Message-SmartMerge use Message::SmartMerge; my $merge = Message::SmartMerge->new(); $merge->config({ merge_instance => 'instance', }); $merge->message({ instance => 'i1', x => 'y', this => 'whatever', }); #no merges, so pass through: #emit sends { instance => 'i1', x => 'y', this => 'whatever' } $merge->add_merge({ merge_id => 'm1', match => {x => 'y'}, transform => {this => 'that'}, }); #so we've already passed through a message instance i1, and this new #merge matches that, so the module will send a transformed message: { instance => 'i1', x => 'y', this => 'that', } #Now send another message through: $merge->message({ instance => 'i1', x => 'y', this => 'not that', something => 'else', }); #merge matches x => 'y', so transforms this => 'that': #emit sends: { instance => 'i1', x => 'y', this => 'that', something => 'else' } $merge->remove_merge('m1'); #even though we didn't send a message in, removing a merge will trigger #an emit to reflect that a change has occurred, specifically that the #previously activated transform is no longer in force. It sends the #last message received, without the transform #emit sends: { instance => 'i1', x => 'y', this => 'not that', something => 'else' } #Here's a way the message stream can clear a merge: $merge->add_merge({ merge_id => 'm2', match => { x => 'y', }, transform => { foo => 'bar', }, toggle_fields => ['something'], }); #Since m2 also matches x => 'y', we emit: { instance => 'i1', x => 'y', this => 'not that', something => 'else', foo => 'bar', } $merge->message({ instance => 'i1', x => 'y', foo => 'not bar', something => 'else', another => 'thing', }); #the value of the single defined toggle field ('something') did not #change from the first value we saw in it ('else'). So m2 stands: { instance => 'i1', x => 'y', something => 'else', foo => 'bar', another => 'thing', } #even though we passed 'not bar' in with foo, it was transformed to 'bar' #Now let's hit the toggle: $merge->message({ instance => 'i1', x => 'y', foo => 'not bar', something => 'other', another => 'thing', }); #this will 'permanently' remove the merge m2 for i1; the message passes #through untransformed: { instance => 'i1', x => 'y', foo => 'not bar', something => 'other', another => 'thing', } #Here's another way the message stream can clear a merge: $merge->add_merge({ merge_id => 'm3', match => { i => 'j', }, transform => { a => 'b', }, remove_match => { remove => 'match', }, }); #This causes nothing to emit, because there are no instances that match #i => 'j' $merge->message({ instance => 'i2', x => 'y', i => 'j', foo => 'not bar', a => 'not b', something => 'here', }); #this is fun because it matches both m2 and m3. it would have matched #m1 had we not removed it #i2 has never been seen before, and m2 is a toggle. The toggle #deallocates itself for an instance if the toggle field changes #from the previous to the current message. Since there was no #previous message for i2, the toggle merge deallocates itself for i2 #before it can take any action. { instance => 'i2', x => 'y', i => 'j', foo => 'not bar', something => 'here', a => 'b', #rather than 'not b' } #and now to deallocate m3: $merge->message({ instance => 'i2', x => 'y', i => 'j', a => 'not b', remove => 'match', }); #which emits: { instance => 'i2', x => 'y', i => 'j', a => 'not b', #no longer transformed remove => 'match', } INSTALLATION To install this module, run the following commands: perl Makefile.PL make make test make install SUPPORT AND DOCUMENTATION After installing, you can find documentation for this module with the perldoc command. perldoc Message::SmartMerge You can also look for information at: Report bugs and feature requests here https://github.com/dana/perl-Message-SmartMerge/issues AnnoCPAN, Annotated CPAN documentation http://annocpan.org/dist/Message-SmartMerge CPAN Ratings http://cpanratings.perl.org/d/Message-SmartMerge Search CPAN https://metacpan.org/module/Message::SmartMerge LICENSE AND COPYRIGHT Copyright (C) 2013 Dana M. Diederich This program is free software; you can redistribute it and/or modify it under the terms of the the Artistic License (2.0). You may obtain a copy of the full license at: L Any use, modification, and distribution of the Standard or Modified Versions is governed by this Artistic License. By using, modifying or distributing the Package, you accept this license. Do not use, modify, or distribute the Package, if you do not accept this license. If your Modified Version has been derived from a Modified Version made by someone other than you, you are nevertheless required to ensure that your Modified Version complies with the requirements of this license. This license does not grant you the right to use any trademark, service mark, tradename, or logo of the Copyright Holder. This license includes the non-exclusive, worldwide, free-of-charge patent license to make, have made, use, offer to sell, sell, import and otherwise transfer the Package with respect to any patent claims licensable by the Copyright Holder that are necessarily infringed by the Package. If you institute patent litigation (including a cross-claim or counterclaim) against any party alleging that the Package constitutes direct or contributory patent infringement, then this Artistic License to you shall terminate on the date that such litigation is filed. Disclaimer of Warranty: THE PACKAGE IS PROVIDED BY THE COPYRIGHT HOLDER AND CONTRIBUTORS "AS IS' AND WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES. THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT ARE DISCLAIMED TO THE EXTENT PERMITTED BY YOUR LOCAL LAW. UNLESS REQUIRED BY LAW, NO COPYRIGHT HOLDER OR CONTRIBUTOR WILL BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING IN ANY WAY OUT OF THE USE OF THE PACKAGE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.