Shell Programming and Scripting

Hello,
I am trying to create an iptables script with tail ,sed and awk.

1st Request: Search keyword "secret" in access.log file
2nd Request: Get first column matching lines (ip address)
3rd Request: Save it to a file

This is what I did so far:

grep.sh

Code:

#!/bin/bash
while true;
do
tail -f /var/log/apache2/access.log | awk '{print $1}' 
#tail -f /var/log/apache2/access.log | grep --line-buffered secret | awk '/secret/' | awk '{print $1}'     #not working as expected
#tail -f /var/log/apache2/access.log | grep --line-buffered debug | awk '$1' > ip.txt                          #gives all lines but not column1
#echo "iptables -A INPUT -s "$1" -j DROP" >> black
#echo "$A" >> black
#chmod 755 black
#./black
done

It prints out all ip address but not searching for the keyword "secret".
When I clear shebang symbol existing at the beginning of the following lines, it does not print matching output.

Is it possible to assign the pipe output to a variable so that I can use that value in following steps for iptables command?

Thanks
Boris