Download (and upload) avatar images from mattermost and telegram when mediaserver is configured. Closes #362

An extra avatarMap (cache) is created for mattermost and telegram.
If MediaServerUpload is configured, the avatar images of users are downloaded the first time a
user sends a message.
If this download succeeds a message with EVENT_AVATAR_DOWNLOAD is sent to the originating protocol.
This message also contains a SHA field (in msg.Extra["file"]), if this is not empty, the sha will
be added to the avatarMap. (so we now have a userid-sha cache)

Next time this user sends a message, the MediaServerUpload/sha/userid.png URL will be used as the
avatar field.

4 files changed, 106 insertions, 5 deletions

diff --git a/bridge/config/config.go b/bridge/config/config.go
index 1cf0b9f5..c5d4f543 100644
--- a/bridge/config/config.go
+++ b/bridge/config/config.go
@@ -14,6 +14,7 @@ const (
 	EVENT_TOPIC_CHANGE      = "topic_change"
 	EVENT_FAILURE           = "failure"
 	EVENT_FILE_FAILURE_SIZE = "file_failure_size"
+	EVENT_AVATAR_DOWNLOAD   = "avatar_download"
 	EVENT_REJOIN_CHANNELS   = "rejoin_channels"
 	EVENT_USER_ACTION       = "user_action"
 	EVENT_MSG_DELETE        = "msg_delete"
diff --git a/bridge/helper/helper.go b/bridge/helper/helper.go
index 10c3647a..44052e11 100644
--- a/bridge/helper/helper.go
+++ b/bridge/helper/helper.go
@@ -54,3 +54,10 @@ func HandleExtra(msg *config.Message, general *config.Protocol) []config.Message
 	}
 	return rmsg
 }
+
+func GetAvatar(av map[string]string, userid string, general *config.Protocol) string {
+	if sha, ok := av[userid]; ok {
+		return general.MediaServerUpload + "/" + sha + "/" + userid + ".png"
+	}
+	return ""
+}
diff --git a/bridge/mattermost/mattermost.go b/bridge/mattermost/mattermost.go
index 1f42b437..e60a136e 100644
--- a/bridge/mattermost/mattermost.go
+++ b/bridge/mattermost/mattermost.go
@@ -35,6 +35,7 @@ type Bmattermost struct {
 	MMapi
 	TeamId string
 	*config.BridgeConfig
+	avatarMap map[string]string
 }
 
 var flog *log.Entry
@@ -45,7 +46,7 @@ func init() {
 }
 
 func New(cfg *config.BridgeConfig) *Bmattermost {
-	b := &Bmattermost{BridgeConfig: cfg}
+	b := &Bmattermost{BridgeConfig: cfg, avatarMap: make(map[string]string)}
 	b.mmMap = make(map[string]string)
 	return b
 }
@@ -149,6 +150,18 @@ func (b *Bmattermost) Send(msg config.Message) (string, error) {
 	message := msg.Text
 	channel := msg.Channel
 
+	// map the file SHA to our user (caches the avatar)
+	if msg.Event == config.EVENT_AVATAR_DOWNLOAD {
+		fi := msg.Extra["file"][0].(config.FileInfo)
+		/* if we have a sha we have successfully uploaded the file to the media server,
+		so we can now cache the sha */
+		if fi.SHA != "" {
+			flog.Debugf("Added %s to %s in avatarMap", fi.SHA, msg.UserID)
+			b.avatarMap[msg.UserID] = fi.SHA
+		}
+		return "", nil
+	}
+
 	if b.Config.PrefixMessagesWithNick {
 		message = nick + message
 	}
@@ -235,7 +248,8 @@ func (b *Bmattermost) handleMatter() {
 		go b.handleMatterClient(mchan)
 	}
 	for message := range mchan {
-		rmsg := config.Message{Username: message.Username, Channel: message.Channel, Account: b.Account, UserID: message.UserID, ID: message.ID, Event: message.Event, Extra: message.Extra}
+		avatar := helper.GetAvatar(b.avatarMap, message.UserID, b.General)
+		rmsg := config.Message{Username: message.Username, Channel: message.Channel, Account: b.Account, UserID: message.UserID, ID: message.ID, Event: message.Event, Extra: message.Extra, Avatar: avatar}
 		text, ok := b.replaceAction(message.Text)
 		if ok {
 			rmsg.Event = config.EVENT_USER_ACTION
@@ -261,6 +275,11 @@ func (b *Bmattermost) handleMatterClient(mchan chan *MMMessage) {
 			continue
 		}
 
+		// only download avatars if we have a place to upload them (configured mediaserver)
+		if b.General.MediaServerUpload != "" {
+			b.handleDownloadAvatar(message.UserID, message.Channel)
+		}
+
 		m := &MMMessage{Extra: make(map[string][]interface{})}
 
 		props := message.Post.Props
@@ -365,3 +384,27 @@ func (b *Bmattermost) replaceAction(text string) (string, bool) {
 	}
 	return text, false
 }
+
+// handleDownloadAvatar downloads the avatar of userid from channel
+// sends a EVENT_AVATAR_DOWNLOAD message to the gateway if successful.
+// logs an error message if it fails
+func (b *Bmattermost) handleDownloadAvatar(userid string, channel string) {
+	var name string
+	msg := config.Message{Username: "system", Text: "avatar", Channel: channel, Account: b.Account, UserID: userid, Event: config.EVENT_AVATAR_DOWNLOAD, Extra: make(map[string][]interface{})}
+	if _, ok := b.avatarMap[userid]; !ok {
+		data, resp := b.mc.Client.GetProfileImage(userid, "")
+		if resp.Error != nil {
+			flog.Errorf("ProfileImage download failed for %#v %s", userid, resp.Error)
+		}
+		if len(data) <= b.General.MediaDownloadSize {
+			name = userid + ".png"
+			flog.Debugf("download OK %#v %#v", name, len(data))
+			msg.Extra["file"] = append(msg.Extra["file"], config.FileInfo{Name: name, Data: &data, Avatar: true})
+			flog.Debugf("Sending avatar download message from %#v on %s to gateway", userid, b.Account)
+			flog.Debugf("Message is %#v", msg)
+			b.Remote <- msg
+		} else {
+			flog.Errorf("File %#v to large to download (%#v). MediaDownloadSize is %#v", name, len(data), b.General.MediaDownloadSize)
+		}
+	}
+}
diff --git a/bridge/telegram/telegram.go b/bridge/telegram/telegram.go
index dfb596aa..ef310ef3 100644
--- a/bridge/telegram/telegram.go
+++ b/bridge/telegram/telegram.go
@@ -14,6 +14,7 @@ import (
 type Btelegram struct {
 	c *tgbotapi.BotAPI
 	*config.BridgeConfig
+	avatarMap map[string]string // keep cache of userid and avatar sha
 }
 
 var flog *log.Entry
@@ -24,7 +25,7 @@ func init() {
 }
 
 func New(cfg *config.BridgeConfig) *Btelegram {
-	return &Btelegram{BridgeConfig: cfg}
+	return &Btelegram{BridgeConfig: cfg, avatarMap: make(map[string]string)}
 }
 
 func (b *Btelegram) Connect() error {
@@ -63,6 +64,18 @@ func (b *Btelegram) Send(msg config.Message) (string, error) {
 		return "", err
 	}
 
+	// map the file SHA to our user (caches the avatar)
+	if msg.Event == config.EVENT_AVATAR_DOWNLOAD {
+		fi := msg.Extra["file"][0].(config.FileInfo)
+		/* if we have a sha we have successfully uploaded the file to the media server,
+		so we can now cache the sha */
+		if fi.SHA != "" {
+			flog.Debugf("Added %s to %s in avatarMap", fi.SHA, msg.UserID)
+			b.avatarMap[msg.UserID] = fi.SHA
+		}
+		return "", nil
+	}
+
 	if b.Config.MessageFormat == "HTML" {
 		msg.Text = makeHTML(msg.Text)
 	}
@@ -173,6 +186,10 @@ func (b *Btelegram) handleRecv(updates <-chan tgbotapi.Update) {
 			}
 			text = message.Text
 			channel = strconv.FormatInt(message.Chat.ID, 10)
+			// only download avatars if we have a place to upload them (configured mediaserver)
+			if b.General.MediaServerUpload != "" {
+				b.handleDownloadAvatar(message.From.ID, channel)
+			}
 		}
 
 		if username == "" {
@@ -235,8 +252,9 @@ func (b *Btelegram) handleRecv(updates <-chan tgbotapi.Update) {
 		}
 
 		if text != "" || len(fmsg.Extra) > 0 {
+			avatar := helper.GetAvatar(b.avatarMap, strconv.Itoa(message.From.ID), b.General)
 			flog.Debugf("Sending message from %s on %s to gateway", username, b.Account)
-			msg := config.Message{Username: username, Text: text, Channel: channel, Account: b.Account, UserID: strconv.Itoa(message.From.ID), ID: strconv.Itoa(message.MessageID), Extra: fmsg.Extra}
+			msg := config.Message{Username: username, Text: text, Channel: channel, Account: b.Account, UserID: strconv.Itoa(message.From.ID), ID: strconv.Itoa(message.MessageID), Extra: fmsg.Extra, Avatar: avatar}
 			flog.Debugf("Message is %#v", msg)
 			b.Remote <- msg
 		}
@@ -251,6 +269,39 @@ func (b *Btelegram) getFileDirectURL(id string) string {
 	return res
 }
 
+// handleDownloadAvatar downloads the avatar of userid from channel
+// sends a EVENT_AVATAR_DOWNLOAD message to the gateway if successful.
+// logs an error message if it fails
+func (b *Btelegram) handleDownloadAvatar(userid int, channel string) {
+	msg := config.Message{Username: "system", Text: "avatar", Channel: channel, Account: b.Account, UserID: strconv.Itoa(userid), Event: config.EVENT_AVATAR_DOWNLOAD, Extra: make(map[string][]interface{})}
+	if _, ok := b.avatarMap[strconv.Itoa(userid)]; !ok {
+		photos, err := b.c.GetUserProfilePhotos(tgbotapi.UserProfilePhotosConfig{UserID: userid, Limit: 1})
+		if err != nil {
+			flog.Errorf("Userprofile download failed for %#v %s", userid, err)
+		}
+		if len(photos.Photos) > 0 {
+			photo := photos.Photos[0][0]
+			url := b.getFileDirectURL(photo.FileID)
+			name := strconv.Itoa(userid) + ".png"
+			flog.Debugf("trying to download %#v fileid %#v with size %#v", name, photo.FileID, photo.FileSize)
+			if photo.FileSize <= b.General.MediaDownloadSize {
+				data, err := helper.DownloadFile(url)
+				if err != nil {
+					flog.Errorf("download %s failed %#v", url, err)
+				} else {
+					flog.Debugf("download OK %#v %#v %#v", name, len(*data), len(url))
+					msg.Extra["file"] = append(msg.Extra["file"], config.FileInfo{Name: name, Data: data, Avatar: true})
+					flog.Debugf("Sending avatar download message from %#v on %s to gateway", userid, b.Account)
+					flog.Debugf("Message is %#v", msg)
+					b.Remote <- msg
+				}
+			} else {
+				flog.Errorf("File %#v to large to download (%#v). MediaDownloadSize is %#v", name, photo.FileSize, b.General.MediaDownloadSize)
+			}
+		}
+	}
+}
+
 func (b *Btelegram) handleDownload(file interface{}, comment string, msg *config.Message) {
 	size := 0
 	url := ""
@@ -311,7 +362,6 @@ func (b *Btelegram) handleDownload(file interface{}, comment string, msg *config
 		return
 	}
 	// if we have a file attached, download it (in memory) and put a pointer to it in msg.Extra
-	// limit to 1MB for now
 	flog.Debugf("trying to download %#v fileid %#v with size %#v", name, fileid, size)
 	if size <= b.General.MediaDownloadSize {
 		data, err := helper.DownloadFile(url)