http://qs321.pair.com?node_id=387941

2ge has asked for the wisdom of the Perl Monks concerning the following question:

Hi monks!

I know how to validate XML, but still error massages appears on STDOUT, anyone knows how to avoid them ? my code looks: 
use strict;
use XML::Checker::Parser;

my $xml_file = 'data.xml';
my $xp = new XML::Checker::Parser ( Handlers => { } );

eval {
  $xp->parsefile($xml_file);
  local $XML::Checker::FAIL = \&my_fail;
};

if ($@) {
  print "$xml_file failed validation!\n";
} else {
  print "$xml_file passed validation\n";
}

sub my_fail {
  my $code = shift;
  die XML::Checker::error_message ($code, @_) if $code < 300;
}

[download]
data.xml is: 
<?xml version="1.0" encoding="utf-8"?>
<series>
<article>
<url>http://builder.com.com/article.jhtml?id=..htm</url>
<title>Remedial XML for programmers: Basic syntax</title>
<summary>In this first installment in...</summary>
</article>
</series>

[download]
OUTPUT is: 

XML::Checker ERROR-101: undefined ELEMENT [series]
        Context: line 2, column 0, byte 40
XML::Checker ERROR-101: undefined ELEMENT [article]
        Context: line 3, column 6, byte 56
XML::Checker ERROR-101: undefined ELEMENT [url]
        Context: line 4, column 13, byte 80
XML::Checker ERROR-101: undefined ELEMENT [title]
        Context: line 5, column 13, byte 167
XML::Checker ERROR-101: undefined ELEMENT [summary]
        Context: line 6, column 13, byte 239
data.xml passed validation

[download]
I dont't want to see error messages.
thanks a lot!

Replies are listed 'Best First'.
Re: XML validating (no DTD)
by ikegami (Patriarch) on Sep 02, 2004 at 15:57 UTC

    Change

    $xp->parsefile($xml_file);
local $XML::Checker::FAIL = \&my_fail;

    [download]

    to

    local $XML::Checker::FAIL = \&my_fail;
$xp->parsefile($xml_file);

    [download]

    It does no good to set the error handler after the checking is done.

[reply]
[d/l]
[select]
Re: XML validating (no DTD)
by Plankton (Vicar) on Sep 02, 2004 at 15:48 UTC
[reply]
Re: XML validating (no DTD)
by iburrell (Chaplain) on Sep 02, 2004 at 16:47 UTC
    I don't see any DTD declared in the XML or the code. If you don't have a schema to validate against, you can't validate an XML document. Checking for well-formed is different, and something most parsers should report on. XML::Checker::Parser looks like it only validates against DTDs declared in the document.

    You can also validate against XML Schema or RELAX NG. I don't know of any pure Perl code for those, but calling external programs and libraries work well.

[reply]
      Hi

      I just found the solution on perlmonks, it is so easy: 
      use XML::Parser;

my $p = XML::Parser->new;
my $file = 'data.xml';

eval { $p->parsefile($file) };

if ($@) {
  print 'XML is not well formed';
} else {
  print 'XML is well formed';
}

      [download]


      Ofcoure, I can't validate XML, if I don't have DTD, I can check it if it is well formed, sorry for mistake.
[reply]
[d/l]

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