NAME
XML::Tidy - tidy indenting of XML documents
VERSION
This documentation refers to version 1.20 of XML::Tidy, which was
released on Sun Jul 9 09:43:30:08 -0500 2017.
SYNOPSIS
#!/usr/bin/perl
use strict;use warnings;
use utf8;use XML::Tidy;
# create new XML::Tidy object by loading: MainFile.xml
my $tidy_obj = XML::Tidy->new('filename' => 'MainFile.xml');
# tidy up the indenting
$tidy_obj->tidy();
# write out changes back to MainFile.xml
$tidy_obj->write();
DESCRIPTION
This module creates XML document objects (with inheritance from
XML::XPath) to tidy mixed-content (i.e., non-data) text node indenting.
There are also some other handy member functions to compress and expand
your XML document object (into either a compact XML representation or a
binary one).
USAGE
new()
This is the standard Tidy object constructor. Except for the added
'binary' option, it can take the same parameters as an XML::XPath object
constructor to initialize the XML document object. These can be any one
of:
'filename' => 'SomeFile.xml'
'binary' => 'SomeBinaryFile.xtb'
'xml' => $variable_which_holds_a_bunch_of_XML_data
'ioref' => $file_InputOutput_reference
'context' => $existing_node_at_specified_context_to_become_new_obj
reload()
The reload() member function causes the latest data contained in a Tidy
object to be re-parsed (which re-indexes all nodes).
This can be necessary after modifications have been made to nodes which
impact the tree node hierarchy because XML::XPath's find() member
preserves state information which can get out-of-sync.
reload() is probably rarely useful by itself but it is needed by strip()
and prune() so it is exposed as a method in case it comes in handy for
other uses.
strip()
The strip() member function searches the Tidy object for all
mixed-content (i.e., non-data) text nodes and empties them out. This
will basically unformat any markup indenting.
strip() is used by compress() and tidy() but it is exposed because it is
also worthwhile by itself.
tidy()
The tidy() member function can take a single optional parameter as the
string that should be inserted for each indent level. Some examples:
# Tidy up indenting with default two (2) spaces per indent level
$tidy_obj->tidy();
# Tidy up indenting with four (4) spaces per indent level
$tidy_obj->tidy(' ');
# Tidy up indenting with one (1) tab per indent level
$tidy_obj->tidy('tab' );
# Tidy up indenting with two (2) tabs per indent level
$tidy_obj->tidy("\t\t");
The default behavior is to use two (2) spaces for each indent level. The
Tidy object gets all mixed-content (i.e., non-data) text nodes
reformatted to appropriate indent levels according to tree nesting
depth.
NOTE: tidy() disturbs some XML escapes in whatever ways XML::XPath does.
It has been brought to my attention that these modules also strip CDATA
tags from XML files / data they operate on. Even though CDATA tags don't
seem very common, I would very much like for them to work smoothly too.
Hopefully the vast majority of files will work fine and future support
for any of the more rare types can be added later.
Additionally, please take notice that every call to tidy() (as well as
reload, strip, and most other XML::Tidy functions) leak some memory due
to their usage of XPath's findnodes command. This issue was described
helpfully at <HTTPS://RT.CPAN.Org/Ticket/Display.html?id=120296>. Thanks
to Jozef!
compress()
The compress() member function calls strip() on the Tidy object then
creates an encoded comment which contains the names of elements and
attributes as they occurred in the original document. Their respective
element and attribute names are replaced with just the appropriate index
throughout the document.
compress() can accept a parameter describing which node types to attempt
to shrink down as abbreviations. This parameter should be a string of
just the first letters of each node type you wish to include as in the
following mapping:
e = elements
a = attribute keys
v = attribute values *EXPERIMENTAL*
t = text nodes *EXPERIMENTAL*
c = comment nodes *EXPERIMENTAL*
n = namespace nodes *not-yet-implemented*
Attribute values ('v') and text nodes ('t') both seem to work fine with
current tokenization. I've still labeled them EXPERIMENTAL because they
seem more likely to cause problems than valid element or attribute key
names. I have some bugs in the comment node compression which I haven't
been able to find yet so that one should be avoided for now. Since these
three node types ('vtc') all require tokenization, they are not included
in default compression ('ea'). An example call which includes values and
text would be:
$tidy_obj->compress('eavt');
The original document structure (i.e., node hierarchy) is preserved.
compress() significantly reduces the file size of most XML documents for
when size matters more than immediate human readability. expand()
performs the opposite conversion.
expand()
The expand() member function reads any XML::Tidy::compress comments from
the Tidy object and uses them to reconstruct the document that was
passed to compress().
bcompress('BinaryOutputFilename.xtb')
The bcompress() member function stores a binary representation of any
Tidy object. The format consists of:
0) a null-terminated version string
1) a byte specifying how many bytes later indices will be
2) the number of bytes from 1 above to designate the total string count
3) the number of null-terminated strings from 2 above
4) the number of bytes from 1 above to designate the total integer count
5) the number of 4-byte integers from 4 above
6) the number of bytes from 1 above to designate the total float count
7) the number of 8-byte (double-precision) floats from 6 above
8) node index sets until the end of the file
Normal node index sets consist of two values. The first is an index
(again the number of bytes long comes from 1) into the three lists as if
they were all linear. The second is a single-byte integer identifying
the node type (using standard DOM node type enumerations).
A few special cases exist in node index sets though. If the index is
null, it is interpreted as a close-element tag (so no accompanying type
value is read). On the other end, when the index is non-zero, the type
value is always read. In the event that the type corresponds to an
attribute or a processing instruction, the next index is read (without
another accompanying type value) in order to complete the data fields
required by those node types.
NOTE: Please bear in mind that the encoding of binary integers and
floats only works properly if the values are not surrounded by spaces or
other delimiters and each is contained in its own single node. This is
necessary to enable thorough reconstruction of whitespace from the
original document. I recommend storing every numerical value as an
isolated attribute value or text node without any surrounding
whitespace.
# Examples which encode all numbers as binary:
<friend name="goodguy" category="15">
<hitpoints>31.255</hitpoints>
<location>
<x>-15.65535</x>
<y>16383.7</y>
<z>-1023.63</z>
</location>
</friend>
# Examples which encode all numbers as strings:
<enemy name="badguy" category=" 666 ">
<hitpoints> 2.0 </hitpoints>
<location> 4.0 -2.0 4.0 </location>
</enemy>
The default file extension is .xtb (for XML::Tidy Binary).
bexpand('BinaryInputFilename.xtb')
The bexpand() member function reads a binary file which was previously
written from bcompress(). bexpand() is an XML::Tidy object constructor
like new() so it can be called like:
my $xtbo = XML::Tidy->bexpand('BinaryInputFilename.xtb');
prune()
The prune() member function takes an XPath location to remove (along
with all attributes and child nodes) from the Tidy object. For example,
to remove all comments:
$tidy_obj->prune('//comment()');
or to remove the third baz (XPath indexing is 1-based):
$tidy_obj->prune('/foo/bar/baz[3]');
Pruning your XML tree is a form of tidying too so it snuck in here. =)
write()
The write() member function can take an optional filename parameter to
write out any changes to the Tidy object. If no parameters are given,
write() overwrites the original XML document file (if a 'filename'
parameter was given to the constructor).
write() will croak() if no filename can be found to write to.
write() can also take a secondary parameter which specifies an XPath
location to be written out as the new root element instead of the Tidy
object's root. Only the first matching element is written.
toString()
The toString() member function is almost identical to write() except
that it takes no parameters and simply returns the equivalent XML string
as a scalar. It is a little weird because normally only XML::XPath::Node
objects have a toString() member but I figure it makes sense to extend
the same syntax to the parent object as well, since it is a useful
option.
createNode Wrappers
The following are just aliases to Node constructors. They'll work with
just the unique portion of the node type as the member function name.
e() or el() or elem() or createElement()
wrapper for XML::XPath::Node::Element->new()
a() or at() or attr() or createAttribute()
wrapper for XML::XPath::Node::Attribute->new()
c() or cm() or cmnt() or createComment()
wrapper for XML::XPath::Node::Comment->new()
t() or tx() or text() or createTextNode()
wrapper for XML::XPath::Node::Text->new()
p() or pi() or proc() or createProcessingInstruction()
wrapper for XML::XPath::Node::PI->new()
n() or ns() or nspc() or createNamespace()
wrapper for XML::XPath::Node::Namespace->new()
EXPORTED CONSTANTS
Since they are sometimes needed to compare against, XML::Tidy also
exports the same node constants as XML::XPath::Node (which correspond to
DOM values). These include:
UNKNOWN_NODE
ELEMENT_NODE
ATTRIBUTE_NODE
TEXT_NODE
CDATA_SECTION_NODE
ENTITY_REFERENCE_NODE
ENTITY_NODE
PROCESSING_INSTRUCTION_NODE
COMMENT_NODE
DOCUMENT_NODE
DOCUMENT_TYPE_NODE
DOCUMENT_FRAGMENT_NODE
NOTATION_NODE
ELEMENT_DECL_NODE
ATT_DEF_NODE
XML_DECL_NODE
ATTLIST_DECL_NODE
NAMESPACE_NODE
XML::Tidy also exports:
STANDARD_XML_DECL
which returns a reasonable default XML declaration string (assuming
typical "utf-8" encoding).
TODO
- fix reload() from messing up Unicode escaped &XYZ; components like
Copyright © and Registered ® (probably needs pre and post
processing)
- write many better UTF-8 tests
- support namespaces
- handle CDATA
CHANGES
Revision history for Perl extension XML::Tidy:
- 1.20 H79M9hU8 Sun Jul 9 09:43:30:08 -0500 2017
* removed broken Build.PL to resolve
<HTTPS://RT.CPAN.Org/Ticket/Display.html?id=122406>. (Thank you,
Slaven.)
- 1.18 H78M5qm1 Sat Jul 8 05:52:48:01 -0500 2017
* fixed new() to check file or xml to detect standalone in
declaration, from <HTTPS://RT.CPAN.Org/Ticket/Display.html?id=122389>
(Thanks Alex!)
* traced tidy() memory leak from
<HTTPS://RT.CPAN.Org/Ticket/Display.html?id=120296> (Thanks Jozef!)
which seems to come from every XPath->findnodes() call
* aligned synopsis comments
* updated write() to use output encoding UTF-8 since that's what
almost all XML should rely on (with thanks to RJBS for teaching me
much from his great talk at <HTTPS://YouTube.Com/watch?v=TmTeXcEixEg>)
* collapsed trailing curly braces on code blocks
* added croak for any failed file open attempt
- 1.16 G6LM4EST Tue Jun 21 04:14:28:29 -0500 2016
* stopped using my old fragile package generation and manually updated
all distribution files (though Dist::Zilla should let me generate much
again)
* updated license to GPLv3+
* fixed 00pod.t and 01podc.t to eval the Test modules from issue and
patch: <HTTPS://RT.CPAN.Org/Public/Bug/Display.html?id=85592> (Thanks
again MichielB.)
* replaced all old '&&' with 'and' in POD
- 1.14 G6JMERCY Sun Jun 19 14:27:12:34 -0500 2016
* separated old PT from VERSION to fix non-numeric issue:
<HTTPS://RT.CPAN.Org/Public/Bug/Display.html?id=56073> (Thanks to
Slaven.)
* removed Unicode from POD but added encoding utf8 anyway to pass
tests and resolve issues:
<HTTPS://RT.CPAN.Org/Public/Bug/Display.html?id=92434> and
<HTTPS://RT.CPAN.Org/Public/Bug/Display.html?id=85592> (Thanks to
Sudhanshu and MichielB.)
- 1.12.B55J2qn Thu May 5 19:02:52:49 2011
* made "1.0" float binarize as float again, rather than just "1" int
* cleaned up POD and fixed EXPORTED CONSTANTS heads blocking together
- 1.10.B52FpLx Mon May 2 15:51:21:59 2011
* added tests for undefined non-standard XML declaration to suppress
warnings
- 1.8.B2AMvdl Thu Feb 10 22:57:39:47 2011
* aligned .t code
* added test for newline before -r to try to resolve:
<HTTPS://RT.CPAN.Org/Ticket/Display.html?id=65471> (Thanks, Leandro.)
* fixed off-by-one error when new gets a readable (non-newline)
filename (that's not "filename" without a pre-'filename' param) to
resolve: <HTTPS://RT.CPAN.Org/Ticket/Display.html?id=65151> (Thanks,
Simone.)
- 1.6.A7RJKwl Tue Jul 27 19:20:58:47 2010
* added head2 POD for EXPORTED CONSTANTS to try to pass t/00podc.t
- 1.4.A7QCvHw Mon Jul 26 12:57:17:58 2010
* hacked a little test for non-UTF-8 decl str to resolve FrankGoss'
need for ISO-8859-1 decl encoding to persist through tidying
* md sure META.yml is being generated correctly for the CPAN
* updated license to GPLv3
- 1.2.75BACCB Fri May 11 10:12:12:11 2007
* made "1.0" float binarize as just "1" int
* made ints signed and bounds checked
* added new('binary' => 'BinFilename.xtb') option
- 1.2.54HJnFa Sun Apr 17 19:49:15:36 2005
* fixed tidy() processing instruction stripping problem
* added support for binary ints and floats in bcompress()
* tightened up binary format and added pod
- 1.2.54HDR1G Sun Apr 17 13:27:01:16 2005
* added bcompress() and bexpand()
* added compress() and expand()
* added toString()
- 1.2.4CKBHxt Mon Dec 20 11:17:59:55 2004
* added exporting of XML::XPath::Node (DOM) constants
* added node object creation wrappers (like LibXML)
- 1.2.4CCJW4G Sun Dec 12 19:32:04:16 2004
* added optional 'xpath_loc' => to prune()
- 1.0.4CAJna1 Fri Dec 10 19:49:36:01 2004
* added optional 'filename' => to write()
- 1.0.4CAAf5B Fri Dec 10 10:41:05:11 2004
* removed 2nd param from tidy() so that 1st param is just indent
string
* fixed pod errors
- 1.0.4C9JpoP Thu Dec 9 19:51:50:25 2004
* added xplc option to write()
* added prune()
- 1.0.4C8K1Ah Wed Dec 8 20:01:10:43 2004
* inherited from XPath so that those methods can be called directly
* original version (separating Tidy.pm from Merge.pm)
INSTALL
From the command shell, please run:
`perl -MCPAN -e "install XML::Tidy"`
or uncompress the package and run the standard:
`perl Makefile.PL; make; make test; make install`
FILES
XML::Tidy requires:
Carp to allow errors to croak() from calling sub
XML::XPath to use XPath statements to query and update XML
XML::XPath::XMLParser to parse XML documents into XPath objects
Math::BaseCnv to handle base-64 indexing for compress() and expand()
BUGS
Please report any bugs or feature requests to bug-XML-Tidy at
RT.CPAN.Org, or through the web interface at
<HTTPS://RT.CPAN.Org/NoAuth/ReportBug.html?Queue=XML-Tidy>. I will be
notified, and then you can be updated of progress on your bug as I
address fixes.
SUPPORT
You can find documentation for this module (after it is installed) with
the perldoc command.
`perldoc XML::Tidy`
You can also look for information at:
RT: CPAN's Request Tracker
HTTPS://RT.CPAN.Org/NoAuth/Bugs.html?Dist=XML-Tidy
AnnoCPAN: Annotated CPAN documentation
HTTP://AnnoCPAN.Org/dist/XML-Tidy
CPAN Ratings
HTTPS://CPANRatings.Perl.Org/d/XML-Tidy
Search CPAN
HTTP://Search.CPAN.Org/dist/XML-Tidy
LICENSE
Most source code should be Free! Code I have lawful authority over is
and shall be! Copyright: (c) 2004-2017, Pip Stuart. Copyleft : This
software is licensed under the GNU General Public License (version 3 or
later). Please consult <HTTPS://GNU.Org/licenses/gpl-3.0.txt> for
important information about your freedom. This is Free Software: you are
free to change and redistribute it. There is NO WARRANTY, to the extent
permitted by law. See <HTTPS://FSF.Org> for further information.
AUTHOR
Pip Stuart <Pip@CPAN.Org>