WTF!, when did those files get deleted ?!

Tuesday, October 25, 2011

A guy I work with recently showed me a bad situation he had with iPhoto, some family videos had gone missing from his harddisk. The thumbnails were in iPhoto, but when he clicked on them, they wouldn't play because the files were gone. He had Time Machine backups, but they were gone even in the oldest copies. Apparently the files had been deleted quite a while ago.

This got me thinking about a huge problem with backups - you can be very diligent about keeping them, but if you have no idea that something's missing they don't do you much good.

What you need is something that would alert you of unexpected deletions. Thinking about my friend's experience, I whipped together a small shell script that would be run periodically to take an inventory of the iPhoto originals, and if something was removed compared to the last run, it would place a file on my desktop that hopefully I'd notice, listing a diff of the changes.

I saved this on my disk as /Users/barryp/bin/inventory_iphoto.sh

#!/bin/bash
#
# Check if anything has been deleted from the iPhoto Originals
# folder, and if so, place a file on the Desktop listing what's
# gone missing
#

CHECK_FILE=~/Library/Logs/com.diskcompare.inventory_iphoto.txt

find ~/Pictures/iPhoto\ Library/Originals -type f | sort >$CHECK_FILE.new
if [ -e $CHECK_FILE ]
then
    diff -u $CHECK_FILE $CHECK_FILE.new >$CHECK_FILE.diff
    grep '^-/' $CHECK_FILE.diff >$CHECK_FILE.gone
    if [ -s $CHECK_FILE.gone ]
    then
        mv $CHECK_FILE.diff "$HOME/Desktop/DELETED iPhoto files-`date "+%Y-%m-%d %H%M%S"`.txt"
    else
        rm $CHECK_FILE.diff
    fi
    rm $CHECK_FILE.gone
fi
mv $CHECK_FILE.new $CHECK_FILE

and made it executable with

chmod +x /Users/barryp/bin/inventory_iphoto.sh

Other than the directory name to check, there's nothing iPhoto or even Mac specific about this, it could be easily adapted for other uses.

You can run the script manually too anytime you want, and you can test this out by running once, editing ~/Library/Logs/com.diskcompare.inventory_iphoto.txt to add a line (starting with a /), and then running the script again to make sure a diff file pops up on your desktop showing how the line you manually added is gone in the updated inventory.

Next, I setup the Mac to run this once a day or so, by creating a launchd job saved as /Users/barryp/Library/LaunchAgents/com.diskcompare.inventory_iphoto.plist

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
    <key>Label</key>
    <string>com.diskcompare.inventory_iphoto</string>
    <key>ProgramArguments</key>
    <array>
        <string>/Users/barryp/bin/inventory_photo.sh</string>
    </array>
    <key>StartInterval</key>
    <integer>86400</integer>
</dict>
</plist>

(You'll have to change the path to the script to suit your setup, unfortunately it doesn't seem you can use tilde expansion in a launchd job)

and then activated it in launchd with this command at the command prompt:

launchctl load ~/Library/LaunchAgents/com.diskcompare.inventory_iphoto.plist

Fortunately my friend found a really old harddisk that happened to have his missing videos on it, but he's even more lucky to have noticed the problem in the first place.

With a periodic inventory as described above, hopefully a person would become aware of a problem with in a day or two, in plenty of time get the files out of a backup system.

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