#!/bin/bash
#
# egrdbackup
#
# (c) 2006 Egressive Limited
# Backup script using rdiff-backup
# by rob@egressive.com 
# modified by dave@egressive.com 20060920
# modified rob@egressive.com 20061206 moved config items into seperate .conf file
#
## 
# Description - egrdbackup performs one task:
#  
#   Performs incremental backups of designated directory
#   hierarchy or backup set (minus any exclusions) into a designated
#   backup directory.
#
#   The current view of the data at any time will reflect the most
#   recent state of all the files in the backup set.  Diffs for 
#   older versions of all files are stored in hidden directories.
#   Older versions of any file can be recovered using rdiff-backup directly.
#
#   For example, to recover a backup of the directory (and contents) of
#   /home/operations from 4 days ago, where the backup directory is /backups, run: 
#
#   rdiff-backup -r 4D /backups/home/operations/ /home/operations/recovered-$(date "+%Y-%m-%d")
#  
##
#
# Default Settings
#
DEBUG=false
#
if [ $DEBUG == "true" ] ; then
   echo "Default Settings" 
fi
#
RDIFF_COMMAND=`which rdiff-backup`
MAIL_COMMAND=`which mail`
DF_COMMAND=`which df`
GREP_COMMAND=`which grep`
TAIL_COMMAND=`which tail`
NICE_COMMAND=`which nice`
HEAD_COMMAND=`which head`
CAT_COMMAND=`which cat`
DIRNAME_COMMAND=`which dirname`
BASENAME_COMMAND=`which basename`
MAIL_TO=root # temporary - overridden in CONF_FILE
#
#
#EGRD_ROOT=/etc/egscripts/egrdbackup
EGRD_ROOT=`$DIRNAME_COMMAND $0`
EGRD_SCRIPT=`$BASENAME_COMMAND $0`
# config file
CONF_FILE=$EGRD_ROOT/$EGRD_SCRIPT.conf
# name of file to run before and after rdiff-backup runs - for example an initial rsync or usb mount
INITIAL_CMD_FILE="initial.sh"
POST_CMD_FILE="postrun.sh"
#
INITIAL_CMD_FILE_OK="true"
#
# initialise end status
BACKUP_STATUS="[SUCCESS]"
#
# Get local configuration
#
if [ $DEBUG == "true" ] ; then
   echo "Get Local Settings" 
fi
if [ -x $CONF_FILE ] ; then
   . $CONF_FILE
else
   $CAT_COMMAND $LOGFILE | $MAIL_COMMAND -s "[ERROR] Could not find config file for $SERVERNAME backup" $MAIL_TO
   exit 1
fi
# logfile
LOGFILE=/var/log/$EGRD_LOGNAME.log # use logrotate to manage logs
#
#
##
if [ $DEBUG == "true" ] ; then
   echo "Remove Older versions" 
fi
#
#  You will need a --force the first time you run, or if you clear out the $RDIFF_DEST
# directory at any stage.  Probably safer not to use it normally. 
#
# check to see if the default rdiff revision directory is in place - if so, don't force
#
if [ "$RDIFF_FORCE" == "true" ] ; then
  RDIFF_FORCE_ARG=" --force "
fi
#
#
# If an initial command file exists (say to do an rsync first)
#
if [ -x $EGRD_ROOT/$INITIAL_CMD_FILE ] ; then
   . $EGRD_ROOT/$INITIAL_CMD_FILE
fi
#
if ! [ $INITIAL_CMD_FILE_OK == "true" ]
then
   BACKUP_STATUS="[ERROR]"
   BACKUP_ERROR=" | Error during initial setup"
   echo "Fatal error while running initial.sh"  >> $LOGFILE 2>> $LOGFILE
   $CAT_COMMAND $LOGFILE | $MAIL_COMMAND -s "$BACKUP_STATUS $SERVERNAME backup $BACKUP_ERROR" $MAIL_TO >> $LOGFILE 2>> $LOGFILE
   echo "Email sent to $MAIL_TO" >> $LOGFILE
   echo "Script complete"  >> $LOGFILE 2>> $LOGFILE
   echo "" >> $LOGFILE
   exit 1
fi

if test -d $RDIFF_DEST/rdiff-backup-data ; then
  if test -n $RDIFF_DAYS_OF_REVISIONS ; then
    #
    echo "++++++++++++++++++++++++++++++++++++++++++" >> $LOGFILE
    echo "   Deleting revisions older than $RDIFF_DAYS_OF_REVISIONS days " >> $LOGFILE
    echo "++++++++++++++++++++++++++++++++++++++++++" >> $LOGFILE
    # run delete command...
    echo "Running command:  $NICE_COMMAND $RDIFF_COMMAND --force --remove-older-than ${RDIFF_DAYS_OF_REVISIONS}D $RDIFF_DEST" >> $LOGFILE
    if ! $NICE_COMMAND $RDIFF_COMMAND --force --remove-older-than ${RDIFF_DAYS_OF_REVISIONS}D $RDIFF_DEST >> $LOGFILE 2>> $LOGFILE ; then 
       if ! $TAIL_COMMAND -2 $LOGFILE | $GREP_COMMAND "No increments older" > /dev/null 2>> $LOGFILE ; then
          BACKUP_STATUS="[ERROR]"
          BACKUP_ERROR=" | Error deleting revisions"
       fi
    fi
  fi
fi
#
##
ALL_RDIFF_EXCLUDES=""
if [ -n "$RDIFF_EXCLUDES" ] ; then 
   for i in $RDIFF_EXCLUDES ; do
      ALL_RDIFF_EXCLUDES=$ALL_RDIFF_EXCLUDES" --exclude $i "
   done
fi
#
# Start Rdiff-backup!
#
#  make sure log file exists
if [ $DEBUG == "true" ] ; then
   echo "Start backup" 
fi
touch $LOGFILE
DATE=`date`
echo "+++++++++++++++++++++++++++++++++++++++++++" >> $LOGFILE
echo "   Starting backup ($DATE) " >> $LOGFILE
echo "+++++++++++++++++++++++++++++++++++++++++++" >> $LOGFILE
echo "Running command: $NICE_COMMAND $RDIFF_COMMAND $RDIFF_ARGS $ALL_RDIFF_EXCLUDES $RDIFF_SRC $RDIFF_DEST " >> $LOGFILE
if ! $NICE_COMMAND $RDIFF_COMMAND $RDIFF_FORCE_ARG $RDIFF_ARGS $ALL_RDIFF_EXCLUDES $RDIFF_SRC $RDIFF_DEST \
          >> $LOGFILE 2>> $LOGFILE ; then
   echo "Error Code - rdiff-backup returned: $?" >> $LOGFILE
fi
if ! $TAIL_COMMAND -3 $LOGFILE | $GREP_COMMAND "Errors 0" > /dev/null 2>> $LOGFILE
then
     BACKUP_STATUS="[ERROR]"
     BACKUP_ERROR=$BACKUP_ERROR" | Error during backup"
fi
#
if [ $DEBUG == "true" ] ; then
   echo "=============================" 
   tail -10 $LOGFILE
   echo "=============================" 
fi
#
if [ $DEBUG == "true" ] ; then
   echo "Log and email out results" 
fi
#
echo "File system usage:" >> $LOGFILE
$DF_COMMAND -h >> $LOGFILE 2>> $LOGFILE
#
if [ $DEBUG == "true" ] ; then
   echo "Finish" 
fi
#
DATE=`date`
echo "+++++++++++++++++++++++++++++++++++++++++++" >> $LOGFILE
echo "   Completed backup ($DATE) " >> $LOGFILE
echo "+++++++++++++++++++++++++++++++++++++++++++" >> $LOGFILE
#
#
# If a post command file exists (say to unmount a usb drive)
#
if [ -x $EGRD_ROOT/$POST_CMD_FILE ] ; then
   .  $EGRD_ROOT/$POST_CMD_FILE
fi
#
$CAT_COMMAND $LOGFILE | $MAIL_COMMAND -s "$BACKUP_STATUS $SERVERNAME backup $BACKUP_ERROR" $MAIL_TO >> $LOGFILE 2>> $LOGFILE
echo "Email sent to $MAIL_TO" >> $LOGFILE
echo "Script complete"  >> $LOGFILE 2>> $LOGFILE
echo "" >> $LOGFILE