phpman > perldoc > CGI::Simple::Cookie(3pm)

NAME
    CGI::Simple::Cookie - Interface to HTTP cookies

SYNOPSIS
        use CGI::Simple::Standard qw(header);
        use CGI::Simple::Cookie;

        # Create new cookies and send them
        $cookie1 = CGI::Simple::Cookie->new( -name=>'ID', -value=>123456 );
        $cookie2 = CGI::Simple::Cookie->new( -name=>'preferences',
                                            -value=>{ font => Helvetica,
                                                      size => 12 }
                                          );
        print header( -cookie=>[$cookie1,$cookie2] );

        # fetch existing cookies
        %cookies = CGI::Simple::Cookie->fetch;
        $id = $cookies{'ID'}->value;

        # create cookies returned from an external source
        %cookies = CGI::Simple::Cookie->parse($ENV{COOKIE});

DESCRIPTION
    CGI::Simple::Cookie is an interface to HTTP/1.1 cookies, a mechanism that allows Web servers to
    store persistent information on the browser's side of the connection. Although
    CGI::Simple::Cookie is intended to be used in conjunction with CGI::Simple (and is in fact used
    by it internally), you can use this module independently.

    For full information on cookies see:

        http://tools.ietf.org/html/rfc2109
        http://tools.ietf.org/html/rfc2965

USING CGI::Simple::Cookie
    CGI::Simple::Cookie is object oriented. Each cookie object has a name and a value. The name is
    any scalar value. The value is any scalar or array value (associative arrays are also allowed).
    Cookies also have several optional attributes, including:

    1. expiration date
        The expiration date tells the browser how long to hang on to the cookie. If the cookie
        specifies an expiration date in the future, the browser will store the cookie information in
        a disk file and return it to the server every time the user reconnects (until the expiration
        date is reached). If the cookie species an expiration date in the past, the browser will
        remove the cookie from the disk file. If the expiration date is not specified, the cookie
        will persist only until the user quits the browser.

    2. domain
        This is a partial or complete domain name for which the cookie is valid. The browser will
        return the cookie to any host that matches the partial domain name. For example, if you
        specify a domain name of ".capricorn.com", then the browser will return the cookie to web
        servers running on any of the machines "www.capricorn.com", "ftp.capricorn.com",
        "feckless.capricorn.com", etc. Domain names must contain at least two periods to prevent
        attempts to match on top level domains like ".edu". If no domain is specified, then the
        browser will only return the cookie to servers on the host the cookie originated from.

    3. path
        If you provide a cookie path attribute, the browser will check it against your script's URL
        before returning the cookie. For example, if you specify the path "/cgi-bin", then the
        cookie will be returned to each of the scripts "/cgi-bin/tally.pl", "/cgi-bin/order.pl", and
        "/cgi-bin/customer_service/complain.pl", but not to the script "/cgi-private/site_admin.pl".
        By default, the path is set to "/", so that all scripts at your site will receive the
        cookie.

    4. secure flag
        If the "secure" attribute is set, the cookie will only be sent to your script if the CGI
        request is occurring on a secure channel, such as SSL.

    5. HttpOnly flag
        If the "httponly" attribute is set, the cookie will only be accessible through HTTP
        Requests. This cookie will be inaccessible via JavaScript (to prevent XSS attacks).

        See this URL for more information including supported browsers:

        <http://www.owasp.org/index.php/HTTPOnly>

    6. samesite flag
        Allowed settings are "Strict", "Lax" and "None".

        As of April 2018, support is limited mostly to recent releases of Chrome and Opera.

        <https://tools.ietf.org/html/draft-west-first-party-cookies-07>

  Creating New Cookies
        $c = CGI::Simple::Cookie->new( -name    =>  'foo',
                                      -value    =>  'bar',
                                      -expires  =>  '+3M',
                                      -max-age  =>  '+3M',
                                      -domain   =>  '.capricorn.com',
                                      -path     =>  '/cgi-bin/database',
                                      -secure   =>  1,
                                      -samesite =>  'Lax',
                                    );

    Create cookies from scratch with the new method. The -name and -value parameters are required.
    The name must be a scalar value. The value can be a scalar, an array reference, or a hash
    reference. (At some point in the future cookies will support one of the Perl object
    serialization protocols for full generality).

    -expires accepts any of the relative or absolute date formats recognized by CGI::Simple, for
    example "+3M" for three months in the future. See CGI::Simple's documentation for details.

    -max-age accepts the same data formats as -expires, but sets a relative value instead of an
    absolute like -expires. This is intended to be more secure since a clock could be changed to
    fake an absolute time. In practice, as of 2011, "-max-age" still does not enjoy the widespread
    support that "-expires" has. You can set both, and browsers that support "-max-age" should
    ignore the "Expires" header. The drawback to this approach is the bit of bandwidth for sending
    an extra header on each cookie.

    -domain points to a domain name or to a fully qualified host name. If not specified, the cookie
    will be returned only to the Web server that created it.

    -path points to a partial URL on the current server. The cookie will be returned to all URLs
    beginning with the specified path. If not specified, it defaults to '/', which returns the
    cookie to all pages at your site.

    -secure if set to a true value instructs the browser to return the cookie only when a
    cryptographic protocol is in use.

    -httponly if set to a true value, the cookie will not be accessible via JavaScript.

    -samesite may be "Lax", "Strict" or "None" and is an evolving part of the standards for cookies.
    Please refer to current documentation regarding it.

  Sending the Cookie to the Browser
    Within a CGI script you can send a cookie to the browser by creating one or more Set-Cookie:
    fields in the HTTP header. Here is a typical sequence:

        $c = CGI::Simple::Cookie->new( -name    =>  'foo',
                                       -value   =>  ['bar','baz'],
                                       -expires =>  '+3M'
                                      );

        print "Set-Cookie: $c\n";
        print "Content-Type: text/html\n\n";

    To send more than one cookie, create several Set-Cookie: fields. Alternatively, you may
    concatenate the cookies together with "; " and send them in one field.

    If you are using CGI::Simple, you send cookies by providing a -cookie argument to the header()
    method:

      print header( -cookie=>$c );

    Mod_perl users can set cookies using the request object's header_out() method:

      $r->header_out('Set-Cookie',$c);

    Internally, Cookie overloads the "" operator to call its as_string() method when incorporated
    into the HTTP header. as_string() turns the Cookie's internal representation into an
    RFC-compliant text representation. You may call as_string() yourself if you prefer:

        print "Set-Cookie: ",$c->as_string,"\n";

  Recovering Previous Cookies
        %cookies = CGI::Simple::Cookie->fetch;

    fetch returns an associative array consisting of all cookies returned by the browser. The keys
    of the array are the cookie names. You can iterate through the cookies this way:

        %cookies = CGI::Simple::Cookie->fetch;
        foreach (keys %cookies) {
            do_something($cookies{$_});
        }

    In a scalar context, fetch() returns a hash reference, which may be more efficient if you are
    manipulating multiple cookies.

    CGI::Simple uses the URL escaping methods to save and restore reserved characters in its
    cookies. If you are trying to retrieve a cookie set by a foreign server, this escaping method
    may trip you up. Use raw_fetch() instead, which has the same semantics as fetch(), but performs
    no unescaping.

    You may also retrieve cookies that were stored in some external form using the parse() class
    method:

           $COOKIES = `cat /usr/tmp/Cookie_stash`;
           %cookies = CGI::Simple::Cookie->parse($COOKIES);

  Manipulating Cookies
    Cookie objects have a series of accessor methods to get and set cookie attributes. Each accessor
    has a similar syntax. Called without arguments, the accessor returns the current value of the
    attribute. Called with an argument, the accessor changes the attribute and returns its new
    value.

    name()
        Get or set the cookie's name. Example:

            $name = $c->name;
            $new_name = $c->name('fred');

    value()
        Get or set the cookie's value. Example:

            $value = $c->value;
            @new_value = $c->value(['a','b','c','d']);

        value() is context sensitive. In a list context it will return the current value of the
        cookie as an array. In a scalar context it will return the first value of a multivalued
        cookie.

    domain()
        Get or set the cookie's domain.

    path()
        Get or set the cookie's path.

    expires()
        Get or set the cookie's expiration time.

    max_age()
        Get or set the cookie's maximum age.

    secure()
        Get or set the cookie's secure flag.

    httponly()
        Get or set the cookie's HttpOnly flag.

    samesite()
        Get or set the cookie's samesite value.

AUTHOR INFORMATION
    Original version copyright 1997-1998, Lincoln D. Stein. All rights reserved. Originally
    copyright 2001 Dr James Freeman <jfreeman AT tassie.au> This release by Andy Armstrong
    <andy AT hexten.net>

    This library is free software; you can redistribute it and/or modify it under the same terms as
    Perl itself.

    Address bug reports and comments to: andy AT hexten.net

BUGS
    This section intentionally left blank :-)

SEE ALSO
    CGI::Carp, CGI::Simple