Add support for message deletion (nctalk) (#1492)

* nctalk: add message deletion support

Signed-off-by: Gary Kim <gary@garykim.dev>

* nctalk: seperate out deletion and sending logic

Signed-off-by: Gary Kim <gary@garykim.dev>

* nctalk: update library to v0.2.0

Signed-off-by: Gary Kim <gary@garykim.dev>

* Rename functions to be clearer

Signed-off-by: Gary Kim <gary@garykim.dev>

* Update to go-nc-talk v0.2.1

Signed-off-by: Gary Kim <gary@garykim.dev>

* Update to go-nc-talk v0.2.2

Signed-off-by: Gary Kim <gary@garykim.dev>

* Make deletions easier to debug

Signed-off-by: Gary Kim <gary@garykim.dev>

bridge/nctalk/nctalk.go

@@ -74,12 +74,6 @@ func (b *Btalk) JoinChannel(channel config.ChannelInfo) error {
 	}
 	b.rooms = append(b.rooms, newRoom)
 
-	// Config
-	guestSuffix := " (Guest)"
-	if b.IsKeySet("GuestSuffix") {
-		guestSuffix = b.GetString("GuestSuffix")
-	}
-
 	go func() {
 		for msg := range c {
 			msg := msg
@@ -90,35 +84,23 @@ func (b *Btalk) JoinChannel(channel config.ChannelInfo) error {
 				return
 			}
 
-			// ignore messages that are one of the following
-			// * not a message from a user
-			// * from ourselves
-			if msg.MessageType != ocs.MessageComment || msg.ActorID == b.user.User {
-				continue
-			}
-			remoteMessage := config.Message{
-				Text:     formatRichObjectString(msg.Message, msg.MessageParameters),
-				Channel:  newRoom.room.Token,
-				Username: DisplayName(msg, guestSuffix),
-				UserID:   msg.ActorID,
-				Account:  b.Account,
-			}
-			// It is possible for the ID to not be set on older versions of Talk so we only set it if
-			// the ID is not blank
-			if msg.ID != 0 {
-				remoteMessage.ID = strconv.Itoa(msg.ID)
-			}
-
-			// Handle Files
-			err = b.handleFiles(&remoteMessage, &msg)
-			if err != nil {
-				b.Log.Errorf("Error handling file: %#v", msg)
-
+			// Ignore messages that are from the bot user
+			if msg.ActorID == b.user.User {
+				continue
+			}
+
+			// Handle deleting messages
+			if msg.MessageType == ocs.MessageSystem && msg.Parent != nil && msg.Parent.MessageType == ocs.MessageDelete {
+				b.handleDeletingMessage(&msg, &newRoom)
+				continue
+			}
+
+			// Handle sending messages
+			if msg.MessageType == ocs.MessageComment {
+				b.handleSendingMessage(&msg, &newRoom)
 				continue
 			}
 
-			b.Log.Debugf("<= Message is %#v", remoteMessage)
-			b.Remote <- remoteMessage
 		}
 	}()
 	return nil
@@ -131,11 +113,8 @@ func (b *Btalk) Send(msg config.Message) (string, error) {
 		return "", nil
 	}
 
-	// Talk currently only supports sending normal messages
-	if msg.Event != "" {
-		return "", nil
-	}
-
+	// Standard Message Send
+	if msg.Event == "" {
 		// Handle sending files if they are included
 		err := b.handleSendingFile(&msg, r)
 		if err != nil {
@@ -153,6 +132,23 @@ func (b *Btalk) Send(msg config.Message) (string, error) {
 		return strconv.Itoa(sentMessage.ID), nil
 	}
 
+	// Message Deletion
+	if msg.Event == config.EventMsgDelete {
+		messageID, err := strconv.Atoi(msg.ID)
+		if err != nil {
+			return "", err
+		}
+		data, err := r.room.DeleteMessage(messageID)
+		if err != nil {
+			return "", err
+		}
+		return strconv.Itoa(data.ID), nil
+	}
+
+	// Message is not a type that is currently supported
+	return "", nil
+}
+
 func (b *Btalk) getRoom(token string) *Broom {
 	for _, r := range b.rooms {
 		if r.room.Token == token {
@@ -208,6 +204,53 @@ func (b *Btalk) handleSendingFile(msg *config.Message, r *Broom) error {
 	return nil
 }
 
+func (b *Btalk) handleSendingMessage(msg *ocs.TalkRoomMessageData, r *Broom) {
+	remoteMessage := config.Message{
+		Text:     formatRichObjectString(msg.Message, msg.MessageParameters),
+		Channel:  r.room.Token,
+		Username: DisplayName(msg, b.guestSuffix()),
+		UserID:   msg.ActorID,
+		Account:  b.Account,
+	}
+	// It is possible for the ID to not be set on older versions of Talk so we only set it if
+	// the ID is not blank
+	if msg.ID != 0 {
+		remoteMessage.ID = strconv.Itoa(msg.ID)
+	}
+
+	// Handle Files
+	err := b.handleFiles(&remoteMessage, msg)
+	if err != nil {
+		b.Log.Errorf("Error handling file: %#v", msg)
+
+		return
+	}
+
+	b.Log.Debugf("<= Message is %#v", remoteMessage)
+	b.Remote <- remoteMessage
+}
+
+func (b *Btalk) handleDeletingMessage(msg *ocs.TalkRoomMessageData, r *Broom) {
+	remoteMessage := config.Message{
+		Event:   config.EventMsgDelete,
+		Text:    config.EventMsgDelete,
+		Channel: r.room.Token,
+		ID:      strconv.Itoa(msg.Parent.ID),
+		Account: b.Account,
+	}
+	b.Log.Debugf("<= Message being deleted is %#v", remoteMessage)
+	b.Remote <- remoteMessage
+}
+
+func (b *Btalk) guestSuffix() string {
+	guestSuffix := " (Guest)"
+	if b.IsKeySet("GuestSuffix") {
+		guestSuffix = b.GetString("GuestSuffix")
+	}
+
+	return guestSuffix
+}
+
 // Spec: https://github.com/nextcloud/server/issues/1706#issue-182308785
 func formatRichObjectString(message string, parameters map[string]ocs.RichObjectString) string {
 	for id, parameter := range parameters {
@@ -228,7 +271,7 @@ func formatRichObjectString(message string, parameters map[string]ocs.RichObject
 	return message
 }
 
-func DisplayName(msg ocs.TalkRoomMessageData, suffix string) string {
+func DisplayName(msg *ocs.TalkRoomMessageData, suffix string) string {
 	if msg.ActorType == ocs.ActorGuest {
 		if msg.ActorDisplayName == "" {
 			return "Guest"

go.mod

@@ -57,7 +57,7 @@ require (
 	github.com/zfjagann/golang-ring v0.0.0-20210116075443-7c86fdb43134
 	golang.org/x/image v0.0.0-20210504121937-7319ad40d33e
 	golang.org/x/oauth2 v0.0.0-20210514164344-f6687ab2804c
-	gomod.garykim.dev/nc-talk v0.1.7
+	gomod.garykim.dev/nc-talk v0.2.2
 	gopkg.in/olahol/melody.v1 v1.0.0-20170518105555-d52139073376
 	layeh.com/gumble v0.0.0-20200818122324-146f9205029b
 )

go.sum

@@ -1278,8 +1278,8 @@ golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8T
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 h1:go1bK/D/BFZV2I8cIQd1NKEZ+0owSTG1fDTci4IqFcE=
 golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
-gomod.garykim.dev/nc-talk v0.1.7 h1:G2qsiRcyaj5FEADQlulsBAFJHs27tPmH9VtKK+at9SM=
-gomod.garykim.dev/nc-talk v0.1.7/go.mod h1:DNucAJ6zeaumBEwV5NiYk+Eea8Ca+Q5f+plhz9F7d58=
+gomod.garykim.dev/nc-talk v0.2.2 h1:+U+daJFPPuwM7yRXYazeMHZgIBSGP6SeQURO0O5a32I=
+gomod.garykim.dev/nc-talk v0.2.2/go.mod h1:q/Adot/H7iqi+H4lANopV7/xcMf+sX3AZXUXqiITwok=
 google.golang.org/api v0.0.0-20180910000450-7ca32eb868bf/go.mod h1:4mhQ8q/RsB7i+udVvVy5NUi08OU8ZlA0gRVgrF7VFY0=
 google.golang.org/api v0.0.0-20181030000543-1d582fd0359e/go.mod h1:4mhQ8q/RsB7i+udVvVy5NUi08OU8ZlA0gRVgrF7VFY0=
 google.golang.org/api v0.0.0-20181220000619-583d854617af/go.mod h1:4mhQ8q/RsB7i+udVvVy5NUi08OU8ZlA0gRVgrF7VFY0=

vendor/gomod.garykim.dev/nc-talk/ocs/capabilities.go

@@ -34,9 +34,13 @@ type SpreedCapabilities struct {
 		} `json:"attachments"`
 		Chat struct {
 			MaxLength   int `json:"max-length"`
+			ReadPrivacy int `json:"read-privacy"`
 		} `json:"chat"`
 		Conversations struct {
 			CanCreate bool `json:"can-create"`
 		} `json:"conversations"`
+		Previews struct {
+			MaxGifSize int `json:"max-gif-size"`
+		} `json:"previews"`
 	} `json:"config"`
 }

vendor/gomod.garykim.dev/nc-talk/ocs/message.go

@@ -35,6 +35,15 @@ const (
 	// MessageCommand is a Nextcloud Talk message that is a command
 	MessageCommand MessageType = "command"
 
+	// MessageDelete is a Nextcloud Talk message indicating a message that was deleted
+	//
+	// If a message has been deleted, a message of MessageType MessageSystem is
+	// sent through the channel for which the parent message's MessageType is MessageDelete.
+	// So, in order to check if a new message is a message deletion request, a check
+	// like this can be used:
+	// msg.MessageType == ocs.MessageSystem && msg.Parent != nil && msg.Parent.MessageType == ocs.MessageDelete
+	MessageDelete MessageType = "comment_deleted"
+
 	// ActorUser is a Nextcloud Talk message sent by a user
 	ActorUser ActorType = "users"
 
@@ -55,6 +64,8 @@ type TalkRoomMessageData struct {
 	SystemMessage     string                      `json:"systemMessage"`
 	Timestamp         int                         `json:"timestamp"`
 	MessageType       MessageType                 `json:"messageType"`
+	Deleted           bool                        `json:"deleted"`
+	Parent            *TalkRoomMessageData        `json:"parent"`
 	MessageParameters map[string]RichObjectString `json:"-"`
 }
 

vendor/gomod.garykim.dev/nc-talk/room/room.go

@@ -18,6 +18,7 @@ import (
 	"context"
 	"errors"
 	"io/ioutil"
+	"net/http"
 	"strconv"
 	"time"
 
@@ -41,6 +42,12 @@ var (
 	ErrUnexpectedReturnCode = errors.New("unexpected return code")
 	// ErrTooManyRequests is returned if the server returns a 429
 	ErrTooManyRequests = errors.New("too many requests")
+	// ErrLackingCapabilities is returned if the server lacks the required capability for the given function
+	ErrLackingCapabilities = errors.New("lacking required capabilities")
+	// ErrForbidden is returned if the user is forbidden from accessing the requested resource
+	ErrForbidden = errors.New("request forbidden")
+	// ErrUnexpectedResponse is returned if the response from the Nextcloud Talk server is not formatted as expected
+	ErrUnexpectedResponse = errors.New("unexpected response")
 )
 
 // TalkRoom represents a room in Nextcloud Talk
@@ -90,6 +97,39 @@ func (t *TalkRoom) SendMessage(msg string) (*ocs.TalkRoomMessageData, error) {
 	return &msgInfo.OCS.TalkRoomMessage, err
 }
 
+// DeleteMessage deletes the message with the given messageID on the server.
+//
+// Requires "delete-messages" capability on the Nextcloud Talk server
+func (t *TalkRoom) DeleteMessage(messageID int) (*ocs.TalkRoomMessageData, error) {
+	// Check for required capability
+	capable, err := t.User.Capabilities()
+	if err != nil {
+		return nil, err
+	}
+	if !capable.DeleteMessages {
+		return nil, ErrLackingCapabilities
+	}
+
+	url := t.User.NextcloudURL + constants.BaseEndpoint + "/chat/" + t.Token + "/" + strconv.Itoa(messageID)
+
+	client := t.User.RequestClient(request.Client{
+		URL:    url,
+		Method: "DELETE",
+	})
+	res, err := client.Do()
+	if err != nil {
+		return nil, err
+	}
+	if res.StatusCode() != http.StatusOK && res.StatusCode() != http.StatusAccepted {
+		return nil, ErrUnexpectedReturnCode
+	}
+	msgInfo, err := ocs.TalkRoomSentResponseUnmarshal(&res.Data)
+	if err != nil {
+		return nil, err
+	}
+	return &msgInfo.OCS.TalkRoomMessage, nil
+}
+
 // ReceiveMessages starts watching for new messages
 func (t *TalkRoom) ReceiveMessages(ctx context.Context) (chan ocs.TalkRoomMessageData, error) {
 	c := make(chan ocs.TalkRoomMessageData)
@@ -133,23 +173,28 @@ func (t *TalkRoom) ReceiveMessages(ctx context.Context) (chan ocs.TalkRoomMessag
 			}
 
 			// If it seems that we no longer have access to the chat for one reason or another, stop the goroutine and set error in the next return.
-			if res.StatusCode == 404 {
+			if res.StatusCode == http.StatusNotFound {
 				_ = res.Body.Close()
 				c <- ocs.TalkRoomMessageData{Error: ErrRoomNotFound}
 				return
 			}
-			if res.StatusCode == 401 {
+			if res.StatusCode == http.StatusUnauthorized {
 				_ = res.Body.Close()
 				c <- ocs.TalkRoomMessageData{Error: ErrUnauthorized}
 				return
 			}
-			if res.StatusCode == 429 {
+			if res.StatusCode == http.StatusTooManyRequests {
 				_ = res.Body.Close()
 				c <- ocs.TalkRoomMessageData{Error: ErrTooManyRequests}
 				return
 			}
+			if res.StatusCode == http.StatusForbidden {
+				_ = res.Body.Close()
+				c <- ocs.TalkRoomMessageData{Error: ErrForbidden}
+				return
+			}
 
-			if res.StatusCode == 200 {
+			if res.StatusCode == http.StatusOK {
 				lastKnown = res.Header.Get("X-Chat-Last-Given")
 				data, err := ioutil.ReadAll(res.Body)
 				_ = res.Body.Close()
@@ -192,13 +237,13 @@ func (t *TalkRoom) TestConnection() error {
 		return err
 	}
 	switch res.StatusCode() {
-	case 200:
+	case http.StatusOK:
 		return nil
-	case 304:
+	case http.StatusNotModified:
 		return nil
-	case 404:
+	case http.StatusNotFound:
 		return ErrRoomNotFound
-	case 412:
+	case http.StatusPreconditionFailed:
 		return ErrNotModeratorInLobby
 	}
 	return ErrUnexpectedReturnCode

vendor/gomod.garykim.dev/nc-talk/user/user.go

@@ -28,12 +28,16 @@ import (
 
 const (
 	ocsCapabilitiesEndpoint = "/ocs/v2.php/cloud/capabilities"
-	ocsRoomsEndpoint        = "/ocs/v2.php/apps/spreed/api/v2/room"
+	ocsRoomsv2Endpoint      = "/ocs/v2.php/apps/spreed/api/v2/room"
+	ocsRoomsv4Endpoint      = "/ocs/v2.php/apps/spreed/api/v4/room"
 )
 
 var (
-	// ErrUserIsNil is returned when a funciton is called with an nil user.
+	// ErrUserIsNil is returned when a function is called with an nil user.
 	ErrUserIsNil = errors.New("user is nil")
+
+	// ErrCannotDownloadFile is returned when a function cannot download the requested file
+	ErrCannotDownloadFile = errors.New("cannot download file")
 )
 
 // TalkUser represents a user of Nextcloud Talk
@@ -53,7 +57,6 @@ type TalkUserConfig struct {
 // Capabilities describes the capabilities that the Nextcloud Talk instance is capable of. Visit https://nextcloud-talk.readthedocs.io/en/latest/capabilities/ for more info.
 type Capabilities struct {
 	AttachmentsFolder      string `ocscapability:"config => attachments => folder"`
-	ChatMaxLength          int
 	Audio                  bool   `ocscapability:"audio"`
 	Video                  bool   `ocscapability:"video"`
 	Chat                   bool   `ocscapability:"chat"`
@@ -83,6 +86,23 @@ type Capabilities struct {
 	ForceMute              bool   `ocscapability:"force-mute"`
 	ConversationV2         bool   `ocscapability:"conversation-v2"`
 	ChatReferenceID        bool   `ocscapability:"chat-reference-id"`
+	ConversationV3         bool   `ocscapability:"conversation-v3"`
+	ConversationV4         bool   `ocscapability:"conversation-v4"`
+	SIPSupport             bool   `ocscapability:"sip-support"`
+	ChatReadStatus         bool   `ocscapability:"chat-read-status"`
+	ListableRooms          bool   `ocscapability:"listable-rooms"`
+	PhonebookSearch        bool   `ocscapability:"phonebook-search"`
+	RaiseHand              bool   `ocscapability:"raise-hand"`
+	RoomDescription        bool   `ocscapability:"room-description"`
+	DeleteMessages         bool   `ocscapability:"delete-messages"`
+	RichObjectSharing      bool   `ocscapability:"rich-object-sharing"`
+	ConversationCallFlags  bool   `ocscapability:"conversation-call-flags"`
+	GeoLocationSharing     bool   `ocscapability:"geo-location-sharing"`
+	ReadPrivacyConfig      bool   `ocscapability:"config => chat => read-privacy"`
+	SignalingV3            bool   `ocscapability:"signaling-v3"`
+	TempUserAvatarAPI      bool   `ocscapability:"temp-user-avatar-api"`
+	MaxGifSizeConfig       int    `ocscapability:"config => previews => max-gif-size"`
+	ChatMaxLength          int    `ocscapability:"config => chat => max-length"`
 }
 
 // RoomInfo contains information about a room
@@ -160,8 +180,17 @@ func (t *TalkUser) RequestClient(client request.Client) *request.Client {
 
 // GetRooms returns a list of all rooms the user is in
 func (t *TalkUser) GetRooms() (*[]RoomInfo, error) {
+	endpoint := ocsRoomsv2Endpoint
+	capabilities, err := t.Capabilities()
+	if err != nil {
+		return nil, err
+	}
+	if capabilities.ConversationV4 {
+		endpoint = ocsRoomsv4Endpoint
+	}
+
 	client := t.RequestClient(request.Client{
-		URL: ocsRoomsEndpoint,
+		URL: endpoint,
 	})
 	res, err := client.Do()
 	if err != nil {
@@ -239,6 +268,22 @@ func (t *TalkUser) Capabilities() (*Capabilities, error) {
 		ConversationV2:         sliceContains(sc.Features, "conversation-v2"),
 		ChatReferenceID:        sliceContains(sc.Features, "chat-reference-id"),
 		ChatMaxLength:          sc.Config.Chat.MaxLength,
+		ConversationV3:         sliceContains(sc.Features, "conversation-v3"),
+		ConversationV4:         sliceContains(sc.Features, "conversation-v4"),
+		SIPSupport:             sliceContains(sc.Features, "sip-support"),
+		ChatReadStatus:         sliceContains(sc.Features, "chat-read-status"),
+		ListableRooms:          sliceContains(sc.Features, "listable-rooms"),
+		PhonebookSearch:        sliceContains(sc.Features, "phonebook-search"),
+		RaiseHand:              sliceContains(sc.Features, "raise-hand"),
+		RoomDescription:        sliceContains(sc.Features, "room-description"),
+		ReadPrivacyConfig:      sc.Config.Chat.ReadPrivacy != 0,
+		MaxGifSizeConfig:       sc.Config.Previews.MaxGifSize,
+		DeleteMessages:         sliceContains(sc.Features, "delete-messages"),
+		RichObjectSharing:      sliceContains(sc.Features, "rich-object-sharing"),
+		ConversationCallFlags:  sliceContains(sc.Features, "conversation-call-flags"),
+		GeoLocationSharing:     sliceContains(sc.Features, "geo-location-sharing"),
+		SignalingV3:            sliceContains(sc.Features, "signaling-v3"),
+		TempUserAvatarAPI:      sliceContains(sc.Features, "temp-user-avatar-api"),
 	}
 
 	t.capabilities = tr
@@ -264,7 +309,11 @@ func (t *TalkUser) DownloadFile(path string) (data *[]byte, err error) {
 		URL: url,
 	})
 	res, err := c.Do()
-	if err != nil || res.StatusCode() != 200 {
+	if err != nil {
+		return
+	}
+	if res.StatusCode() != 200 {
+		err = ErrCannotDownloadFile
 		return
 	}
 	data = &res.Data

vendor/modules.txt

@@ -395,7 +395,7 @@ golang.org/x/text/unicode/norm
 golang.org/x/text/width
 # golang.org/x/time v0.0.0-20201208040808-7e3f01d25324
 golang.org/x/time/rate
-# gomod.garykim.dev/nc-talk v0.1.7
+# gomod.garykim.dev/nc-talk v0.2.2
 ## explicit
 gomod.garykim.dev/nc-talk/constants
 gomod.garykim.dev/nc-talk/ocs