egscripts/egbackup/egbackup

#!/bin/bash
#
# egbackup, copyright 2005 egressive limited, www.egressive.com
#
# this script runs a series of daily backup files, one after another
#
#==========================================
# The Variables - these must be define
#   before they're referenced
#==========================================
VERSION="0.1"
#EGBU_DIR=/etc/egscripts/egbackup
EGBU_NAME=`basename $0`
#echo $EGBU_NAME
EGBU_DIR=/etc/egscripts/egbackup
EGBU_CMD=$EGBU_DIR/egbackup
EGBU_CONF_DIR=$EGBU_DIR/conf
SITE_CONF=$EGBU_CONF_DIR/site.conf
BU_EXCLUDES=$EGBU_CONF_DIR/.excludes
#
# this provides values for MACHINE_NAME and EMAIL
. $SITE_CONF
#
LOGS=/var/log
LOG=$LOGS/egbackup.log
# required programs
MAIL=`which mail`
GREP=`which grep`
LS=`which ls`
ID=`which id`
DATE=`which date`
DF=`which df`
GZIP=`which gzip`
RM=`which rm`
LN=`which ln`
CUT=`which cut`
TOUCH=`which touch`
# determine today's date
TODAY=`$DATE '+%Y-%m-%d-%a'`
# determine today's date
NOW=`$DATE '+%H-%M-%S'`
# a timestamp for logging purposes
TIMESTAMP=`$DATE '+%Y-%m-%d %H:%M.%S'`
# temporary holding point for email
TMP_DIR=/tmp
TMP_EMAIL=$TMP_DIR/$EGBU_NAME"_tmp_email_"$TODAY.$TIME
#
# for pruning old backups
#
# build list of possible pruning candidates
BU_SUFFIX="tgz"
LIST_SUFFIX="list"
#
# tar command
TAR=`which tar`
# tar command options
# c = create
# v = verbose (for the purpose of recording a list of files)
# f = save to file rather than pipe
# z = compress with gzip
# W = verify archive against file system on completion
#FLAGS=" cvfzW "
FLAGS=" cvfz  "
# wc (word count) command
WC=`which wc`
# awk command
AWK=`which awk`
#  don't worry, this is just used to determine if the
#  disk is installed - it's not going to change the partition table!
FDISK=`which fdisk`
#
#==========================================
#  The Functions - these have to be defined
#    before they're called!  Note, refer
#   to them without the "()" and provide
#   up to one argument, referred to as "$@"
#   in the function...
#==========================================
#
# function to direct a message...
message() {
  #
  # a timestamp for logging purposes
  timestamp
  if test -w $LOG ; then
    echo "$EGBU_NAME: $TIMESTAMP $@" >> $LOG
  fi
  if test -w $TMP_EMAIL ; then
    echo "$EGBU_NAME: $TIMESTAMP $@" >> $TMP_EMAIL
  fi
  verbose "$TIMESTAMP $@"
}
#
# function to direct a message...
verbose() {
  if test $VERBOSE ; then
    echo "$@"
  fi
}
#
# insert a blank line into the log and on the console
insert_blank() {
  echo "" >> $TMP_EMAIL
  verbose ""
}
#
# update date and time info..
today() {
  # determine today's date
  TODAY=`$DATE '+%Y-%m-%d-%a'`
}
now() {
  # determine today's date
  NOW=`$DATE '+%H-%M-%S'`
}
timestamp() {
  # a timestamp for logging purposes
  TIMESTAMP=`date  '+%Y-%m-%d %H:%M.%S'`
}
#
# create the temporary email file
create_tmp_email() {
  if test -d $TMP_DIR ; then
    if test -w $TMP_DIR ; then
      touch $TMP_EMAIL 2>&1
    else
      error "Email tmp directory $TMP_DIR is not writable"
    fi
  else
    error "Email tmp directory $TMP_DIR does not exist"
  fi
  
  if test -w $TMP_EMAIL ; then
    message "created temporary email $TMP_EMAIL"
  else
    error "Failed to create temporary email $TMP_EMAIL"
  fi
}
#
# send the contents of the temporary file to the
# designated report recipient
send_email_report() {
  if test -f $TMP_EMAIL ; then
    message "sending email report to $EMAIL_TO"
    if test $ERROR_STATUS == 1 ; then
      EMAIL_SUBJ="[ERROR] $MACHINE_NAME Backup - $PERIOD"
    else
      EMAIL_SUBJ="[SUCCESS] $MACHINE_NAME Backup Report - $PERIOD"
    fi
    # check space again to see how close things are to full
    
    message "Printing disk space for reference purposes:"
    DISK_SPACE=`$DF`
    message "$DISK_SPACE"
    # send it to each email address in the list...
    for EMAIL_ADD in $EMAIL_TO
    do
      RES=`$MAIL -s "$EMAIL_SUBJ" $EMAIL_ADD < $TMP_EMAIL`
      if test -z $RES ; then
        if test $ERROR_STATUS == 1 ; then
          message "Error email report successfully sent to $EMAIL_ADD"
        else
          message "Email report successfully sent to $EMAIL_ADD"
        fi
      else
        if ! test $ERROR_STATUS == 1 ; then
          error "Email report send to $EMAIL_ADD failed with this message: $RES"
        fi
      fi
    done
    if test -w $TMP_EMAIL ; then
      $RM $TMP_EMAIL 2>&1
    else
      if ! test $ERROR_STATUS == 1 ; then
        error "Failed to remove email message file, $TMP_EMAIL: permission denied."
      fi
    fi
    if test -f $TMP_EMAIL ; then
      error "Failed to remove email message file $TMP_EMAIL for an unknown reason"
    else
      message "successfully removed temporary email  $TMP_EMAIL"
    fi
  else
    if ! test $ERROR_STATUS == 1 ; then
      error "Email message file, $TMP_EMAIL, does not exist."
    fi
  fi
}
#
#  build list of backup configuration files
get_confs() {
  CONFS=`$LS -1 $EGBU_CONF_DIR/$CONF_ROOT*.conf 2>&1`
  TEST=`echo $CONFS | $GREP -c "No such file or directory" -`
  #TEST2=`echo $CONFS | $GREP -c "$EGBU_CONF_DIR" -`
  if test $TEST == 1 ; then
    error "No configuration files found with root $CONF_ROOT in $EGBU_CONF_DIR"
  fi
  #echo "CONFS = $CONFS"
}
#
# function to direct an error...
error() {
  #
  # recognise that the system experienced
  # an error and send out a special email, and halt
  # the program!
  timestamp
  ERROR_STATUS=1
  #
  # get current user details
  USER_DETAILS=`$ID`
  if test -w $LOG ; then
    echo "$EGBU_NAME: **ERROR** $TIMESTAMP $@" >> $LOG
    echo "$EGBU_NAME: user details - $USER_DETAILS" >> $LOG
  fi
  if test -w $TMP_EMAIL ; then
    echo "$EGBU_NAME: **ERROR** $TIMESTAMP $@" >> $TMP_EMAIL
    echo "  user details: $USER_DETAILS" >> $LOG
  fi
  verbose "$TIMESTAMP **ERROR** $@"
  verbose "  user details: $USER_DETAILS"
  send_email_report
  exit 1   
}
#
# build excludes list
build_excludes() {
  message "building excludes"
  # the following is required to avoid expanding wildcards...
  # see man bash, search on GLOBIGNORE, for more info
  GLOBIGNORE=*
  if test -f $BU_EXCLUDES ; then 
    rm $BU_EXCLUDES
  fi
  $TOUCH $BU_EXCLUDES
  for PAT in $EXCLUDE
  do
    echo $PAT >> $BU_EXCLUDES
  done
  echo "*/$NO_BACKUP_DIR/*" >> $BU_EXCLUDES

#  EXCLUDES=
#  for PAT in $EXCLUDE
#  do
#    EXCLUDES="$EXCLUDES --exclude=\"$PAT\""
#  done
#  EXCLUDES="$EXCLUDES --exclude=\"*/$NO_BACKUP_DIR\""
#
#  echo */$NO_BACKUP_DIR >> $EXCLUDES_FILE

  # also required - see above
  GLOBIGNORE=
  #echo "Excludes = $EXCLUDES"
}
#
# delete old backups
delete_old() {
  #
  if test -n $BU_FROOT && test -n $BU_TO_KEEP ; then
    # pattern to search for to build the list...
    PATTERN="$BU_DIR/$BU_FROOT.*"
    # build the list, with the suffix...
    PRUNEABLES=`$LS -1t $PATTERN.$BU_SUFFIX 2>&1`
    #echo "PRUNEABLES=$PRUNEABLES"
    TEST=`echo $PRUNEABLES | $GREP -c "No such file or directory" -`
    if ! test $TEST == 1 ; then
      message "pruning older files based on $PATTERN.$BU_SUFFIX"
      message "keeping last $BU_TO_KEEP backups"
      #
      # set counter
      NUM=0
      # go through the list of files and remove those we don't want
      for PRUNEABLE in $PRUNEABLES
      do
        NUM=$(($NUM + 1))
        if test $NUM -gt $BU_TO_KEEP ; then
          message "deleting $PRUNEABLE and associated list files"
          BASE=`basename $PRUNEABLE .$BU_SUFFIX`
          if test $DRY_RUN == 1 ; then
            message "would delete $BU_DIR/$BASE.$BU_SUFFIX and associated list file"
            else
            if [ -e "$BU_DIR/$BASE.$BU_SUFFIX" ]; then
              $RM $BU_DIR/$BASE.$BU_SUFFIX 2>&1
            elif [ -e "$BU_DIR/$BASE.$LIST_SUFFIX" ]; then
              $RM $BU_DIR/$BASE.$LIST_SUFFIX 2>&1
            elif [ -e "$BU_DIR/$BASE.$LIST_SUFFIX.gz" ]; then
              $RM $BU_DIR/$BASE.$LIST_SUFFIX.gz 2>&1
            fi
          fi
        else
          message "keeping $PRUNEABLE"
        fi
      done
    else
      message "no pruneable files found based on pattern: $PATTERN.$BU_SUFFIX"
    fi
  else 
    message "keeping older backups, missing backup_root_filename..."
  fi
}
#
#
check_space() {
  RES=`$DF -h`
  #message "$RES"
  TEST=0
  PCENT="100%"
  TEST=`echo "$RES" | $GREP -c "$PCENT"`
  if test $TEST == 1  ; then
    PART_LINE=`echo "$RES" | $GREP "$PCENT"`
    # get the device name which is showing $PCENT
    TEST=`echo $PART_LINE | $CUT -f 1 -d ' '`
    # if it has a partition number in the name, it's probably a block
    # device rather than, say, a CDROM...
    TEST2=`echo $TEST | $GREP -c [0-9]`
    echo "Test2 = $TEST2"
    if test $TEST2 == 1 ; then
      error "Partition $TEST is full - detail: $PART_LINE"
    else
      message "false alarm - it's only the $TEST volume..."
    fi
  fi
}
#
#  this is where we do all the backup-related stuff - what ebu used to do...
do_backup() {
  #
  # set up filenames for backup files
  today  # update date stamp
  now  # update time stamp
  BU_FILE="$BU_FROOT.$TODAY.$NOW.$BU_SUFFIX"
  BU_LIST="$BU_FROOT.$TODAY.$NOW.$LIST_SUFFIX"
  message "will create backup files: $BU_FILE, $BU_LIST"
  #
  delete_old  # delete old backups
  check_space  # see how much space is left in backup area
  build_excludes  # build list of files to exclude
  BU_CONF_NAME=`basename $BU_CONF`
  #echo "CURRENT_LINK = $CURRENT_LINK"
  if test -d $BU_DIR ; then
    if ! test -w $BU_DIR ; then
      error "Backup directory, $BU_DIR, not writable"
    fi
  else
    error "Backup directory, $BU_DIR, doesn't exist"
  fi
  #BU_CMD="nice -n $NICE $TAR $FLAGS $BU_DIR/$BU_FILE $EXCLUDES $FILES"
  BU_CMD="nice -n $NICE $TAR $FLAGS $BU_DIR/$BU_FILE -X $BU_EXCLUDES $FILES"
  #echo "DR=$DRY_RUN"
  if test $DRY_RUN == 1 ; then
    message "dry run, not doing backup"
    message "if we were, we'd run $BU_CMD"
  else
    if test ! $CURRENT_LINK = "none" ; then
      message "removing link: $BU_DIR/$CURRENT_LINK"
      # first remove any existing link
      if [ -h "$BU_DIR/$CURRENT_LINK.$BU_SUFFIX" ]; then
        $RM $BU_DIR/$CURRENT_LINK.$BU_SUFFIX 2>&1
      fi
    fi
    message "Executing backup command: $BU_CMD"
    RES=`echo $GLOBIGNORE > $BU_DIR/$BU_LIST; $BU_CMD >> $BU_DIR/$BU_LIST`
    if test "$?" -ne "0" ; then
      message "-------Backup ended with error, error: $? ----------"
      error "TAR EXIT CODE: $?"
    else
      message "+++++++Backup $BU_FILE successfully finished++++++++"
      NUM_FILES=`$WC $BU_DIR/$BU_LIST | $AWK '{print $1}'`
      message "Backed up $NUM_FILES files..."
      BYTES=`$LS -l $BU_DIR/$BU_FILE | $AWK '{print $5;}'`
      KBYTES=$(($BYTES/1024))
      MBYTES=$(($KBYTES/1024))
      message "Backup size: $MBYTES MB ($KBYTES K)"
#      echo "success: $NUM_FILES backed up $NUM_FILES in $MBYTES MB ($KBYTES K)" > $STAT_DIR/$NAME-$BU_CONF_NAME
      # if the variable $CURRENT_LINK is defined in the .conf file, make
      # a link to it.
      if test ! $CURRENT_LINK = "none" ; then
        message "Linking $BU_DIR/$CURRENT_LINK to $BU_DIR/$BU_FILE..."
        # create a new link to the current archive
        RES=`$LN -f $BU_DIR/$BU_FILE $BU_DIR/$CURRENT_LINK.$BU_SUFFIX 2>&1`
        if test "$?" -ne "0" ; then
          error "Linking $BU_DIR/$BU_FILE to $BU_DIR/$CURRENT_LINK.$BU_SUFFIX failed"
        fi
      fi
      if test -f "$BU_DIR/$BU_LIST.gz" ; then
        $RM $BU_DIR/$BU_LIST.gz
      fi
      $GZIP $BU_DIR/$BU_LIST
    fi
  fi
}
#========================================
#  The Error Checking
#========================================
#
# first, check that all the necessary files and stuff are there and usable
#
# if the log doesn't exist, create it
if ! test -f $LOG ; then
  message "creating non-existent log file $LOG"
  RET=`touch $LOG 2>&1 /dev/null`
  TEST=`echo $RET | $GREP -c "Permission denied" -`
  if test $TEST == 1 ; then
    error "Failed to create log file $LOG, user cannot write to that directory"
  fi
fi
# checking whether it's there an is writable
if ! test -w $LOG ; then
  error "Log file $LOG not writable"
fi

#========================================
#  The Functional Part of the Script
#========================================
#  set variable defaults
ERROR_STATUS=0  # initially assume no errors
VERBOSE=0  # initially assume quiet output
CONF_ROOT=1 # set it to something we know so we can test if it's changed
DRY_RUN=0 # assume this is not a dry run...
CURRENT_LINK="none"
MODE=help
#  process any arguments
while test $# -ne 0 ; do  # while there are arguments
  message "argument: $1"
  case $1 in
    --verbose|-v)
      verbose "setting verbostity to ON"
      VERBOSE=1
      ;;
    --dryrun)
      verbose "setting dryrun to ON"
      DRY_RUN=1
      ;;
    *)
      TEST=`echo $1 | $GREP -c '-'`
      if ! test $TEST == 1 ; then
        CONF_ROOT=$1
        PERIOD=$CONF_ROOT
      fi
      ;;
   esac
   shift
done 
if test $CONF_ROOT == 1 ; then
  MODE=help
  verbose "showing help, because we didn't get a CONF_ROOT value"
else
  MODE=run
fi
#
#  set things in motion based on the script arguments
case $MODE in
  run)
    create_tmp_email
    get_confs
    #  run backup for each file
    for BU_CONF in $CONFS
    do
      message "do backup with conf: $BU_CONF"
      . $BU_CONF  # grab the current variables for this conf file...
      do_backup
      # put a space in the email to separate tasks
      insert_blank
    done
    #
    #  send the resulting email
    send_email_report
    ;;
  help)
    if test $CONF_ROOT; then
      echo "error: please specify a period for egbackup"
    fi
    echo ""
    echo "$EGBU_NAME, version $VERSION, copyright 2005 Egressive Ltd, www.egressive.com"
    echo "==================="
    echo "usage: $EGBU_NAME period"
    echo " where 'period' is one of hourly, daily, weekly, monthly, yearly, etc."
    echo " corresponding to named configurations, e.g. daily-backup.conf, in the "
    echo " conf dir, currently set to $EGBU_CONF_DIR"
    echo "== other options =="
    echo "-v or --verbose -  give extra feedback on progress to stdout"
    echo "-c or --configroot config_filename - root for configuration filenames"
    echo "--dryrun - do everything else, but *don't* delete anything or run the backup"
    echo ""
  ;;
esac

exit 0