George MacKerron: code blog

#!/bin/bash
 
# --- Set backup parameters ---
 
# What local files/folders are we backing up?
SRC="/Users/gjm06/Development /Users/gjm06/Documents /Users/gjm06/Sites"
 
# What server are we backing up to?
DESTSERVER="george.example.com"
 
# What's our user name on the server?
SSHUSER="george"
 
# What's the remote shell command for this server 
# (slight obscurity/security by avoiding port 22)
RSH="ssh -p 2244"
 
# What location on the server shall we back up to?
DESTPATH="/home/george/backups"
 
# Any non-valuable stuff to exclude by name/location?
EXCLUDE=".DS_Store,.svn/,.Trash/,tmp/,log/,vendor/"
 
# Exclude things that are *how* big? 
# e.g. I don't want GBs of virtual machines going over the wire
# (NB. this is in bytes)
MAXFILESIZE=100000
 
 
# --- Set Growl parameters ---
 
# What will this script be called in the Growl prefpane?
GROWLNAME="Remote backup script"
 
# And what app's icon will appear in Growl notifications?
APPICON="Time Machine"
 
 
# --- Do it! ---
 
echo Checking not already running 
 
PROCS=`ps -A -o "pid=,command="`
MYNAME="$0"
MYBASENAME=`basename $MYNAME`
MYPID=$$
 
# The next line works like so:
# * take the process list (for all users),
# * filter *in* processes named like this script (making sure we're on word boundaries),
# * filter *out* (-v) the one that *is* this script (by PID), and finally
# * filter *out* the grep commands themselves.
 
MERUNNING=`echo "$PROCS" | grep -E -e "\b$MYBASENAME\b" \
  | grep -E -v "\b$MYPID\b" | grep -v grep`
 
# Then, if anything's left (i.e. MERUNNING isn't a zero-length string...)
 
if [ ! -z "$MERUNNING" ]; then
  /usr/local/bin/growlnotify --name "$GROWLNAME" --appIcon "$APPICON" \
    --message "Another backup seems to be in progress" \
    "Ignoring scheduled backup"
  exit 1
fi
 
 
echo Finding large files to exclude...
 
OVERSIZELIST="/tmp/files_over_backup_limit"
find $SRC -size +$MAXFILESIZE > $OVERSIZELIST
 
# If you ever want to know what's excluded -- and you should! -- just do
# a 'cat /tmp/files_over_backup_limit' in the Terminal
 
# Next, 'wc -l' counts the *lines* in our oversize list, and we extract 
# just the number from the output
 
NUMOVERSIZE=`wc -l "$OVERSIZELIST" | grep -o -E [0123456789]+`
 
 
echo Rsyncing...
 
# date makes up the name for our archive folders, while
# eval is used to invoke shell expansion on the list of file names to exclude,
# turning them into a list of --exclude= statements
 
BDATE=`date "+%y_%m_%d-%H.%M.%S"`
EXPEXCLUDES=`eval "echo --exclude={$EXCLUDE} "`
ERRORS="/tmp/rsync_backup_errors"
 
# The && and || operators give us a simple way to respond to zero and 
# non-zero (= error) rsync exit codes, thanks to lazy evaluation by the shell
 
rsync --rsh="$RSH" \
  --recursive --partial --delete --delete-excluded \
  --links --times --relative --compress \
  --backup --backup-dir="$DESTPATH/Archive/$BDATE/" \
  --exclude-from="$OVERSIZELIST" \
  $EXPEXCLUDES \
  $SRC \
  $SSHUSER@$DESTSERVER:"$DESTPATH/Current/" \
  2>"$ERRORS" \
&& 
/usr/local/bin/growlnotify --name "$GROWLNAME" --appIcon "$APPICON" \
  --message "Backed up to $DESTSERVER, $NUMOVERSIZE oversized files excluded" \
  "Completed backup" \
|| \
/usr/local/bin/growlnotify --name "$GROWLNAME" --appIcon "$APPICON" -s \
  --message "`cat "$ERRORS"`" \
  "Failed backup"