Mumble Discord Bridge is an open source Go application to bridge the audio and chat between Mumble and Discord.
It was built with the idea that people can continue to use the voice application of their choice.
Mumble Discord Bridge can be hosted on any server or computer and ships in a Docker container for convenience.
For those looking for SaaS solution take a look at PatchCord.io. PatchCord offers a free tier for those who want to try out Mumble Discord Bridge.
Several configuration variables are required to run the bridge. All variables can be set using command line flags or in the environment. The variable can also be specified in an .env file located in the working directory. See the help documentation for all the options
./mumble-discord-bridge --helpThe bridge can be run with the follow modes:
auto
The bot starts up but does not connect audio channels immediately. It can be either manually linked (see below) or will join the voice channels when there's at least one person on each side.
The audio bridge will leave both voice channels once there is no one on either end
manual
The bot starts up but does not connect immediately. It will join the voice channels when issued the link command via chat and will leave with the unlink command
constant (default)
The bridge starts up and immediately connects to both Discord and Mumble voice channels. It can not be controlled in this mode and quits when the program is stopped
In "auto" or "manual" modes, the bridge can be controlled in Discord with the following commands:
!COMMAND auto
Toggle between manual and auto mode
!COMMAND link
(Discord Only) Commands the bridge to join the Discord channel the user is in and the Mumble server
!COMMAND unlink
(Discord Only) Commands the bridge to leave the Discord channel the user is in and the Mumble server
!COMMAND refresh
(Discord Only) Commands the bridge to unlink, then link again.
There are additional commands that can be called from either Mumble or Discord.
!COMMAND help
Print help text
!COMMAND Version
Print the version
!Command restart
Restart the bridge
!COMMAND list
List all connected users in both Mumble and Discord.
A Discord Bot is required to authenticate this application with Discord. The guide below provides information on how to create a Discord bot.
Individual Discord servers need to invite the bot before it can connect.
The bot requires the following permissions:
- View Channels
- See Messages
- Read Message History
- Voice Channel Connect
- Voice Channel Speak
- Voice Channel Use Voice Activity
Permission integer 36768768.
Discord GID is a unique ID linked to one Discord Server, also called Guild. CID is similarly a unique ID for a Discord Channel. To find these you need to set Discord into developer Mode.
Instructions to enable Discord Developer Mode
Then you can get the GID by right-clicking your server and selecting Copy-ID. Similarly the CID can be found right clicking the voice channel and selecting Copy ID.
Optionally you can specify a client certificate for mumble Mumble Certificates If you don't have a client certificate, you can generate one with this command:
openssl req -x509 -nodes -days 3650 -newkey rsa:2048 -keyout cert.pem -out cert.pem -subj "/CN=mumble-discord-bridge"Prebuilt binaries are available. The binaries require the opus code runtime library to be installed.
# Ubuntu
sudo apt install libopus0curl -s https://api.github.com/repos/stieneee/mumble-discord-bridge/releases/latest | grep "mumble-discord-bridge" | grep "browser_download_url" | cut -d '"' -f 4 | wget -qi -This project is built and distributed in a docker container.
A sample docker command can be copied from below.
This service command will always attempt to restart the service due to the --restart=always flag even when the server is restarted.
For testing purposes it may be best to remove the restart flag.
Replace the environment variables with variable for the desired mumble server, discord bot and discord server/channel.
# Sample for testing
docker docker run -e MUMBLE_ADDRESS=example.com -e MUMBLE_PASSWORD=optional -e DISCORD_TOKEN=TOKEN -e DISCORD_GID=GID -e DISCORD_CID=CID stieneee/mumble-discord-bridge
# Run as a service
docker docker run -e MUMBLE_ADDRESS=example.com -e MUMBLE_PASSWORD=optional -e DISCORD_TOKEN=TOKEN -e DISCORD_GID=GID -e DISCORD_CID=CID --restart=always --name=mumble-discord-bridge -d stieneee/mumble-discord-bridge
# Stop the service
docker stop mumble-discord-bridge && docker rm mumble-discord-bridgeThe following options can be set using environment variables or with command line options.
Note boolean vales are flags when set via command line. example -mumble-insecure -mumble-disable-text not -mumble-insecure true -mumble-disable-text true.
| Environment Variable | CLI | Type | Default | Description |
|---|---|---|---|---|
| CHAT_BRIDGE | -chat-bridge | flag | false | enable text chat bridge |
| COMMAND | -command | string | "mumble-discord" | command phrase '!mumble-discord help' to control the bridge via text channels |
| COMMAND_MODE | -command | string | "both" | [both, mumble, discord, none] determine which side of the bridge will respond to commands |
| DEBUG_LEVEL | -debug-level | int | 1 | discord debug level |
| DISCORD_CID | -discord-cid | string | "" | discord cid, required |
| DISCORD_DISABLE_BOT_STATUS | -discord-disable-bot-status | flag | false | disable updating bot status |
| DISCORD_TEXT_MODE | -discord-text-mode | string | "channel" | disable sending direct messages to discord |
| DISCORD_GID | -discord-gid | string | "" | discord gid, required |
| DISCORD_TOKEN | -discord-token | string | "" | discord bot token, required |
| MODE | -mode | string | "constant" | [constant, manual, auto] determine which mode the bridge starts in |
| MUMBLE_ADDRESS | -mumble-address | string | "" | mumble server address, example example.com, required |
| MUMBLE_CERTIFICATE | -mumble-certificate | string | "" | client certificate to use when connecting to the Mumble server |
| MUMBLE_CHANNEL | -mumble-channel | string | "" | mumble channel to start in, using '/' to separate nested channels, optional |
| MUMBLE_DISABLE_TEXT | -mumble-disable-text | flag | false | disable sending text to mumble |
| MUMBLE_INSECURE | -mumble-insecure | flag | false | mumble insecure, ignore ssl certificates issues |
| MUMBLE_PASSWORD | -mumble-password | string | "" | mumble password |
| MUMBLE_PORT | -mumble-port | int | 64738 | mumble port |
| MUMBLE_USERNAME | -mumble-username | string | "Discord" | mumble username |
| MUMBLE_BOT | -mumble-bot | flag | false | exclude bot from mumble user count, optional, requires mumble v1.5 or later |
| PROMETHEUS_ENABLE | -prometheus-enable | flag | false | enable prometheus metrics |
| PROMETHEUS_PORT | -prometheus-port | int | 9559 | prometheus metrics port |
| TO_DISCORD_BUFFER | -to-discord-buffer | int | 50 | jitter buffer from Mumble to Discord to absorb timing issues related to network, OS and hardware quality. (Increments of 10ms) |
| TO_MUMBLE_BUFFER | -to-mumble-buffer | int | 50 | jitter buffer from Discord to Mumble to absorb timing issues related to network, OS and hardware quality. (Increments of 10ms) |
To ensure compatibility please edit your murmur configuration and add the following
opusthreshold=0This ensures all packets are opus encoded and should not cause any compatibility issues if your users are using up to date clients.
The chat bridge feature will relay chat messages between mumble and discord channels. To enable the feature the MUMBLE_DISABLE_TEXT must be false and DISCORD_TEXT_MODE must be set to "channel" (the default state). Finally the CHAT_BRIDGE variable must be set to true.
This project requires Golang to build from source. A simple go build command is all that is needed. Ensure the opus library is installed.
go install github.com/goreleaser/goreleaser@latest
goreleaser build --skip-validate --rm-dist --single-targetOpenBSD users should consider compiling a custom kernel to use 1000 ticks for the best possible performance. See issue 20 for the latest discussion about this topic.
The bridge implements simple jitter buffers that attempt to compensate for network, OS and hardware related jitter. These jitter buffers are configurable in both directions. A jitter buffer will slightly the delay the transmission of audio in order to have audio packets buffered for the next time step. The Mumble client itself includes a jitter buffer for similar reasons. A default jitter of 50ms should be adequate for most scenarios. A warning will be logged if short burst or audio are seen. A single warning can be ignored multiple warnings in short time spans would suggest the need for a larger jitter buffer.
The bridge can be started with a Prometheus metrics endpoint enabled. The example folder contains the a docker-compose file that will spawn the bridge, Prometheus and Grafana configured to serve a single a pre-configured dashboard.
The endpoint exposes /live and /ready for use with Kubernetes.
Currently there is an issue opening the discord voice channel. It is a known issue with a dependency of this project.
Audio leveling from Discord needs to be improved.
Delays in connecting to Mumble (such as from external authentication plugins) may result in extra error messages on initial connection.
There is an issue seen with Mumble-Server (murmur) 1.3.0 in which the bridge will loose the ability to send messages client after prolonged periods of connectivity. This issue has been appears to be resolved by murmur 1.3.4.
DISCORD_DISABLE_TEXT has been replaced with DISCORD_TEXT_MODE. As a result the default behavior has been change from direct messages to users "user" to "channel".
DISCORD_COMMAND has been replace with COMMAND and COMMAND_MODE. The feature now supports both mumble and discord. The default command phrase remains "!mumble-discord".
Distributed under the MIT License. See LICENSE for more information.
Issues and PRs are welcome and encouraged. Please consider opening an issue to discuss features and ideas.
The project would not have been possible without: