NAME DataFlow - A framework for dataflow processing VERSION version 1.111510 SYNOPSIS use DataFlow; my $flow = DataFlow->new( procs => [ DataFlow::Proc->new( p => sub { do this thing } ), sub { ... do something }, sub { ... do something else }, CSV => { direction => 'TO_CSV', text_csv_opts => { binary => 1 }, }, ] ); $flow->input( ); my $output = $flow->output(); my $output = $flow->output( ); DESCRIPTION A "DataFlow" object is able to accept data, feed it into an array of processors (DataFlow::Proc objects), and return the result(s) back to the caller. ATTRIBUTES name [Str] A descriptive name for the dataflow. (OPTIONAL) auto_process [Bool] If there is data available in the output queue, and one calls the "output()" method, this attribute will flag whether the dataflow should attempt to automatically process queued data. (DEFAULT: true) procs [ArrayRef[DataFlow::Proc]] The list of processors that make this DataFlow. Optionally, you may pass CodeRefs that will be automatically converted to DataFlow::Proc objects. (REQUIRED) The "procs" parameter will accept some variations in its value. Any "ArrayRef" passed will be parsed, and additionaly to plain "DataFlow::Proc" objects, it will accept: "DataFlow" objects (so one can nest flows), code references ("sub{}" blocks) and plain text strings. The text string form is treatedi, for a given "TEXT", in the following order: if it contains '::' then DataFlow will try to use a class named "TEXT"; it that doesn't work (or if it doesn't contain '::'), DataFlow will try to load a class named 'DataFlow::Proc::TEXT'; if that fails, it tries one last time to load a class named 'TEXT'. If that last try doesn't work, it dies. Additionally, one may pass any of these forms as a single argument to the constructor "new", plus a single "DataFlow", or "DataFlow:Proc" or string. METHODS has_queued_data Returns true if the dataflow contains any queued data within. clone Returns another instance of a "DataFlow" using the same array of processors. input Accepts input data for the data flow. It will gladly accept anything passed as parameters. However, it must be noticed that it will not be able to make a distinction between arrays and hashes. Both forms below will render the exact same results: $flow->input( qw/all the simple things/ ); $flow->input( all => 'the', simple => 'things' ); If you do want to handle arrays and hashes differently, we strongly suggest that you use references: $flow->input( [ qw/all the simple things/ ] ); $flow->input( { all => the, simple => 'things' } ); Processors with "process_into" enabled (true by default) will process the items inside an array reference, and the values (not the keys) inside a hash reference. process_input Processes items in the array of queues and place at least one item in the output (last) queue. One will typically call this to flush out some unwanted data and/or if "auto_process" has been disabled. output Fetches data from the data flow. If called in scalar context it will return one processed item from the flow. If called in list context it will return all the elements in the last queue. flush Flushes all the data through the dataflow, and returns the complete result set. process Immediately processes a bunch of data, without touching the object queues. It will process all the provided data and return the complete result set for it. HISTORY This is a framework for data flow processing. It started as a spinoff project from the OpenData-BR initiative. As of now (Mar, 2011) it is still a 'work in progress', and there is a lot of progress to make. It is highly recommended that you read the tests, and the documentation of DataFlow::Proc, to start with. An article has been recently written in Brazilian Portuguese about this framework, per the São Paulo Perl Mongers "Equinócio" (Equinox) virtual event. Although an English version of the article in in the plans, you can figure a good deal out of the original one at UPDATE: DataFlow is a fast-evolving project, and this article, as it was published there, refers to versions 0.91.x of the framework. There has been a big refactor since then and, although the concept remains the same, since version 0.950000 the programming interface has been changed violently. Any doubts, feel free to get in touch. AUTHOR Alexei Znamensky COPYRIGHT AND LICENSE This software is copyright (c) 2011 by Alexei Znamensky. This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself. SUPPORT Perldoc You can find documentation for this module with the perldoc command. perldoc DataFlow Websites The following websites have more information about this module, and may be of help to you. As always, in addition to those websites please use your favorite search engine to discover more resources. * Search CPAN The default CPAN search engine, useful to view POD in HTML format. * AnnoCPAN The AnnoCPAN is a website that allows community annonations of Perl module documentation. * CPAN Ratings The CPAN Ratings is a website that allows community ratings and reviews of Perl modules. * CPAN Forum The CPAN Forum is a web forum for discussing Perl modules. * CPANTS The CPANTS is a website that analyzes the Kwalitee ( code metrics ) of a distribution. * CPAN Testers The CPAN Testers is a network of smokers who run automated tests on uploaded CPAN distributions. * CPAN Testers Matrix The CPAN Testers Matrix is a website that provides a visual way to determine what Perls/platforms PASSed for a distribution. Internet Relay Chat You can get live help by using IRC ( Internet Relay Chat ). If you don't know what IRC is, please read this excellent guide: . Please be courteous and patient when talking to us, as we might be busy or sleeping! You can join those networks/channels and get help: * irc.perl.org You can connect to the server at 'irc.perl.org' and join this channel: #opendata-br to get help. BUGS AND LIMITATIONS No bugs have been reported. Please report any bugs or feature requests through the web interface at . AVAILABILITY The latest version of this module is available from the Comprehensive Perl Archive Network (CPAN). Visit to find a CPAN site near you, or see . The development version lives at and may be cloned from . Instead of sending patches, please fork this project using the standard git and github infrastructure. DISCLAIMER OF WARRANTY BECAUSE THIS SOFTWARE IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY FOR THE SOFTWARE, TO THE EXTENT PERMITTED BY APPLICABLE LAW. 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