#!/bin/sh
#
# /usr/local/bin/wp-content-cache.sh
#
# Copyright 2012 - Jean-Sebastien Morisset - http://surniaulula.com/
#
# This script is free software; you can redistribute it and/or modify it under
# the terms of the GNU General Public License as published by the Free Software
# Foundation; either version 3 of the License, or (at your option) any later
# version.
#
# This script is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
# FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
# details at http://www.gnu.org/licenses/.

base_dir="/export/www/*"
wp_content="/wordpress/wp-content"

# read command line opts
while :
do
	for arg in "$@"
	do
		case $arg in
			-h|--help)
				echo -e "\npurpose: display size and number of files in WP cache folders prime and optionally flush the OS disk cache.\n"
				echo -e " syntax: $0 [-h|--help] [-f|--flush] {sitedirs}\n"
				printf "%15s: %s\n" "--flush" "sync and drop the OS disk cache before priming."
				printf "%15s: %s\n\n" "{sitedirs}" "optional path to website(s) base folder (default is $base_dir)."
				exit 0
				;;
			-f|--flush)
				flush="1"
				shift 1
				;;
			-*)	echo "error: unrecognized command line argument."
				exit 1
				;;
                        *)	args[$(( i++ ))]="$1"
				shift 1
				;;
		esac
		continue 2
	done
	break
done

# reset $1, $2, etc. with left-over parameters
set -- "${args[@]}"

# set default sitedir(s) if none specified
[ -z "$@" ] && set -- $base_dir

if [ -n "$flush" ]
then
	echo "(sync'ing disks)"
	sync
	echo "(droping caches)"
	if [ -w /proc/sys/vm/drop_caches ]
	then
		#
		# (excerpt from http://www.bramschoenmakers.nl/node/310)
		#
		# Erase the page cache. This part of the disk cache contains actual file contents.
		#
		# echo 1 >/proc/sys/vm/drop_caches
		#
		# Erase the inode and dentry caches (short: dcache). An inode is the data
		# structure used by the kernel to represent a file. It does not contain the
		# file's data, only attributes like the name, dates and permissions. A dentry
		# is a data structure to represent a file path, which maps to an actual file.
		#
		# echo 2 >/proc/sys/vm/drop_caches
		#
		# Erase both the page cache, as the inode cache and dcache.
		#
		echo 3 >/proc/sys/vm/drop_caches
	else
		echo "error: cannot write to /proc/sys/vm/drop_caches file!"
	fi
fi

time {
	for website in "$@"
	do
		if [ -d "$website$wp_content" ]
		then
			echo "`basename $website`:"
			# find any directory named "cache" anywhere under wp-content, or "*-cache" directly 
			# under wp-content (for "widget-cache" and others).
			find "$website$wp_content/" \( -name "cache" -o -regex "^$website$wp_content/[^/]*-cache" \) \
				-type d -print | while read cache_dir
			do
				printf "\t%-65s %6s %6s files\n" "`echo \"$cache_dir\"|sed \"s!$website/!!\"`" \
					"`du -sh "$cache_dir/"|cut -f 1`" "`find "$cache_dir/" -type f -print|wc -l`"
				find "$cache_dir/" -type f -exec cat {} \; >/dev/null
			done
		fi
	done
}