To enable users to do custom spam filtering based on score, it's helpful to render the actual spam score as a float in a separate header rather than as part of X-Spam-Status where it only appears in a comma separated list.
The antispam-plugin configuration is not ignoring deleted email (mail sent to a trash folder). This causes a big problem because if someone decides to "clean up" their Spam folder by deleting all of the emails, then sa-learn --ham is run on what is usually correctly caught spam messages. This causes big problems with the accuracy of the bayes scoring! It should really only be learning ham if someone drags the email to a non-Trash folder.
I ran "sa-learn --dbpath /home/user-data/mail/spamassassin --dump magic" before these changes and saw the nham counter increment with every message deleted from Spam. With this new config sa-learn --ham is not run when email is deleted from Spam so the bayes database is not incorrectly trained.
Create directory in $STORAGE_ROOT for bayes database.
Added --username arg to sa-learn as the user mail does not have permission to edit files in $STORAGE_ROOT. There is probably a better solution to this...
As the scripts keep growing, it's time to split them up to
keep them understandable.
This splits mail.sh into mail-postfix.sh, mail-dovecot.sh,
and mail-users.sh, which has all of the user database-related
configurations shared by Dovecot and Postfix. Also from
spamassassin.sh the core sieve configuration is moved into
mail-dovecot.sh and the virtual transport setting is moved
into mail-postfix.sh.
Also revising one of the sed scripts in mail-dovecot to
not insert a new additional # at the start of a line each
time the script is run.