/ 
Data-Validate-Domain-0.03
River stage two • 13 direct dependents • 54 total dependents
/ Data::Validate::Domain

NAME

Data::Validate::Domain - domain validation methods

SYNOPSIS

use Data::Validate::Domain qw(is_domain);

if(is_domain($suspect)){
      print "Looks like a domain name";
} else {
      print "Not a domain name\n";
}


# or as an object
my $v = Data::Validate::Domain->new();

die "not a domain" unless ($v->is_domain('domain.com'));

DESCRIPTION

This module collects domain validation routines to make input validation, and untainting easier and more readable.

All functions return an untainted value if the test passes, and undef if it fails. This means that you should always check for a defined status explicitly. Don't assume the return will be true. (e.g. is_username('0'))

The value to test is always the first (and often only) argument.

FUNCTIONS

    new - constructor for OO usage

    $obj = Data::Validate::Domain->new();
    Description

    Returns a Data::Validator::Domain object. This lets you access all the validator function calls as methods without importing them into your namespace or using the clumsy Data::Validate::Domain::function_name() format.

    Arguments

    None

    Returns

    Returns a Data::Validate::Domain object

    is_domain - does the value look like a domain name?

    is_domain($value);
or
$obj->is_domain($value);
    Description

    Returns the untainted domain name if the test value appears to be a well-formed domain name.

    Arguments
    $value

    The potential domain to test.

    Returns

    Returns the untainted domain on success, undef on failure.

    Notes, Exceptions, & Bugs

    The function does not make any attempt to check whether a domain actually exists. It only looks to see that the format is appropriate.

    A dotted quad (such as 127.0.0.1) is not considered a domain and will return false. See Data::Validate::IP(3) for IP Validation.

    Performs a lookup via Net::Domain::TLD to verify that the TLD is valid for this domain.

    Does not consider "domain.com." a valid format.

    From RFC 952
    A "name" (Net, Host, Gateway, or Domain name) is a text string up
to 24 characters drawn from the alphabet (A-Z), digits (0-9), minus
sign (-), and period (.).  Note that periods are only allowed when
they serve to delimit components of "domain style names".

 No blank or space characters are permitted as part of a
name. No distinction is made between upper and lower case.  The first
character must be an alpha character [Relaxed in RFC 1123] .  The last 
character must not be a minus sign or period.
    From RFC 1035
    labels          63 octets or less
names           255 octets or less

[snip] limit the label to 63 octets or less.

To simplify implementations, the total length of a domain name (i.e.,
label octets and label length octets) is restricted to 255 octets or
less.
    From RFC 1123
    One aspect of host name syntax is hereby changed: the
restriction on the first character is relaxed to allow either a
letter or a digit.  Host software MUST support this more liberal
syntax.

Host software MUST handle host names of up to 63 characters and
SHOULD handle host names of up to 255 characters.

    is_hostname - does the value look like a hostname

    is_hostname($value);
or
$obj->is_hostname($value);
    Description

    Returns the untainted hostname if the test value appears to be a well-formed hostname.

    Arguments
    $value

    The potential hostname to test.

    Returns

    Returns the untainted hostname on success, undef on failure.

    Notes, Exceptions, & Bugs

    The function does not make any attempt to check whether a hostname actually exists. It only looks to see that the format is appropriate.

    Functions much like is_domain, except that it does not verify whether or not a valid TLD has been supplied and allows for there to only be a single component of the hostname (i.e www)

    Hostnames might or might not have a valid TLD attached.

    is_domain_label - does the value look like a domain label?

    is_domain_label($value);
or
$obj->is_domain_label($value);
    Description

    Returns the untainted domain label if the test value appears to be a well-formed domain label.

    Arguments
    $value

    The potential ip to test.

    Returns

    Returns the untainted domain label on success, undef on failure.

    Notes, Exceptions, & Bugs

    The function does not make any attempt to check whether a domain label actually exists. It only looks to see that the format is appropriate.

SEE ALSO

[RFC 1034] [RFC 1035] [RFC 2181] [RFC 1123]

Data::Validate(3)
Data::Validate::IP(3)

AUTHOR

Neil Neely <neil@frii.net>.

ACKNOWLEDGEMENTS

Thanks to Richard Sonnen <sonnen@richardsonnen.com> for writing the Data::Validate module.

COPYRIGHT AND LICENSE

Copyright (c) 2005 Neil Neely.

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.8.2 or, at your option, any later version of Perl 5 you may have available.

2 POD Errors

The following errors were encountered while parsing the POD:

Around line 68:

You can't have =items (as at line 76) unless the first thing after the =over is an =item

Around line 366:

You forgot a '=back' before '=head1'