Add simple thread support for forums

.github/workflows/go.yml

@@ -8,8 +8,8 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        go-version: ["1.24", "1.25"]
-    name: Lint ${{ matrix.go-version == '1.25' && '(latest)' || '(old)' }}
+        go-version: ["1.25", "1.26"]
+    name: Lint ${{ matrix.go-version == '1.26' && '(latest)' || '(old)' }}
 
     steps:
       - uses: actions/checkout@v4

CHANGELOG.md

@@ -1,3 +1,15 @@
+# v0.7.6 (2026-02-16)
+
+* Bumped minimum Go version to 1.25.
+* Updated Docker image to Alpine 3.23.
+* Added support for following tombstones.
+* Added support for disabling link previews in messages sent to Discord using
+  [MSC4095].
+* Added support for federation thumbnail endpoint when using direct media.
+* Disabled using `restricted` join rules by default.
+
+[MSC4095]: https://github.com/matrix-org/matrix-spec-proposals/pull/4095
+
 # v0.7.5 (2025-07-16)
 
 * Fixed federation key response when using direct media.

Dockerfile

@@ -1,4 +1,4 @@
-FROM golang:1-alpine3.22 AS builder
+FROM golang:1-alpine3.23 AS builder
 
 RUN apk add --no-cache git ca-certificates build-base su-exec olm-dev
 
@@ -6,7 +6,7 @@ COPY . /build
 WORKDIR /build
 RUN go build -o /usr/bin/mautrix-discord
 
-FROM alpine:3.22
+FROM alpine:3.23
 
 ENV UID=1337 \
     GID=1337
@@ -17,5 +17,6 @@ COPY --from=builder /usr/bin/mautrix-discord /usr/bin/mautrix-discord
 COPY --from=builder /build/example-config.yaml /opt/mautrix-discord/example-config.yaml
 COPY --from=builder /build/docker-run.sh /docker-run.sh
 VOLUME /data
+WORKDIR /data
 
 CMD ["/docker-run.sh"]

Dockerfile.ci

@@ -1,4 +1,4 @@
-FROM alpine:3.22
+FROM alpine:3.23
 
 ENV UID=1337 \
     GID=1337
@@ -10,5 +10,6 @@ COPY $EXECUTABLE /usr/bin/mautrix-discord
 COPY ./example-config.yaml /opt/mautrix-discord/example-config.yaml
 COPY ./docker-run.sh /docker-run.sh
 VOLUME /data
+WORKDIR /data
 
 CMD ["/docker-run.sh"]

commands.go

@@ -706,9 +706,25 @@ func fnBridge(ce *WrappedCommandEvent) {
 	}
 	portal := ce.User.GetExistingPortalByID(channelID)
 	if portal == nil {
+		// HACK: Before giving up, discover if the user is trying to join a
+		// thread. Then, cause the creation of a portal.
+		// This is for forum channel threads; they don't show up on the
+		// forum channels.
+		ch, err := ce.User.Session.Channel(channelID)
+		if err != nil {
 			ce.Reply("Channel not found")
 			return
 		}
+
+		if ch.Type != discordgo.ChannelTypeGuildPublicThread &&
+			ch.Type != discordgo.ChannelTypeGuildPrivateThread {
+			return
+		}
+
+		ce.ZLog.Debug().Msg("Adding public / private thread as a portal")
+		portal = ce.User.GetPortalByID(channelID, ch.Type)
+
+	}
 	portal.roomCreateLock.Lock()
 	defer portal.roomCreateLock.Unlock()
 	if portal.MXID != "" {

database/json.go

@@ -0,0 +1,20 @@
+package database
+
+import (
+	"go.mau.fi/util/dbutil"
+)
+
+// Backported from mautrix/go-util@e5cb5e96d15cb87ffe6e5970c2f90ee47980e715.
+
+// JSONPtr is a convenience function for wrapping a pointer to a value in the JSON utility, but removing typed nils
+// (i.e. preventing nils from turning into the string "null" in the database).
+func JSONPtr[T any](val *T) dbutil.JSON {
+	return dbutil.JSON{Data: UntypedNil(val)}
+}
+
+func UntypedNil[T any](val *T) any {
+	if val == nil {
+		return nil
+	}
+	return val
+}

database/upgrades/00-latest-revision.sql

@@ -1,4 +1,4 @@
--- v0 -> v23 (compatible with v19+): Latest revision
+-- v0 -> v24 (compatible with v19+): Latest revision
 
 CREATE TABLE guild (
     dcid       TEXT PRIMARY KEY,
@@ -92,7 +92,8 @@ CREATE TABLE "user" (
     space_room      TEXT,
     dm_space_room   TEXT,
 
-    read_state_version INTEGER NOT NULL DEFAULT 0
+    read_state_version INTEGER NOT NULL DEFAULT 0,
+    heartbeat_session jsonb
 );
 
 CREATE TABLE user_portal (

database/upgrades/24-user-heartbeat-session.sql

@@ -0,0 +1,2 @@
+-- v24 (compatible with v19+): Add persisted heartbeat sessions
+ALTER TABLE "user" ADD COLUMN heartbeat_session jsonb;

database/user.go

@@ -3,6 +3,7 @@ package database
 import (
 	"database/sql"
 
+	"github.com/bwmarrin/discordgo"
 	"go.mau.fi/util/dbutil"
 	log "maunium.net/go/maulogger/v2"
 	"maunium.net/go/mautrix/id"
@@ -21,18 +22,18 @@ func (uq *UserQuery) New() *User {
 }
 
 func (uq *UserQuery) GetByMXID(userID id.UserID) *User {
-	query := `SELECT mxid, dcid, discord_token, management_room, space_room, dm_space_room, read_state_version FROM "user" WHERE mxid=$1`
+	query := `SELECT mxid, dcid, discord_token, management_room, space_room, dm_space_room, read_state_version, heartbeat_session FROM "user" WHERE mxid=$1`
 	return uq.New().Scan(uq.db.QueryRow(query, userID))
 }
 
 func (uq *UserQuery) GetByID(id string) *User {
-	query := `SELECT mxid, dcid, discord_token, management_room, space_room, dm_space_room, read_state_version FROM "user" WHERE dcid=$1`
+	query := `SELECT mxid, dcid, discord_token, management_room, space_room, dm_space_room, read_state_version, heartbeat_session FROM "user" WHERE dcid=$1`
 	return uq.New().Scan(uq.db.QueryRow(query, id))
 }
 
 func (uq *UserQuery) GetAllWithToken() []*User {
 	query := `
-		SELECT mxid, dcid, discord_token, management_room, space_room, dm_space_room, read_state_version
+		SELECT mxid, dcid, discord_token, management_room, space_room, dm_space_room, read_state_version, heartbeat_session
 		FROM "user" WHERE discord_token IS NOT NULL
 	`
 	rows, err := uq.db.Query(query)
@@ -60,13 +61,14 @@ type User struct {
 	ManagementRoom   id.RoomID
 	SpaceRoom        id.RoomID
 	DMSpaceRoom      id.RoomID
+	HeartbeatSession *discordgo.HeartbeatSession
 
 	ReadStateVersion int
 }
 
 func (u *User) Scan(row dbutil.Scannable) *User {
 	var discordID, managementRoom, spaceRoom, dmSpaceRoom, discordToken sql.NullString
-	err := row.Scan(&u.MXID, &discordID, &discordToken, &managementRoom, &spaceRoom, &dmSpaceRoom, &u.ReadStateVersion)
+	err := row.Scan(&u.MXID, &discordID, &discordToken, &managementRoom, &spaceRoom, &dmSpaceRoom, &u.ReadStateVersion, dbutil.JSON{Data: &u.HeartbeatSession})
 	if err != nil {
 		if err != sql.ErrNoRows {
 			u.log.Errorln("Database scan failed:", err)
@@ -83,8 +85,8 @@ func (u *User) Scan(row dbutil.Scannable) *User {
 }
 
 func (u *User) Insert() {
-	query := `INSERT INTO "user" (mxid, dcid, discord_token, management_room, space_room, dm_space_room, read_state_version) VALUES ($1, $2, $3, $4, $5, $6, $7)`
-	_, err := u.db.Exec(query, u.MXID, strPtr(u.DiscordID), strPtr(u.DiscordToken), strPtr(string(u.ManagementRoom)), strPtr(string(u.SpaceRoom)), strPtr(string(u.DMSpaceRoom)), u.ReadStateVersion)
+	query := `INSERT INTO "user" (mxid, dcid, discord_token, management_room, space_room, dm_space_room, read_state_version, heartbeat_session) VALUES ($1, $2, $3, $4, $5, $6, $7, $8)`
+	_, err := u.db.Exec(query, u.MXID, strPtr(u.DiscordID), strPtr(u.DiscordToken), strPtr(string(u.ManagementRoom)), strPtr(string(u.SpaceRoom)), strPtr(string(u.DMSpaceRoom)), u.ReadStateVersion, JSONPtr(u.HeartbeatSession))
 	if err != nil {
 		u.log.Warnfln("Failed to insert %s: %v", u.MXID, err)
 		panic(err)
@@ -92,8 +94,8 @@ func (u *User) Insert() {
 }
 
 func (u *User) Update() {
-	query := `UPDATE "user" SET dcid=$1, discord_token=$2, management_room=$3, space_room=$4, dm_space_room=$5, read_state_version=$6 WHERE mxid=$7`
-	_, err := u.db.Exec(query, strPtr(u.DiscordID), strPtr(u.DiscordToken), strPtr(string(u.ManagementRoom)), strPtr(string(u.SpaceRoom)), strPtr(string(u.DMSpaceRoom)), u.ReadStateVersion, u.MXID)
+	query := `UPDATE "user" SET dcid=$1, discord_token=$2, management_room=$3, space_room=$4, dm_space_room=$5, read_state_version=$6, heartbeat_session=$7 WHERE mxid=$8`
+	_, err := u.db.Exec(query, strPtr(u.DiscordID), strPtr(u.DiscordToken), strPtr(string(u.ManagementRoom)), strPtr(string(u.SpaceRoom)), strPtr(string(u.DMSpaceRoom)), u.ReadStateVersion, JSONPtr(u.HeartbeatSession), u.MXID)
 	if err != nil {
 		u.log.Warnfln("Failed to update %q: %v", u.MXID, err)
 		panic(err)

directmedia.go

@@ -154,6 +154,7 @@ func newDirectMediaAPI(br *DiscordBridge) *DirectMediaAPI {
 	addRoutes("r0")
 	addRoutes("v1")
 	federationRouter.HandleFunc("/v1/media/download/{mediaID}", dma.DownloadMedia).Methods(http.MethodGet)
+	federationRouter.HandleFunc("/v1/media/thumbnail/{mediaID}", dma.DownloadMedia).Methods(http.MethodGet)
 	federationRouter.HandleFunc("/v1/version", dma.ks.GetServerVersion).Methods(http.MethodGet)
 	mediaRouter.NotFoundHandler = http.HandlerFunc(dma.UnknownEndpoint)
 	mediaRouter.MethodNotAllowedHandler = http.HandlerFunc(dma.UnsupportedMethod)
@@ -556,7 +557,7 @@ func (dma *DirectMediaAPI) proxyDownload(ctx context.Context, w http.ResponseWri
 func (dma *DirectMediaAPI) DownloadMedia(w http.ResponseWriter, r *http.Request) {
 	ctx := r.Context()
 	log := zerolog.Ctx(ctx)
-	isNewFederation := strings.HasPrefix(r.URL.Path, "/_matrix/federation/v1/media/download/")
+	isNewFederation := strings.HasPrefix(r.URL.Path, "/_matrix/federation/v1/media/")
 	vars := mux.Vars(r)
 	if !isNewFederation && vars["serverName"] != dma.cfg.ServerName {
 		jsonResponse(w, http.StatusNotFound, &mautrix.RespError{

example-config.yaml

@@ -130,7 +130,7 @@ bridge:
     message_error_notices: true
     # Should the bridge use space-restricted join rules instead of invite-only for guild rooms?
     # This can avoid unnecessary invite events in guild rooms when members are synced in.
-    restricted_rooms: true
+    restricted_rooms: false
     # Should the bridge automatically join the user to threads on Discord when the thread is opened on Matrix?
     # This only works with clients that support thread read receipts (MSC3771 added in Matrix v1.4).
     autojoin_thread_on_open: true

go.mod

@@ -1,8 +1,8 @@
 module go.mau.fi/mautrix-discord
 
-go 1.24.0
+go 1.25.0
 
-toolchain go1.25.0
+toolchain go1.26.0
 
 require (
 	github.com/bwmarrin/discordgo v0.27.0
@@ -26,6 +26,7 @@ require (
 require (
 	github.com/coreos/go-systemd/v22 v22.5.0 // indirect
 	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/google/uuid v1.6.0 // indirect
 	github.com/mattn/go-colorable v0.1.13 // indirect
 	github.com/mattn/go-isatty v0.0.19 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
@@ -42,4 +43,4 @@ require (
 	maunium.net/go/mauflag v1.0.0 // indirect
 )
 
-replace github.com/bwmarrin/discordgo => github.com/beeper/discordgo v0.0.0-20250607214857-f23a8518ece2
+replace github.com/bwmarrin/discordgo => github.com/beeper/discordgo v0.0.0-20260215125047-ccf8cbaa0a9f

go.sum

@@ -1,7 +1,7 @@
 github.com/DATA-DOG/go-sqlmock v1.5.0 h1:Shsta01QNfFxHCfpW6YH2STWB0MudeXXEWMr20OEh60=
 github.com/DATA-DOG/go-sqlmock v1.5.0/go.mod h1:f/Ixk793poVmq4qj/V1dPUg2JEAKC73Q5eFN3EC/SaM=
-github.com/beeper/discordgo v0.0.0-20250607214857-f23a8518ece2 h1:8lgTjYGSIlS90f0jiFfEC4UwxCq9FiUo4dKwjknbupQ=
-github.com/beeper/discordgo v0.0.0-20250607214857-f23a8518ece2/go.mod h1:59+AOzzjmL6onAh62nuLXmn7dJCaC/owDLWbGtjTcFA=
+github.com/beeper/discordgo v0.0.0-20260215125047-ccf8cbaa0a9f h1:A+SRmETpSnFixbP1x6u7sQdoi8cOuYfL5bkDJy9F/Pg=
+github.com/beeper/discordgo v0.0.0-20260215125047-ccf8cbaa0a9f/go.mod h1:lioivnibvB8j1KcF5TVpLdRLKCKHtcl8A03GpxRCre4=
 github.com/coreos/go-systemd/v22 v22.5.0 h1:RrqgGjYQKalulkV8NGVIfkXQf6YYmOyiJKk8iXXhfZs=
 github.com/coreos/go-systemd/v22 v22.5.0/go.mod h1:Y58oyj3AT4RCenI/lSvhwexgC+NSVTIJ3seZv2GcEnc=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
@@ -11,6 +11,8 @@ github.com/gabriel-vasile/mimetype v1.4.9/go.mod h1:WnSQhFKJuBlRyLiKohA/2DtIlPFA
 github.com/godbus/dbus/v5 v5.0.4/go.mod h1:xhWf0FNVPg57R7Z0UbKHbJfkEywrmjJnf7w5xrFpKfA=
 github.com/google/shlex v0.0.0-20191202100458-e7afc7fbc510 h1:El6M4kTTCOh6aBiKaUGG7oYTSPP8MxqL4YI3kZKwcP4=
 github.com/google/shlex v0.0.0-20191202100458-e7afc7fbc510/go.mod h1:pupxD2MaaD3pAXIBCelhxNneeOaAeabZDe5s4K6zSpQ=
+github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
+github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/gorilla/mux v1.8.0 h1:i40aqfkR1h2SlN9hojwV5ZA91wcXFOvkdNIeFDP5koI=
 github.com/gorilla/mux v1.8.0/go.mod h1:DVbg23sWSpFRCP0SfiEN6jmj59UnW/n46BH5rLB71So=
 github.com/gorilla/websocket v1.5.0 h1:PPwGk2jz7EePpoHN/+ClbZu8SPxiqlu12wZP/3sWmnc=

main.go

@@ -187,7 +187,7 @@ func main() {
 		Name:              "mautrix-discord",
 		URL:               "https://github.com/mautrix/discord",
 		Description:       "A Matrix-Discord puppeting bridge.",
-		Version:           "0.7.5",
+		Version:           "0.7.6",
 		ProtocolName:      "Discord",
 		BeeperServiceName: "discordgo",
 		BeeperNetworkName: "discord",

portal.go

@@ -1522,10 +1522,16 @@ func (portal *Portal) RefererOptIfUser(sess *discordgo.Session, threadID string)
 }
 
 func (portal *Portal) handleMatrixMessage(sender *User, evt *event.Event) {
-	if portal.IsPrivateChat() && sender.DiscordID != portal.Key.Receiver {
+	if portal.IsPrivateChat() {
+		if !sender.IsLoggedIn() {
+			go portal.sendMessageMetrics(evt, errUserNotLoggedIn, "Ignoring")
+			return
+		}
+		if sender.DiscordID != portal.Key.Receiver {
 			go portal.sendMessageMetrics(evt, errUserNotReceiver, "Ignoring")
 			return
 		}
+	}
 
 	content, ok := evt.Content.Parsed.(*event.MessageEventContent)
 	if !ok {
@@ -1650,13 +1656,18 @@ func (portal *Portal) handleMatrixMessage(sender *User, evt *event.Event) {
 				ID:                  "0",
 				Filename:            filename,
 				Description:         description,
+				OriginalContentType: content.Info.MimeType,
 			}
 			sendReq.Attachments = []*discordgo.MessageAttachment{att}
+			isClip := false
 			prep, err := sender.Session.ChannelAttachmentCreate(channelID, &discordgo.ReqPrepareAttachments{
 				Files: []*discordgo.FilePrepare{{
 					Size: len(data),
 					Name: att.Filename,
 					ID:   sender.NextDiscordUploadID(),
+
+					IsClip:              &isClip,
+					OriginalContentType: att.OriginalContentType,
 				}},
 			}, portal.RefererOpt(threadID))
 			if err != nil {
@@ -1918,12 +1929,13 @@ func (portal *Portal) getMatrixUsers() ([]id.UserID, error) {
 }
 
 func (portal *Portal) handleMatrixReaction(sender *User, evt *event.Event) {
+	if !sender.IsLoggedIn() {
+		go portal.sendMessageMetrics(evt, errUserNotLoggedIn, "Ignoring")
+		return
+	}
 	if portal.IsPrivateChat() && sender.DiscordID != portal.Key.Receiver {
 		go portal.sendMessageMetrics(evt, errUserNotReceiver, "Ignoring")
 		return
-	} else if !sender.IsLoggedIn() {
-		//go portal.sendMessageMetrics(evt, errReactionUserNotLoggedIn, "Ignoring")
-		return
 	}
 
 	reaction := evt.Content.AsReaction()
@@ -2101,10 +2113,16 @@ func (portal *Portal) handleDiscordReaction(user *User, reaction *discordgo.Mess
 }
 
 func (portal *Portal) handleMatrixRedaction(sender *User, evt *event.Event) {
-	if portal.IsPrivateChat() && sender.DiscordID != portal.Key.Receiver {
+	if portal.IsPrivateChat() {
+		if !sender.IsLoggedIn() {
+			go portal.sendMessageMetrics(evt, errUserNotLoggedIn, "Ignoring")
+			return
+		}
+		if sender.DiscordID != portal.Key.Receiver {
 			go portal.sendMessageMetrics(evt, errUserNotReceiver, "Ignoring")
 			return
 		}
+	}
 
 	sess := sender.Session
 	if sess == nil && portal.RelayWebhookID == "" {

user.go

@@ -550,6 +550,17 @@ func (user *User) Connect() error {
 	if err != nil {
 		return err
 	}
+
+	if user.HeartbeatSession == nil || user.HeartbeatSession.IsExpired() {
+		user.log.Debug().Msg("Creating new heartbeat session")
+		sess := discordgo.NewHeartbeatSession()
+		user.HeartbeatSession = &sess
+	}
+	user.HeartbeatSession.BumpLastUsed()
+	user.Update()
+	// make discordgo use our session instead of the one it creates automatically
+	session.HeartbeatSession = *user.HeartbeatSession
+
 	if user.bridge.Config.Bridge.Proxy != "" {
 		u, _ := url.Parse(user.bridge.Config.Bridge.Proxy)
 		tlsConf := &tls.Config{
@@ -569,7 +580,10 @@ func (user *User) Connect() error {
 	} else {
 		session.LogLevel = discordgo.LogInformational
 	}
-	userDiscordLog := user.log.With().Str("component", "discordgo").Logger()
+	userDiscordLog := user.log.With().
+		Str("component", "discordgo").
+		Str("heartbeat_session", session.HeartbeatSession.ID.String()).
+		Logger()
 	session.Logger = func(msgL, caller int, format string, a ...interface{}) {
 		userDiscordLog.WithLevel(discordToZeroLevel(msgL)).Caller(caller+1).Msgf(strings.TrimSpace(format), a...) // zerolog-allow-msgf
 	}
@@ -807,6 +821,7 @@ func (user *User) subscribeGuilds(delay time.Duration) {
 func (user *User) resumeHandler(_ *discordgo.Resumed) {
 	user.log.Debug().Msg("Discord connection resumed")
 	user.subscribeGuilds(0 * time.Second)
+	user.BridgeState.Send(status.BridgeState{StateEvent: status.StateConnected})
 }
 
 func (user *User) addPrivateChannelToSpace(portal *Portal) bool {
@@ -1007,7 +1022,6 @@ func (user *User) connectedHandler(_ *discordgo.Connect) {
 	user.log.Debug().Msg("Connected to Discord")
 	if user.wasDisconnected {
 		user.wasDisconnected = false
-		user.BridgeState.Send(status.BridgeState{StateEvent: status.StateConnected})
 	}
 }