###################################################################### PHP::HTTPBuildQuery 0.05 ###################################################################### 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