From: Andy Grundman <andy@hybridized.org>
Date: Fri, 26 Aug 2005 19:27:02 +0000 (+0000)
Subject: Added pager support, same syntax as Sweet.  Also fixed a few issues with ResultSet... 
X-Git-Tag: v0.03001~25
X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=commitdiff_plain;h=59f8e58434e28bd6005d9dfcca75a0efbb4f49e1;hp=0675cd04337cafdc5a8ce19e707e3b2ce2508087;p=dbsrgits%2FDBIx-Class.git

Added pager support, same syntax as Sweet.  Also fixed a few issues with ResultSet::count.  Table::count still does 2 SQL queries, we need to figure out how to fix that
---

diff --git a/Build.PL b/Build.PL
index 0853b8f..fd130ca 100644
--- a/Build.PL
+++ b/Build.PL
@@ -6,6 +6,7 @@ my %arguments = (
     license            => 'perl',
     module_name        => 'DBIx::Class',
     requires           => {
+        'Data::Page'                => 0,
         'DBI'                       => 0,
         'UNIVERSAL::require'        => 0,
         'NEXT'                      => 0,
diff --git a/lib/DBIx/Class/Core.pm b/lib/DBIx/Class/Core.pm
index 5dc4096..b1d95fa 100644
--- a/lib/DBIx/Class/Core.pm
+++ b/lib/DBIx/Class/Core.pm
@@ -9,6 +9,7 @@ use base qw/DBIx::Class/;
 __PACKAGE__->load_components(qw/
   InflateColumn
   Relationship
+  Pager
   PK
   Row
   Table
diff --git a/lib/DBIx/Class/Pager.pm b/lib/DBIx/Class/Pager.pm
new file mode 100644
index 0000000..1d715da
--- /dev/null
+++ b/lib/DBIx/Class/Pager.pm
@@ -0,0 +1,65 @@
+package DBIx::Class::Pager;
+
+use strict;
+use warnings;
+
+use NEXT;
+use Data::Page;
+
+=head1 NAME 
+
+DBIx::Class::Pager -  Pagination of resultsets
+
+=head1 SYNOPSIS
+
+=head1 DESCRIPTION
+
+This class lets you page through a resultset.
+
+=head1 METHODS
+
+=over 4
+
+=item page
+
+=item pager
+
+=cut
+
+*pager = \&page;
+
+sub page {
+  my $self = shift;
+  my ($criteria, $attr) = @_;
+  
+  my $rows    = $attr->{rows} || 10;
+  my $current = $attr->{page} || 1;
+  
+  # count must not use LIMIT, so strip out rows/offset
+  delete $attr->{$_} for qw/rows offset/;
+  
+  my $total = $self->count( $criteria, $attr );
+  my $page = Data::Page->new( $total, $rows, $current );
+  
+  $attr->{rows}   = $page->entries_per_page;
+  $attr->{offset} = $page->skipped;
+
+  my $iterator = $self->search( $criteria, $attr );
+
+  return ( $page, $iterator );
+}
+
+1;
+
+=back
+
+=head1 AUTHORS
+
+Andy Grundman <andy@hybridized.org>
+
+=head1 LICENSE
+
+You may distribute this code under the same terms as Perl itself.
+
+=cut
+
diff --git a/lib/DBIx/Class/ResultSet.pm b/lib/DBIx/Class/ResultSet.pm
index 644ff76..936bfdb 100644
--- a/lib/DBIx/Class/ResultSet.pm
+++ b/lib/DBIx/Class/ResultSet.pm
@@ -42,15 +42,19 @@ sub next {
 
 sub count {
   my ($self) = @_;
-  return $self->{attrs}{rows} if $self->{attrs}{rows};
-    # This is a hack, and will break on the last page of a paged set.
-    # Once we have limit support in Storage, kill it.
-
   my $db_class = $self->{class};
+
+  # offset breaks COUNT(*), so remove it
+  my $attrs = { %{ $self->{attrs} } };
+  delete $attrs->{offset};
+      
   my @cols = 'COUNT(*)';
   my ($c) = $db_class->storage->select_single($db_class->_table_name, \@cols,
-                                            $self->{cond}, $self->{attrs});
-  return $c; # ($cursor->next)[0];
+                                            $self->{cond}, $attrs);
+  return 0 unless $c;
+  return ( $attrs->{rows} && $attrs->{rows} < $c ) 
+    ? $attrs->{rows} 
+    : $c;
 }
 
 sub all {
diff --git a/t/07pager.t b/t/07pager.t
new file mode 100644
index 0000000..38a290a
--- /dev/null
+++ b/t/07pager.t
@@ -0,0 +1,72 @@
+use Test::More;
+
+plan tests => 8;
+
+use lib qw(t/lib);
+
+use_ok('DBICTest');
+
+# first page
+my ( $pager, $it ) = DBICTest::CD->page(
+    {},
+    { order_by => 'title',
+      rows => 3,
+      page => 1 }
+);
+      
+is( $pager->entries_on_this_page, 3, "entries_on_this_page ok" );
+
+is( $pager->next_page, 2, "next_page ok" );
+
+is( $it->next->title, "Caterwaulin' Blues", "iterator->next ok" );
+
+$it->next;
+$it->next;
+
+is( $it->next, undef, "next past end of page ok" );
+
+# second page
+( $pager, $it ) = DBICTest::CD->page( 
+    {},
+    { order_by => 'title',
+      rows => 3,
+      page => 2 }
+);
+
+is( $pager->entries_on_this_page, 2, "entries on second page ok" );
+
+is( $it->next->title, "Generic Manufactured Singles", "second page first title ok" );
+
+# XXX: Should we support disable_sql_paging?
+#( $pager, $it ) = DBICTest::CD->page(
+#    {},
+#    { rows => 2,
+#      page => 2,
+#      disable_sql_paging => 1 } );
+#
+#cmp_ok( $pager->total_entries, '==', 5, "disable_sql_paging total_entries ok" );
+#
+#cmp_ok( $pager->previous_page, '==', 1, "disable_sql_paging previous_page ok" );
+#
+#is( $it->next->title, "Caterwaulin' Blues", "disable_sql_paging iterator->next ok" );
+#
+#$it->next;
+#
+#is( $it->next, undef, "disable_sql_paging next past end of page ok" );
+
+# based on a failing criteria submitted by waswas
+# requires SQL::Abstract >= 1.20
+( $pager, $it ) = DBICTest::CD->page(
+    { title => [
+        -and => 
+            {
+                -like => '%bees'
+            },
+            {
+                -not_like => 'Forkful%'
+            }
+        ]
+    },
+    { rows => 5 }
+);
+is( $it->count, 1, "complex abstract count ok" );