Cookies from first principles - demonstration

State and Cookies example from a Well House Consultants training course
More on State and Cookies [link]

This example is described in the following article(s):
• Whisky - Setting and reading cookies from Perl - [link]

If you're searching for a page where you can run this program, select here

This example references the following resources:
http://www.wellho.net/resources/ex.php4?item=p407/whisky.pl
http://www.wellho.net/course/pwfull.html
http://www.wellho.net/

Source code: whisky.pl Module: P407

#!/usr/bin/env perl

# This uses non-persitant cookies, who's life is
# until the browser window is closed!

# Method ... no cookies, give a free drink;
# Already cookied - charge for another glass of the same!

# Has this user already had a type of whisky chosen?

# If not, pick up a random dusty bottle off the shelf
# and give him a free nip!

unless ($ENV{"HTTP_COOKIE"} =~ /highland=/)
{
srand;
chomp (@drinks = <DATA>);
$whisky = $drinks[rand($#drinks+1)];

# Make note of what you've given him so you can
# sell him his next drink ...

print "Content-type: text/html\n";
print "Set-Cookie: highland=$whisky;\n\n";
$response = "Welcome have a $whisky on the house";
$cookvar = "not defined";

} else {

# If, however, he's had a drink before look up
# which type (you can smell it on his breath, or
# rather in his cookie!)

@cookies=split(/;\s+/,$ENV{"HTTP_COOKIE"});
$cookvar = $ENV{"HTTP_COOKIE"};

foreach $cook(@cookies){
 ($name,$val)=split(/=/,$cook);
 $whisky = $val if ($name eq "highland");
 $kount = $val+1 if ($name eq "sofar");
}

# Look up how many he has had before and politely
# tell him how many and that he'll have to pay!

$kount = 2 if (! $kount);
print "Content-type: text/html\n";
print "Set-Cookie: sofar=",$kount,";\n\n";
$th = ("th","st","nd","rd",("th") x 6)[$kount%10];
$th = "th" if (($kount/10)%10 == 1);
$response = "ANOTHER $whisky? That's your $kount".$th.
 ". You have to pay this time!";
}
print <<"REP"
<html>
<head>
<title>A Whisky in the bar!</title></head>
<body bgcolor=white>
<h2>$response</h2>
Cookies and hidden fields may be used to maintain
state between a series of visits to a web site. This
example notes the first visit of a series and gives
the visitor a complimentary drink, then sells him
another drink of the same type on his second and
subsequent visits. Although this example is written
in Perl and uses the Common Gateway Interface (CGI),
we can also demonstrate the same capability using
PHP ... 
Cookie value: $cookvar; 
Cookie Demonstration from Well House Consultants 
• <a href=http://www.wellho.net/resources/ex.php4?item=p407/whisky.pl
>Source Code</a> 
• <a href=http://www.wellho.net/course/pwfull.html>Training Data</a> 
• <a href=http://www.wellho.net/>Home Page</a> 
</body>
</html>
REP
;
__END__
Bells
Johnnie_Walker
Teachers
Jack_Daniels
Grouse
Glenfiddich

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Other Examples

This example comes from our "State and Cookies" training module. You'll find a description of the topic and some other closely related examples on the "State and Cookies" module index page.

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