Message::Passing::Role::Filter - Simple abstraction for filtering messages

       See Message::Passing.

perl v5.32.1                                       2021-11-09                Message::Passing::Role::Filter(3pm)

       Both a producer and a consumer of messages, able to filter out messages based upon their contents, or
       permute the structure of messages.

consume
       Consumers a message, calling the filter method provided by the user with the message.

       In the case where the filter returns a message, outputs the message to the next step in the chain.

       Message::Passing::Role::Filter - Simple abstraction for filtering messages

output_to
       From Message::Passing::Role::Input.

filter
       Called to filter the message. Returns the mangled message.

       Note if you return undef then the message is not propagated further up the chain, which may be used for
       filtering out unwanted messages.

       Message::Passing
       Message::Passing::Manual::Concepts

       This  module exists due to the wonderful people at Suretec Systems Ltd.  <http://www.suretecsystems.com/>
       who sponsored its development for its VoIP division called SureVoIP <http://www.surevoip.co.uk/> for  use
       with the SureVoIP API - <http://www.surevoip.co.uk/support/wiki/api_documentation>

           package My::Filter;
           use Moo;
           use namespace::clean -except => 'meta';

           with 'Message::Passing::Role::Filter';

           sub filter {
               my ($self, $message) = @_;
               # Do something with $message
               return $message; # Or return undef to halt message!
           }

           1;