_cron_sweep

#! /bin/bash
#
# !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
# ! FILE IS CONTROLLED BY ANSIBLE, DO NOT CHANGE, OR ELSE YOUR CHANGES WILL BE EVENTUALLY LOST !
# !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
#
# Disk Space Management
#
# Called from download scripts when space is low.
# Can also be started directly from a shell prompt or cron job.
#
# See "../etc/sweep_rules" for the house-keeping rules, and some more docs.
#

set -e
source /usr/local/lib/pmb/common.sh

MAX_REQUEST_GiB=99
RESERVED_GiB=10
PROTECTED="xfer=+0 OR prio=3 OR is_ignored=y"

INTERACTIVE=""
INFO="log INFO:"
DRY=""
simulate=false


# Option parsing
while test "${1:0:1}" = '-'; do
    case "$1" in
        -n)
            shift
            DRY=echo
            simulate=true
            ;;
        --yes)
            shift
            INTERACTIVE="--yes"
            ;;
        --cron)
            shift
            INTERACTIVE="--cron --yes"
            INFO=:
            ;;
        *)
            echo "usage: $0 [-n|--yes|--cron] nnn[MG]"
            fail "Unknown option '$1'"
            ;;
    esac
done

# Argument parsing
case "$1" in
    [0-9]*m|[0-9]*g|[0-9]*M|[0-9]*G|[0-9]*)
        block=1
        requested=$(tr -dc [0-9] <<<"$1")
        unit=$(tr -d [0-9] <<<"$1" | tr [a-z] [A-Z])
        test "$unit" != 'G' || block=$GiB
        test "$unit" != 'M' || block=$(( 1024 * 1024 ))
        requested=$(( $requested * $block))
        shift
        ;;
    '')
        requested=$(( 8 * $GiB ))
        ;;
    *)
        fail "Expecting a numeric argument: '$1'"
        ;;
esac

test $requested -le $(( $MAX_REQUEST_GiB * $GiB )) \
    || fail "You cannot request more than $MAX_REQUEST_GiB GiB, you wanted $(print_gib $requested)!"


#
# Helpers
#
log() {
    echo $(date +"%Y-%m-%d %H:%M:%S") "$@"
}

check_guard_file() {
    pid=$$
    script=$(basename $0)
    guard="/tmp/$script-$(id -nu).pid"
    if test -f $guard ; then
        $INFO "Script already runs... own PID=$pid; others: $(ps auxw | grep $script | grep -v grep)"
        exit 69
    fi
    trap "rm -f $guard" EXIT ERR TERM
    echo $pid >$guard
    ##sleep 30; exit
}

download_free() {
    bytes_free "/var/torrent/" # TODO: make this configurable
}

items_loaded() {
    ~/bin/rtxmlrpc view.size '' main
}

finished() {
    after_items=$(items_loaded)
    after_free=$(download_free)
    took_secs=$(took_ms $start_tm)

    if test $start_items -ne $after_items; then
        $INFO "Removed $(( $start_items - $after_items )) item(s)," \
            "freeing $(print_gib $(( $after_free - $start_free ))) disk space" \
            "[now $(print_gib $(download_free)) free, took ${took_secs}s]."
    fi

    $INFO "Disk space management finished in ${took_secs}s [$(print_gib $(download_free)) free," \
        "$(print_gib $requested) requested]"

    exit 0
}

make_space() {
    test $(download_free) -lt $needed || finished
    rc=0
    test "$1" = "--aggressive" && { shift; activity=5i; } || activity=4h
    while test $(download_free) -lt $needed -a $rc -ne 44; do
        set +e
        $DRY ~/bin/rtcontrol -/1 --cull active=+$activity [ NOT [ $PROTECTED ] ] \
            -qco loaded,size.sz,uploaded.sz,seedtime,ratio,name "$@" $INTERACTIVE; rc=$?
        set -e
        if $simulate; then break; fi
        ##echo "RC=$rc for" "$@"
        test $rc -eq 0 -o $rc -eq 44 || fail "rtcontrol aborted with RC=$rc"
    done
    test $(download_free) -lt $needed || finished
    $INFO "No matches for" "$@"
}


# Calculate target
needed=$(( $requested + $RESERVED_GiB * $GiB )) # Add a few GiB for the system

# Remember start state
start_items=$(items_loaded)
start_free=$(download_free)

# ANY disk check must run protected by the lock, else there's race conditions!
check_guard_file

# Exit immediately if there's enough space
test $(download_free) -lt $needed || exit 0

start_tm=$(now)
$INFO "Disk space management started [with $(print_gib $(download_free)) free]"

# Execute rules
source ~/etc/sweep_rules

# Finally, go through everything sorted by age
make_space -s loaded // -/5
make_space --aggressive -s loaded // -/5

# As it says…
finished