Add option to disable direct CDN uploads

config/bridge.go

@@ -51,6 +51,7 @@ type BridgeConfig struct {
 	DeletePortalOnChannelDelete bool `yaml:"delete_portal_on_channel_delete"`
 	DeleteGuildOnLeave          bool `yaml:"delete_guild_on_leave"`
 	FederateRooms               bool `yaml:"federate_rooms"`
+	UseDiscordCDNUpload         bool `yaml:"use_discord_cdn_upload"`
 
 	CacheMedia    string        `yaml:"cache_media"`
 	MediaPatterns MediaPatterns `yaml:"media_patterns"`

config/upgrade.go

@@ -55,6 +55,7 @@ func DoUpgrade(helper *up.Helper) {
 	helper.Copy(up.Bool, "bridge", "delete_portal_on_channel_delete")
 	helper.Copy(up.Bool, "bridge", "delete_guild_on_leave")
 	helper.Copy(up.Bool, "bridge", "federate_rooms")
+	helper.Copy(up.Bool, "bridge", "use_discord_cdn_upload")
 	helper.Copy(up.Bool, "bridge", "media_patterns", "enabled")
 	helper.Copy(up.Str, "bridge", "cache_media")
 	helper.Copy(up.Str|up.Null, "bridge", "media_patterns", "attachments")

example-config.yaml

@@ -145,6 +145,10 @@ bridge:
     # Whether or not created rooms should have federation enabled.
     # If false, created portal rooms will never be federated.
     federate_rooms: true
+    # Should the bridge upload media to the Discord CDN directly before sending the message when using a user token,
+    # like the official client does? The other option is sending the media in the message send request as a form part
+    # (which is always used by bots and webhooks).
+    use_discord_cdn_upload: true
     # Should mxc uris copied from Discord be cached?
     # This can be `never` to never cache, `unencrypted` to only cache unencrypted mxc uris, or `always` to cache everything.
     # If you have a media repo that generates non-unique mxc uris, you should set this to never.

portal.go

@@ -1496,7 +1496,7 @@ func (portal *Portal) handleMatrixMessage(sender *User, evt *event.Event) {
 			sendReq.Content, sendReq.AllowedMentions = portal.parseMatrixHTML(content)
 		}
 
-		if !isWebhookSend && sess.IsUser {
+		if portal.bridge.Config.Bridge.UseDiscordCDNUpload && !isWebhookSend && sess.IsUser {
 			att := &discordgo.MessageAttachment{
 				ID:          "0",
 				Filename:    filename,