X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FDBIx%2FClass%2FStorage%2FDBI%2FReplicated%2FBalancer.pm;h=798c0ef556b9e617162a7102b3c07499ccf17e85;hb=41916570b3a93b05746e23b73c9a9b5005bc0d2e;hp=241d66602888d80340a4d5938fdc7e9c963b118d;hpb=64cdad22d9b4022de379ae43174c15ce8dc81b59;p=dbsrgits%2FDBIx-Class.git

diff --git a/lib/DBIx/Class/Storage/DBI/Replicated/Balancer.pm b/lib/DBIx/Class/Storage/DBI/Replicated/Balancer.pm
index 241d666..798c0ef 100644
--- a/lib/DBIx/Class/Storage/DBI/Replicated/Balancer.pm
+++ b/lib/DBIx/Class/Storage/DBI/Replicated/Balancer.pm
@@ -2,10 +2,13 @@ package DBIx::Class::Storage::DBI::Replicated::Balancer;
 
 use Moose::Role;
 requires 'next_storage';
+use MooseX::Types::Moose qw/Int/;
+
+use namespace::clean -except => 'meta';
 
 =head1 NAME
 
-DBIx::Class::Storage::DBI::Replicated::Balancer; A Software Load Balancer 
+DBIx::Class::Storage::DBI::Replicated::Balancer - A Software Load Balancer 
 
 =head1 SYNOPSIS
 
@@ -31,7 +34,7 @@ validating every query.
 
 has 'auto_validate_every' => (
   is=>'rw',
-  isa=>'Int',
+  isa=>Int,
   predicate=>'has_auto_validate_every',
 );
 
@@ -126,35 +129,57 @@ or just just forgot to create them :)
 around 'next_storage' => sub {
   my ($next_storage, $self, @args) = @_;
   my $now = time;
-    
+
   ## Do we need to validate the replicants?
   if(
      $self->has_auto_validate_every && 
      ($self->auto_validate_every + $self->pool->last_validated) <= $now
-  ) {
+  ) {   
       $self->pool->validate_replicants;
   }
-    
+
   ## Get a replicant, or the master if none
-  my $next = $self->$next_storage(@args);
-  return $next ? $next:$self->master; 
+  if(my $next = $self->$next_storage(@args)) {
+    return $next;
+  } else {
+    $self->master->debugobj->print("No Replicants validate, falling back to master reads. ");
+    return $self->master;
+  }
 };
 
-=head2 before: select
+=head2 increment_storage
 
-Advice on the select attribute.  Each time we use a replicant
-we need to change it via the storage pool algorithm.  That way we are spreading
-the load evenly (hopefully) across existing capacity.
+Rolls the Storage to whatever is next in the queue, as defined by the Balancer.
 
 =cut
 
-before 'select' => sub {
+sub increment_storage {
   my $self = shift @_;
   my $next_replicant = $self->next_storage;
   $self->current_replicant($next_replicant);
+}
+
+=head2 around: select
+
+Advice on the select attribute.  Each time we use a replicant
+we need to change it via the storage pool algorithm.  That way we are spreading
+the load evenly (hopefully) across existing capacity.
+
+=cut
+
+around 'select' => sub {
+  my ($select, $self, @args) = @_;
+  
+  if (my $forced_pool = $args[-1]->{force_pool}) {
+    delete $args[-1]->{force_pool};
+    return $self->_get_forced_pool($forced_pool)->select(@args); 
+  } else {
+    $self->increment_storage;
+    return $self->$select(@args);
+  }
 };
 
-=head2 before: select_single
+=head2 around: select_single
 
 Advice on the select_single attribute.  Each time we use a replicant
 we need to change it via the storage pool algorithm.  That way we are spreading
@@ -162,10 +187,16 @@ the load evenly (hopefully) across existing capacity.
 
 =cut
 
-before 'select_single' => sub {
-  my $self = shift @_;
-  my $next_replicant = $self->next_storage;
-  $self->current_replicant($next_replicant);
+around 'select_single' => sub {
+  my ($select_single, $self, @args) = @_;
+  
+  if (my $forced_pool = $args[-1]->{force_pool}) {
+    delete $args[-1]->{force_pool};
+    return $self->_get_forced_pool($forced_pool)->select_single(@args); 
+  } else {
+    $self->increment_storage;
+    return $self->$select_single(@args);
+  }
 };
 
 =head2 before: columns_info_for
@@ -178,10 +209,28 @@ the load evenly (hopefully) across existing capacity.
 
 before 'columns_info_for' => sub {
   my $self = shift @_;
-  my $next_replicant = $self->next_storage;
-  $self->current_replicant($next_replicant);
+  $self->increment_storage;
 };
 
+=head2 _get_forced_pool ($name)
+
+Given an identifier, find the most correct storage object to handle the query.
+
+=cut
+
+sub _get_forced_pool {
+  my ($self, $forced_pool) = @_;
+  if(blessed $forced_pool) {
+    return $forced_pool;
+  } elsif($forced_pool eq 'master') {
+    return $self->master;
+  } elsif(my $replicant = $self->pool->replicants($forced_pool)) {
+    return $replicant;
+  } else {
+    $self->master->throw_exception("$forced_pool is not a named replicant.");
+  }   
+}
+
 =head1 AUTHOR
 
 John Napiorkowski <john.napiorkowski@takkle.com>