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Data::Serializer::Cookbook.3pm

NAME

Cookbook - Examples of how to use Data::Serializer

DESCRIPTION

Data::Serializer::Cookbook is a collection of solutions for using Data::Serializer.

CONVENTIONS

Unless otherwise specified, all examples can be assumed to begin with:

   use Data::Serializer;
 
   my $serializer = Data::Serializer->new();
 
 

Some examples will show different arguments to the new method, where specified simply use that line instead of the simple form above.

Encrypting your data

You wish to encrypt your data structure, so that it can only be decoded by someone who shares the same key.

Solution

   $serializer->secret('mysecret');
 
   my $encrypted_hashref = $serializer->serializer($hash);
 
   ... (in other program) ...
 
   $serializer->secret('mysecret');
 
   my $clear_hash = $serializer->deserializer($encrypted_hash);
 
 

Note: You will have to have the Crypt::CBC module installed for this to work.

Compressing your data

You wish to compress your data structure to cut down on how much disk space it will take up.

Solution

   $serializer->compress(1);
 
   my $compressed_hashref = $serializer->serializer($hash);
 
   ... (in other program) ...
 
   my $clear_hash = $serializer->deserializer($compressed_hash);
 
 

Note: You will have to have the Compress::Zlib module installed for this to work. Your mileage will vary dramatically depending on what serializer you use. Some serializers are already fairly compact.

You want to read in data serialized outside of Data::Serializer

You need to write a program that can read in data serialized in a format other than Data::Serializer. For example you need to be able to be able to process data serialized by XML::Dumper.

Solution

   my $xml_serializer = Data::Serializer->(serializer => 'XML::Dumper', raw => 1);
 
   my $hash_ref = $serializer->deserialize($xml_data);
 
 

Note: the raw_deserialize method can be used as well, but the above approach is preferred.

You want to write serialized data in a form understood outside of Data::Serializer

You need to write a program that can write out data in a format other than Data::Serializer. Or said more generically you need to write out data in the format native to the underlying serializer. For our example we will be exporting data using XML::Dumper format.

Solution

   my $xml_serializer = Data::Serializer->(serializer => 'XML::Dumper', raw => 1);
 
   my $xml_data = $serializer->serialize($hash_ref);
 
 

Note: the raw_serialize method can be used as well, but the above approach is preferred.

You want to convert data between two different serializers native formats

You have data serialized by php that you want to convert to xml for use by other programs.

Solution

   my $xml_serializer = Data::Serializer->(serializer => 'XML::Dumper', raw => 1);
 
   my $php_serializer = Data::Serializer->(serializer => 'PHP::Serialization', raw => 1);
 
   my $hash_ref = $php_serializer->deserialize($php_data);
 
   my $xml_data = $xml_serializer->serialize($hash_ref);
 
 

Keeping data persistent between executions of a program.

You have a program that you run every 10 minutes, it uses SNMP to pull some counters from one of your routers. You want your program to keep the counters from the last run so that it can see how much traffic has passed over a link since it last ran.

Solution

   # path to store our serialized data
   # be paranoid, use full paths
   my $last_run_datafile = '/full/path/to/file/lastrun.data';
 
   #We keep our data as a hash reference
   my $last_data = $serializer->retrieve($last_run_datafile);
   
   #Pull in our new data through 'pull_data()';
   my $new_data = query_router($router);
 
   #run comparison code
   run_comparison($last_data,$new_data);
 
   $serializer->store($new_data);
 
 

AUTHOR

Neil Neely <neil@neely.cx>.

COPYRIGHT

Copyright (c) 2001-2008 Neil Neely. All rights reserved.

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

SEE ALSO

Data::Serializer(3)