handlers/maildir

   1 ###############################################################
   2 #
   3 #  This handler slowly creates a backup of each user's maildir
   4 #  to a remote server. It is designed to be run with low overhead
   5 #  in terms of cpu and bandwidth so it runs pretty slow.
   6 #
   7 #  if destdir is /backup/maildir/, then it will contain the files
   8 #    daily.1
   9 #    daily.2
  10 #    daily.3
  11 #    weekly.1
  12 #    weekly.2
  13 #    monthly.1
  14 #  if keepdaily is 3, keepweekly is 2, and keepmonthly is 1.
  15 #
  16 ##############################################################
  17
  18 getconf rotate yes
  19 getconf remove yes
  20
  21 getconf loadlimit 5
  22 getconf speedlimit 0
  23 getconf keepdaily 5
  24 getconf keepweekly 3
  25 getconf keepmonthly 1
  26
  27 getconf srcdir /var/maildir
  28 getconf destdir
  29 getconf desthost
  30 getconf destport 22
  31 getconf destuser
  32
  33 failedcount=0
  34
  35 # strip trailing /
  36 destdir=${destdir%/}
  37 srcdir=${srcdir%/}
  38
  39 # used for testing
  40 #getconf letter
  41 #getconf testuser elijah
  42 getconf backup yes
  43 #letters=e
  44 letters="a b c d e f g h i j k l m n o p q r s t u v w x y z"
  45
  46 [ -d $srcdir ] || fatal "source directory $srcdir doesn't exist"
  47
  48 [ ! $test ] || testflags="--dry-run -v"
  49 rsyncflags="$testflags -e 'ssh -p $destport' -r -v --ignore-existing --delete --size-only --bwlimit=$speedlimit"
  50 excludes="--exclude '.Trash/\*' --exclude '.Mistakes/\*' --exclude '.Spam/\*'"
  51
  52 # see if we can login
  53 debug "ssh -o PasswordAuthentication=no $desthost -l $destuser 'echo -n 1'"
  54 if [ ! $test ]; then
  55         result=`ssh -o PasswordAuthentication=no $desthost -l $destuser 'echo -n 1' 2>&1`
  56         if [ "$result" != "1" ]; then
  57                 fatal "Can't connect to $desthost as $destuser."
  58         fi
  59 fi
  60
  61 ##################################################################
  62 ### FUNCTIONS
  63
  64 function do_user() {
  65         local user=$1
  66         local destdir=$2
  67         local letter=${user:0:1}
  68         local dir="$srcdir/$letter/$user"
  69         [ -d $dir ] || fatal "maildir $dir not found".
  70
  71 #       while true; do
  72 #               load=`uptime | sed 's/^.*load average: \\([^,]*\\).*$/\\1/'`
  73 #               over=`expr $load \> $loadlimit`
  74 #               if [ $over == 1 ]; then
  75 #                       info "load $load, sleeping..."
  76 #                       sleep 600
  77 #               else
  78 #                       break
  79 #               fi
  80 #       done
  81
  82         cmd="$RSYNC $rsyncflags $excludes $dir $destuser@$desthost:$destdir/$letter"
  83         ret=`rsync -e "ssh -p $destport" -r \
  84 --links --ignore-existing --delete --size-only --bwlimit=$speedlimit \
  85 --exclude '.Trash/*' --exclude '.Mistakes/*' --exclude '.Spam/*' \
  86 $dir $destuser@$desthost:$destdir/$letter \
  87 2>&1`
  88         if [ $? != 0 ]; then
  89                 warning "rsync $user failed"
  90                 warning "  returned: $ret"
  91                 let "failedcount = failedcount + 1"
  92                 if [ $failedcount -gt 100 ]; then
  93                         fatal "100 rsync errors -- something is not working right. bailing out."
  94                 fi
  95         fi
  96 }
  97
  98 # remove any maildirs from backup which might have been deleted
  99 # and add new ones which have just been created.
 100
 101 function do_remove() {
 102         local tmp1=/tmp/maildirtmpfile$$
 103         local tmp2=/tmp/maildirtmpfile$$
 104
 105         for i in a b c d e f g h i j k l m n o p q r s t u v w x y z; do
 106                 ls -1 "$srcdir/$i" | sort > $tmp1
 107                 ssh -p $destport $desthost ls -1 '$destdir/maildir/$i' | sort > $tmp2
 108                 for deluser in `join -v 2 $tmp1 $tmp2`; do
 109                         cmd="ssh -p $destport $desthost rm -vr '$destdir/maildir/$i/$deluser/'"
 110                         debug $cmd
 111                 done
 112         done
 113         rm $tmp1
 114         rm $tmp2
 115 }
 116
 117 function do_rotate() {
 118         backuproot=$destdir
 119
 120 (
 121         debug Connecting to $desthost
 122         ssh -T -o PasswordAuthentication=no $desthost -l $destuser <<EOF
 123 ##### BEGIN REMOTE SCRIPT #####
 124         seconds_daily=86400
 125         seconds_weekly=604800
 126         seconds_monthly=2628000
 127         keepdaily=$keepdaily
 128         keepweekly=$keepweekly
 129         keepmonthly=$keepmonthly
 130         now=\`date +%s\`
 131
 132         for rottype in daily weekly monthly; do
 133                 seconds=\$((seconds_\${rottype}))
 134
 135                 dir="$backuproot/\$rottype"
 136                 if [ ! -d \$dir.1 ]; then
 137                         echo "Info: \$dir.1 does not exist. This backup is missing, so we are skipping the rotation."
 138                         continue 1
 139                 elif [ ! -f \$dir.1/created ]; then
 140                         echo "Warning: \$dir.1/created does not exist. This backup may be only partially completed. Skipping rotation."
 141                         continue 1
 142                 fi
 143
 144                 # Rotate the current list of backups, if we can.
 145                 oldest=\`find $backuproot -type d -maxdepth 1 -name \$rottype'.*' | sed 's/^.*\.//' | sort -n | tail -1\`
 146                 echo "Debug: oldest \$oldest"
 147                 [ "\$oldest" == "" ] && oldest=0
 148                 for (( i=\$oldest; i > 0; i-- )); do
 149                         if [ -d \$dir.\$i ]; then
 150                                 if [ -f \$dir.\$i/rotated ]; then
 151                                         rotated=\`tail -1 \$dir.\$i/rotated\`
 152                                 else
 153                                         rotated=0
 154                                 fi
 155                                 cutoff_time=\$(( now - (seconds*i) ))
 156                                 if [ \$rotated -lt \$cutoff_time ]; then
 157                                         next=\$(( i + 1 ))
 158                                         if [ ! -d \$dir.\$next ]; then
 159                                                 echo "mv \$dir.\$i \$dir.\$next"
 160                                                 mv \$dir.\$i \$dir.\$next
 161                                                 date +%c%n%s > \$dir.\$next/rotated
 162                                         else
 163                                                 echo "Info: skipping rotation of \$dir.\$i because \$dir.\$next already exists."
 164                                         fi
 165                                 else
 166                                         echo "Info: skipping rotation of \$dir.\$i because it was rotated" \$(( (now-rotated)/86400)) "days ago ("\$(( (now-cutoff_time)/86400))" needed)."
 167                                 fi
 168                         fi
 169                 done
 170         done
 171
 172         max=\$((keepdaily+1))
 173         if [ \( \$keepweekly -gt 0 -a -d $backuproot/daily.\$max \) -a ! -d $backuproot/weekly.1 ]; then
 174                 echo mv $backuproot/daily.\$max $backuproot/weekly.1
 175                 mv $backuproot/daily.\$max $backuproot/weekly.1
 176                 date +%c%n%s > $backuproot/weekly.1/rotated
 177         fi
 178
 179         max=\$((keepweekly+1))
 180         if [ \( \$keepmonthly -gt 0 -a -d $backuproot/weekly.\$max \) -a ! -d $backuproot/monthly.1 ]; then
 181                 echo mv $backuproot/weekly.\$max $backuproot/monthly.1
 182                 mv $backuproot/weekly.\$max $backuproot/monthly.1
 183                 date +%c%n%s > $backuproot/monthly.1/rotated
 184         fi
 185
 186         for rottype in daily weekly monthly; do
 187                 max=\$((keep\${rottype}+1))
 188                 dir="$backuproot/\$rottype"
 189                 oldest=\`find $backuproot -type d -maxdepth 1 -name \$rottype'.*' | sed 's/^.*\.//' | sort -n | tail -1\`
 190                 [ "\$oldest" == "" ] && oldest=0
 191                 # if we've rotated the last backup off the stack, remove it.
 192                 for (( i=\$oldest; i >= \$max; i-- )); do
 193                         if [ -d \$dir.\$i ]; then
 194                                 if [ -d $backuproot/rotate.tmp ]; then
 195                                         echo "Info: removing $backuproot/rotate.tmp"
 196                                         rm -rf $backuproot/rotate.tmp
 197                                 else
 198                                         echo "Info: moving \$dir.\$i to $backuproot/rotate.tmp"
 199                                         mv \$dir.\$i $backuproot/rotate.tmp
 200                                 fi
 201                         fi
 202                 done
 203         done
 204 ####### END REMOTE SCRIPT #######
 205 EOF
 206 ) | (while read a; do passthru $a; done)
 207
 208 }
 209
 210
 211 function setup_remote_dirs() {
 212         local backuptype=$1
 213         local dir="$destdir/$backuptype"
 214
 215 (
 216         ssh -T -o PasswordAuthentication=no $desthost -l $destuser <<EOF
 217                 if [ ! -d $destdir ]; then
 218                         echo "Fatal: Destination directory $destdir does not exist on host $desthost."
 219                         exit 1
 220                 elif [ -d $dir.1 ]; then
 221                         if [ -f $dir.1/created ]; then
 222                                 echo "Warning: $dir.1 already exists. Overwriting contents."
 223                         else
 224                                 echo "Warning: we seem to be resuming a partially written $dir.1"
 225                         fi
 226                 else
 227                         if [ -d $destdir/rotate.tmp ]; then
 228                                 mv $destdir/rotate.tmp $dir.1
 229                                 if [ \$? == 1 ]; then
 230                                         echo "Fatal: could mv $destdir/rotate.tmp $dir.1 on host $desthost"
 231                                         exit 1
 232                                 fi
 233                         else
 234                                 mkdir $dir.1
 235                                 if [ \$? == 1 ]; then
 236                                         echo "Fatal: could not create directory $dir.1 on host $desthost"
 237                                         exit 1
 238                                 fi
 239                         fi
 240                         if [ -d $destdir/$backuptype.2 ]; then
 241                                 echo "Info: updating hard links to $dir.1. This may take a while."
 242                                 cp -al $destdir/$backuptype.2/. $dir.1
 243                                 if [ \$? == 1 ]; then
 244                                         echo "Fatal: could not create hard links to $dir.1 on host $desthost"
 245                                         exit 1
 246                                 fi
 247                         fi
 248                 fi
 249                 [ -f $dir.1/created ] && rm $dir.1/created
 250                 [ -f $dir.1/rotated ] && rm $dir.1/rotated
 251                 exit 0
 252 EOF
 253 ) | (while read a; do passthru $a; done)
 254
 255         if [ $? == 1 ]; then exit; fi
 256 }
 257
 258 ###
 259 ##################################################################
 260
 261 ### ROTATE BACKUPS ###
 262
 263 if [ "$rotate" == "yes" ]; then
 264         do_rotate
 265 fi
 266
 267 ### REMOVE OLD MAILDIRS ###
 268
 269 if [ "$remove" == "yes" ]; then
 270         debug remove
 271 fi
 272
 273 ### MAKE BACKUPS ###
 274
 275 if [ "$backup" == "yes" ]; then
 276         if [ $keepdaily -gt 0 ]; then btype=daily
 277         elif [ $keepweekly -gt 0 ]; then btype=weekly
 278         elif [ $keepmonthly -gt 0 ]; then btype=monthly
 279         else fatal "keeping no backups"; fi
 280
 281         setup_remote_dirs $btype
 282
 283         for i in $letters; do
 284                 [ -d "$srcdir/$i" ] || fatal "directory $srcdir/$i not found."
 285                 cd "$srcdir/$i"
 286                 debug $i
 287                 for user in `ls -1`; do
 288                         if [ "$testuser" != "" -a "$testuser" != "$user" ]; then continue; fi
 289                         do_user $user $destdir/$btype.1
 290                 done
 291         done
 292
 293         ssh -o PasswordAuthentication=no $desthost -l $destuser "date +%c%n%s > $destdir/$btype.1/created"
 294 fi