Get layers from DXF files using ogrinfo

sh-ogrgetlayers.sh

#!/bin/bash

# sh-ogrgetlayers.sh
# -i input DXF file
# Output all dxf files and their layers to layers.csv. Layers in array format ['a','b']
# 
# To execute in batch mode:
# find . -iname "*.dxf" -print0 | xargs -0 -I {} ./sh-ogrgetlayers.sh -i "{}"
#
# Requires ogrinfo, uses sed and grep, tested on OS X 10.13.3
# By Joakim Skjefstad

while getopts ":i:" opt; do
  case $opt in
    i)
      echo "-i was triggered, Parameter: $OPTARG" >&2
      FILENAME=${OPTARG##*/}
      PATHNAME=`dirname "$OPTARG"`
      FILE=${FILENAME%.*}
      echo "Working on $PATHNAME/$FILENAME"
      LAYERS=$(ogrinfo "$OPTARG" -dialect SQLITE -sql "SELECT group_concat(DISTINCT layer) AS layers FROM entities ORDER BY layer ASC" | grep 'layers (String)' | sed 's/.*= //' | sed s/,/\',\'/g | sed s/^/[\'/ | sed s/$/\']/)
      echo "$FILENAME,$LAYERS" >> layers.csv
      ;;
    \?)
      echo "Invalid option: -$OPTARG" >&2
      exit 1
      ;;
    :)
      echo "Option -$OPTARG requires an argument." >&2
      exit 1
      ;;
  esac
done