Installation

pip install -r requirements.txt

Usage

• Run main.py to generate appservice.json

• Edit appservice.json:

{
    "as_token": "my-secret-as-token",
    "hs_token": "my-secret-hs-token",
    "user_id": "appservice-discord",
    "homeserver": "http://127.0.0.1:8008",
    "server_name": "localhost",
    "discord_token": "my-secret-discord-token",
    "port": 5000,
    "database": "/path/to/bridge.db"
}

as_token: The token sent by the appservice to the homeserver with events.

hs_token: The token sent by the homeserver to the appservice with events.

user_id: The username of the appservice user, it should match the sender_localpart in appservice.yaml.

homeserver: A URL including the port where the homeserver is listening on. The default should work in most cases where the homeserver is running locally and listening for non-TLS connections on port 8008.

server_name: The server's name, it is the part after : in MXIDs. As an example, kde.org is the server name in @testuser:kde.org.

discord_token: The Discord bot's token.

port: The port where bottle will listen for events.

database: Full path to the bridge's database.

Both as_token and hs_token MUST be the same as their values in appservice.yaml. Their value can be set to anything, refer to the spec.

• Create appservice.yaml and add it to your homeserver:

id: "discord"
url: "http://127.0.0.1:5000"
as_token: "my-secret-as-token"
hs_token: "my-secret-hs-token"
sender_localpart: "appservice-discord"
namespaces:
  users:
    - exclusive: true
      regex: "@_discord.*"
    - exclusive: true
      regex: "@appservice-discord"
  aliases:
    - exclusive: true
      regex: "#_discord.*"
  rooms: []

The following lines should be added to the homeserver configuration. The full path to appservice.yaml might be required:

• synapse:

# A list of application service config files to use
#
app_service_config_files:
  - appservice.yaml

• dendrite:

app_service_api:
  internal_api:
    # ...
  database:
    # ...
  config_files: [appservice.yaml]

A path can optionally be passed as the first argument to main.py. This path will be used as the base directory for the database and log file.

Eg. Running python3 main.py /path/to/my/dir will store the database and logs in /path/to/my/dir. $PWD is used by default if no path is specified.

After setting up the bridge, send a direct message to @appservice-discord:domain.tld containing the channel ID to be bridged (!bridge 123456).

This bridge is written with:

• bottle: Receiving events from the homeserver.
• urllib3: Sending requests, thread safety.
• websockets: Connecting to Discord. (Big thanks to an anonymous person "nesslersreagent" for figuring out the initial connection mess.)

NOTES

• A basic sqlite database is used for keeping track of bridged rooms.

• Discord users can be tagged only by mentioning the dummy Matrix user, which requires the client to send a formatted body containing HTML. Partial mentions are not used to avoid unreliable queries to the websocket.

• Logs are saved to the appservice.log file in $PWD or the specified directory.

• For avatars to show up on Discord, you must have a reverse proxy set up on your homeserver as the bridge does not specify the homeserver port when passing the avatar url.

• It is not possible to add "normal" Discord bot functionality like commands as this bridge does not use discord.py.

• Privileged Intents for members and presence must be enabled for your Discord bot.

• This Appservice might not work well for bridging a large number of rooms since it is mostly synchronous. However, it wouldn't take much effort to port it to asyncio and aiohttp if desired.