A Matrix-bridge to allow you receiving and sending emails in Matrix. You can have multiple email accounts and write emails to one or multiple recipients.

git clone https://github.com/JojiiOfficial/Matrix-EmailBridge
cd Matrix-EmailBridge/main
go get -v -u
go build -o emailbridge
./emailbridge

The last command executes the bridge once to create the probably missing config file.
Continue: --> Configure

DockerHub: https://hub.docker.com/r/jojii/matrix_email_bridge

Run

docker pull jojii/matrix_email_bridge

to pull the image. Then create a container by running

docker run -d \
--restart unless-stopped \
-v `pwd`/data:/app/data \
--name email_bridge \
jojii/matrix_email_bridge

After configuring the bridge you have to run

docker start email_bridge

to start the docker container again.
Note: 'localhost' as 'matrixserver' (in cfg.json) wouldn't work because of dockers own network. You have to specify the internal IP address of the matrix-synapse server!

1. Create a bot user.
2. Get an access token to your Matrix-Server:

curl -XPOST -d '{"type":"m.login.password", "user":"@mailBotUsername:your-domain.com", "password":"mailbotPassword"}' "https://matrix.your-domain.com/_matrix/client/r0/login"

3. Adjust the config file (cfg.json) to make it work with your matrix server:

{
  "allowed_servers": [
    "your-base-domain.com"
  ],
  "defaultmailcheckinterval": 30,
  "htmldefault": false,
  "markdownenabledbydefault": true,
  "matrixaccesstoken": "access-token-from-step-3",
  "matrixserver": "matrix.full-matrix-server-domain.com",
  "matrixuserid": "@mailBotUsername:your-base-domain.com"
}

4. Invite your bot into a private room, it will join automatically.
   

If everything is set up correctly, you can bridge the room by typing !login. Then you just have to follow the instructions. The command !help shows a list with available commands.
Creating new private rooms with the bridge lets you add multiple email accounts.

Note: you should change the permissions of the cfg.json and data.db to 640 or 660 because they contain sensitive data.

• Receiving Email with IMAPs
• Use custom IMAPs Server and port
• Use the bridge with multiple email addresses
• Use the bridge with multiple user
• Ignore SSL certs if required
• Detailed error codes/logging
• Use custom mailbox instead of INBOX
• Sending emails (to one or multiple participants)
• Use markdown (automatically translated to HTML) for writing emails (optional)
• Viewing HTML messages (as good as your matrix-client supports html)
• Attaching files sent into the bridged room
• Emailaddress blocklist (Ignore emails from given emailaddress)

• System to send passwords not in plaintext
• Add more header (CC/Bcc)
• Update the installerscript