RFC: DBIx::Counter - persistent counter class

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I've been a CPAN consumer for so long, I thought it's about time to start
I wrote a little module that does exactly the same as File::CounterFile, but
with a database as storage engine.
It came into this world after a thread on www.experts-exchange.com; so there's
at least one interested user for it.

Granted, it's nothing earth-shattering, but it's simple and generic enough to be
useful outside my usual work, and it presents me with a
manageable package to start my CPAN career.
Before I go all the way by applying for a PAUSE account and uploading it, I
would like to put it to public scrutiny first. I'd like to know
I'm doing things properly from the start.

Here's my list of questions:
- what about the module name? is it good?
- code review would be nice
- documentation: clear enough?
- tests: for a module this simple?
- exception handling: should I do this myself, or let DBI throw them?

The archive is here: http://www.rhesa.com/DBIx-Counter-0.01.tar.gz

Thanks for your attention!


Here's the pod:

     DBIx::Counter - Manipulate named counters stored in a database

         use DBIx::Counter;
         $c = new DBIx::Counter('my counter',
                                 dsn       => 'dbi:mysql:mydb',
                                 login     => 'username',
                                 password  => 'secret'
         print $c->value;

     This module creates and maintains named counters in a database. It has a
     simple interface, with methods to increment and decrement the counter by
     one, and a method for retrieving the value. It supports operator
     overloading for increment (++), decrement (--) and stringification ("").
     It should perform well in persistent environments, since it uses the
     connect_cached and prepare_cached methods of DBI. The biggest advantage
     over its main inspiration - File::CounterFile - is that it allows
     distributed, concurrent access to the counters and isn't tied to a
     single file system.

     Connection settings can be set in the constructor, or by using the
     package variables $DSN, $LOGIN and $PASSWORD and $TABLENAME. The table
     name is configurable, but the column names are currently hard-coded to
     counter_id and value. The following SQL statement can be used to create
     the table:

         CREATE TABLE counters (
             counter_id  varchar(64) primary key,
             value       int not null default 0

     This module attempts to mimick the File::CounterFile interface, except
     currently it only supports integer counters. The locking functions in
     File::CounterFile are present for compatibility only: they always return

     new Creates a new counter instance. First parameter is the required
         counter name. Second, optional, argument is an initial value for the
         counter on its very first use. It also accepts named parameters for
         the dbi connection string, dbi login and dbi password, and the table

             dsn         - overrides $DBIx::Counter::DSN
             login       - overrides $DBIx::Counter::LOGIN
             password    - overrides $DBIx::Counter::PASSWORD
             tablename   - overrides $DBIx::Counter::TABLENAME

             $c = new DBIx::Counter('my counter');
             $c = new DBIx::Counter('my counter',
                                     dsn       => 'dbi:mysql:mydb',
                                     login     => 'username',
                                     password  => 'secret'
             $c = new DBIx::Counter('my counter',
                                     dsn       => 'dbi:mysql:mydb',
                                     tablename => 'gauges'

     inc increases the counter by one.

             # or using overload:

     dec decreases the counter by one.

             # or using overload:

         returns the current value of the counter.

             print $c->value;
             # or using overload:
             print $c;



     Copyright (C) 2005 by Rhesa Rozendaal

     This library is free software; you can redistribute it and/or modify it
     under the same terms as Perl itself, either Perl version 5.8.2 or, at
     your option, any later version of Perl 5 you may have available.

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