Data::Validate::Domain - Domain and host name validation
version 0.15
use Data::Validate::Domain qw(is_domain);
# as a function
my $test = is_domain($suspect);
die "$test is not a domain" unless $test;
# or
die "$test is not a domain" unless is_domain($suspect, \%options);
# or as an object
my $v = Data::Validate::Domain->new(%options);
die "$test is not a domain" unless $v->is_domain($suspect);
This module offers a few subroutines for validating domain and host names.
All of the functions below are exported by default.
All of the functions return an untainted value on success and a false value
(undef or an empty list) on failure. In scalar context, you should check
that the return value is defined, because something like
is_domain_label('0') will return a defined but false value.
The value to test is always the first (and often only) argument.
Note that none of these functions test whether a domain or hostname is actually resolvable or reachable.
This method constructs a validation object. It accepts the following arguments:
-
domain_allow_underscore
According to RFC underscores are forbidden in hostnames but not domain names. By default
is_domain(),is_domain_label(), andis_hostname()will fail if the value to be checked includes underscores. Setting this to a true value will allow the use of underscores in all functions. -
domain_allow_single_label
By default
is_domain()will fail if you ask it to verify a domain that only has a single label i.e. "neely.cx" is good, but "com" would fail. If you set this option to a true value thenis_domain()will allow single label domains through. This is most likely to be useful in combination with thedomain_private_tldargument. -
domain_disable_tld_validation
Disables TLD validation for
is_domain(). This may be useful if you need to check domains with new gTLDs that have not yet been added to Net::Domain::TLD. -
domain_private_tld
By default
is_domain()requires all domains to have a valid public TLD (i.e. com, net, org, uk, etc). This is verified using the Net::Domain::TLD module. This behavior can be extended in two different ways. You can provide either a hash reference where additional TLDs are keys or you can supply a regular expression.NOTE: The TLD is normalized to the lower case form prior to the check being done. This is done only for the TLD check, and does not alter the output in any way.
Hashref example:
domain_private_tld => { privatetld1 => 1, privatetld2 => 1, }Regular expression example:
domain_private_tld => qr /^(?:privatetld1|privatetld2)$/,
This can be called as either a subroutine or a method. If called as a sub, you can pass any of the arguments accepted by the constructor as options. If called as a method, any additional options are ignored.
This returns the untainted domain name if the given $domain is a valid
domain.
A dotted quad (such as 127.0.0.1) is not considered a domain and will return false. See Data::Validate::IP for IP Validation.
Per RFC 1035, this sub does accept a value ending in a single period (i.e.
"domain.com.") to be a valid domain. This is called an absolute domain name,
and should be properly resolved by any DNS tool (tested with dig, ssh,
and Net::DNS).
-
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.
This can be called as either a subroutine or a method. If called as a sub, you can pass any of the arguments accepted by the constructor as options. If called as a method, any additional options are ignored.
This returns the untainted hostname if the given $hostname is a valid
hostname.
Hostnames are not required to end in a valid TLD.
This can be called as either a subroutine or a method. If called as a sub, you can pass any of the arguments accepted by the constructor as options. If called as a method, any additional options are ignored.
This returns the untainted label if the given $label is a valid label.
A domain label is simply a single piece of a domain or hostname. For example, the "www.foo.com" hostname contains the labels "www", "foo", and "com".
[RFC 1034] [RFC 1035] [RFC 2181] [RFC 1123]
Thanks to Richard Sonnen <sonnen@richardsonnen.com> for writing the
Data::Validate module.
Thanks to Len Reed <lreed@levanta.com> for helping develop the options
mechanism for Data::Validate modules.
Bugs may be submitted at https://github.com/houseabsolute/Data-Validate-Domain/issues.
I am also usually active on IRC as 'autarch' on irc://irc.perl.org.
The source code repository for Data-Validate-Domain can be found at https://github.com/houseabsolute/Data-Validate-Domain.
- Neil Neely neil@neely.cx
- Dave Rolsky autarch@urth.org
- Anirvan Chatterjee anirvan@users.noreply.github.com
- David Steinbrunner dsteinbrunner@pobox.com
- Felipe Gasper felipe@felipegasper.com
- Gregory Oschwald goschwald@maxmind.com
This software is copyright (c) 2021 by Neil Neely.
This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.
The full text of the license can be found in the
LICENSE file included with this distribution.