use strict;
use warnings;
+use base qw/DBIx::Class/;
+
use DBIx::Class::ResultSet;
use DBIx::Class::ResultSourceHandle;
use DBIx::Class::Exception;
-use Carp::Clan qw/^DBIx::Class/;
+use DBIx::Class::Carp;
+use DBIx::Class::GlobalDestruction;
use Try::Tiny;
use List::Util 'first';
-use Scalar::Util qw/weaken isweak/;
-use Storable qw/nfreeze thaw/;
+use Scalar::Util qw/blessed weaken isweak/;
use namespace::clean;
-use base qw/DBIx::Class/;
+__PACKAGE__->mk_group_accessors(simple => qw/
+ source_name name source_info
+ _ordered_columns _columns _primaries _unique_constraints
+ _relationships resultset_attributes
+ column_info_from_storage
+/);
-__PACKAGE__->mk_group_accessors('simple' => qw/_ordered_columns
- _columns _primaries _unique_constraints name resultset_attributes
- from _relationships column_info_from_storage source_info
- source_name sqlt_deploy_callback/);
+__PACKAGE__->mk_group_accessors(component_class => qw/
+ resultset_class
+ result_class
+/);
-__PACKAGE__->mk_group_accessors('component_class' => qw/resultset_class
- result_class/);
+__PACKAGE__->mk_classdata( sqlt_deploy_callback => 'default_sqlt_deploy_hook' );
=head1 NAME
# Create a table based result source, in a result class.
- package MyDB::Schema::Result::Artist;
+ package MyApp::Schema::Result::Artist;
use base qw/DBIx::Class::Core/;
__PACKAGE__->table('artist');
__PACKAGE__->add_columns(qw/ artistid name /);
__PACKAGE__->set_primary_key('artistid');
- __PACKAGE__->has_many(cds => 'MyDB::Schema::Result::CD');
+ __PACKAGE__->has_many(cds => 'MyApp::Schema::Result::CD');
1;
# Create a query (view) based result source, in a result class
- package MyDB::Schema::Result::Year2000CDs;
+ package MyApp::Schema::Result::Year2000CDs;
use base qw/DBIx::Class::Core/;
__PACKAGE__->load_components('InflateColumn::DateTime');
$new->{_relationships} = { %{$new->{_relationships}||{}} };
$new->{name} ||= "!!NAME NOT SET!!";
$new->{_columns_info_loaded} ||= 0;
- $new->{sqlt_deploy_callback} ||= "default_sqlt_deploy_hook";
return $new;
}
will attempt to retrieve the name of the sequence from the database
automatically.
+=item retrieve_on_insert
+
+ { retrieve_on_insert => 1 }
+
+For every column where this is set to true, DBIC will retrieve the RDBMS-side
+value upon a new row insertion (normally only the autoincrement PK is
+retrieved on insert). C<INSERT ... RETURNING> is used automatically if
+supported by the underlying storage, otherwise an extra SELECT statement is
+executed to retrieve the missing data.
+
=item auto_nextval
+ { auto_nextval => 1 }
+
Set this to a true value for a column whose value is retrieved automatically
from a sequence or function (if supported by your Storage driver.) For a
sequence, if you do not use a trigger to get the nextval, you have to set the
my $columns_info = $source->columns_info;
Like L</column_info> but returns information for the requested columns. If
-the optional column-list arrayref is ommitted it returns info on all columns
+the optional column-list arrayref is omitted it returns info on all columns
currently defined on the ResultSource via L</add_columns>.
=cut
my ($self,$seq) = @_;
my @pks = $self->primary_columns
- or next;
+ or return;
$_->{sequence} = $seq
for values %{ $self->columns_info (\@pks) };
=over
-=item Arguments: $callback
+=item Arguments: $callback_name | \&callback_code
+
+=item Return value: $callback_name | \&callback_code
=back
__PACKAGE__->sqlt_deploy_callback('mycallbackmethod');
+ or
+
+ __PACKAGE__->sqlt_deploy_callback(sub {
+ my ($source_instance, $sqlt_table) = @_;
+ ...
+ } );
+
An accessor to set a callback to be called during deployment of
the schema via L<DBIx::Class::Schema/create_ddl_dir> or
L<DBIx::Class::Schema/deploy>.
The callback can be set as either a code reference or the name of a
method in the current result class.
-If not set, the L</default_sqlt_deploy_hook> is called.
+Defaults to L</default_sqlt_deploy_hook>.
Your callback will be passed the $source object representing the
ResultSource instance being deployed, and the
=head2 default_sqlt_deploy_hook
-=over
-
-=item Arguments: $source, $sqlt_table
-
-=item Return value: undefined
-
-=back
-
-This is the sensible default for L</sqlt_deploy_callback>.
-
-If a method named C<sqlt_deploy_hook> exists in your Result class, it
-will be called and passed the current C<$source> and the
-C<$sqlt_table> being deployed.
+This is the default deploy hook implementation which checks if your
+current Result class has a C<sqlt_deploy_hook> method, and if present
+invokes it B<on the Result class directly>. This is to preserve the
+semantics of C<sqlt_deploy_hook> which was originally designed to expect
+the Result class name and the
+L<$sqlt_table instance|SQL::Translator::Schema::Table> of the table being
+deployed.
=cut
);
}
+=head2 name
+
+=over 4
+
+=item Arguments: None
+
+=item Result value: $name
+
+=back
+
+Returns the name of the result source, which will typically be the table
+name. This may be a scalar reference if the result source has a non-standard
+name.
+
=head2 source_name
=over 4
retrieval from this source. In the case of a database, the required FROM
clause contents.
+=cut
+
+sub from { die 'Virtual method!' }
+
=head2 schema
=over 4
sub reverse_relationship_info {
my ($self, $rel) = @_;
- my $rel_info = $self->relationship_info($rel);
+
+ my $rel_info = $self->relationship_info($rel)
+ or $self->throw_exception("No such relationship '$rel'");
+
my $ret = {};
return $ret unless ((ref $rel_info->{cond}) eq 'HASH');
- my @cond = keys(%{$rel_info->{cond}});
- my @refkeys = map {/^\w+\.(\w+)$/} @cond;
- my @keys = map {$rel_info->{cond}->{$_} =~ /^\w+\.(\w+)$/} @cond;
+ my $stripped_cond = $self->__strip_relcond ($rel_info->{cond});
- # Get the related result source for this relationship
- my $othertable = $self->related_source($rel);
+ my $rsrc_schema_moniker = $self->source_name
+ if try { $self->schema };
+
+ # this may be a partial schema or something else equally esoteric
+ my $other_rsrc = try { $self->related_source($rel) }
+ or return $ret;
# Get all the relationships for that source that related to this source
# whose foreign column set are our self columns on $rel and whose self
- # columns are our foreign columns on $rel.
- my @otherrels = $othertable->relationships();
- my $otherrelationship;
- foreach my $otherrel (@otherrels) {
- # this may be a partial schema with the related source not being
- # available at all
- my $back = try { $othertable->related_source($otherrel) } or next;
-
- # did we get back to ourselves?
- next unless $back->source_name eq $self->source_name;
-
- my $otherrel_info = $othertable->relationship_info($otherrel);
- my @othertestconds;
-
- if (ref $otherrel_info->{cond} eq 'HASH') {
- @othertestconds = ($otherrel_info->{cond});
- }
- elsif (ref $otherrel_info->{cond} eq 'ARRAY') {
- @othertestconds = @{$otherrel_info->{cond}};
+ # columns are our foreign columns on $rel
+ foreach my $other_rel ($other_rsrc->relationships) {
+
+ # only consider stuff that points back to us
+ # "us" here is tricky - if we are in a schema registration, we want
+ # to use the source_names, otherwise we will use the actual classes
+
+ # the schema may be partial
+ my $roundtrip_rsrc = try { $other_rsrc->related_source($other_rel) }
+ or next;
+
+ if ($rsrc_schema_moniker and try { $roundtrip_rsrc->schema } ) {
+ next unless $rsrc_schema_moniker eq $roundtrip_rsrc->source_name;
}
else {
- next;
+ next unless $self->result_class eq $roundtrip_rsrc->result_class;
}
- foreach my $othercond (@othertestconds) {
- my @other_cond = keys(%$othercond);
- my @other_refkeys = map {/^\w+\.(\w+)$/} @other_cond;
- my @other_keys = map {$othercond->{$_} =~ /^\w+\.(\w+)$/} @other_cond;
- next if (!$self->_compare_relationship_keys(\@refkeys, \@other_keys) ||
- !$self->_compare_relationship_keys(\@other_refkeys, \@keys));
- $ret->{$otherrel} = $otherrel_info;
- }
+ my $other_rel_info = $other_rsrc->relationship_info($other_rel);
+
+ # this can happen when we have a self-referential class
+ next if $other_rel_info eq $rel_info;
+
+ next unless ref $other_rel_info->{cond} eq 'HASH';
+ my $other_stripped_cond = $self->__strip_relcond($other_rel_info->{cond});
+
+ $ret->{$other_rel} = $other_rel_info if (
+ $self->_compare_relationship_keys (
+ [ keys %$stripped_cond ], [ values %$other_stripped_cond ]
+ )
+ and
+ $self->_compare_relationship_keys (
+ [ values %$stripped_cond ], [ keys %$other_stripped_cond ]
+ )
+ );
}
+
return $ret;
}
+# all this does is removes the foreign/self prefix from a condition
+sub __strip_relcond {
+ +{
+ map
+ { map { /^ (?:foreign|self) \. (\w+) $/x } ($_, $_[1]{$_}) }
+ keys %{$_[1]}
+ }
+}
+
sub compare_relationship_keys {
carp 'compare_relationship_keys is a private method, stop calling it';
my $self = shift;
# Returns true if both sets of keynames are the same, false otherwise.
sub _compare_relationship_keys {
- my ($self, $keys1, $keys2) = @_;
-
- # Make sure every keys1 is in keys2
- my $found;
- foreach my $key (@$keys1) {
- $found = 0;
- foreach my $prim (@$keys2) {
- if ($prim eq $key) {
- $found = 1;
- last;
- }
- }
- last unless $found;
- }
+# my ($self, $keys1, $keys2) = @_;
+ return
+ join ("\x00", sort @{$_[1]})
+ eq
+ join ("\x00", sort @{$_[2]})
+ ;
+}
- # Make sure every key2 is in key1
- if ($found) {
- foreach my $prim (@$keys2) {
- $found = 0;
- foreach my $key (@$keys1) {
- if ($prim eq $key) {
- $found = 1;
- last;
- }
- }
- last unless $found;
+# optionally takes either an arrayref of column names, or a hashref of already
+# retrieved colinfos
+# returns an arrayref of column names of the shortest unique constraint
+# (matching some of the input if any), giving preference to the PK
+sub _identifying_column_set {
+ my ($self, $cols) = @_;
+
+ my %unique = $self->unique_constraints;
+ my $colinfos = ref $cols eq 'HASH' ? $cols : $self->columns_info($cols||());
+
+ # always prefer the PK first, and then shortest constraints first
+ USET:
+ for my $set (delete $unique{primary}, sort { @$a <=> @$b } (values %unique) ) {
+ next unless $set && @$set;
+
+ for (@$set) {
+ next USET unless ($colinfos->{$_} && !$colinfos->{$_}{is_nullable} );
}
+
+ # copy so we can mangle it at will
+ return [ @$set ];
}
- return $found;
+ return undef;
}
# Returns the {from} structure used to express JOIN conditions
$jpath = [@$jpath]; # copy
- if (not defined $join) {
+ if (not defined $join or not length $join) {
return ();
}
elsif (ref $join eq 'ARRAY') {
-alias => $as,
-relation_chain_depth => $seen->{-relation_chain_depth} || 0,
},
- $self->_resolve_condition($rel_info->{cond}, $as, $alias, $join) ];
+ scalar $self->_resolve_condition($rel_info->{cond}, $as, $alias, $join)
+ ];
}
}
$self->_resolve_condition (@_);
}
-# Resolves the passed condition to a concrete query fragment. If given an alias,
-# returns a join condition; if given an object, inverts that object to produce
-# a related conditional from that object.
-our $UNRESOLVABLE_CONDITION = \'1 = 0';
+our $UNRESOLVABLE_CONDITION = \ '1 = 0';
+# Resolves the passed condition to a concrete query fragment and a flag
+# indicating whether this is a cross-table condition. Also an optional
+# list of non-triviail values (notmally conditions) returned as a part
+# of a joinfree condition hash
sub _resolve_condition {
- my ($self, $cond, $as, $for, $rel) = @_;
+ my ($self, $cond, $as, $for, $relname) = @_;
+
+ my $obj_rel = !!blessed $for;
+
if (ref $cond eq 'CODE') {
+ my $relalias = $obj_rel ? 'me' : $as;
+
+ my ($crosstable_cond, $joinfree_cond) = $cond->({
+ self_alias => $obj_rel ? $as : $for,
+ foreign_alias => $relalias,
+ self_resultsource => $self,
+ foreign_relname => $relname || ($obj_rel ? $as : $for),
+ self_rowobj => $obj_rel ? $for : undef
+ });
- # heuristic for the actual relname
- if (! defined $rel) {
- if (!ref $as) {
- $rel = $as;
+ my $cond_cols;
+ if ($joinfree_cond) {
+
+ # FIXME sanity check until things stabilize, remove at some point
+ $self->throw_exception (
+ "A join-free condition returned for relationship '$relname' without a row-object to chain from"
+ ) unless $obj_rel;
+
+ # FIXME another sanity check
+ if (
+ ref $joinfree_cond ne 'HASH'
+ or
+ first { $_ !~ /^\Q$relalias.\E.+/ } keys %$joinfree_cond
+ ) {
+ $self->throw_exception (
+ "The join-free condition returned for relationship '$relname' must be a hash "
+ .'reference with all keys being valid columns on the related result source'
+ );
}
- elsif (!ref $for) {
- $rel = $for;
+
+ # normalize
+ for (values %$joinfree_cond) {
+ $_ = $_->{'='} if (
+ ref $_ eq 'HASH'
+ and
+ keys %$_ == 1
+ and
+ exists $_->{'='}
+ );
}
- }
- if (! defined $rel) {
- $self->throw_exception ('Unable to determine relationship name for condition resolution');
- }
+ # see which parts of the joinfree cond are conditionals
+ my $relcol_list = { map { $_ => 1 } $self->related_source($relname)->columns };
- return $cond->({
- self_alias => ref $for ? $as : $for,
- foreign_alias => ref $for ? $self->related_source($rel)->resultset->current_source_alias : $as,
- self_resultsource => $self,
- foreign_relname => $rel,
- self_rowobj => ref $for ? $for : undef
- });
+ for my $c (keys %$joinfree_cond) {
+ my ($colname) = $c =~ /^ (?: \Q$relalias.\E )? (.+)/x;
- } elsif (ref $cond eq 'HASH') {
+ unless ($relcol_list->{$colname}) {
+ push @$cond_cols, $colname;
+ next;
+ }
+
+ if (
+ ref $joinfree_cond->{$c}
+ and
+ ref $joinfree_cond->{$c} ne 'SCALAR'
+ and
+ ref $joinfree_cond->{$c} ne 'REF'
+ ) {
+ push @$cond_cols, $colname;
+ next;
+ }
+ }
+
+ return wantarray ? ($joinfree_cond, 0, $cond_cols) : $joinfree_cond;
+ }
+ else {
+ return wantarray ? ($crosstable_cond, 1) : $crosstable_cond;
+ }
+ }
+ elsif (ref $cond eq 'HASH') {
my %ret;
foreach my $k (keys %{$cond}) {
my $v = $cond->{$k};
} elsif (!defined $as) { # undef, i.e. "no reverse object"
$ret{$v} = undef;
} else {
- $ret{"${as}.${k}"} = "${for}.${v}";
+ $ret{"${as}.${k}"} = { -ident => "${for}.${v}" };
}
}
- return \%ret;
- } elsif (ref $cond eq 'ARRAY') {
- return [ map { $self->_resolve_condition($_, $as, $for) } @$cond ];
- } else {
- $self->throw_exception ("Can't handle condition $cond yet :(");
+
+ return wantarray
+ ? ( \%ret, ($obj_rel || !defined $as || ref $as) ? 0 : 1 )
+ : \%ret
+ ;
+ }
+ elsif (ref $cond eq 'ARRAY') {
+ my (@ret, $crosstable);
+ for (@$cond) {
+ my ($cond, $crosstab) = $self->_resolve_condition($_, $as, $for, $relname);
+ push @ret, $cond;
+ $crosstable ||= $crosstab;
+ }
+ return wantarray ? (\@ret, $crosstable) : \@ret;
+ }
+ else {
+ $self->throw_exception ("Can't handle condition $cond for relationship '$relname' yet :(");
}
}
-
# Accepts one or more relationships for the current source and returns an
# array of column names for each of those relationships. Column names are
# prefixed relative to the current source, in accordance with where they appear
# in the supplied relationships.
-
sub _resolve_prefetch {
- my ($self, $pre, $alias, $alias_map, $order, $collapse, $pref_path) = @_;
+ my ($self, $pre, $alias, $alias_map, $order, $pref_path) = @_;
$pref_path ||= [];
- if (not defined $pre) {
+ if (not defined $pre or not length $pre) {
return ();
}
elsif( ref $pre eq 'ARRAY' ) {
return
- map { $self->_resolve_prefetch( $_, $alias, $alias_map, $order, $collapse, [ @$pref_path ] ) }
+ map { $self->_resolve_prefetch( $_, $alias, $alias_map, $order, [ @$pref_path ] ) }
@$pre;
}
elsif( ref $pre eq 'HASH' ) {
my @ret =
map {
- $self->_resolve_prefetch($_, $alias, $alias_map, $order, $collapse, [ @$pref_path ] ),
+ $self->_resolve_prefetch($_, $alias, $alias_map, $order, [ @$pref_path ] ),
$self->related_source($_)->_resolve_prefetch(
- $pre->{$_}, "${alias}.$_", $alias_map, $order, $collapse, [ @$pref_path, $_] )
+ $pre->{$_}, "${alias}.$_", $alias_map, $order, [ @$pref_path, $_] )
} keys %$pre;
return @ret;
}
unless ref($rel_info->{cond}) eq 'HASH';
my $dots = @{[$as_prefix =~ m/\./g]} + 1; # +1 to match the ".${as_prefix}"
- if (my ($fail) = grep { @{[$_ =~ m/\./g]} == $dots }
- keys %{$collapse}) {
- my ($last) = ($fail =~ /([^\.]+)$/);
- carp (
- "Prefetching multiple has_many rels ${last} and ${pre} "
- .(length($as_prefix)
- ? "at the same level (${as_prefix}) "
- : "at top level "
- )
- . 'will explode the number of row objects retrievable via ->next or ->all. '
- . 'Use at your own risk.'
- );
- }
-
#my @col = map { (/^self\.(.+)$/ ? ("${as_prefix}.$1") : ()); }
# values %{$rel_info->{cond}};
- $collapse->{".${as_prefix}${pre}"} = [ $rel_source->_pri_cols ];
- # action at a distance. prepending the '.' allows simpler code
- # in ResultSet->_collapse_result
my @key = map { (/^foreign\.(.+)$/ ? ($1) : ()); }
keys %{$rel_info->{cond}};
+
push @$order, map { "${as}.$_" } @key;
if (my $rel_order = $rel_info->{attrs}{order_by}) {
}
}
+# Takes a selection list and generates a collapse-map representing
+# row-object fold-points. Every relationship is assigned a set of unique,
+# non-nullable columns (which may *not even be* from the same resultset)
+# and the collapser will use this information to correctly distinguish
+# data of individual to-be-row-objects.
+sub _resolve_collapse {
+ my ($self, $as, $as_fq_idx, $rel_chain, $parent_info) = @_;
+
+ # for comprehensible error messages put ourselves at the head of the relationship chain
+ $rel_chain ||= [ $self->source_name ];
+
+ # record top-level fully-qualified column index
+ $as_fq_idx ||= { %$as };
+
+ my ($my_cols, $rel_cols);
+ for (keys %$as) {
+ if ($_ =~ /^ ([^\.]+) \. (.+) /x) {
+ $rel_cols->{$1}{$2} = 1;
+ }
+ else {
+ $my_cols->{$_} = {}; # important for ||= below
+ }
+ }
+
+ my $relinfo;
+ # run through relationships, collect metadata, inject non-left fk-bridges from
+ # *INNER-JOINED* children (if any)
+ for my $rel (keys %$rel_cols) {
+ my $rel_src = $self->related_source ($rel);
+ my $inf = $self->relationship_info ($rel);
+
+ $relinfo->{$rel}{is_single} = $inf->{attrs}{accessor} && $inf->{attrs}{accessor} ne 'multi';
+ $relinfo->{$rel}{is_inner} = ( $inf->{attrs}{join_type} || '' ) !~ /^left/i;
+ $relinfo->{$rel}{rsrc} = $rel_src;
+
+ my $cond = $inf->{cond};
+
+ if (
+ ref $cond eq 'HASH'
+ and
+ keys %$cond
+ and
+ ! List::Util::first { $_ !~ /^foreign\./ } (keys %$cond)
+ and
+ ! List::Util::first { $_ !~ /^self\./ } (values %$cond)
+ ) {
+ for my $f (keys %$cond) {
+ my $s = $cond->{$f};
+ $_ =~ s/^ (?: foreign | self ) \.//x for ($f, $s);
+ $relinfo->{$rel}{fk_map}{$s} = $f;
+
+ $my_cols->{$s} ||= { via_fk => "$rel.$f" } # need to know source from *our* pov
+ if ($relinfo->{$rel}{is_inner} && defined $rel_cols->{$rel}{$f}); # only if it is inner and in fact selected of course
+ }
+ }
+ }
+
+ # if the parent is already defined, assume all of its related FKs are selected
+ # (even if they in fact are NOT in the select list). Keep a record of what we
+ # assumed, and if any such phantom-column becomes part of our own collapser,
+ # throw everything assumed-from-parent away and replace with the collapser of
+ # the parent (whatever it may be)
+ my $assumed_from_parent;
+ unless ($parent_info->{underdefined}) {
+ $assumed_from_parent->{columns} = { map
+ # only add to the list if we do not already select said columns
+ { ! exists $my_cols->{$_} ? ( $_ => 1 ) : () }
+ values %{$parent_info->{rel_condition} || {}}
+ };
+
+ $my_cols->{$_} = { via_collapse => $parent_info->{collapse_on} }
+ for keys %{$assumed_from_parent->{columns}};
+ }
+
+ # get colinfo for everything
+ if ($my_cols) {
+ $my_cols->{$_}{colinfo} = (
+ $self->has_column ($_) ? $self->column_info ($_) : undef
+ ) for keys %$my_cols;
+ }
+
+ my $collapse_map;
+
+ # try to resolve based on our columns (plus already inserted FK bridges)
+ if (
+ $my_cols
+ and
+ my $uset = $self->_unique_column_set ($my_cols)
+ ) {
+ # see if the resulting collapser relies on any implied columns,
+ # and fix stuff up if this is the case
+
+ my $parent_collapser_used;
+
+ if (List::Util::first
+ { exists $assumed_from_parent->{columns}{$_} }
+ keys %$uset
+ ) {
+ # remove implied stuff from the uset, we will inject the equivalent collapser a bit below
+ delete @{$uset}{keys %{$assumed_from_parent->{columns}}};
+ $parent_collapser_used = 1;
+ }
+
+ $collapse_map->{-collapse_on} = {
+ %{ $parent_collapser_used ? $parent_info->{collapse_on} : {} },
+ (map
+ {
+ my $fqc = join ('.',
+ @{$rel_chain}[1 .. $#$rel_chain],
+ ( $my_cols->{$_}{via_fk} || $_ ),
+ );
+
+ $fqc => $as_fq_idx->{$fqc};
+ }
+ keys %$uset
+ ),
+ };
+ }
+
+ # don't know how to collapse - keep descending down 1:1 chains - if
+ # a related non-LEFT 1:1 is resolvable - its condition will collapse us
+ # too
+ unless ($collapse_map->{-collapse_on}) {
+ my @candidates;
+
+ for my $rel (keys %$relinfo) {
+ next unless ($relinfo->{$rel}{is_single} && $relinfo->{$rel}{is_inner});
+
+ if ( my $rel_collapse = $relinfo->{$rel}{rsrc}->_resolve_collapse (
+ $rel_cols->{$rel},
+ $as_fq_idx,
+ [ @$rel_chain, $rel ],
+ { underdefined => 1 }
+ )) {
+ push @candidates, $rel_collapse->{-collapse_on};
+ }
+ }
+
+ # get the set with least amount of columns
+ # FIXME - maybe need to implement a data type order as well (i.e. prefer several ints
+ # to a single varchar)
+ if (@candidates) {
+ ($collapse_map->{-collapse_on}) = sort { keys %$a <=> keys %$b } (@candidates);
+ }
+ }
+
+ # Still dont know how to collapse - see if the parent passed us anything
+ # (i.e. reuse collapser over 1:1)
+ unless ($collapse_map->{-collapse_on}) {
+ $collapse_map->{-collapse_on} = $parent_info->{collapse_on}
+ if $parent_info->{collapser_reusable};
+ }
+
+
+ # stop descending into children if we were called by a parent for first-pass
+ # and don't despair if nothing was found (there may be other parallel branches
+ # to dive into)
+ if ($parent_info->{underdefined}) {
+ return $collapse_map->{-collapse_on} ? $collapse_map : undef
+ }
+ # nothing down the chain resolved - can't calculate a collapse-map
+ elsif (! $collapse_map->{-collapse_on}) {
+ $self->throw_exception ( sprintf
+ "Unable to calculate a definitive collapse column set for %s%s: fetch more unique non-nullable columns",
+ $self->source_name,
+ @$rel_chain > 1
+ ? sprintf (' (last member of the %s chain)', join ' -> ', @$rel_chain )
+ : ''
+ ,
+ );
+ }
+
+
+ # If we got that far - we are collapsable - GREAT! Now go down all children
+ # a second time, and fill in the rest
+
+ for my $rel (keys %$relinfo) {
+
+ $collapse_map->{$rel} = $relinfo->{$rel}{rsrc}->_resolve_collapse (
+ { map { $_ => 1 } ( keys %{$rel_cols->{$rel}} ) },
+
+ $as_fq_idx,
+
+ [ @$rel_chain, $rel],
+
+ {
+ collapse_on => { %{$collapse_map->{-collapse_on}} },
+
+ rel_condition => $relinfo->{$rel}{fk_map},
+
+ # if this is a 1:1 our own collapser can be used as a collapse-map
+ # (regardless of left or not)
+ collapser_reusable => $relinfo->{$rel}{is_single},
+ },
+ );
+ }
+
+ return $collapse_map;
+}
+
+sub _unique_column_set {
+ my ($self, $cols) = @_;
+
+ my %unique = $self->unique_constraints;
+
+ # always prefer the PK first, and then shortest constraints first
+ USET:
+ for my $set (delete $unique{primary}, sort { @$a <=> @$b } (values %unique) ) {
+ next unless $set && @$set;
+
+ for (@$set) {
+ next USET unless ($cols->{$_} && $cols->{$_}{colinfo} && !$cols->{$_}{colinfo}{is_nullable} );
+ }
+
+ return { map { $_ => 1 } @$set };
+ }
+
+ return undef;
+}
+
+# Takes an arrayref of {as} dbic column aliases and the collapse and select
+# attributes from the same $rs (the slector requirement is a temporary
+# workaround), and returns a coderef capable of:
+# my $me_pref_clps = $coderef->([$rs->cursor->next])
+# Where the $me_pref_clps arrayref is the future argument to
+# ::ResultSet::_collapse_result.
+#
+# $me_pref_clps->[0] is always returned (even if as an empty hash with no
+# rowdata), however branches of related data in $me_pref_clps->[1] may be
+# pruned short of what was originally requested based on {as}, depending
+# on:
+#
+# * If collapse is requested, a definitive collapse map is calculated for
+# every relationship "fold-point", consisting of a set of values (which
+# may not even be contained in the future 'me' of said relationship
+# (for example a cd.artist_id defines the related inner-joined artist)).
+# Thus a definedness check is carried on all collapse-condition values
+# and if at least one is undef it is assumed that we are dealing with a
+# NULLed right-side of a left-join, so we don't return a related data
+# container at all, which implies no related objects
+#
+# * If we are not collapsing, there is no constraint on having a selector
+# uniquely identifying all possible objects, and the user might have very
+# well requested a column that just *happens* to be all NULLs. What we do
+# in this case is fallback to the old behavior (which is a potential FIXME)
+# by always returning a data container, but only filling it with columns
+# IFF at least one of them is defined. This way we do not get an object
+# with a bunch of has_column_loaded to undef, but at the same time do not
+# further relationships based off this "null" object (e.g. in case the user
+# deliberately skipped link-table values). I am pretty sure there are some
+# tests that codify this behavior, need to find the exact testname.
+#
+# For an example of this coderef in action (and to see its guts) look at
+# t/prefetch/_internals.t
+#
+# This is a huge performance win, as we call the same code for
+# every row returned from the db, thus avoiding repeated method
+# lookups when traversing relationships
+#
+# Also since the coderef is completely stateless (the returned structure is
+# always fresh on every new invocation) this is a very good opportunity for
+# memoization if further speed improvements are needed
+#
+# The way we construct this coderef is somewhat fugly, although I am not
+# sure if the string eval is *that* bad of an idea. The alternative is to
+# have a *very* large number of anon coderefs calling each other in a twisty
+# maze, whereas the current result is a nice, smooth, single-pass function.
+# In any case - the output of this thing is meticulously micro-tested, so
+# any sort of rewrite should be relatively easy
+#
+sub _mk_row_parser {
+ my ($self, $as, $with_collapse, $select) = @_;
+
+ my $as_indexed = { map
+ { $as->[$_] => $_ }
+ ( 0 .. $#$as )
+ };
+
+ # calculate collapse fold-points if needed
+ my $collapse_on = do {
+ # FIXME
+ # only consider real columns (not functions) during collapse resolution
+ # this check shouldn't really be here, as fucktards are not supposed to
+ # alias random crap to existing column names anyway, but still - just in
+ # case (also saves us from select/as mismatches which need fixing as well...)
+
+ my $plain_as = { %$as_indexed };
+ for (keys %$plain_as) {
+ delete $plain_as->{$_} if ref $select->[$plain_as->{$_}];
+ }
+ $self->_resolve_collapse ($plain_as);
+
+ } if $with_collapse;
+
+ my $perl = $self->__visit_as ($as_indexed, $collapse_on);
+ my $cref = eval "sub { $perl }"
+ or die "Oops! _mk_row_parser generated invalid perl:\n$@\n\n$perl\n";
+ return $cref;
+}
+
+{
+ my $visit_as_dumper; # keep our own DD object around so we don't have to fitz with quoting
+
+ sub __visit_as {
+ my ($self, $as, $collapse_on, $known_defined) = @_;
+ $known_defined ||= {};
+
+ # prepopulate the known defined map with our own collapse value positions
+ # the rationale is that if an Artist needs column 0 to be uniquely
+ # identified, and related CDs need columns 0 and 1, by the time we get to
+ # CDs we already know that column 0 is defined (otherwise there would be
+ # no related CDs as there is no Artist in the 1st place). So we use this
+ # index to cut on repetitive defined() checks.
+ $known_defined->{$_}++ for ( values %{$collapse_on->{-collapse_on} || {}} );
+
+ my $my_cols = {};
+ my $rel_cols;
+ for (keys %$as) {
+ if ($_ =~ /^ ([^\.]+) \. (.+) /x) {
+ $rel_cols->{$1}{$2} = $as->{$_};
+ }
+ else {
+ $my_cols->{$_} = $as->{$_};
+ }
+ }
+
+ my @relperl;
+ for my $rel (sort keys %$rel_cols) {
+ my $rel_node = $self->__visit_as($rel_cols->{$rel}, $collapse_on->{$rel}, {%$known_defined} );
+
+ my @null_checks;
+ if ($collapse_on->{$rel}{-collapse_on}) {
+ @null_checks = map
+ { "(! defined '__VALPOS__${_}__')" }
+ ( grep
+ { ! $known_defined->{$_} }
+ ( sort
+ { $a <=> $b }
+ values %{$collapse_on->{$rel}{-collapse_on}}
+ )
+ )
+ ;
+ }
+
+ if (@null_checks) {
+ push @relperl, sprintf ( '(%s) ? () : ( %s => %s )',
+ join (' || ', @null_checks ),
+ $rel,
+ $rel_node,
+ );
+ }
+ else {
+ push @relperl, "$rel => $rel_node";
+ }
+ }
+ my $rels = @relperl
+ ? sprintf ('{ %s }', join (',', @relperl))
+ : 'undef'
+ ;
+
+ my $me = {
+ map { $_ => "__VALPOS__$my_cols->{$_}__" } (keys %$my_cols)
+ };
+
+ my $clps = undef; # funny thing, but this prevents a memory leak, I guess it's Data::Dumper#s fault (mo)
+ $clps = [
+ map { "__VALPOS__${_}__" } ( sort { $a <=> $b } (values %{$collapse_on->{-collapse_on}}) )
+ ] if $collapse_on->{-collapse_on};
+
+ # we actually will be producing functional perl code here,
+ # thus no second-guessing of what these globals might have
+ # been set to. DO NOT CHANGE!
+ $visit_as_dumper ||= do {
+ require Data::Dumper;
+ Data::Dumper->new([])
+ ->Purity (1)
+ ->Pad ('')
+ ->Useqq (0)
+ ->Terse (1)
+ ->Quotekeys (1)
+ ->Deepcopy (1)
+ ->Deparse (0)
+ ->Maxdepth (0)
+ ->Indent (0)
+ };
+ for ($me, $clps) {
+ $_ = $visit_as_dumper->Values ([$_])->Dump;
+ }
+
+ unless ($collapse_on->{-collapse_on}) { # we are not collapsing, insert a definedness check on 'me'
+ $me = sprintf ( '(%s) ? %s : {}',
+ join (' || ', map { "( defined '__VALPOS__${_}__')" } (sort { $a <=> $b } values %$my_cols) ),
+ $me,
+ );
+ }
+
+ my @rv_list = ($me, $rels, $clps);
+ pop @rv_list while ($rv_list[-1] eq 'undef'); # strip trailing undefs
+
+ # change the quoted placeholders to unquoted alias-references
+ $_ =~ s/ \' __VALPOS__(\d+)__ \' /sprintf ('$_[0][%d]', $1)/gex
+ for grep { defined $_ } @rv_list;
+ return sprintf '[%s]', join (',', @rv_list);
+ }
+}
+
=head2 related_source
=over 4
if( !$self->has_relationship( $rel ) ) {
$self->throw_exception("No such relationship '$rel' on " . $self->source_name);
}
- return $self->schema->source($self->relationship_info($rel)->{source});
+
+ # if we are not registered with a schema - just use the prototype
+ # however if we do have a schema - ask for the source by name (and
+ # throw in the process if all fails)
+ if (my $schema = try { $self->schema }) {
+ $schema->source($self->relationship_info($rel)->{source});
+ }
+ else {
+ my $class = $self->relationship_info($rel)->{class};
+ $self->ensure_class_loaded($class);
+ $class->result_source_instance;
+ }
}
=head2 related_class
});
}
-{
- my $global_phase_destroy;
-
- END { $global_phase_destroy++ }
-
- sub DESTROY {
- return if $global_phase_destroy;
+my $global_phase_destroy;
+sub DESTROY {
+ return if $global_phase_destroy ||= in_global_destruction;
######
# !!! ACHTUNG !!!!
# we are trying to save to reattach back to the source we are destroying.
# The relevant code checking refcounts is in ::Schema::DESTROY()
- # if we are not a schema instance holder - we don't matter
- return if(
- ! ref $_[0]->{schema}
- or
- isweak $_[0]->{schema}
- );
+ # if we are not a schema instance holder - we don't matter
+ return if(
+ ! ref $_[0]->{schema}
+ or
+ isweak $_[0]->{schema}
+ );
- # weaken our schema hold forcing the schema to find somewhere else to live
+ # weaken our schema hold forcing the schema to find somewhere else to live
+ # during global destruction (if we have not yet bailed out) this will throw
+ # which will serve as a signal to not try doing anything else
+ # however beware - on older perls the exception seems randomly untrappable
+ # due to some weird race condition during thread joining :(((
+ local $@;
+ eval {
weaken $_[0]->{schema};
- # if schema is still there reintroduce ourselves with strong refs back
+ # if schema is still there reintroduce ourselves with strong refs back to us
if ($_[0]->{schema}) {
my $srcregs = $_[0]->{schema}->source_registrations;
for (keys %$srcregs) {
+ next unless $srcregs->{$_};
$srcregs->{$_} = $_[0] if $srcregs->{$_} == $_[0];
}
}
- }
+
+ 1;
+ } or do {
+ $global_phase_destroy = 1;
+ };
+
+ return;
}
-sub STORABLE_freeze { nfreeze($_[0]->handle) }
+sub STORABLE_freeze { Storable::nfreeze($_[0]->handle) }
sub STORABLE_thaw {
my ($self, $cloning, $ice) = @_;
- %$self = %{ (thaw $ice)->resolve };
+ %$self = %{ (Storable::thaw($ice))->resolve };
}
=head2 throw_exception