NAME

VERSION

SYNOPSIS

    use XML::SAX::Machines qw( Pipeline );   ## Most common way
    use XML::Fitler::Foo;

    my $m = Pipeline(
        XML::Filter::Foo->new,  ## Create it manually
        "XML::Filter::Bar",     ## Or let Pipeline load & create it
        "XML::Filter::Baz",
        {
            ## Normal options
            Handler => $h,
        }
    );

    ## To choose the default parser automatically if XML::Filter::Foo
    ## does not implement a parse_file method, just pretend the Pipeline
    ## is a parser:
    $m->parse_file( "blah" );

    ## To feed the pipeline from an upstream processor, treat it like
    ## any other SAX filter:
    my $p = Some::SAX::Generator->new( Handler => $m );

    ## To read a file or the output from a subprocess:
    my $m = Pipeline( "<infile.txt" );
    my $m = Pipeline( "spew_xml |" );

    ## To send output to a file handle, file, or process:
    my $m = Pipeline( ...,  \*STDOUT );
    my $m = Pipeline( ..., ">outfile.txt" );
    my $m = Pipeline( ..., "| xmllint --format -" );

DESCRIPTION

   +-----------------------------------------------------------+
   |                 An XML:SAX::Pipeline                      |
   |    Intake                                                 |
   |   +---------+    +---------+         +---------+  Exhaust |
 --+-->| Stage_0 |--->| Stage_1 |-->...-->| Stage_N |----------+----->
   |   +---------+    +---------+         +---------+          |
   +-----------------------------------------------------------+

As with all SAX machines, a pipeline can also create an ad hoc parser (using XML::SAX::ParserFactory) if you ask it to parse something and the first SAX processer in the pipeline can't handle a parse request:

   +-------------------------------------------------------+
   |                 An XML:SAX::Pipeline                  |
   |                 Intake                                |
   | +--------+   +---------+         +---------+  Exhaust |
   | | Parser |-->| Stage_0 |-->...-->| Stage_N |----------+----->
   | +--------+   +---------+         +---------+          |
   +-------------------------------------------------------+

or if you specify an input file like so:

   my $m = Pipeline(qw(
       <input_file.xml
       XML::Filter::Bar
       XML::Filter::Baz
   ));

Pipelines (and machines) can also create ad hoc XML::SAX::Writer instances when you specify an output file handle (as shown in the SYNOPSIS) or an output file:

   my $m = Pipeline(qw(
       XML::Filter::Bar
       XML::Filter::Baz
       >output_file.xml
   ));

And, thanks to Perl's magic open (see perlopentut), you can read and write from processes:

   my $m = Pipeline(
       "gen_xml.pl |",
       "XML::Filter::Bar",
       "XML::Filter::Baz",
       "| consume_xml.pl",
   );

This can be used with an XML::SAX::Tap to place a handy debugging tap in a pipeline (or other machine):

   my $m = Pipeline(
       "<input_file.xml"
       "XML::Filter::Bar",
       Tap( "| xmllint --format -" ),
       "XML::Filter::Baz",
       ">output_file.xml",
   );

NAME

METHODS

new

    my $pipeline = XML::SAX::Pipeline->new( @processors, \%options );
    

Creates a pipeline and links all of the given processors together. Longhand for Pipeline().

AUTHOR

    Barrie Slaymaker <barries@slaysys.com>

COPYRIGHT

    Copyright 2002, Barrie Slaymaker, All Rights Reserved.

You may use this module under the terms of the Artistic, GNU Public, or BSD licenses, your choice.

AUTHORS

• Barry Slaymaker
• Chris Prather <chris@prather.org>

COPYRIGHT AND LICENSE

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.