Class::DBI::Pageset - A flexible pager utility for Class::DBI using Data::Pageset

  package CD;
  use base qw(Class::DBI);
  use Class::DBI::Pageset;        # just use it
  __PACKAGE__->set_db(...);

  # then, in client code!
  package main;
  use CD;
  my $pager = CD->pager( {
            entries_per_page => 20,
            current_page     => 1,
            pages_per_set    => 10,
        } );
  my @disks = $pager->retrieve_all;

Class::DBI::Pageset is a plugin for Class::DBI that integrates Data::Pageset into Class::DBI with minimal fuss. This enables you to search via Class::DBI and grouping results into pages and page sets.

This module is very similar to Tatsuhiko Miyagawa's very nice Class::DBI::Pager module, but uses Data::Pageset (or any module that inherits from Data::Pageset, such as Data::Pageset::Render) to create the pager. Data::Pageset provides a more flexible pager, which is better suited to searches that return many pages. This is not necessarily very efficient (see NOTE below for more).

  # Controller: (MVC's C)
  my $query    = CGI->new;
  my $template = Template->new;

  my $pager    = Film->pager({ 
    entries_per_page => 20,
    current_page     => $query->param('page') || 1,
    pages_per_set    => 5, 
  });
  my $movies   = $pager->retrieve_all;
  $template->process($input, {
      movies => $movies,
      pager  => $pager,
  });

  # View: (MVC's V)
  Matched [% pager.total_entries %] items.

  [% WHILE (movie = movies.next) %]
  Title: [% movie.title | html %]
  [% END %]

  ### navigation like:   ... 5 [6] 7 8 9 ...
  [% IF pager.previous_set %] 
    <a href="display?page=[% pager.previous_set %]">...</a>
  [% END %]
  [% FOREACH num = [ pager.pages_in_set ] %]
  [% IF num == pager.current_page %] [[% num %]]
  [% ELSE %]<a href="display?page=[% num %]">[% num %]</a>[% END %]
  [% END %]
  [% IF pager.next_set %]
    <a href="display?page=[% pager.next_set %]">...</a>
  [% END %]

To use one of the modules that inherit from Data::Pageset (such as Data::Pageset::Render) just include the module name as part of the use statement.

    use Class::DBI::Pageset qw(Data::Pageset::Render);
    ## Then in your code you can use
    $pager->html( '<a href="index?page=%s">%a</a>' );

pager()

    my $pager = Film->pager({ 
        entries_per_page => 20,
        current_page     => $query->param('page') || 1,
        pages_per_set    => 5, 
        mode             => 'slide',
    });

This is the constructor for the pager. See Data::Pageset for more on the parameters. The $pager object can then be used as a normal Class::DBI object for searching.

total_entries()

entries_per_page()

current_page()

entries_on_this_page()

first_page()

last_page()

first()

last()

previous_page()

next_page()

pages_in_navigatio()

pages_per_set()

previous_set()

next_set()

pages_in_set()

See Data::Pageset.

This modules internally retrieves itertors, then creates Data::Page object for paging utility. Using SQL clauses LIMIT and/or OFFSET with DBIx::Pager might be more memory efficient. As this module is geared to searches that return many pages of results, it maybe more prone to inefficiencies than Class::DBI::Pager.

I had originally wanted to patch Class::DBI::Pager to use different pagers, ie, Data::Page, Data::Pageset, or Data::Pageset::Render, but the constructors for Data::Page and Data::Pageset are incompatible and jamming them together didn't seem like a good fix.

Class::DBI, Data::Pageset

Or for alternatives: Class::DBI::Pager, DBIx::Class, DBIx::Class::ResultSet::Data::Pageset

Please report any bugs or suggestions at http://rt.cpan.org/NoAuth/Bugs.html?Dist=Class-DBI-Pageset

Mark Grimes <mgrimes@cpan.org>

Most of this code was shamelessly taken from the very nice Class::DBI::Pager by Tatsuhiko Miyagawa <miyagawa@bulknews.net>.

Copyright (C) 2008 by mgrimes

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.