package bslack import ( "errors" "fmt" "html" "time" "github.com/42wim/matterbridge/bridge/config" "github.com/42wim/matterbridge/bridge/helper" "github.com/slack-go/slack" ) // ErrEventIgnored is for events that should be ignored var ErrEventIgnored = errors.New("this event message should ignored") func (b *Bslack) handleSlack() { messages := make(chan *config.Message) if b.GetString(incomingWebhookConfig) != "" { b.Log.Debugf("Choosing webhooks based receiving") go b.handleMatterHook(messages) } else { b.Log.Debugf("Choosing token based receiving") go b.handleSlackClient(messages) } time.Sleep(time.Second) b.Log.Debug("Start listening for Slack messages") for message := range messages { // don't do any action on deleted/typing messages if message.Event != config.EventUserTyping && message.Event != config.EventMsgDelete { b.Log.Debugf("<= Sending message from %s on %s to gateway", message.Username, b.Account) // cleanup the message message.Text = b.replaceMention(message.Text) message.Text = b.replaceVariable(message.Text) message.Text = b.replaceChannel(message.Text) message.Text = b.replaceURL(message.Text) message.Text = b.replaceb0rkedMarkDown(message.Text) message.Text = html.UnescapeString(message.Text) // Add the avatar message.Avatar = b.users.getAvatar(message.UserID) } b.Log.Debugf("<= Message is %#v", message) b.Remote <- *message } } func (b *Bslack) handleSlackClient(messages chan *config.Message) { for msg := range b.rtm.IncomingEvents { if msg.Type != sUserTyping && msg.Type != sHello && msg.Type != sLatencyReport { b.Log.Debugf("== Receiving event %#v", msg.Data) } switch ev := msg.Data.(type) { case *slack.UserTypingEvent: if !b.GetBool("ShowUserTyping") { continue } rmsg, err := b.handleTypingEvent(ev) if err == ErrEventIgnored { continue } else if err != nil { b.Log.Errorf("%#v", err) continue } messages <- rmsg case *slack.MessageEvent: if b.skipMessageEvent(ev) { b.Log.Debugf("Skipped message: %#v", ev) continue } rmsg, err := b.handleMessageEvent(ev) if err != nil { b.Log.Errorf("%#v", err) continue } messages <- rmsg case *slack.OutgoingErrorEvent: b.Log.Debugf("%#v", ev.Error()) case *slack.ChannelJoinedEvent: // When we join a channel we update the full list of users as // well as the information for the channel that we joined as this // should now tell that we are a member of it. b.channels.registerChannel(ev.Channel) case *slack.ConnectedEvent: b.si = ev.Info b.channels.populateChannels(true) b.users.populateUsers(true) case *slack.InvalidAuthEvent: b.Log.Fatalf("Invalid Token %#v", ev) case *slack.ConnectionErrorEvent: b.Log.Errorf("Connection failed %#v %#v", ev.Error(), ev.ErrorObj) case *slack.MemberJoinedChannelEvent: b.users.populateUser(ev.User) case *slack.HelloEvent, *slack.LatencyReport, *slack.ConnectingEvent: continue default: b.Log.Debugf("Unhandled incoming event: %T", ev) } } } func (b *Bslack) handleMatterHook(messages chan *config.Message) { for { message := b.mh.Receive() b.Log.Debugf("receiving from matterhook (slack) %#v", message) if message.UserName == "slackbot" { continue } messages <- &config.Message{ Username: message.UserName, Text: message.Text, Channel: message.ChannelName, } } } // skipMessageEvent skips event that need to be skipped :-) func (b *Bslack) skipMessageEvent(ev *slack.MessageEvent) bool { switch ev.SubType { case sChannelLeave, sChannelJoin: return b.GetBool(noSendJoinConfig) case sPinnedItem, sUnpinnedItem: return true case sChannelTopic, sChannelPurpose: // Skip the event if our bot/user account changed the topic/purpose if ev.User == b.si.User.ID { return true } } // Check for our callback ID hasOurCallbackID := false if len(ev.Blocks.BlockSet) == 1 { block, ok := ev.Blocks.BlockSet[0].(*slack.SectionBlock) hasOurCallbackID = ok && block.BlockID == "matterbridge_"+b.uuid } // Skip any messages that we made ourselves or from 'slackbot' (see #527). if ev.Username == sSlackBotUser || (b.rtm != nil && ev.Username == b.si.User.Name) || hasOurCallbackID { return true } if ev.SubMessage != nil { // It seems ev.SubMessage.Edited == nil when slack unfurls. // Do not forward these messages. See Github issue #266. if ev.SubMessage.ThreadTimestamp != ev.SubMessage.Timestamp && ev.SubMessage.Edited == nil { return true } // see hidden subtypes at https://api.slack.com/events/message // these messages are sent when we add a message to a thread #709 if ev.SubType == "message_replied" && ev.Hidden { return true } } if len(ev.Files) > 0 { return b.filesCached(ev.Files) } return false } func (b *Bslack) filesCached(files []slack.File) bool { for i := range files { if !b.fileCached(&files[i]) { return false } } return true } // handleMessageEvent handles the message events. Together with any called sub-methods, // this method implements the following event processing pipeline: // // 1. Check if the message should be ignored. // NOTE: This is not actually part of the method below but is done just before it // is called via the 'skipMessageEvent()' method. // 2. Populate the Matterbridge message that will be sent to the router based on the // received event and logic that is common to all events that are not skipped. // 3. Detect and handle any message that is "status" related (think join channel, etc.). // This might result in an early exit from the pipeline and passing of the // pre-populated message to the Matterbridge router. // 4. Handle the specific case of messages that edit existing messages depending on // configuration. // 5. Handle any attachments of the received event. // 6. Check that the Matterbridge message that we end up with after at the end of the // pipeline is valid before sending it to the Matterbridge router. func (b *Bslack) handleMessageEvent(ev *slack.MessageEvent) (*config.Message, error) { rmsg, err := b.populateReceivedMessage(ev) if err != nil { return nil, err } // Handle some message types early. if b.handleStatusEvent(ev, rmsg) { return rmsg, nil } b.handleAttachments(ev, rmsg) // Verify that we have the right information and the message // is well-formed before sending it out to the router. if len(ev.Files) == 0 && (rmsg.Text == "" || rmsg.Username == "") { if ev.BotID != "" { // This is probably a webhook we couldn't resolve. return nil, fmt.Errorf("message handling resulted in an empty bot message (probably an incoming webhook we couldn't resolve): %#v", ev) } if ev.SubMessage != nil { return nil, fmt.Errorf("message handling resulted in an empty message: %#v with submessage %#v", ev, ev.SubMessage) } return nil, fmt.Errorf("message handling resulted in an empty message: %#v", ev) } return rmsg, nil } func (b *Bslack) handleStatusEvent(ev *slack.MessageEvent, rmsg *config.Message) bool { switch ev.SubType { case sChannelJoined, sMemberJoined: // There's no further processing needed on channel events // so we return 'true'. return true case sChannelJoin, sChannelLeave: rmsg.Username = sSystemUser rmsg.Event = config.EventJoinLeave case sChannelTopic, sChannelPurpose: b.channels.populateChannels(false) rmsg.Event = config.EventTopicChange case sMessageChanged: rmsg.Text = ev.SubMessage.Text // handle deleted thread starting messages if ev.SubMessage.Text == "This message was deleted." { rmsg.Event = config.EventMsgDelete return true } case sMessageDeleted: rmsg.Text = config.EventMsgDelete rmsg.Event = config.EventMsgDelete rmsg.ID = ev.DeletedTimestamp // If a message is being deleted we do not need to process // the event any further so we return 'true'. return true case sMeMessage: rmsg.Event = config.EventUserAction } return false } func (b *Bslack) handleAttachments(ev *slack.MessageEvent, rmsg *config.Message) { // File comments are set by the system (because there is no username given). if ev.SubType == sFileComment { rmsg.Username = sSystemUser } // See if we have some text in the attachments. if rmsg.Text == "" { for _, attach := range ev.Attachments { if attach.Text != "" { if attach.Title != "" { rmsg.Text = attach.Title + "\n" } rmsg.Text += attach.Text } else { rmsg.Text = attach.Fallback } } } // Save the attachments, so that we can send them to other slack (compatible) bridges. if len(ev.Attachments) > 0 { rmsg.Extra[sSlackAttachment] = append(rmsg.Extra[sSlackAttachment], ev.Attachments) } // If we have files attached, download them (in memory) and put a pointer to it in msg.Extra. for i := range ev.Files { if err := b.handleDownloadFile(rmsg, &ev.Files[i], false); err != nil { b.Log.Errorf("Could not download incoming file: %#v", err) } } } func (b *Bslack) handleTypingEvent(ev *slack.UserTypingEvent) (*config.Message, error) { if ev.User == b.si.User.ID { return nil, ErrEventIgnored } channelInfo, err := b.channels.getChannelByID(ev.Channel) if err != nil { return nil, err } return &config.Message{ Channel: channelInfo.Name, Account: b.Account, Event: config.EventUserTyping, }, nil } // handleDownloadFile handles file download func (b *Bslack) handleDownloadFile(rmsg *config.Message, file *slack.File, retry bool) error { if b.fileCached(file) { return nil } // Check that the file is neither too large nor blacklisted. if err := helper.HandleDownloadSize(b.Log, rmsg, file.Name, int64(file.Size), b.General); err != nil { b.Log.WithError(err).Infof("Skipping download of incoming file.") return nil } // Actually download the file. data, err := helper.DownloadFileAuth(file.URLPrivateDownload, "Bearer "+b.GetString(tokenConfig)) if err != nil { return fmt.Errorf("download %s failed %#v", file.URLPrivateDownload, err) } if len(*data) != file.Size && !retry { b.Log.Debugf("Data size (%d) is not equal to size declared (%d)\n", len(*data), file.Size) time.Sleep(1 * time.Second) return b.handleDownloadFile(rmsg, file, true) } // If a comment is attached to the file(s) it is in the 'Text' field of the Slack messge event // and should be added as comment to only one of the files. We reset the 'Text' field to ensure // that the comment is not duplicated. comment := rmsg.Text rmsg.Text = "" helper.HandleDownloadData(b.Log, rmsg, file.Name, comment, file.URLPrivateDownload, data, b.General) return nil } // handleGetChannelMembers handles messages containing the GetChannelMembers event // Sends a message to the router containing *config.ChannelMembers func (b *Bslack) handleGetChannelMembers(rmsg *config.Message) bool { if rmsg.Event != config.EventGetChannelMembers { return false } cMembers := b.channels.getChannelMembers(b.users) extra := make(map[string][]interface{}) extra[config.EventGetChannelMembers] = append(extra[config.EventGetChannelMembers], cMembers) msg := config.Message{ Extra: extra, Event: config.EventGetChannelMembers, Account: b.Account, } b.Log.Debugf("sending msg to remote %#v", msg) b.Remote <- msg return true } // fileCached implements Matterbridge's caching logic for files // shared via Slack. // // We consider that a file was cached if its ID was added in the last minute or // it's name was registered in the last 10 seconds. This ensures that an // identically named file but with different content will be uploaded correctly // (the assumption is that such name collisions will not occur within the given // timeframes). func (b *Bslack) fileCached(file *slack.File) bool { if ts, ok := b.cache.Get("file" + file.ID); ok && time.Since(ts.(time.Time)) < time.Minute { return true } else if ts, ok = b.cache.Get("filename" + file.Name); ok && time.Since(ts.(time.Time)) < 10*time.Second { return true } return false }