	Localpart, AvatarURL string
 }
-type PerformSetAvatarURLResponse struct{}
+type PerformSetAvatarURLResponse struct {
+	Profile *authtypes.Profile `json:"profile"`
+	Changed bool               `json:"changed"`
+}
 
 type QueryNumericLocalpartResponse struct {
 	ID int64
@@ -606,6 +609,11 @@ type PerformUpdateDisplayNameRequest struct {
 	Localpart, DisplayName string
 }
 
+type PerformUpdateDisplayNameResponse struct {
+	Profile *authtypes.Profile `json:"profile"`
+	Changed bool               `json:"changed"`
+}
+
 type QueryLocalpartForThreePIDRequest struct {
 	ThreePID, Medium string
 }
diff --git a/userapi/api/api_trace.go b/userapi/api/api_trace.go
index 7e2f6961..90834f7e 100644
--- a/userapi/api/api_trace.go
+++ b/userapi/api/api_trace.go
@@ -168,7 +168,7 @@ func (t *UserInternalAPITrace) QueryAccountAvailability(ctx context.Context, req
 	return err
 }
 
-func (t *UserInternalAPITrace) SetDisplayName(ctx context.Context, req *PerformUpdateDisplayNameRequest, res *struct{}) error {
+func (t *UserInternalAPITrace) SetDisplayName(ctx context.Context, req *PerformUpdateDisplayNameRequest, res *PerformUpdateDisplayNameResponse) error {
 	err := t.Impl.SetDisplayName(ctx, req, res)
 	util.GetLogger(ctx).Infof("SetDisplayName req=%+v res=%+v", js(req), js(res))
 	return err
diff --git a/userapi/internal/api.go b/userapi/internal/api.go
index 2f7795df..63044eed 100644
--- a/userapi/internal/api.go
+++ b/userapi/internal/api.go
@@ -170,7 +170,7 @@ func (a *UserInternalAPI) PerformAccountCreation(ctx context.Context, req *api.P
 		return nil
 	}
 
-	if err = a.DB.SetDisplayName(ctx, req.Localpart, req.Localpart); err != nil {
+	if _, _, err = a.DB.SetDisplayName(ctx, req.Localpart, req.Localpart); err != nil {
 		return err
 	}
 
@@ -813,7 +813,10 @@ func (a *UserInternalAPI) QueryPushRules(ctx context.Context, req *api.QueryPush
 }
 
 func (a *UserInternalAPI) SetAvatarURL(ctx context.Context, req *api.PerformSetAvatarURLRequest, res *api.PerformSetAvatarURLResponse) error {
-	return a.DB.SetAvatarURL(ctx, req.Localpart, req.AvatarURL)
+	profile, changed, err := a.DB.SetAvatarURL(ctx, req.Localpart, req.AvatarURL)
+	res.Profile = profile
+	res.Changed = changed
+	return err
 }
 
 func (a *UserInternalAPI) QueryNumericLocalpart(ctx context.Context, res *api.QueryNumericLocalpartResponse) error {
@@ -847,8 +850,11 @@ func (a *UserInternalAPI) QueryAccountByPassword(ctx context.Context, req *api.Q
 	}
 }
 
-func (a *UserInternalAPI) SetDisplayName(ctx context.Context, req *api.PerformUpdateDisplayNameRequest, _ *struct{}) error {
-	return a.DB.SetDisplayName(ctx, req.Localpart, req.DisplayName)
+func (a *UserInternalAPI) SetDisplayName(ctx context.Context, req *api.PerformUpdateDisplayNameRequest, res *api.PerformUpdateDisplayNameResponse) error {
+	profile, changed, err := a.DB.SetDisplayName(ctx, req.Localpart, req.DisplayName)
+	res.Profile = profile
+	res.Changed = changed
+	return err
 }
 
 func (a *UserInternalAPI) QueryLocalpartForThreePID(ctx context.Context, req *api.QueryLocalpartForThreePIDRequest, res *api.QueryLocalpartForThreePIDResponse) error {
diff --git a/userapi/inthttp/client.go b/userapi/inthttp/client.go
index a375d6ca..aa5d46d9 100644
--- a/userapi/inthttp/client.go
+++ b/userapi/inthttp/client.go
@@ -388,7 +388,7 @@ func (h *httpUserInternalAPI) QueryAccountByPassword(
 func (h *httpUserInternalAPI) SetDisplayName(
 	ctx context.Context,
 	request *api.PerformUpdateDisplayNameRequest,
-	response *struct{},
+	response *api.PerformUpdateDisplayNameResponse,
 ) error {
 	return httputil.CallInternalRPCAPI(
 		"SetDisplayName", h.apiURL+PerformSetDisplayNamePath,
diff --git a/userapi/storage/interface.go b/userapi/storage/interface.go
index 02efe7af..fb12b53a 100644
--- a/userapi/storage/interface.go
+++ b/userapi/storage/interface.go
@@ -29,8 +29,8 @@ import (
 type Profile interface {
 	GetProfileByLocalpart(ctx context.Context, localpart string) (*authtypes.Profile, error)
 	SearchProfiles(ctx context.Context, searchString string, limit int) ([]authtypes.Profile, error)
-	SetAvatarURL(ctx context.Context, localpart string, avatarURL string) error
-	SetDisplayName(ctx context.Context, localpart string, displayName string) error
+	SetAvatarURL(ctx context.Context, localpart string, avatarURL string) (*authtypes.Profile, bool, error)
+	SetDisplayName(ctx context.Context, localpart string, displayName string) (*authtypes.Profile, bool, error)
 }
 
 type Account interface {
diff --git a/userapi/storage/postgres/profile_table.go b/userapi/storage/postgres/profile_table.go
index f686127b..2753b23d 100644
--- a/userapi/storage/postgres/profile_table.go
+++ b/userapi/storage/postgres/profile_table.go
@@ -44,10 +44,18 @@ const selectProfileByLocalpartSQL = "" +
 	"SELECT localpart, display_name, avatar_url FROM userapi_profiles WHERE localpart = $1"
 
 const setAvatarURLSQL = "" +
-	"UPDATE userapi_profiles SET avatar_url = $1 WHERE localpart = $2"
+	"UPDATE userapi_profiles AS new" +
+	" SET avatar_url = $1" +
+	" FROM userapi_profiles AS old" +
+	" WHERE new.localpart = $2" +
+	" RETURNING new.display_name, old.avatar_url <> new.avatar_url"
 
 const setDisplayNameSQL = "" +
-	"UPDATE userapi_profiles SET display_name = $1 WHERE localpart = $2"
+	"UPDATE userapi_profiles AS new" +
+	" SET display_name = $1" +
+	" FROM userapi_profiles AS old" +
+	" WHERE new.localpart = $2" +
+	" RETURNING new.avatar_url, old.display_name <> new.display_name"
 
 const selectProfilesBySearchSQL = "" +
 	"SELECT localpart, display_name, avatar_url FROM userapi_profiles WHERE localpart LIKE $1 OR display_name LIKE $1 LIMIT $2"
@@ -100,16 +108,28 @@ func (s *profilesStatements) SelectProfileByLocalpart(
 
 func (s *profilesStatements) SetAvatarURL(
 	ctx context.Context, txn *sql.Tx, localpart string, avatarURL string,
-) (err error) {
-	_, err = s.setAvatarURLStmt.ExecContext(ctx, avatarURL, localpart)
-	return
+) (*authtypes.Profile, bool, error) {
+	profile := &authtypes.Profile{
+		Localpart: localpart,
+		AvatarURL: avatarURL,
+	}
+	var changed bool
+	stmt := sqlutil.TxStmt(txn, s.setAvatarURLStmt)
+	err := stmt.QueryRowContext(ctx, avatarURL, localpart).Scan(&profile.DisplayName, &changed)
+	return profile, changed, err
 }
 
 func (s *profilesStatements) SetDisplayName(
 	ctx context.Context, txn *sql.Tx, localpart string, displayName string,
-) (err error) {
-	_, err = s.setDisplayNameStmt.ExecContext(ctx, displayName, localpart)
-	return
+) (*authtypes.Profile, bool, error) {
+	profile := &authtypes.Profile{
+		Localpart:   localpart,
+		DisplayName: displayName,
+	}
+	var changed bool
+	stmt := sqlutil.TxStmt(txn, s.setDisplayNameStmt)
+	err := stmt.QueryRowContext(ctx, displayName, localpart).Scan(&profile.AvatarURL, &changed)
+	return profile, changed, err
 }
 
 func (s *profilesStatements) SelectProfilesBySearch(
diff --git a/userapi/storage/shared/storage.go b/userapi/storage/shared/storage.go
index 4e28f7b5..f8b6ad31 100644
--- a/userapi/storage/shared/storage.go
+++ b/userapi/storage/shared/storage.go
@@ -96,20 +96,24 @@ func (d *Database) GetProfileByLocalpart(
 // localpart. Returns an error if something went wrong with the SQL query
 func (d *Database) SetAvatarURL(
 	ctx context.Context, localpart string, avatarURL string,
-) error {
-	return d.Writer.Do(d.DB, nil, func(txn *sql.Tx) error {
-		return d.Profiles.SetAvatarURL(ctx, txn, localpart, avatarURL)
+) (profile *authtypes.Profile, changed bool, err error) {
+	err = d.Writer.Do(d.DB, nil, func(txn *sql.Tx) error {
+		profile, changed, err = d.Profiles.SetAvatarURL(ctx, txn, localpart, avatarURL)
+		return err
 	})
+	return
 }
 
 // SetDisplayName updates the display name of the profile associated with the given
 // localpart. Returns an error if something went wrong with the SQL query
 func (d *Database) SetDisplayName(
 	ctx context.Context, localpart string, displayName string,
-) error {
-	return d.Writer.Do(d.DB, nil, func(txn *sql.Tx) error {
-		return d.Profiles.SetDisplayName(ctx, txn, localpart, displayName)
+) (profile *authtypes.Profile, changed bool, err error) {
+	err = d.Writer.Do(d.DB, nil, func(txn *sql.Tx) error {
+		profile, changed, err = d.Profiles.SetDisplayName(ctx, txn, localpart, displayName)
+		return err
 	})
+	return
 }
 
 // SetPassword sets the account password to the given hash.
diff --git a/userapi/storage/sqlite3/profile_table.go b/userapi/storage/sqlite3/profile_table.go
index 267daf04..b6130a1e 100644
--- a/userapi/storage/sqlite3/profile_table.go
+++ b/userapi/storage/sqlite3/profile_table.go
@@ -44,10 +44,12 @@ const selectProfileByLocalpartSQL = "" +
 	"SELECT localpart, display_name, avatar_url FROM userapi_profiles WHERE localpart = $1"
 
 const setAvatarURLSQL = "" +
-	"UPDATE userapi_profiles SET avatar_url = $1 WHERE localpart = $2"
+	"UPDATE userapi_profiles SET avatar_url = $1 WHERE localpart = $2" +
+	" RETURNING display_name"
 
 const setDisplayNameSQL = "" +
-	"UPDATE userapi_profiles SET display_name = $1 WHERE localpart = $2"
+	"UPDATE userapi_profiles SET display_name = $1 WHERE localpart = $2" +
+	" RETURNING avatar_url"
 
 const selectProfilesBySearchSQL = "" +
 	"SELECT localpart, display_name, avatar_url FROM userapi_profiles WHERE localpart LIKE $1 OR display_name LIKE $1 LIMIT $2"
@@ -102,18 +104,40 @@ func (s *profilesStatements) SelectProfileByLocalpart(
 
 func (s *profilesStatements) SetAvatarURL(
 	ctx context.Context, txn *sql.Tx, localpart string, avatarURL string,
-) (err error) {
+) (*authtypes.Profile, bool, error) {
+	profile := &authtypes.Profile{
+		Localpart: localpart,
+		AvatarURL: avatarURL,
+	}
+	old, err := s.SelectProfileByLocalpart(ctx, localpart)
+	if err != nil {
+		return old, false, err
+	}
+	if old.AvatarURL == avatarURL {
+		return old, false, nil
+	}
 	stmt := sqlutil.TxStmt(txn, s.setAvatarURLStmt)
-	_, err = stmt.ExecContext(ctx, avatarURL, localpart)
-	return
+	err = stmt.QueryRowContext(ctx, avatarURL, localpart).Scan(&profile.DisplayName)
+	return profile, true, err
 }
 
 func (s *profilesStatements) SetDisplayName(
 	ctx context.Context, txn *sql.Tx, localpart string, displayName string,
-) (err error) {
+) (*authtypes.Profile, bool, error) {
+	profile := &authtypes.Profile{
+		Localpart:   localpart,
+		DisplayName: displayName,
+	}
+	old, err := s.SelectProfileByLocalpart(ctx, localpart)
+	if err != nil {
+		return old, false, err
+	}
+	if old.DisplayName == displayName {
+		return old, false, nil
+	}
 	stmt := sqlutil.TxStmt(txn, s.setDisplayNameStmt)
-	_, err = stmt.ExecContext(ctx, displayName, localpart)
-	return
+	err = stmt.QueryRowContext(ctx, displayName, localpart).Scan(&profile.AvatarURL)
+	return profile, true, err
 }
 
 func (s *profilesStatements) SelectProfilesBySearch(
diff --git a/userapi/storage/storage_test.go b/userapi/storage/storage_test.go
index 8e5b32b6..354f085f 100644
--- a/userapi/storage/storage_test.go
+++ b/userapi/storage/storage_test.go
@@ -382,15 +382,23 @@ func Test_Profile(t *testing.T) {
 
 		// set avatar & displayname
 		wantProfile.DisplayName = "Alice"
-		wantProfile.AvatarURL = "mxc://aliceAvatar"
-		err = db.SetDisplayName(ctx, aliceLocalpart, "Alice")
+		gotProfile, changed, err := db.SetDisplayName(ctx, aliceLocalpart, "Alice")
+		assert.Equal(t, wantProfile, gotProfile)
 		assert.NoError(t, err, "unable to set displayname")
-		err = db.SetAvatarURL(ctx, aliceLocalpart, "mxc://aliceAvatar")
+		assert.True(t, changed)
+
+		wantProfile.AvatarURL = "mxc://aliceAvatar"
+		gotProfile, changed, err = db.SetAvatarURL(ctx, aliceLocalpart, "mxc://aliceAvatar")
+		assert.NoError(t, err, "unable to set avatar url")
+		assert.Equal(t, wantProfile, gotProfile)
+		assert.True(t, changed)
+
+		// Setting the same avatar again doesn't change anything
+		wantProfile.AvatarURL = "mxc://aliceAvatar"
+		gotProfile, changed, err = db.SetAvatarURL(ctx, aliceLocalpart, "mxc://aliceAvatar")
 		assert.NoError(t, err, "unable to set avatar url")
-		// verify profile
-		gotProfile, err = db.GetProfileByLocalpart(ctx, aliceLocalpart)
-		assert.NoError(t, err, "unable to get profile by localpart")
 		assert.Equal(t, wantProfile, gotProfile)
+		assert.False(t, changed)
 
 		// search profiles
 		searchRes, err := db.SearchProfiles(ctx, "Alice", 2)
diff --git a/userapi/storage/tables/interface.go b/userapi/storage/tables/interface.go
index cc428799..1b239e44 100644
--- a/userapi/storage/tables/interface.go
+++ b/userapi/storage/tables/interface.go
@@ -84,8 +84,8 @@ type OpenIDTable interface {
 type ProfileTable interface {
 	InsertProfile(ctx context.Context, txn *sql.Tx, localpart string) error
 	SelectProfileByLocalpart(ctx context.Context, localpart string) (*authtypes.Profile, error)
-	SetAvatarURL(ctx context.Context, txn *sql.Tx, localpart string, avatarURL string) (err error)
-	SetDisplayName(ctx context.Context, txn *sql.Tx, localpart string, displayName string) (err error)
+	SetAvatarURL(ctx context.Context, txn *sql.Tx, localpart string, avatarURL string) (*authtypes.Profile, bool, error)
+	SetDisplayName(ctx context.Context, txn *sql.Tx, localpart string, displayName string) (*authtypes.Profile, bool, error)
 	SelectProfilesBySearch(ctx context.Context, searchString string, limit int) ([]authtypes.Profile, error)
 }
 
diff --git a/userapi/userapi_test.go b/userapi/userapi_test.go
index 4417f4dc..aaa93f45 100644
--- a/userapi/userapi_test.go
+++ b/userapi/userapi_test.go
@@ -23,13 +23,14 @@ import (
 	"time"
 
 	"github.com/gorilla/mux"
+	"github.com/matrix-org/gomatrixserverlib"
+	"golang.org/x/crypto/bcrypt"
+
 	"github.com/matrix-org/dendrite/internal/httputil"
 	"github.com/matrix-org/dendrite/test"
 	"github.com/matrix-org/dendrite/test/testrig"
 	"github.com/matrix-org/dendrite/userapi"
 	"github.com/matrix-org/dendrite/userapi/inthttp"
-	"github.com/matrix-org/gomatrixserverlib"
-	"golang.org/x/crypto/bcrypt"
 
 	"github.com/matrix-org/dendrite/setup/config"
 	"github.com/matrix-org/dendrite/userapi/api"
@@ -83,10 +84,10 @@ func TestQueryProfile(t *testing.T) {
 	if err != nil {
 		t.Fatalf("failed to make account: %s", err)
 	}
-	if err := accountDB.SetAvatarURL(context.TODO(), "alice", aliceAvatarURL); err != nil {
+	if _, _, err := accountDB.SetAvatarURL(context.TODO(), "alice", aliceAvatarURL); err != nil {
 		t.Fatalf("failed to set avatar url: %s", err)
 	}
-	if err := accountDB.SetDisplayName(context.TODO(), "alice", aliceDisplayName); err != nil {
+	if _, _, err := accountDB.SetDisplayName(context.TODO(), "alice", aliceDisplayName); err != nil {
 		t.Fatalf("failed to set display name: %s", err)
 	}