#!/bin/bash
#%# family=auto

: << EOF
=head1 NAME
docker_volumesize - Plugin to monitor the sizes of docker volumes.

=head1 AUTHOR

Michael Grote (michael.grote@posteo.de)

=head1 MAGIC MARKERS

#%# family=auto

=head1 LICENSE

GPLv3 or later

SPDX-License-Identifier: GPL-3.0-or-later

=cut

EOF


if [ "$1" = "autoconf" ]; then
  if ! command -v jq &> /dev/null; then
    echo "no (jq could not be found)"
  elif ! command -v docker &> /dev/null; then
    echo "no (docker could not be found)"
  elif ! command -v bc &> /dev/null; then
    echo "no (bc could not be found)"
  else
    echo "yes"
  fi
  exit 0
fi

volume_info=$(docker system df -v --format '{{json .Volumes}}' | jq -r '.[] | "\(.Name):\(.Size):\(.Labels)"')



if [ "$1" = "config" ]; then
  echo "multigraph volumesize"
  echo "graph_title Docker volume size"
  echo "graph_vlabel Bytes"
  echo "graph_category virtualization"
  echo "graph_args -l 0 --base 1024"
  echo "graph_info This graph shows the size per volume."
  while IFS= read -r line; do
    echo "$line" | awk 'BEGIN { FS = ":" } { label = substr($1, 1, 30); print $1 ".label " label }'
    # display info only when labels are set
    if [ -n "$(echo "$line" | awk 'BEGIN { FS = ":" } { print $3 }')" ]; then
      echo "$line" | awk 'BEGIN { FS = ":" } { print $1".info "$3 }'
    fi
    echo "$line" | awk 'BEGIN { FS = ":" } { print $1".draw AREASTACK" }'
  done <<< "$volume_info"
exit 0
fi

echo "multigraph volumesize"
while IFS= read -r line; do
  name=$(echo "$line" | awk 'BEGIN { FS = ":" } { print $1 }')
  value=$(echo "$line" | awk 'BEGIN { FS = ":" } { print $2 }')

  if [[ $value =~ ([0-9.]+)TB$ ]]; then
    bytes=$(echo "$(echo $value | sed 's/[^0-9.]//g') * 1024 * 1024 * 1024 * 1024" | bc)
  elif [[ $value =~ ([0-9.]+)GB$ ]]; then
    bytes=$(echo "$(echo $value | sed 's/[^0-9.]//g') * 1024 * 1024 * 1024" | bc)
  elif [[ $value =~ ([0-9.]+)MB$ ]]; then
    bytes=$(echo "$(echo $value | sed 's/[^0-9.]//g') * 1024 * 1024" | bc)
  elif [[ $value =~ ([0-9.]+)kB$ ]]; then
    bytes=$(echo "$(echo $value | sed 's/[^0-9.]//g') * 1024" | bc)
  elif [[ $value =~ ([0-9.]+)B$ ]]; then
    bytes=$(echo "$(echo $value | sed 's/[^0-9.]//g')")
  fi
  echo "$name.value" "$bytes"
done <<< "$volume_info"