Optionally suppress URL embeds for Discord

bridge/discord/discord.go

@@ -36,6 +36,9 @@ type Bdiscord struct {
 	userMemberMap map[string]*discordgo.Member
 	nickMemberMap map[string]*discordgo.Member
 
+	noEmbedPartUrls bool
+	noEmbedUrls     bool
+
 	// Webhook specific logic
 	useAutoWebhooks bool
 	transmitter     *transmitter.Transmitter
@@ -57,6 +60,12 @@ func New(cfg *bridge.Config) bridge.Bridger {
 	b.nickMemberMap = make(map[string]*discordgo.Member)
 	b.channelInfoMap = make(map[string]*config.ChannelInfo)
 
+	b.noEmbedPartUrls = b.GetBool("NoEmbedPartUrls")
+	b.noEmbedUrls = b.GetBool("NoEmbedUrls")
+	if b.noEmbedPartUrls && b.noEmbedUrls {
+		b.Log.Info("NoEmbedUrls supersedes NoEmbedPartUrls when both are specified.")
+	}
+
 	b.useAutoWebhooks = b.GetBool("AutoWebhooks")
 	if b.useAutoWebhooks {
 		b.Log.Debug("Using automatic webhooks")
@@ -269,6 +278,10 @@ func (b *Bdiscord) Send(msg config.Message) (string, error) {
 		msg.Text = "_" + msg.Text + "_"
 	}
 
+	if b.noEmbedUrls || (msg.Event == config.EventJoinLeave && b.noEmbedPartUrls) {
+		disableEmbedUrls(&msg.Text)
+	}
+
 	// Handle prefix hint for unthreaded messages.
 	if msg.ParentNotFound() {
 		msg.ParentID = ""

bridge/discord/helpers.go

@@ -233,6 +233,11 @@ func (b *Bdiscord) splitURL(url string) (string, string, bool) {
 	return webhookURLSplit[webhookIdxID], webhookURLSplit[webhookIdxToken], true
 }
 
+func disableEmbedUrls(msg *string) {
+	regex := regexp.MustCompile(`(\w+://\S+)`)
+	*msg = regex.ReplaceAllString(*msg, "<$1>")
+}
+
 func enumerateUsernames(s string) []string {
 	onlySpace := true
 	for _, r := range s {

matterbridge.toml.sample

@@ -939,6 +939,15 @@ IgnoreNicks=""
 #   IgnoreMessages="^~~ badword"
 IgnoreMessages=""
 
+# Prevent URL embeds by encasing URLs in <> angle brackets.
+# Useful if trolls are a problem on the other end of your bridge.
+NoEmbedUrls=false
+
+# Prevent URL embeds in part/quit messages by encasing URLs in <> angle brackets.
+# Useful if trolls spam in their quit messages or you're tired of seeing embeds for
+# IRC client homepages.
+NoEmbedPartUrls=false
+
 # ReplaceMessages replaces substrings of messages in outgoing messages.
 # Regular expressions are supported.
 #