Chatmail services optimized for Delta Chat apps

This repository helps to setup a ready-to-use chatmail server comprised of a minimal setup of the battle-tested postfix smtp and dovecot imap services.

The setup is designed and optimized for providing chatmail accounts for use by Delta Chat apps.

Chatmail accounts are automatically created by a first login, after which the initially specified password is required for using them.

Deploying your own chatmail server

We subsequently use CHATMAIL_DOMAIN as a placeholder for your fully qualified DNS domain name (FQDN), for example chat.example.org.

1. Setup DNS A and AAAA records for your CHATMAIL_DOMAIN. Verify that DNS is set and SSH root login works:

        ssh root@CHATMAIL_DOMAIN 
   

2. Install the cmdeploy command in a virtualenv and activate it

    scripts/initenv.sh
    . venv/bin/activate
   

3. Create chatmail configuration file chatmail.ini:

    cmdeploy init CHATMAIL_DOMAIN
   

4. Deploy to the remote chatmail server:

    cmdeploy run 
   

5. To output a DNS zone file from which you can transfer DNS records to your DNS provider:

    cmdeploy dns
   

6. To check status of your remotely running chatmail service:

    cmdeploy status
   

7. To test your chatmail service:

    cmdeploy test
   

8. To benchmark your chatmail service:

    cmdeploy bench
   

Refining the web pages

    cmdeploy webdev 

This starts a local live development cycle for chatmail Web pages:

• uses the www/src/page-layout.html file for producing static HTML pages from www/src/*.md files

• continously builds the web presence reading files from www/src directory and generating html files and copying assets to the www/build directory.

• Starts a browser window automatically where you can "refresh" as needed.

Home page and getting started for users

cmdeploy run sets up mail services, and also creates default static Web pages and deploys them:

• a default index.html along with a QR code that users can click to create accounts on your chatmail provider,

• a default info.html that is linked from the home page,

• a default policy.html that is linked from the home page.

All .html files are generated by the according markdown .md file in the www/src directory.

Ports

Postfix listens on ports 25 (smtp) and 587 (submission) and 465 (submissions). Dovecot listens on ports 143(imap) and 993 (imaps).

Delta Chat will, however, discover all ports and configurations automatically by reading the autoconfig.xml file from the chatmail instance.

Emergency Commands to disable automatic account creation

If you need to stop account creation, e.g. because some script is wildly creating accounts, run:

touch /etc/chatmail-nocreate

While this file is present, account creation will be blocked.

Running tests and benchmarks (offline and online)

1. Set CHATMAIL_SSH so that ssh root@$CHATMAIL_SSH allows to login to the chatmail instance server.

2. To run local and online tests:

   scripts/test.sh

3. To run benchmarks against your chatmail instance:

   scripts/bench.sh

Development Background for chatmail instances

This repository drives the development of "chatmail instances", comprised of minimal setups of

• postfix smtp server
• dovecot imap server

as well as two custom services that are integrated with these two:

• chatmaild/src/chatmaild/doveauth.py implements create-on-login account creation semantics and is used by Dovecot during login authentication and by Postfix which in turn uses Dovecot SASL to authenticate users to send mails for them.

• chatmaild/src/chatmaild/filtermail.py prevents unencrypted e-mail from leaving the chatmail instance and is integrated into postfix's outbound mail pipelines.