Run linux script on received emails

I have written a small little script that looks up a work on wikipedia and then prints the result to the command line. I want to be able to email that word to my server and then have my server email me the results back.

So far I have a new user named 'wiki' where the e-mails are being sent to. I am receiving the e-mails fine. In /etc/aliases I have redirected incoming emails开发者_JAVA技巧 to my script I wrote.

# See man 5 aliases for format
wiki: "|/home/wiki/scripts/wiki"

That works fine.

My script works find from the command line, as if i typed

$ ./wiki <whatever>

I get permission denied errors when I sent an email to wiki@mydomain.com

My wiki script permissions are:

 -rwxr-xr-x 1 wiki wiki  427 2011-04-18 22:54 wiki

What is wrong! What permissions do I need to set? Any help is appreciated.

EDIT (4/18/11 8:20pm): This is my script.

#!/bin/bash

read MSG
echo $MSG >> "newfile"
FROM=$(echo "$MSG" | cut -d " " -f2)
DATA=$(echo "$MSG" | cut -d " " -f3)
if [ MSG ]
then
RTN=`nslookup -q=txt $DATA.wp.dg.cx | grep "text =" | cut -d"=" -f2`

echo $RTN | sendmail -s "wikipedia: '$DATA'" $FROM

else
echo  wilkipedia nslookup. Please supply a command line argument.
fi

Depending on you mailserver (e.g. postfix) you may need to configure it to allow piping mail. Most often, using ~/.procmailrc is easiest.

This is what I did to take care of my problem...

1. I scrapped my bash script, and wrote the same function in python. I used python because of its email parsing functionality. I also ran the user input through some string escape prevention code so that I could safely hand it off to python's subprocess.popen() method.

2. I was trying to write the stdin to a local file so I could see where to parse the text, however the mail application (mail or postfix, not sure) doesn't have permissions to write files - Prob a good thing in the end. To debug, I just returned the raw stdin (email header and all) in a string and emailed it back to myself to see what was going on.

3. I set /etc/aliases to read

   wiki: "|/home/wiki/scripts/wiki.py"

4. permissions on wiki.py are

   4 -rw-r--r-- 1 wiki mail 1902 2011-04-19 21:04 wiki.py

   and this way the mail program successfully hands it off to your script. You can also go check "/var/log/mail.log" for output if you have errors in your script and nothing gets emailed back to you. If the mail reached the script, but error-ed out because of syntax or a bug, you should get an email reply from MAILER-DAEMON stating that it was undeliverable.

5. I didn't use procmail or have a .procmailrc file. /etc/aliases worked just fine. It passes your e-mail to the stdin stream, and in python try this:

extra="" while 1: line = sys.stdin.readline() if not line: break extra = extra + line.strip(" ")