Refactor gateway (#648)

* Decrease complexity of handleMessage, handleReceive, handleFiles
* Move handlers to handlers.go
* Split ignoreMessage up in ignoreTextEmpty, ignoreNicks and IgnoreTexts
* Add ignoreEvent
* Add testcase for ignoreTextEmpty, ignoreNicks, ignoreTexts and ignoreEvent

1 files changed, 98 insertions, 205 deletions

diff --git a/gateway/gateway.go b/gateway/gateway.go
index 0ee7a616..d6c6fcea 100644
--- a/gateway/gateway.go
+++ b/gateway/gateway.go
@@ -1,13 +1,6 @@
 package gateway
 
 import (
-	"bytes"
-	"crypto/sha1" //nolint:gosec
-	"fmt"
-	"io/ioutil"
-	"net/http"
-	"os"
-	"path/filepath"
 	"regexp"
 	"strings"
 	"time"
@@ -50,7 +43,9 @@ func New(cfg config.Gateway, r *Router) *Gateway {
 		Router: r, Bridges: make(map[string]*bridge.Bridge), Config: r.Config}
 	cache, _ := lru.New(5000)
 	gw.Messages = cache
-	gw.AddConfig(&cfg)
+	if err := gw.AddConfig(&cfg); err != nil {
+		flog.Errorf("AddConfig failed: %s", err)
+	}
 	return gw
 }
 
@@ -94,7 +89,9 @@ func (gw *Gateway) AddBridge(cfg *config.Bridge) error {
 func (gw *Gateway) AddConfig(cfg *config.Gateway) error {
 	gw.Name = cfg.Name
 	gw.MyConfig = cfg
-	gw.mapChannels()
+	if err := gw.mapChannels(); err != nil {
+		flog.Errorf("mapChannels() failed: %s", err)
+	}
 	for _, br := range append(gw.MyConfig.In, append(gw.MyConfig.InOut, gw.MyConfig.Out...)...) {
 		br := br //scopelint
 		err := gw.AddBridge(&br)
@@ -114,7 +111,9 @@ func (gw *Gateway) mapChannelsToBridge(br *bridge.Bridge) {
 }
 
 func (gw *Gateway) reconnectBridge(br *bridge.Bridge) {
-	br.Disconnect()
+	if err := br.Disconnect(); err != nil {
+		flog.Errorf("Disconnect() %s failed: %s", br.Account, err)
+	}
 	time.Sleep(time.Second * 5)
 RECONNECT:
 	flog.Infof("Reconnecting %s", br.Account)
@@ -125,7 +124,9 @@ RECONNECT:
 		goto RECONNECT
 	}
 	br.Joined = make(map[string]bool)
-	br.JoinChannels()
+	if err := br.JoinChannels(); err != nil {
+		flog.Errorf("JoinChannels() %s failed: %s", br.Account, err)
+	}
 }
 
 func (gw *Gateway) mapChannelConfig(cfg []config.Bridge, direction string) {
@@ -212,105 +213,55 @@ func (gw *Gateway) getDestMsgID(msgID string, dest *bridge.Bridge, channel confi
 	return ""
 }
 
-func (gw *Gateway) handleMessage(msg config.Message, dest *bridge.Bridge) []*BrMsgID {
-	var brMsgIDs []*BrMsgID
-
-	// if we have an attached file, or other info
-	if msg.Extra != nil {
-		if len(msg.Extra[config.EventFileFailureSize]) != 0 {
-			if msg.Text == "" {
-				return brMsgIDs
-			}
-		}
-	}
-
-	// Avatar downloads are only relevant for telegram and mattermost for now
-	if msg.Event == config.EventAvatarDownload {
-		if dest.Protocol != "mattermost" &&
-			dest.Protocol != "telegram" {
-			return brMsgIDs
-		}
-	}
-
-	// only relay join/part when configured
-	if msg.Event == config.EventJoinLeave && !dest.GetBool("ShowJoinPart") {
-		return brMsgIDs
-	}
-
-	// only relay topic change when used in some way on other side
-	if msg.Event == config.EventTopicChange &&
-		dest.GetBool("ShowTopicChange") &&
-		dest.GetBool("SyncTopic") {
-		return brMsgIDs
+// ignoreTextEmpty returns true if we need to ignore a message with an empty text.
+func (gw *Gateway) ignoreTextEmpty(msg *config.Message) bool {
+	if msg.Text != "" {
+		return false
 	}
-
-	// broadcast to every out channel (irc QUIT)
-	if msg.Channel == "" && msg.Event != config.EventJoinLeave {
-		flog.Debug("empty channel")
-		return brMsgIDs
+	if msg.Event == config.EventUserTyping {
+		return false
 	}
-
-	// Get the ID of the parent message in thread
-	var canonicalParentMsgID string
-	if msg.ParentID != "" && dest.GetBool("PreserveThreading") {
-		canonicalParentMsgID = gw.FindCanonicalMsgID(msg.Protocol, msg.ParentID)
+	// we have an attachment or actual bytes, do not ignore
+	if msg.Extra != nil &&
+		(msg.Extra["attachments"] != nil ||
+			len(msg.Extra["file"]) > 0 ||
+			len(msg.Extra[config.EventFileFailureSize]) > 0) {
+		return false
 	}
+	flog.Debugf("ignoring empty message %#v from %s", msg, msg.Account)
+	return true
+}
 
-	originchannel := msg.Channel
-	origmsg := msg
-	channels := gw.getDestChannel(&msg, *dest)
-	for _, channel := range channels {
-		// Only send the avatar download event to ourselves.
-		if msg.Event == config.EventAvatarDownload {
-			if channel.ID != getChannelID(origmsg) {
-				continue
-			}
-		} else {
-			// do not send to ourself for any other event
-			if channel.ID == getChannelID(origmsg) {
-				continue
-			}
-		}
-
-		// Too noisy to log like other events
-		if msg.Event != config.EventUserTyping {
-			flog.Debugf("=> Sending %#v from %s (%s) to %s (%s)", msg, msg.Account, originchannel, dest.Account, channel.Name)
-		}
-
-		msg.Channel = channel.Name
-		msg.Avatar = gw.modifyAvatar(origmsg, dest)
-		msg.Username = gw.modifyUsername(origmsg, dest)
-
-		msg.ID = gw.getDestMsgID(origmsg.Protocol+" "+origmsg.ID, dest, channel)
-
-		// for api we need originchannel as channel
-		if dest.Protocol == apiProtocol {
-			msg.Channel = originchannel
-		}
-
-		msg.ParentID = gw.getDestMsgID(origmsg.Protocol+" "+canonicalParentMsgID, dest, channel)
-		if msg.ParentID == "" {
-			msg.ParentID = canonicalParentMsgID
-		}
-
-		// if we are using mattermost plugin account, send messages to MattermostPlugin channel
-		// that can be picked up by the mattermost matterbridge plugin
-		if dest.Account == "mattermost.plugin" {
-			gw.Router.MattermostPlugin <- msg
+// ignoreTexts returns true if msg.Text matches any of the input regexes.
+func (gw *Gateway) ignoreTexts(msg *config.Message, input []string) bool {
+	for _, entry := range input {
+		if entry == "" {
+			continue
 		}
-
-		mID, err := dest.Send(msg)
+		// TODO do not compile regexps everytime
+		re, err := regexp.Compile(entry)
 		if err != nil {
-			flog.Error(err)
+			flog.Errorf("incorrect regexp %s for %s", entry, msg.Account)
+			continue
+		}
+		if re.MatchString(msg.Text) {
+			flog.Debugf("matching %s. ignoring %s from %s", entry, msg.Text, msg.Account)
+			return true
 		}
+	}
+	return false
+}
 
-		// append the message ID (mID) from this bridge (dest) to our brMsgIDs slice
-		if mID != "" {
-			flog.Debugf("mID %s: %s", dest.Account, mID)
-			brMsgIDs = append(brMsgIDs, &BrMsgID{dest, dest.Protocol + " " + mID, channel.ID})
+// ignoreNicks returns true if msg.Username matches any of the input regexes.
+func (gw *Gateway) ignoreNicks(msg *config.Message, input []string) bool {
+	// is the username in IgnoreNicks field
+	for _, entry := range input {
+		if msg.Username == entry {
+			flog.Debugf("ignoring %s from %s", msg.Username, msg.Account)
+			return true
 		}
 	}
-	return brMsgIDs
+	return false
 }
 
 func (gw *Gateway) ignoreMessage(msg *config.Message) bool {
@@ -319,45 +270,12 @@ func (gw *Gateway) ignoreMessage(msg *config.Message) bool {
 		return true
 	}
 
-	// check if we need to ignore a empty message
-	if msg.Text == "" {
-		if msg.Event == config.EventUserTyping {
-			return false
-		}
-		// we have an attachment or actual bytes, do not ignore
-		if msg.Extra != nil &&
-			(msg.Extra["attachments"] != nil ||
-				len(msg.Extra["file"]) > 0 ||
-				len(msg.Extra[config.EventFileFailureSize]) > 0) {
-			return false
-		}
-		flog.Debugf("ignoring empty message %#v from %s", msg, msg.Account)
+	igNicks := strings.Fields(gw.Bridges[msg.Account].GetString("IgnoreNicks"))
+	igMessages := strings.Fields(gw.Bridges[msg.Account].GetString("IgnoreMessages"))
+	if gw.ignoreTextEmpty(msg) || gw.ignoreNicks(msg, igNicks) || gw.ignoreTexts(msg, igMessages) {
 		return true
 	}
 
-	// is the username in IgnoreNicks field
-	for _, entry := range strings.Fields(gw.Bridges[msg.Account].GetString("IgnoreNicks")) {
-		if msg.Username == entry {
-			flog.Debugf("ignoring %s from %s", msg.Username, msg.Account)
-			return true
-		}
-	}
-
-	// does the message match regex in IgnoreMessages field
-	// TODO do not compile regexps everytime
-	for _, entry := range strings.Fields(gw.Bridges[msg.Account].GetString("IgnoreMessages")) {
-		if entry != "" {
-			re, err := regexp.Compile(entry)
-			if err != nil {
-				flog.Errorf("incorrect regexp %s for %s", entry, msg.Account)
-				continue
-			}
-			if re.MatchString(msg.Text) {
-				flog.Debugf("matching %s. ignoring %s from %s", entry, msg.Text, msg.Account)
-				return true
-			}
-		}
-	}
 	return false
 }
 
@@ -438,86 +356,61 @@ func (gw *Gateway) modifyMessage(msg *config.Message) {
 	}
 }
 
-// handleFiles uploads or places all files on the given msg to the MediaServer and
-// adds the new URL of the file on the MediaServer onto the given msg.
-func (gw *Gateway) handleFiles(msg *config.Message) {
-	reg := regexp.MustCompile("[^a-zA-Z0-9]+")
-
-	// If we don't have a attachfield or we don't have a mediaserver configured return
-	if msg.Extra == nil ||
-		(gw.BridgeValues().General.MediaServerUpload == "" &&
-			gw.BridgeValues().General.MediaDownloadPath == "") {
-		return
-	}
-
-	// If we don't have files, nothing to upload.
-	if len(msg.Extra["file"]) == 0 {
-		return
+// SendMessage sends a message (with specified parentID) to the channel on the selected destination bridge.
+// returns a message id and error.
+func (gw *Gateway) SendMessage(origmsg config.Message, dest *bridge.Bridge, channel config.ChannelInfo, canonicalParentMsgID string) (string, error) {
+	msg := origmsg
+	// Only send the avatar download event to ourselves.
+	if msg.Event == config.EventAvatarDownload {
+		if channel.ID != getChannelID(origmsg) {
+			return "", nil
+		}
+	} else {
+		// do not send to ourself for any other event
+		if channel.ID == getChannelID(origmsg) {
+			return "", nil
+		}
 	}
 
-	client := &http.Client{
-		Timeout: time.Second * 5,
+	// Too noisy to log like other events
+	if msg.Event != config.EventUserTyping {
+		flog.Debugf("=> Sending %#v from %s (%s) to %s (%s)", msg, msg.Account, origmsg.Channel, dest.Account, channel.Name)
 	}
 
-	for i, f := range msg.Extra["file"] {
-		fi := f.(config.FileInfo)
-		ext := filepath.Ext(fi.Name)
-		fi.Name = fi.Name[0 : len(fi.Name)-len(ext)]
-		fi.Name = reg.ReplaceAllString(fi.Name, "_")
-		fi.Name += ext
-
-		sha1sum := fmt.Sprintf("%x", sha1.Sum(*fi.Data))[:8] //nolint:gosec
-
-		if gw.BridgeValues().General.MediaServerUpload != "" {
-			// Use MediaServerUpload. Upload using a PUT HTTP request and basicauth.
-
-			url := gw.BridgeValues().General.MediaServerUpload + "/" + sha1sum + "/" + fi.Name
-
-			req, err := http.NewRequest("PUT", url, bytes.NewReader(*fi.Data))
-			if err != nil {
-				flog.Errorf("mediaserver upload failed, could not create request: %#v", err)
-				continue
-			}
-
-			flog.Debugf("mediaserver upload url: %s", url)
-
-			req.Header.Set("Content-Type", "binary/octet-stream")
-			_, err = client.Do(req)
-			if err != nil {
-				flog.Errorf("mediaserver upload failed, could not Do request: %#v", err)
-				continue
-			}
-		} else {
-			// Use MediaServerPath. Place the file on the current filesystem.
+	msg.Channel = channel.Name
+	msg.Avatar = gw.modifyAvatar(origmsg, dest)
+	msg.Username = gw.modifyUsername(origmsg, dest)
 
-			dir := gw.BridgeValues().General.MediaDownloadPath + "/" + sha1sum
-			err := os.Mkdir(dir, os.ModePerm)
-			if err != nil && !os.IsExist(err) {
-				flog.Errorf("mediaserver path failed, could not mkdir: %s %#v", err, err)
-				continue
-			}
+	msg.ID = gw.getDestMsgID(origmsg.Protocol+" "+origmsg.ID, dest, channel)
 
-			path := dir + "/" + fi.Name
-			flog.Debugf("mediaserver path placing file: %s", path)
+	// for api we need originchannel as channel
+	if dest.Protocol == apiProtocol {
+		msg.Channel = origmsg.Channel
+	}
 
-			err = ioutil.WriteFile(path, *fi.Data, os.ModePerm)
-			if err != nil {
-				flog.Errorf("mediaserver path failed, could not writefile: %s %#v", err, err)
-				continue
-			}
-		}
+	msg.ParentID = gw.getDestMsgID(origmsg.Protocol+" "+canonicalParentMsgID, dest, channel)
+	if msg.ParentID == "" {
+		msg.ParentID = canonicalParentMsgID
+	}
 
-		// Download URL.
-		durl := gw.BridgeValues().General.MediaServerDownload + "/" + sha1sum + "/" + fi.Name
+	// if we are using mattermost plugin account, send messages to MattermostPlugin channel
+	// that can be picked up by the mattermost matterbridge plugin
+	if dest.Account == "mattermost.plugin" {
+		gw.Router.MattermostPlugin <- msg
+	}
 
-		flog.Debugf("mediaserver download URL = %s", durl)
+	mID, err := dest.Send(msg)
+	if err != nil {
+		return mID, err
+	}
 
-		// We uploaded/placed the file successfully. Add the SHA and URL.
-		extra := msg.Extra["file"][i].(config.FileInfo)
-		extra.URL = durl
-		extra.SHA = sha1sum
-		msg.Extra["file"][i] = extra
+	// append the message ID (mID) from this bridge (dest) to our brMsgIDs slice
+	if mID != "" {
+		flog.Debugf("mID %s: %s", dest.Account, mID)
+		return mID, nil
+		//brMsgIDs = append(brMsgIDs, &BrMsgID{dest, dest.Protocol + " " + mID, channel.ID})
 	}
+	return "", nil
 }
 
 func (gw *Gateway) validGatewayDest(msg *config.Message) bool {