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# 1  
Old 04-20-2010
Bash if else better way
I have a bash script which receives form posts with some search criteria to filter through a log file and echo the results.

I use the "if else" way to pint out only what matches from the form input. It works very well, but now I need to add another sting to search on and my list will double in size. I was wondering if there was a better way.
Code:
LOGFILE=`if [ $MONTH = "all" ] && [ $uid = "all" ] && [ $ROUTER = "all" ] ; then
nawk 'BEGIN {FS="\n"}{RS="#"}{print $0;}' tmp/command_tool.log
else
         if [ $MONTH = "all" ] && [ $uid = "all" ] && [ $ROUTER != "all" ] ; then
nawk 'BEGIN {FS="\n"}{RS="#"}{if ($0 ~ /'$ROUTER'/) print $0;}' tmp/command_tool.log
else
         if [ $MONTH = "all" ] && [ $uid != "all" ] && [ $ROUTER = "all" ] ; then
nawk 'BEGIN {FS="\n"}{RS="#"}{if ($3 ~ /'$uid'/) print $0;}' tmp/command_tool.log
else
         if [ $MONTH = "all" ] && [ $uid != "all" ] && [ $ROUTER != "all" ] ; then
nawk 'BEGIN {FS="\n"}{RS="#"}{if ($3 ~ /'$uid'/ && $5 ~ /'$ROUTER'/) print $0;}' tmp/command_tool.log
else
         if [ $MONTH != "all" ] && [ $uid != "all" ] && [ $ROUTER != "all" ] ; then
nawk 'BEGIN {FS="\n"}{RS="#"}{if ($2 ~ /^'$date'/ && $3 ~ /'$uid'/ && $5 ~ /'$ROUTER'/) print $0;}' tmp/command_tool.log
else
         if [ $MONTH != "all" ] && [ $uid = "all" ] && [ $ROUTER = "all" ] ; then
nawk 'BEGIN {FS="\n"}{RS="#"}{if ($2 ~ /^'$date'/) print $0;}' tmp/command_tool.log
else
         if [ $MONTH != "all" ] && [ $uid = "all" ] && [ $ROUTER != "all" ] ; then
nawk 'BEGIN {FS="\n"}{RS="#"}{if ($2 ~ /^'$date'/ && $5 ~ /'$ROUTER'/) print $0;}' tmp/command_tool.log
else
         if [ $MONTH != "all" ] && [ $uid != "all" ] && [ $ROUTER = "all" ] ; then
nawk 'BEGIN {FS="\n"}{RS="#"}{if ($2 ~ /^'$date'/ && $3 ~ /'$uid'/) print $0;}' tmp/command_tool.log
       fi
      fi
     fi
    fi
   fi
  fi
 fi
fi`

# 2  
Old 04-20-2010
nested if else can be written as..

Code:
if [..]; then
...
elif [..]; then
...
elif [..]; then
...
else
...
fi

# 3  
Old 04-20-2010
You did not provide any sample data on which to test, so the following is untested (though it should be semantically equivalent to your original post's code).

logsearch.awk:
Code:
BEGIN {FS="\n"; RS="#"}
m!="all" && index($2,d)!=1 {next}
u!="all" && index($3,u)==0 {next}
r!="all" && index($5,r)==0 {next}
{print}


Invocation:
Code:
nawk -f logsearch.awk d="$date" m="$MONTH" u="$UID" r="$ROUTER" tmp/command_tool.log

Just add new pattern-action pairs before the final print action in logsearch.awk, when it's time to add a new search field.

Regards,
Alister
Last edited by alister; 04-20-2010 at 03:14 PM..
# 4  
Old 04-20-2010
i would use binary logic to make a 3-bit variable
Code:
VAR=0
[ $MONTH = "all" ] && ((VAR+=4))
[ $uid = "all" ] && ((VAR+=2))
[ $ROUTER = "all" ] && ((VAR+=2))
case $VAR in
  7) EXPR="" ;;
  6) EXPR="0 ~ /'\$ROUTER'/" ;;
  5) EXPR="3 ~ /'\$uid'/" ;;
  4) EXPR="3 ~ /'\$uid'/ && \$5 ~ /'$ROUTER'/" ;;
  0) EXPR="2 ~ /^'\$date'/ && \$3 ~ /'\$uid'/ && \$5 ~ /'\$ROUTER'/" ;;
  3) EXPR="2 ~ /^'\$date'/" ;;
  2) EXPR="2 ~ /^'\$date'/ && \$5 ~ /'$ROUTER'/" ;;
  1) EXPR="2 ~ /^'\$date'/ && \$3 ~ /'\$uid'/" ;;
esac
# build the awk script
((VAR != 7)) && EXPR="if (\$$EXPR) "
LOGFILE=$( nawk -F "\n" "BEGIN {RS=\"#\"}{$EXPR print \$0;}" tmp/command_tool.log )

But i'm sure the awk code from alister is better...
It was just for the logic.
# 5  
Old 04-20-2010
Thanks alister, not sure how to implement your statements. Here is my entire script and a sample log.
Code:
#!/bin/sh
# Script which accepts input from logsearch.cgi and outputs Command Tool log
#
# The variables sent  in QUERY_STRING
ROUTER=`echo "$QUERY_STRING" | sed -n 's/^.*router=\([^&]*\).*$/\1/p'`
MONTH=`echo "$QUERY_STRING" | sed -n 's/^.*month=\([^&]*\).*$/\1/p'`
DAY=`echo "$QUERY_STRING" | sed -n 's/^.*day=\([^&]*\).*$/\1/p'`
TOOL=`echo "$QUERY_STRING" | sed -n 's/^.*tool=\([^&]*\).*$/\1/p'`
date="$MONTH$DAY"
uid=`echo "$QUERY_STRING" | sed -n 's/^.*uid=\([^&]*\).*$/\1/p'`
#
# Copy Command Tool log and remove blank lines and fold output to fit screen
cat /logs/command_tool.log | sed '/^$/d' | fold -s -w 120 >  tmp/command_tool.log
#
# Log file variable that searches the log depending on what is or is not matched
LOGFILE=`if [ $MONTH = "all" ] && [ $uid = "all" ] && [ $ROUTER = "all" ] ; then
nawk 'BEGIN {FS="\n"}{RS="#"}{print $0;}' tmp/command_tool.log
else
         if [ $MONTH = "all" ] && [ $uid = "all" ] && [ $ROUTER != "all" ] ; then
nawk 'BEGIN {FS="\n"}{RS="#"}{if ($0 ~ /'$ROUTER'/) print $0;}' tmp/command_tool.log
else
         if [ $MONTH = "all" ] && [ $uid != "all" ] && [ $ROUTER = "all" ] ; then
nawk 'BEGIN {FS="\n"}{RS="#"}{if ($3 ~ /'$uid'/) print $0;}' tmp/command_tool.log
else
         if [ $MONTH = "all" ] && [ $uid != "all" ] && [ $ROUTER != "all" ] ; then
nawk 'BEGIN {FS="\n"}{RS="#"}{if ($3 ~ /'$uid'/ && $5 ~ /'$ROUTER'/) print $0;}' tmp/command_tool.log
else
         if [ $MONTH != "all" ] && [ $uid != "all" ] && [ $ROUTER != "all" ] ; then
nawk 'BEGIN {FS="\n"}{RS="#"}{if ($2 ~ /^'$date'/ && $3 ~ /'$uid'/ && $5 ~ /'$ROUTER'/) print $0;}' tmp/command_tool.log
else
         if [ $MONTH != "all" ] && [ $uid = "all" ] && [ $ROUTER = "all" ] ; then
nawk 'BEGIN {FS="\n"}{RS="#"}{if ($2 ~ /^'$date'/) print $0;}' tmp/command_tool.log
else
         if [ $MONTH != "all" ] && [ $uid = "all" ] && [ $ROUTER != "all" ] ; then
nawk 'BEGIN {FS="\n"}{RS="#"}{if ($2 ~ /^'$date'/ && $5 ~ /'$ROUTER'/) print $0;}' tmp/command_tool.log
else
         if [ $MONTH != "all" ] && [ $uid != "all" ] && [ $ROUTER = "all" ] ; then
nawk 'BEGIN {FS="\n"}{RS="#"}{if ($2 ~ /^'$date'/ && $3 ~ /'$uid'/) print $0;}' tmp/command_tool.log
       fi
      fi
     fi
    fi
   fi
  fi
 fi
fi`
#
# The start of the html page
echo "Content-type: text/html"
echo ""
echo "<html>"
echo "<head>"
echo '<meta http-equiv="Content-Type" content="text/html; charset=utf-8">'
echo "<title>Log Search Results</title>"
echo "</head>"
echo '<body>'
echo '<table cellspacing="8" cellpadding="0" width="100%" height="100%"><tr><td valign="top">'
echo '<pre>'
echo "$LOGFILE"
echo '</pre></td></tr></table>'
echo '</body></html>'

Code:
#
03-26-2010 17:13:50
op8873
SUBMITTED FROM URL: tool9.cgi
CISCO1.APPLWI.NET
sh ver
#
03-26-2010 20:05:10
mm9909
SUBMITTED FROM URL: tool6.cgi
CISCO5.DALLAS.NET
show ip int brief 
show int loopback0
#
03-27-2010 20:06:20
kb3233
SUBMITTED FROM URL: tool6.cgi
CISCO2.DALLAS.NET
show port 1/1
show port
#
03-29-2010 20:14:49
gb2887
SUBMITTED FROM URL: tool9.cgi
CISCO1.AKRNOH.NET
cont local 
show port
#

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