NAME

Business::DK::Postalcode - Danish postal code validator and container

VERSION

This documentation describes version 0.08

SYNOPSIS

    # basic validation of string
    use Business::DK::Postalcode qw(validate);

    if (validate($postalcode)) {
        print "We have a valid Danish postalcode\n";
    } else {
        warn "Not a valid Danish postalcode\n";
    }


    # basic validation of string, using less intrusive subroutine
    use Business::DK::Postalcode qw(validate_postalcode);

    if (validate_postalcode($postalcode)) {
        print "We have a valid Danish postal code\n";
    } else {
        warn "Not a valid Danish postal code\n";
    }


    # using the untainted return value
    use Business::DK::Postalcode qw(validate_postalcode);

    if (my $untainted = validate_postalcode($postalcode)) {
        print "We have a valid Danish postal code: $untainted\n";
    } else {
        warn "Not a valid Danish postal code\n";
    }


    # extracting a regex for validation of Danish postal codes
    use Business::DK::Postalcode qw(create_regex);

    my $regex_ref = ${create_regex()};

    if ($postalcode =~ m/$regex/) {
        print "We have a valid Danish postal code\n";
    } else {
        warn "Not a valid Danish postal code\n";
    }


    # All postal codes for use outside this module
    use Business::DK::Postalcode qw(get_all_postalcodes);

    my @postalcodes = @{get_all_postalcodes()};


    # All postal codes and data for use outside this module
    use Business::DK::Postalcode qw(get_all_data);

    my $postalcodes = get_all_data();

    foreach (@{postalcodes}) {
        printf
            'postal code: %s city: %s street/desc: %s company: %s province: %d country: %d', split /\t/, $_, 6;
    }

FEATURES

  • Providing list of Danish postal codes and related area names

  • Look up methods for Danish postal codes for web applications and the like

DESCRIPTION

This distribution is not the original resource for the included data, but simply acts as a simple distribution for Perl use. The central source is monitored so this distribution can contain the newest data. The monitor script (postdanmark.pl) is included in the distribution.

The data are converted for inclusion in this module. You can use different extraction subroutines depending on your needs:

Data

Here follows a description of the included data, based on the description from the original source and the authors interpretation of the data, including details on the distribution of the data.

city name

A non-unique, case-sensitive representation of a city name in Danish.

street/description

This field is either a streetname or a description, is it only provided for a few special records.

company name

This field is only provided for a few special records.

province

This field is a bit special and it's use is expected to be related to distribution all entries inside Copenhagen are marked as 'False' in this column and 'True' for all entries outside Copenhagen - and this of course with exceptions. The data are included since they are a part of the original data.

country

Since the original source contains data on 3 different countries:

  • Denmark

  • Greenland

  • Faroe Islands

Only the data representing Denmark has been included in this distribtion, so this field is always containing a one.

For access to the data on Greenland or Faroe Islands please refer to: Business::GL::Postalcode and Business::FO::Postalcode respectfully.

Encoding

The data distributed are in Danish for descriptions and names and these are encoded in UTF-8.

EXAMPLES

A web application example is included in the examples directory following this distribution or available at https://metacpan.org/pod/Business::DK::Postalcode.

SUBROUTINES AND METHODS

validate

A simple validator for Danish postal codes.

Takes a string representing a possible Danish postal code and returns either 1 or 0 indicating either validity or invalidity.

    my $rv = validate(2665);

    if ($rv == 1) {
        print "We have a valid Danish postal code\n";
    } ($rv == 0) {
        print "Not a valid Danish postal code\n";
    }

validate_postalcode

A less intrusive subroutine for import. Acts as a wrapper of "validate".

    my $rv = validate_postalcode(2300);

    if ($rv) {
        print "We have a valid Danish postal code\n";
    } else {
        print "Not a valid Danish postal code\n";
    }

get_all_data

Returns a reference to a a list of strings, separated by tab characters. See "Data" for a description of the fields.

    use Business::DK::Postalcode qw(get_all_data);

    my $postalcodes = get_all_data();

    foreach (@{postalcodes}) {
        printf
            'postalcode: %s city: %s street/desc: %s company: %s province: %d country: %d', split /\t/, $_, 6;
    }

get_all_postalcodes

Takes no parameters.

Returns a reference to an array containing all valid Danish postal codes.

    use Business::DK::Postalcode qw(get_all_postalcodes);

    my $postalcodes = get_all_postalcodes;

    foreach my $postalcode (@{$postalcodes}) { ... }

get_all_cities

Takes no parameters.

Returns a reference to an array containing all Danish city names having a postal code.

    use Business::DK::Postalcode qw(get_all_cities);

    my $cities = get_all_cities;

    foreach my $city (@{$cities}) { ... }

Please note that this data source used in this distribution by no means is authorative when it comes to cities located in Denmark, it might have all cities listed, but unfortunately also other post distribution data.

get_city_from_postalcode

Takes a string representing a Danish postal code.

Returns a single string representing the related city name or an empty string indicating nothing was found.

    use Business::DK::Postalcode qw(get_city_from_postalcode);

    my $zipcode = '2300';

    my $city = get_city_from_postalcode($zipcode);

    if ($city) {
        print "We found a city for $zipcode\n";
    } else {
        warn "No city found for $zipcode";
    }

get_postalcode_from_city

Takes a string representing a Danish city name.

Returns a reference to an array containing zero or more postal codes related to that city name. Zero indicates nothing was found.

Please note that city names are not unique, hence the possibility of a list of postal codes.

    use Business::DK::Postalcode qw(get_postalcode_from_city);

    my $city = 'København K';

    my $postalcodes = get_postalcode_from_city($city);

    if (scalar @{$postalcodes} == 1) {
        print "$city is unique\n";
    } elsif (scalar @{$postalcodes} > 1) {
        warn "$city is NOT unique\n";
    } else {
        die "$city not found\n";
    }

create_regex

This method returns a generated regular expression for validation of a string representing a possible Danish postal code.

    use Business::DK::Postalcode qw(create_regex);

    my $regex_ref = ${create_regex()};

    if ($postalcode =~ m/$regex/) {
        print "We have a valid Danish postalcode\n";
    } else {
        print "Not a valid Danish postalcode\n";
    }

PRIVATE SUBROUTINES AND METHODS

_retrieve_cities

Takes a reference to an array based on the DATA section and return a reference to an array containing only city names.

_retrieve_postalcode

Takes a reference to an array based on the DATA section and return a reference to an array containing only postal codes.

_build_tree

Internal method to assist "create_regex" in generating the regular expression.

Takes a https://metacpan.org/pod/Tree::Simple object and a reference to an array of data elements.

DIAGNOSTICS

There are not special diagnostics apart from the ones related to the different subroutines.

CONFIGURATION AND ENVIRONMENT

This distribution requires no special configuration or environment.

DEPENDENCIES

TEST

Please note that the above list does not reflect requirements for:

  • Additional components in this distribution, see lib/. Additional components list own requirements

  • Test and build system, please see: Build.PL for details

  • Requirements for scripts in the bin/ directory

  • Requirements for examples in the examples/ directory

BUGS AND LIMITATIONS

There are no known bugs at this time.

The data source used in this distribution by no means is authorative when it comes to cities located in Denmark, it might have all cities listed, but unfortunately also other post distribution data.

BUG REPORTING

Please report issues via CPAN RT:

INCOMPATIBILITIES

There are no known incompatibilities at this time.

TEST AND QUALITY

Perl::Critic

This version of the code is complying with https://metacpan.org/pod/Perl::Critic a severity: 1

The following policies have been disabled.

Please see t/perlcriticrc for details.

TEST COVERAGE

Test coverage report is generated using https://metacpan.org/pod/Devel::Cover via https://metacpan.org/pod/Module::Build, for the version described in this documentation (See VERSION).

    ---------------------------- ------ ------ ------ ------ ------ ------ ------
    File                           stmt   bran   cond    sub    pod   time  total
    ---------------------------- ------ ------ ------ ------ ------ ------ ------
    ...Business/DK/Postalcode.pm  100.0  100.0    n/a  100.0  100.0   98.7  100.0
    ...Business/DK/Postalcode.pm  100.0  100.0    n/a  100.0  100.0    1.2  100.0
    Total                         100.0  100.0    n/a  100.0  100.0  100.0  100.0
    ---------------------------- ------ ------ ------ ------ ------ ------ ------

    $ ./Build testcover

SEE ALSO

RESOURCES

TODO

Please see the project TODO file, or the bugtracker (RT), website or issues resource at Github.

AUTHOR

Jonas B. Nielsen, (jonasbn) - <jonasbn@cpan.org>

MOTIVATION

Back in 2006 I was working on a project where I needed to do some presentation and validation of Danish postal codes. I looked at https://metacpan.org/pod/Regex::Common::Zip

The implementation at the time of writing looked as follows:

    Denmark     =>  "(?k:(?k:[1-9])(?k:[0-9])(?k:[0-9]{2}))",
    # Postal codes of the form: 'DDDD', with the first
    # digit representing the distribution region, the
    # second digit the distribution district. Postal
    # codes do not start with a zero. Postal codes
    # starting with '39' are in Greenland.

This pattern holds some issues:

  • Doing some fast math you can see that you will allow 9000 valid postal codes where the number should be about 1254

  • 0 is actually allowed for a set of postal codes used by the postal service in Denmark, in some situations these should perhaps be allowed as valid data

  • Greenland specified as starting with '39' is not a part of Denmark, but should be under Greenland and the ISO code 'GL', see also:

So I decided to write a regular expression, which would be better than the one above, but I did not want to maintain it I wanted to write a piece of software, which could generate the pattern for me based on a finite data set.

COPYRIGHT

Business-DK-Postalcode is (C) by Jonas B. Nielsen, (jonasbn) 2006-2014

LICENSE

Business-DK-Postalcode and related is released under the Artistic License 2.0