######################################################################
    PHP::HTTPBuildQuery 0.09
######################################################################

NAME
    PHP::HTTPBuildQuery - Data structures become form-encoded query strings

SYNOPSIS
        use PHP::HTTPBuildQuery qw(http_build_query);

        my $query = http_build_query( 
            { foo => { 
                  bar => "baz", 
                      quick => { "quack" => "schmack" },
                  },
            },
        );

        # Query: "foo%5Bbar%5D=baz&foo%5Bquick%5D%5Bquack%5D=schmack"

        # URL decoded: "foo[bar]=baz", "foo[quick][quack]=schmack"

DESCRIPTION
    PHP::HTTPBuildQuery implements PHP's "http_build_query" function in
    Perl. It is used to form-encode Perl data structures in URLs, so that
    PHP can read them on the receiving end.

    New with version 0.04 comes "http_build_query_utf8" which has an
    identical syntax but deals with utf8 data instead. See the GOTCHAS
    section below for details.

    "http_build_query" accepts one mandatory and two optional parameters:

         http_build_query( $data, $prefix, $separator );

    where

    *   $data is a reference to the data structure (hash or array)

    *   $prefix is an array name for array elements at the top level. An
        array at the top level, as in

            http_build_query( [ 'foo', 'bar', 'baz' ]);

        would create a query string like:

            "0=foo&1=bar&2=baz"

        which PHP can't make sense of at the receiving end, as variables
        names can't start with a number. Adding a prefix, like in

            http_build_query( [ 'foo', 'bar', 'baz' ], "var");

        creates

            "var_0=foo&var_1=bar&var_2=baz"

        which then makes sense in PHP land.

    *   $seperator is an optional argument separator (defaults to '&'), used
        to separate the fields in the encoded string.

EXAMPLES
  Array
        $query = http_build_query( ['foo', 'bar'] );

        # Query: "name_0=foo&name_1=bar"

  Hash with Array
        $query = http_build_query( { foo => [ 'bar', 'baz' ] } );

        # Query: "foo[0]=bar&foo[1]=baz" (not escaped for readability)

GOTCHAS
    UTF8 Characters
        The "uri_escape()" function used in "http_build_query" won't encode
        utf8 characters. If your data is utf8 encoded, use
        "http_build_query_utf8" instead.

    Hash Element Order
        Perl hashes have no defined order, so if you encode something like
        "{ foo =" "bar", baz => "quack" }>, don't be surprised if you get
        the entries in a different order:

            # Query: "baz=quack&foo=bar"

    Frankenstein Arrays
        PHP's Frankenstein arrays handle numeric indexing and hash-like
        lookups transparently. For example, you could have a data structure
        like

              # PHP
            $a = array(
               'foo'  => 'bar',
               'baz',
            );
              # PHP

        and you could access both its numeric and associative elements:

             # PHP
           print $a[0];
             # prints: 'baz'

             # PHP
           print $a[foo];
             # prints: 'bar'

        PHP's "http_build_query" function would transform the Frankenstein
        array above to

            "foo=bar&0=baz"

        or, better, with a prefix of 'name', to

            "foo=bar&name_0=baz"

        In Perl, on the other hand, there's hashes for associative lookups
        and arrays for numerically indexed containers, so you can't mix and
        match, and there's no way to define a data structure to print out
        the query string above.

    Special Characters
        "http_build_query" creates a PHP-specific encoding format which
        can't handle ']' or '[' characters in its keys (they're ok in hash
        values, though). This module won't check against this case, it will
        just generate form strings that won't be decodable afterwards. Make
        sure to filter your data before passing it to "http_build_query()".

THANKS
    Thanks to the following Yahoos who provided advice, ideas and code: Sara
    Golemon, Rasmus Lerdorf, Evan Miller.

COPYRIGHT & LICENSE
    COPYRIGHT & LICENSE

    Copyright (c) 2008-2012 Yahoo! Inc. All rights reserved. The copyrights
    to the contents of this file are licensed under the Perl Artistic
    License (ver. 15 Aug 1997)

AUTHOR
    2008, Mike Schilli <cpan@perlmeister.com>