NAME
    URL::Normalize - Normalize/optimize URLs.

VERSION
    Version 0.13

SYNOPSIS
        use URL::Normalize;

        my $Normalizer = URL::Normalize->new(
            url => 'http://www.example.com/display?lang=en&article=fred',
        );

        # ...or

        my $Normalizer = URL::Normalize->new(
            url  => '/display?lang=en&article=fred',
            base => 'http://www.example.com',
        );

        # Get a normalized URL back

        $Normalizer->do_all(); # Perform all the normalizations available

        print $Normalizer->get_url();

DESCRIPTION
    This is NOT a perfect solution. If you normalize a URL using all the
    methods in this module, there is a high probability that the URL will
    "stop working". This is merely a helper module for those of you who
    wants to either normalize a URL using only a few of the safer methods,
    and/or for those of you who wants to generate a unique "ID" from any
    given URL.

    When writing a web crawler, for example, it's always very costly to
    check if a URL has been fetched/seen when you have millions or billions
    of URLs in a sort of database. This module can help you create a unique
    "ID", which you then can use as a key in a key/value-store; the key is
    the normalized URL, whereas all the URLs that converts to the normalized
    URL are part of the value (normally an array or hash);

        'http://www.example.com/' = {
            'http://www.example.com:80/'        => 1,
            'http://www.example.com/index.html' => 1,
            'http://www.example.com/?'          => 1,
        }

    Above, all the URLs inside the hash normalizes to the key if you run
    these methods:

    * `make_canonical()'
    * `remove_directory_index()'
    * `remove_empty_query()'

CONSTRUCTORS
  new( %opts )
    Constructs a new URL::Normalize object. Takes a hash as input argument;

        my $Normalizer = URL::Normalize->new(
            url  => '/foobar.html',            # required
            base => 'http://www.example.com/', # optional
        );

METHODS
  get_URI()
    Returns the `URI' object representing the current state of the URL.

  get_url()
    Returns the current URL.

  get_base()
    Returns the current base.

  make_canonical()
    Just a shortcut for URI::URL->new()->canonical()->as_string(), and
    involves the following steps (at least):

    * Converts the scheme and host to lower case.
    * Capitalizes letters in escape sequences.
    * Decodes percent-encoded octets of unreserved characters.
    * Removes the default port (port 80 for http).

    Example:

        my $Normalizer = URL::Normalize->new(
            url => 'http://www.example.com/%7Eusername/',
        );

        $Normalize->make_canonical();

        print $Normalize->get_url(); # http://www.example.com/~username/

  remove_dot_segments()
    The segments ".." and "." will be removed from the URL according to the
    algorithm described in RFC 3986.

    Example:

        my $Normalizer = URL::Normalize->new(
            url => 'http://www.example.com/../a/b/../c/./d.html',
        );

        $Normalize->remove_dot_segments();

        print $Normalize->get_url(); # http://www.example.com/a/c/d.html

  remove_directory_index()
    Removes well-known directory indexes, eg. "index.html", "default.asp"
    etc.

    Example:

        my $Normalizer = URL::Normalize->new(
            url => 'http://www.example.com/index.cgi?foo=/',
        );

        $Normalizer->remove_directory_index();

        print $Normalizer->get_url(); # http://www.example.com/?foo=/

    You are free to modify the global `$DIRECTORY_INDEX_REGEXPS' arrayref to
    your own fitting:

        $URL::Normalize::DIRECTORY_INDEX_REGEXPS = [ ... ];

        my $Normalizer = URL::Normalize->new(
            url => 'http://www.example.com/index.cgi?foo=/',
        );

        $Normalizer->remove_directory_index();

        print $Normalizer->get_url(); # whatever

  sort_query_parameters()
    Sorts the query parameters alphabetically.

    Uppercased parameters will be lower cased during sorting only, and if
    there are multiple values for a parameter, the key/value-pairs will be
    sorted as well.

    Example:

        my $Normalizer = URL::Normalize->new(
            url => 'http://www.example.com/?b=2&c=3&a=0&A=1',
        );

        $Normalizer->sort_query_parameters();

        print $Normalizer->get_url(); # http://www.example.com/?a=0&A=1&b=2&c=3

  remove_duplicate_query_parameters()
    Removes duplicate query parameters, ie. where the key/value combination
    is identical with another key/value combination.

    Example:

        my $Normalizer = URL::Normalize->new(
            url => 'http://www.example.com/?a=1&a=2&b=4&a=1&c=4',
        );

        $Normalizer->remove_duplicate_query_parameters();

        print $Normalizer->get_url(); # http://www.example.com/?a=1&a=2&b=3&c=4

  remove_empty_query_parameters()
    Removes empty query parameters, ie. where there are keys with no value.

    Example:

        my $Normalizer = URL::Normalize->new(
            url => 'http://www.example.com/?a=1&b=&c=3',
        );

        $Normalize->remove_empty_query_parameters();

        print $Normalizer->get_url(); # http://www.example.com/?a=1&c=3

  remove_empty_query()
    Removes empty query from the URL.

    Example:

        my $Normalizer = URL::Normalize->new(
            url => 'http://www.example.com/foo?',
        );

        $Normalizer->remove_empty_query();

        print $Normalize->get_url(); # http://www.example.com/foo

  remove_fragment()
    Removes fragments from the URL.

    Example:

        my $Normalizer = URL::Normalize->new(
            url => 'http://www.example.com/bar.html#section1',
        );

        $Normalizer->remove_fragment();

        print $Normalizer->get_url(); # http://www.example.com/bar.html

  remove_duplicate_slashes()
    Remove duplicate slashes from the URL.

    Example:

        my $Normalizer = URL::Normalize->new(
            url => 'http://www.example.com/foo//bar.html',
        );

        $Normalizer->remove_duplicate_slashes();

        print $Normalizer->get_url(); # http://www.example.com/foo/bar.html

  remove_hostname_prefix()
    Removes 'www' followed by a potential number before the actual hostname.

    Example:

        my $Normalizer = URL::Normalize->new(
            url => 'http://www.example.com/',
        );

        $Normalizer->remove_hostname_prefix();

        print $Normalizer->get_url(); # http://example.com/

  do_all()
    Performs all of the normalization methods mentioned above.

PERFORMANCE
    There's probably possible to improve the performance of this module
    considerably, but as premature optimization is evil, I'll wait until the
    functionality and API is stable.

    On my MacBook Pro (2.66GHz i7, 8GB RAM) running Perl 5.14.2, I'm able to
    run the do_all() method on more than 1,100 URLs per second. This is just
    a number, as the performance depends on the complexity of the URL.

SEE ALSO
    * URI
    * URI::URL
    * URI::QueryParam
    * RFC 3986: Uniform Resource Indentifier
    * Wikipedia: URL normalization

AUTHOR
    Tore Aursand, `<toreau at gmail.com>'

BUGS
    Please report any bugs or feature requests to the web interface at
    https://github.com/toreau/url-normalize/issues/new.

SUPPORT
    You can find documentation for this module with the perldoc command.

        perldoc URL::Normalize

    You can also look for information at:

    * github (report bugs here)
        https://github.com/toreau/url-normalize/issues

    * AnnoCPAN: Annotated CPAN documentation
        http://annocpan.org/dist/URL-Normalize

    * CPAN Ratings
        http://cpanratings.perl.org/d/URL-Normalize

    * Search CPAN
        http://search.cpan.org/dist/URL-Normalize/

LICENSE AND COPYRIGHT
    Copyright 2012 Tore Aursand.

    This program is free software; you can redistribute it and/or modify it
    under the terms of the the Artistic License (2.0). You may obtain a copy
    of the full license at:

    http://www.perlfoundation.org/artistic_license_2_0

    Any use, modification, and distribution of the Standard or Modified
    Versions is governed by this Artistic License. By using, modifying or
    distributing the Package, you accept this license. Do not use, modify,
    or distribute the Package, if you do not accept this license.

    If your Modified Version has been derived from a Modified Version made
    by someone other than you, you are nevertheless required to ensure that
    your Modified Version complies with the requirements of this license.

    This license does not grant you the right to use any trademark, service
    mark, tradename, or logo of the Copyright Holder.

    This license includes the non-exclusive, worldwide, free-of-charge
    patent license to make, have made, use, offer to sell, sell, import and
    otherwise transfer the Package with respect to any patent claims
    licensable by the Copyright Holder that are necessarily infringed by the
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