2025-10-08 10:33:26 +13:00

115 lines
4.5 KiB
Bash

#!/bin/bash
# Docs - Config:
# https://www.fetchmail.info/fetchmail-man.html#the-run-control-file
# Docs - CLI:
# https://www.fetchmail.info/fetchmail-man.html#general-operation
# https://www.fetchmail.info/fetchmail-man.html#daemon-mode
function _setup_fetchmail() {
if [[ ${ENABLE_FETCHMAIL} -eq 1 ]]; then
_log 'trace' 'Enabling and configuring Fetchmail'
local CONFIGURATION FETCHMAILRC
CONFIGURATION='/tmp/docker-mailserver/fetchmail.cf'
FETCHMAILRC='/etc/fetchmailrc'
# Create `/etc/fetchmailrc` with default global config, optionally appending user-provided config:
if [[ -f ${CONFIGURATION} ]]; then
cat /etc/fetchmailrc_general "${CONFIGURATION}" >"${FETCHMAILRC}"
else
cat /etc/fetchmailrc_general >"${FETCHMAILRC}"
fi
chmod 700 "${FETCHMAILRC}"
chown fetchmail:root "${FETCHMAILRC}"
else
_log 'debug' 'Fetchmail is disabled'
fi
}
# NOTE: This feature is only actually relevant for entries polling via IMAP (to support leveraging the "IMAP IDLE" extension):
# - With either the `--idle` CLI or `idle` config option present
# - With a constraint on one fetchmail instance per server polled (and only for a single mailbox folder to monitor from that poll entry)
# - Reference: https://otremba.net/wiki/Fetchmail_(Debian)#Immediate_Download_via_IMAP_IDLE
function _setup_fetchmail_parallel() {
if [[ ${FETCHMAIL_PARALLEL} -eq 1 ]]; then
_log 'trace' 'Enabling and configuring Fetchmail parallel'
mkdir /etc/fetchmailrc.d/
# Extract the content of `/etc/fetchmailrc` into:
# - Individual `/etc/fetchmailrc.d/fetchmail-*.rc` files, one per server (`poll` entries)
# - Global config options temporarily to `/etc/fetchmailrc.d/defaults`, which is prepended to each `fetchmail-*.rc` file
function _fetchmailrc_split() {
local FETCHMAILRC='/etc/fetchmailrc'
local FETCHMAILRCD='/etc/fetchmailrc.d'
local DEFAULT_FILE="${FETCHMAILRCD}/defaults"
if [[ ! -r ${FETCHMAILRC} ]]; then
_log 'warn' "File '${FETCHMAILRC}' not found"
return 1
fi
if [[ ! -d ${FETCHMAILRCD} ]]; then
if ! mkdir "${FETCHMAILRCD}"; then
_log 'warn' "Unable to create folder '${FETCHMAILRCD}'"
return 1
fi
fi
# Scan through the config:
# 1. Extract the global fetchmail config lines (before any poll entry is configured).
# 2. Once a poll entry line is found, create a new config with the global config and append the poll entry config.
# 3. Repeat step 2 when another poll entry is found, until reaching the end of `/etc/fetchmailrc`.
local COUNTER=0 SERVER=0
while read -r LINE; do
if [[ ${LINE} =~ poll ]]; then
# Signal that global config has been captured (only remaining poll entry configs needs to be parsed):
SERVER=1
# Create a new fetchmail config for this poll entry:
COUNTER=$(( COUNTER + 1 ))
cat "${DEFAULT_FILE}" >"${FETCHMAILRCD}/fetchmail-${COUNTER}.rc"
echo "${LINE}" >>"${FETCHMAILRCD}/fetchmail-${COUNTER}.rc"
elif [[ ${SERVER} -eq 0 ]]; then
# Until the first poll entry is encountered, all lines are captured as global config:
echo "${LINE}" >>"${DEFAULT_FILE}"
else
# Otherwise until a new poll entry is encountered, all lines are captured for the current poll config:
echo "${LINE}" >>"${FETCHMAILRCD}/fetchmail-${COUNTER}.rc"
fi
done < <(_get_valid_lines_from_file "${FETCHMAILRC}")
rm "${DEFAULT_FILE}"
}
_fetchmailrc_split
# Create supervisord service files for each instance:
# `--idfile` is intended for supporting POP3 with UIDL cache (requires either `--uidl` for CLI, or `uidl` setting in config)
local COUNTER=0
for RC in /etc/fetchmailrc.d/fetchmail-*.rc; do
COUNTER=$(( COUNTER + 1 ))
cat >"/etc/supervisor/conf.d/fetchmail-${COUNTER}.conf" << EOF
[program:fetchmail-${COUNTER}]
startsecs=0
autostart=false
autorestart=true
stdout_logfile=/var/log/supervisor/%(program_name)s.log
stderr_logfile=/var/log/supervisor/%(program_name)s.log
user=fetchmail
command=/usr/bin/fetchmail --fetchmailrc ${RC} --verbose --nodetach --daemon %(ENV_FETCHMAIL_POLL)s --idfile /var/lib/fetchmail/.fetchmail-UIDL-cache --pidfile /var/run/fetchmail/%(program_name)s.pid
EOF
chmod 700 "${RC}"
chown fetchmail:root "${RC}"
done
supervisorctl reread
supervisorctl update
else
_log 'debug' 'Fetchmail parallel is disabled'
fi
}