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         ret=$?
  89         # ignore 0 (success) and 24 (file vanished before it could be copied)
  90         if [ $ret != 0 -a $ret != 24 ]; then
  91                 warning "rsync $user failed"
  92                 warning "  returned: $ret"
  93                 let "failedcount = failedcount + 1"
  94                 if [ $failedcount -gt 100 ]; then
  95                         fatal "100 rsync errors -- something is not working right. bailing out."
  96                 fi
  97         fi
  98 }
  99
 100 # remove any maildirs from backup which might have been deleted
 101 # and add new ones which have just been created.
 102
 103 function do_remove() {
 104         local tmp1=/tmp/maildirtmpfile$$
 105         local tmp2=/tmp/maildirtmpfile$$
 106
 107         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
 108                 ls -1 "$srcdir/$i" | sort > $tmp1
 109                 ssh -p $destport $desthost ls -1 '$destdir/maildir/$i' | sort > $tmp2
 110                 for deluser in `join -v 2 $tmp1 $tmp2`; do
 111                         cmd="ssh -p $destport $desthost rm -vr '$destdir/maildir/$i/$deluser/'"
 112                         debug $cmd
 113                 done
 114         done
 115         rm $tmp1
 116         rm $tmp2
 117 }
 118
 119 function do_rotate() {
 120         backuproot=$destdir
 121
 122 (
 123         debug Connecting to $desthost
 124         ssh -T -o PasswordAuthentication=no $desthost -l $destuser <<EOF
 125 ##### BEGIN REMOTE SCRIPT #####
 126         seconds_daily=86400
 127         seconds_weekly=604800
 128         seconds_monthly=2628000
 129         keepdaily=$keepdaily
 130         keepweekly=$keepweekly
 131         keepmonthly=$keepmonthly
 132         now=\`date +%s\`
 133
 134         for rottype in daily weekly monthly; do
 135                 seconds=\$((seconds_\${rottype}))
 136
 137                 dir="$backuproot/\$rottype"
 138                 if [ ! -d \$dir.1 ]; then
 139                         echo "Info: \$dir.1 does not exist. This backup is missing, so we are skipping the rotation."
 140                         continue 1
 141                 elif [ ! -f \$dir.1/created ]; then
 142                         echo "Warning: \$dir.1/created does not exist. This backup may be only partially completed. Skipping rotation."
 143                         continue 1
 144                 fi
 145
 146                 # Rotate the current list of backups, if we can.
 147                 oldest=\`find $backuproot -type d -maxdepth 1 -name \$rottype'.*' | sed 's/^.*\.//' | sort -n | tail -1\`
 148                 echo "Debug: oldest \$oldest"
 149                 [ "\$oldest" == "" ] && oldest=0
 150                 for (( i=\$oldest; i > 0; i-- )); do
 151                         if [ -d \$dir.\$i ]; then
 152                                 if [ -f \$dir.\$i/created ]; then
 153                                         created=\`tail -1 \$dir.\$i/created\`
 154                                 else
 155                                         created=0
 156                                 fi
 157                                 cutoff_time=\$(( now - (seconds*(i-1)) ))
 158                                 if [ ! \$created -gt \$cutoff_time ]; then
 159                                         next=\$(( i + 1 ))
 160                                         if [ ! -d \$dir.\$next ]; then
 161                                                 echo "Debug: mv \$dir.\$i \$dir.\$next"
 162                                                 mv \$dir.\$i \$dir.\$next
 163                                                 date +%c%n%s > \$dir.\$next/rotated
 164                                         else
 165                                                 echo "Info: skipping rotation of \$dir.\$i because \$dir.\$next already exists."
 166                                         fi
 167                                 else
 168                                         echo "Info: skipping rotation of \$dir.\$i because it was created" \$(( (now-created)/86400)) "days ago ("\$(( (now-cutoff_time)/86400))" needed)."
 169                                 fi
 170                         fi
 171                 done
 172         done
 173
 174         max=\$((keepdaily+1))
 175         if [ \( \$keepweekly -gt 0 -a -d $backuproot/daily.\$max \) -a ! -d $backuproot/weekly.1 ]; then
 176                 echo mv $backuproot/daily.\$max $backuproot/weekly.1
 177                 mv $backuproot/daily.\$max $backuproot/weekly.1
 178                 date +%c%n%s > $backuproot/weekly.1/rotated
 179         fi
 180
 181         max=\$((keepweekly+1))
 182         if [ \( \$keepmonthly -gt 0 -a -d $backuproot/weekly.\$max \) -a ! -d $backuproot/monthly.1 ]; then
 183                 echo mv $backuproot/weekly.\$max $backuproot/monthly.1
 184                 mv $backuproot/weekly.\$max $backuproot/monthly.1
 185                 date +%c%n%s > $backuproot/monthly.1/rotated
 186         fi
 187
 188         for rottype in daily weekly monthly; do
 189                 max=\$((keep\${rottype}+1))
 190                 dir="$backuproot/\$rottype"
 191                 oldest=\`find $backuproot -type d -maxdepth 1 -name \$rottype'.*' | sed 's/^.*\.//' | sort -n | tail -1\`
 192                 [ "\$oldest" == "" ] && oldest=0
 193                 # if we've rotated the last backup off the stack, remove it.
 194                 for (( i=\$oldest; i >= \$max; i-- )); do
 195                         if [ -d \$dir.\$i ]; then
 196                                 if [ -d $backuproot/rotate.tmp ]; then
 197                                         echo "Info: removing $backuproot/rotate.tmp"
 198                                         rm -rf $backuproot/rotate.tmp
 199                                 fi
 200                                 echo "Info: moving \$dir.\$i to $backuproot/rotate.tmp"
 201                                 mv \$dir.\$i $backuproot/rotate.tmp
 202                         fi
 203                 done
 204         done
 205 ####### END REMOTE SCRIPT #######
 206 EOF
 207 ) | (while read a; do passthru $a; done)
 208
 209 }
 210
 211
 212 function setup_remote_dirs() {
 213         local backuptype=$1
 214         local dir="$destdir/$backuptype"
 215
 216 (
 217         ssh -T -o PasswordAuthentication=no $desthost -l $destuser <<EOF
 218                 if [ ! -d $destdir ]; then
 219                         echo "Fatal: Destination directory $destdir does not exist on host $desthost."
 220                         exit 1
 221                 elif [ -d $dir.1 ]; then
 222                         if [ -f $dir.1/created ]; then
 223                                 echo "Warning: $dir.1 already exists. Overwriting contents."
 224                         else
 225                                 echo "Warning: we seem to be resuming a partially written $dir.1"
 226                         fi
 227                 else
 228                         if [ -d $destdir/rotate.tmp ]; then
 229                                 mv $destdir/rotate.tmp $dir.1
 230                                 if [ \$? == 1 ]; then
 231                                         echo "Fatal: could mv $destdir/rotate.tmp $dir.1 on host $desthost"
 232                                         exit 1
 233                                 fi
 234                         else
 235                                 mkdir $dir.1
 236                                 if [ \$? == 1 ]; then
 237                                         echo "Fatal: could not create directory $dir.1 on host $desthost"
 238                                         exit 1
 239                                 fi
 240                                 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 y x z; do
 241                                         mkdir $dir.1/\$i
 242                                 done
 243                         fi
 244                         if [ -d $destdir/$backuptype.2 ]; then
 245                                 echo "Info: updating hard links to $dir.1. This may take a while."
 246                                 cp -alf $destdir/$backuptype.2/. $dir.1
 247                                 #if [ \$? == 1 ]; then
 248                                 #       echo "Fatal: could not create hard links to $dir.1 on host $desthost"
 249                                 #       exit 1
 250                                 #fi
 251                         fi
 252                 fi
 253                 [ -f $dir.1/created ] && rm $dir.1/created
 254                 [ -f $dir.1/rotated ] && rm $dir.1/rotated
 255                 exit 0
 256 EOF
 257 ) | (while read a; do passthru $a; done)
 258
 259         if [ $? == 1 ]; then exit; fi
 260 }
 261
 262 ###
 263 ##################################################################
 264
 265 ### ROTATE BACKUPS ###
 266
 267 if [ "$rotate" == "yes" ]; then
 268         do_rotate
 269 fi
 270
 271 ### REMOVE OLD MAILDIRS ###
 272
 273 if [ "$remove" == "yes" ]; then
 274         debug remove
 275 fi
 276
 277 ### MAKE BACKUPS ###
 278
 279 if [ "$backup" == "yes" ]; then
 280         if [ $keepdaily -gt 0 ]; then btype=daily
 281         elif [ $keepweekly -gt 0 ]; then btype=weekly
 282         elif [ $keepmonthly -gt 0 ]; then btype=monthly
 283         else fatal "keeping no backups"; fi
 284
 285         setup_remote_dirs $btype
 286
 287         for i in $letters; do
 288                 [ -d "$srcdir/$i" ] || fatal "directory $srcdir/$i not found."
 289                 cd "$srcdir/$i"
 290                 debug $i
 291                 for user in `ls -1`; do
 292                         if [ "$testuser" != "" -a "$testuser" != "$user" ]; then continue; fi
 293                         do_user $user $destdir/$btype.1
 294                 done
 295         done
 296
 297         ssh -o PasswordAuthentication=no $desthost -l $destuser "date +%c%n%s > $destdir/$btype.1/created"
 298 fi