#!/bin/ksh
# Author:  David Morris
# Version: $Id: shiplog.ksh,v 1.2 2004/11/05 20:50:48 davey Exp $
# Purpose: This script was designed to take care of tranferring Oracle
#          archive files to an offsite server. 
#          To run unattended (e.g. via cron) will need to make sure that 
#          you have SSH set to allow login via a key either with no password
#          or you have keys pre-loaded with the ssh-agent
#
# Notes:   PATH has to be set to include /usr/local/bin because if it's not
#          there then the commercial scp2 couldn't  seem to find ssh to call it.
#          (I think this may only be a problem for commercial ssh?)
#
# License: Released under the GNU Public Licence (GPL)
#          The terms of the GPL are available at:
#          http://www.gnu.org/licenses/gpl.html

export PATH=$PATH:/usr/local/bin
export DIRECTORY=/logfiles
# $ARCHIVEFILESPEC should be a pattern for the name of file
# that you want to ship. In this case we want to capture
# all files ending in .dbf:
export ARCHIVEFILESPEC='*.dbf'
export REMOTEHOST=server-01
export REMOTEDIRECTORY=/home/logtran/logfiles
export TIMESTAMPFILE=${DIRECTORY}/.TIMESTAMP
# The Cipher for Secure Shell to use:
export CIPHER=blowfish-cbc

#Commands: Change these paths as per your Operating System
export FIND=/usr/bin/find
export SCP=/usr/bin/scp
export SSH=/usr/bin/ssh
export LS=/bin/ls
export TOUCH=/bin/touch
export HOSTNAME=/usr/bin/hostname
export FUSER=/sbin/fuser
export TRUE=/bin/true
export false=/bin/false

function CheckSSH {
 # Check that we can reach the remotehost and execute a command
 $SSH $REMOTEHOST $HOSTNAME > /dev/null 2>&1
 RETCODE=$?
 if [ $RETCODE -eq 0 ]; then
  $TRUE
 else
  $FALSE
 fi
}

function TimeStamp {
 # This is the heart of what this script does:
 # If there isn't a $TIMESTAMP file already then create one with 
 # date at the unix epoch. The $TIMESTAMP file is used as a
 # placemarker, when a file, 'logfile.dbf' is successfully transferred, the timestamp
 # file is updated with the timestamp of 'logfile.dbf' 
 # 
 if [[ ! -f $TIMESTAMPFILE ]]; then
   $TOUCH -t 197001010000 $TIMESTAMPFILE || {
   print -u2 "ERROR: Cannot create $TIMESTAMPFILE"
   exit 1
  }
 fi
}

function CreateArchiveList {
 # Uses the find command to generate a list of files newer than the timestamp file
 # i.e., ones that need to be processed and in this case delivered to the remote host.
 if [ -d $DIRECTORY ] ; then
  $FIND $DIRECTORY/ -name $ARCHIVEFILESPEC -newer $TIMESTAMPFILE 2>/dev/null
 else
  print -u2 "ERROR $?: cannot find $DIRECTORY"
  exit 1
 fi
}

function ExcludeOpenFiles {
# We don't want to send a file which is currently open, because it will be incomplete.
while read FILENAME
do
 if [[ -n "$($FUSER $FILENAME 2>/dev/null)" ]] ; then
  print -u2 "WARNING: file $FILENAME is in use skipping"
  # We don't need an alert for skipped files
 else
  print $FILENAME
 fi
done
}

function ProcessArchiveList {
while read FILENAME
do
 $SCP -B -p -c $CIPHER  $FILENAME $REMOTEHOST:$REMOTEDIRECTORY
 RETCODE=$?
 if [ $RETCODE -eq 0 ]; then
  print -u1 $FILENAME transferred successfully
  # now update the $TIMESTAMP placeholder to make CreateArchiveList
  # pick up only newer files than this on the next run:
  $TOUCH -r $FILENAME $TIMESTAMPFILE 
 else
  print -u2 ERROR ${RETCODE}: $FILENAME failed to transfer
 fi
done

}

# Shell Logic: Call the functions 
# First check if SSH can connect to the remote system:
CheckSSH
if [ $? -eq 0 ]; then
 TimeStamp
 CreateArchiveList | ExcludeOpenFiles | ProcessArchiveList
else
 print -u2 "Could not establish SSH connection with $REMOTEHOST"
fi