gpg-lacre/doc/adv-filt.md

Advanced Filter

Postfix Filters

There are two types of Postfix mail filters: Simple Filters and Advanced Filters. Simple Filters are executed for each incoming email as a new process, which may turn out to be expensive in terms of resources. Advanced Filters work as a mail-processing proxies.

For detailed documentation, see FILTER README.

Installation

Just use the following command to install dependencies:

pip install -r requirements.txt

Configuration

Lacre Advanced Filter, also known as daemon, is configured in the [daemon] section of configuration file. Two obligatory parameters to be defined there are:

• host -- IP address or a host name;
• port -- TCP port Lacre should listen on.

The other very important section is [relay], which by default uses Simple Filter destination. It has to be adjusted for Advanced Filter to work, setting port to 10026.

Command to spawn a Lacre daemon process is:

LACRE_CONFIG=/etc/lacre.conf PYTHONPATH=... python -m lacre.daemon

Two environment variables used here are:

• LACRE_CONFIG (not mandatory) -- path to Lacre configuration, unless it's kept in default location (/etc/lacre.conf).
• PYTHONPATH (not mandatory) -- location of Lacre modules. You can place them below your Python's site-packages to be reachable by any other Python software.