#!/bin/bash

set -eu -o pipefail

# this config matches the docker log-file configuration
# logrotate ignores daily/monthly etc with size directive
readonly logrotate_template=$(cat <<"EOF"
    "$LOG_VOLUME/*" "$LOG_VOLUME/*/*" "$LOG_VOLUME/*/*/*" {
        missingok
        rotate 4
        size 5M
        nocompress
        copytruncate
        notifempty
        create
        su
        maxage 7
    }
EOF
)

readonly containers=$(docker ps -qa)

for container in $containers; do
    echo "Cleaning up $container"

    if tmpdir=$(docker inspect --format='{{index .Volumes "/tmp"}}' $container); then
        echo -e "\tRemoving old files from $tmpdir"

        if [[ $tmpdir == /home/yellowtent/data/docker/volumes/* ]]; then
            find $tmpdir -mtime +10 -exec rm -rf {} + # 10 days max. note we cannot use atime because this is not a tmpfs
        else
            echo -e "\tInternal error in script. /tmp is mounted at unexpected location $tmpdir"
        fi
    fi

    if logdir=$(docker inspect --format='{{index .Volumes "/var/log"}}' $container); then
        echo -e "\tLogrotate files under $logdir"

        logrotate_config=$(mktemp)
        { echo "$logrotate_template" | LOG_VOLUME="$logdir" envsubst; } > "${logrotate_config}"

        logrotate "${logrotate_config}" # -f is not required since we are size based

        find "${logdir}" -mindepth 3 -maxdepth 3 -type d -exec rm -rf {}  + # since we logrotate only till depth 3

        rm "${logrotate_config}"
    fi
done