object::signature::file(3pm) [debian man page]

Object::Signature::File(3pm)				User Contributed Perl Documentation			      Object::Signature::File(3pm)

NAME

       Object::Signature::File - Extended signature API for storing objects in file

DESCRIPTION

       Whereas the basic Object::Signature class provides for only a raw cryptographic signature, Object::Signature::File extends the signature
       method to add specialised information for objects that want some control over how they are stored as files.

       For example, some objects may want the cached object to have a matching file extension (for example a gif image) so that web-accessible
       cache path could be used in a web page.

       The image would then be sent out to the browser with the correct mime type.

METHODS

   signature_ext
       The "signature_ext" method indicates the preferable file extension for the content of the object, if applicable.

       If the method returns a string, it indicates the object should be stored in a file with a specific extension.

       If the method returns a null string, it indicates that the file should be stored with no extension.

       If the method return "undef" (the default value), it indicates no preference for the extension the file.

   signature_name
       This signature_name method is the least-useful part of this extended API, and is rarely used. It is included mostly for completeness.

       If the method returns a string, it indicates the name part of a file name that the object should be stored in, if possible.

       If the method return a null string, it explicitly indicates there is no file name or a file name is not possible.

       If the method returns "undef" (the default value), it indicates no preference for the name of the file.

AUTHOR

       Adam Kennedy <adamk@cpan.org>

COPYRIGHT

       Copyright 2004 - 2007 Adam Kennedy.

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

       The full text of the license can be found in the LICENSE file included with this module.

perl v5.12.3							    2011-06-13					      Object::Signature::File(3pm)

Object::Signature(3pm)					User Contributed Perl Documentation				    Object::Signature(3pm)

NAME

       Object::Signature - Generate cryptographic signatures for objects

SYNOPSIS

	 # In your module
	 package My::Module
	 use base 'Object::Signature';

	 # In outside code
	 my $Object = My::Module->new;
	 print "Object Signature: " . $Object->signature;

DESCRIPTION

       Object::Signature is an abstract base class that you can inherit from in order to allow your objects to generate unique cryptographic
       signatures.

       The method used to generate the signature is based on Storable and Digest::MD5. The object is fed to "Storable::nfreeze" to get a string,
       which is then passed to Digest::MD5::md5_hex to get a unique 32 character hexidecimal signature.

METHODS

   signature
       The "signature" method is the only method added to your class, and will generate a unique 32 hexidecimal signature for any object it is
       called on.

SUPPORT

       All bugs should be filed via the bug tracker at

       http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Object-Signature <http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Object-Signature>

       For other issues, or commercial enhancement or support, contact the author.

TO DO

   Incremental Generation
       Currently has to generate the entire Storable string before digesting it. Would be nice if there was a way to incrementally Storablise and
       Digest in one pass so that it becomes much more memory efficient for large objects.

   Strengthen the Digest Algorithm
       Once the current (as of 2005) hashing controversy settles down, consider selecting a newer and more powerful hashing algorithm to replace
       MD5. Or offer alternatives depending on how important the security situation is, as MD5 is very fast (90 meg a second) and many more-secure
       ones are a lot slower (more than 10 times slower in some cases).

       On our side is the fact we use Storable. It should be much harder to create collisions when you don't control the string, only the
       structure before it goes through Storable.

AUTHOR

       Adam Kennedy <adamk@cpan.org>

SEE ALSO

       Object::Signature::File, <http://ali.as/>

COPYRIGHT

       Copyright 2004 - 2011 Adam Kennedy.

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

       The full text of the license can be found in the LICENSE file included with this module.

perl v5.12.3							    2011-03-24						    Object::Signature(3pm)