rikijpn's blog: cgi

Showing posts with label cgi. Show all posts

Sunday, July 24, 2011

getting variables from GET method in perl (cgi)

Suppose we have a page with the following form:

<form action="index.pl" method="get">
<input type="text" name="search_for" size="30" />
<input type="submit" value="search" />
</form>

So, there's a text input field named "search_for", and a submit button.
The following code gets the variables set in QUERY_STRING (whatever is after pagename.pl?...), into the $arg associative array. So we can get the value of "search_for" by $arg{"search_for"}.

for (split /\&/, $ENV{QUERY_STRING}) {
($key,$val) = split /\=/;
$val =~ s/\+/ /g;
$val =~ s/%([0-9a-fA-F]{2})/chr(hex($1))/ge;
$arg{$key} = $val;
}
print "data searched for is =
$arg{search_for}
";

Friday, July 22, 2011

apache cgi enabled site on specific dir

As an example, using /home/username/some_test_dir/, although it's obviously better not to use home dirs for this kind of things.

These settings allow you to access the files in /home/username/some_test_dir on the web by localhost/some_web_dir (set in alias).
And also enables you to run cgi scripts there.
In the shell:

a2enmod cgi #enable cgi
a2ensite site-filename
/etc/init.d/apache2 reload #in debian

Where filename, is the name of a file containing the following text, placed in /etc/apache2/sites-available/:

<VirtualHost *:80>
 ServerAdmin this_is_my_name@my_test_domain.com

 DocumentRoot /home/username/some_test_dir/
 <Directory "/home/username/some_test_dir">
  AllowOverride None
  Options +ExecCGI -MultiViews +SymLinksIfOwnerMatch
                Order allow,deny
         allow from all
                AddHandler cgi-script .cgi .pl .sh
 </Directory>
        Alias /some_web_dir "/home/username/some_test_dir/"

 ErrorLog ${APACHE_LOG_DIR}/some_web_dir_error.log

 # Possible values include: debug, info, notice, warn, error, crit,
 # alert, emerg.
 LogLevel warn

 CustomLog ${APACHE_LOG_DIR}/some_web_dir_access.log combined
</VirtualHost>

simple cgi shell script

You just print out an html page. The only other thing you have to care about is outputting:
Content-type: text/html

(followed by two newlines characters)
And then, as long as your apache settings are working and the file has executable permission (chmod a+x filename), your browser should display the proper page.

#!/bin/sh
#you need this part for cgi handling
printf "Content-type: text/html\n\n"

# contents
echo "<html>"
echo "<head><title>Dude</title></head>"
echo "<body>"
echo "<h1>some header</h1>"
echo "awesome"
echo "</body>"
echo "</html>"