Factor SQL-standard deferred FK checks into a component

[dbsrgits/DBIx-Class.git] / lib / DBIx / Class / Storage / DBI / Pg.pm

diff --git a/lib/DBIx/Class/Storage/DBI/Pg.pm b/lib/DBIx/Class/Storage/DBI/Pg.pm
index 0dc7ea8..ee134c9 100644 (file)
--- a/lib/DBIx/Class/Storage/DBI/Pg.pm
+++ b/lib/DBIx/Class/Storage/DBI/Pg.pm
@@ -3,13 +3,8 @@ package DBIx::Class::Storage::DBI::Pg;
 use strict;
 use warnings;
 
-use base qw/
-    DBIx::Class::Storage::DBI::MultiColumnIn
-/;
-use mro 'c3';
+use base qw/DBIx::Class::Storage::DBI::SetConstraintsDeferred/;
 
-use Scope::Guard ();
-use Context::Preserve 'preserve_context';
 use DBIx::Class::Carp;
 use Try::Tiny;
 use namespace::clean;
@@ -17,6 +12,7 @@ use namespace::clean;
 __PACKAGE__->sql_limit_dialect ('LimitOffset');
 __PACKAGE__->sql_quote_char ('"');
 __PACKAGE__->datetime_parser_type ('DateTime::Format::Pg');
+__PACKAGE__->_use_multicolumn_in (1);
 
 sub _determine_supports_insert_returning {
   return shift->_server_info->{normalized_dbms_version} >= 8.002
@@ -25,20 +21,6 @@ sub _determine_supports_insert_returning {
   ;
 }
 
-sub with_deferred_fk_checks {
-  my ($self, $sub) = @_;
-
-  my $txn_scope_guard = $self->txn_scope_guard;
-
-  $self->_do_query('SET CONSTRAINTS ALL DEFERRED');
-
-  my $sg = Scope::Guard->new(sub {
-    $self->_do_query('SET CONSTRAINTS ALL IMMEDIATE');
-  });
-
-  return preserve_context { $sub->() } after => sub { $txn_scope_guard->commit };
-}
-
 # only used when INSERT ... RETURNING is disabled
 sub last_insert_id {
   my ($self,$source,@cols) = @_;
@@ -50,7 +32,7 @@ sub last_insert_id {
   for my $col (@cols) {
     my $seq = ( $col_info->{$col}{sequence} ||= $self->dbh_do('_dbh_get_autoinc_seq', $source, $col) )
       or $self->throw_exception( sprintf(
-        'could not determine sequence for column %s.%s, please consider adding a schema-qualified sequence to its column info',
+        "Could not determine sequence for column '%s.%s', please consider adding a schema-qualified sequence to its column info",
           $source->name,
           $col,
       ));
@@ -97,7 +79,7 @@ sub _dbh_get_autoinc_seq {
     $seq_expr = '' unless defined $seq_expr;
     $schema = "$schema." if defined $schema && length $schema;
     $self->throw_exception( sprintf (
-      'no sequence found for %s%s.%s, check the RDBMS table definition or explicitly set the '.
+      "No sequence found for '%s%s.%s', check the RDBMS table definition or explicitly set the ".
       "'sequence' for this column in %s",
         $schema ? "$schema." : '',
         $table,
@@ -106,7 +88,7 @@ sub _dbh_get_autoinc_seq {
     ));
   }
 
-  return $1;
+  return $1;  # exception thrown unless match is made above
 }
 
 # custom method for fetching column default, since column_info has a
@@ -164,33 +146,34 @@ sub sqlt_type {
   return 'PostgreSQL';
 }
 
-my $type_cache;
 sub bind_attribute_by_data_type {
   my ($self,$data_type) = @_;
 
-  # Ask for a DBD::Pg with array support
-  # pg uses (used?) version::qv()
-  require DBD::Pg;
-
-  if ($self->_server_info->{normalized_dbms_version} >= 9.0) {
-    if (not try { DBD::Pg->VERSION('2.17.2') }) {
-      carp_once( __PACKAGE__.': BYTEA columns are known to not work on Pg >='
-        . " 9.0 with DBD::Pg < 2.17.2\n" );
+  if ($self->_is_binary_lob_type($data_type)) {
+    # this is a hot-ish codepath, use an escape flag to minimize
+    # amount of function/method calls
+    # additionally version.pm is cock, and memleaks on multiple
+    # ->VERSION calls
+    # the flag is stored in the DBD namespace, so that Class::Unload
+    # will work (unlikely, but still)
+    unless ($DBD::Pg::__DBIC_DBD_VERSION_CHECK_DONE__) {
+      if ($self->_server_info->{normalized_dbms_version} >= 9.0) {
+        try { DBD::Pg->VERSION('2.17.2'); 1 } or carp (
+          __PACKAGE__.': BYTEA columns are known to not work on Pg >= 9.0 with DBD::Pg < 2.17.2'
+        );
+      }
+      elsif (not try { DBD::Pg->VERSION('2.9.2'); 1 } ) { carp (
+        __PACKAGE__.': DBD::Pg 2.9.2 or greater is strongly recommended for BYTEA column support'
+      )}
+
+      $DBD::Pg::__DBIC_DBD_VERSION_CHECK_DONE__ = 1;
     }
-  }
-  elsif (not try { DBD::Pg->VERSION('2.9.2') }) {
-    carp_once( __PACKAGE__.': DBD::Pg 2.9.2 or greater is strongly recommended'
-      . "for BYTEA column support.\n" );
-  }
 
-  # cache the result of _is_binary_lob_type
-  if (!exists $type_cache->{$data_type}) {
-    $type_cache->{$data_type} = $self->_is_binary_lob_type($data_type)
-      ? +{ pg_type => DBD::Pg::PG_BYTEA() }
-      : undef
+    return { pg_type => DBD::Pg::PG_BYTEA() };
+  }
+  else {
+    return undef;
   }
-
-  $type_cache->{$data_type};
 }
 
 sub _exec_svp_begin {
@@ -267,12 +250,13 @@ option to connect(), for example:
                     },
                   );
 
-=head1 AUTHORS
-
-See L<DBIx::Class/CONTRIBUTORS>
+=head1 FURTHER QUESTIONS?
 
-=head1 LICENSE
+Check the list of L<additional DBIC resources|DBIx::Class/GETTING HELP/SUPPORT>.
 
-You may distribute this code under the same terms as Perl itself.
+=head1 COPYRIGHT AND LICENSE
 
-=cut
+This module is free software L<copyright|DBIx::Class/COPYRIGHT AND LICENSE>
+by the L<DBIx::Class (DBIC) authors|DBIx::Class/AUTHORS>. You can
+redistribute it and/or modify it under the same terms as the
+L<DBIx::Class library|DBIx::Class/COPYRIGHT AND LICENSE>.