X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FDBIx%2FClass%2FResultSource.pm;h=d33a74d58e65657e96a128014dc37c93fcf5235b;hb=b7ddb46dbf77846e735fc491e04b0db4337fe5c0;hp=31b7eec05ad447e87ad8d37cfb7d4f86aae814ad;hpb=fe0708a2d68b5d34b6bc6f7e70164c3e569f1dd0;p=dbsrgits%2FDBIx-Class-Historic.git diff --git a/lib/DBIx/Class/ResultSource.pm b/lib/DBIx/Class/ResultSource.pm index 31b7eec..d33a74d 100644 --- a/lib/DBIx/Class/ResultSource.pm +++ b/lib/DBIx/Class/ResultSource.pm @@ -3,17 +3,17 @@ package DBIx::Class::ResultSource; use strict; use warnings; -use base qw/DBIx::Class/; +use base qw/DBIx::Class::ResultSource::RowParser DBIx::Class/; use DBIx::Class::ResultSet; use DBIx::Class::ResultSourceHandle; -use DBIx::Class::Exception; use DBIx::Class::Carp; -use DBIx::Class::GlobalDestruction; +use Devel::GlobalDestruction; use Try::Tiny; use List::Util 'first'; use Scalar::Util qw/blessed weaken isweak/; + use namespace::clean; __PACKAGE__->mk_group_accessors(simple => qw/ @@ -94,7 +94,7 @@ You can retrieve the result source at runtime in the following ways: $schema->source($source_name); -=item From a Row object: +=item From a Result object: $row->result_source; @@ -133,7 +133,7 @@ sub new { =item Arguments: @columns -=item Return value: The ResultSource object +=item Return Value: L<$result_source|/new> =back @@ -146,7 +146,7 @@ pairs, uses the hashref as the L for that column. Repeated calls of this method will add more columns, not replace them. The column names given will be created as accessor methods on your -L objects. You can change the name of the accessor +L objects. You can change the name of the accessor by supplying an L in the column_info hash. If a column name beginning with a plus sign ('+col1') is provided, the @@ -299,7 +299,7 @@ L. =item Arguments: $colname, \%columninfo? -=item Return value: 1/0 (true/false) +=item Return Value: 1/0 (true/false) =back @@ -343,7 +343,7 @@ sub add_column { shift->add_columns(@_); } # DO NOT CHANGE THIS TO GLOB =item Arguments: $colname -=item Return value: 1/0 (true/false) +=item Return Value: 1/0 (true/false) =back @@ -364,7 +364,7 @@ sub has_column { =item Arguments: $colname -=item Return value: Hashref of info +=item Return Value: Hashref of info =back @@ -412,9 +412,9 @@ sub column_info { =over -=item Arguments: None +=item Arguments: none -=item Return value: Ordered list of column names +=item Return Value: Ordered list of column names =back @@ -438,7 +438,7 @@ sub columns { =item Arguments: \@colnames ? -=item Return value: Hashref of column name/info pairs +=item Return Value: Hashref of column name/info pairs =back @@ -512,7 +512,7 @@ sub columns_info { =item Arguments: @colnames -=item Return value: undefined +=item Return Value: not defined =back @@ -530,7 +530,7 @@ broken result source. =item Arguments: $colname -=item Return value: undefined +=item Return Value: not defined =back @@ -568,7 +568,7 @@ sub remove_column { shift->remove_columns(@_); } # DO NOT CHANGE THIS TO GLOB =item Arguments: @cols -=item Return value: undefined +=item Return Value: not defined =back @@ -602,9 +602,9 @@ sub set_primary_key { =over 4 -=item Arguments: None +=item Arguments: none -=item Return value: Ordered list of primary column names +=item Return Value: Ordered list of primary column names =back @@ -641,7 +641,7 @@ will be applied to the L of each L =item Arguments: $sequence_name -=item Return value: undefined +=item Return Value: not defined =back @@ -664,7 +664,7 @@ sub sequence { =item Arguments: $name?, \@colnames -=item Return value: undefined +=item Return Value: not defined =back @@ -730,7 +730,7 @@ sub add_unique_constraint { =item Arguments: @constraints -=item Return value: undefined +=item Return Value: not defined =back @@ -782,7 +782,7 @@ sub add_unique_constraints { =item Arguments: \@colnames -=item Return value: Constraint name +=item Return Value: Constraint name =back @@ -816,9 +816,9 @@ sub name_unique_constraint { =over 4 -=item Arguments: None +=item Arguments: none -=item Return value: Hash of unique constraint data +=item Return Value: Hash of unique constraint data =back @@ -840,9 +840,9 @@ sub unique_constraints { =over 4 -=item Arguments: None +=item Arguments: none -=item Return value: Unique constraint names +=item Return Value: Unique constraint names =back @@ -866,7 +866,7 @@ sub unique_constraint_names { =item Arguments: $constraintname -=item Return value: List of constraint columns +=item Return Value: List of constraint columns =back @@ -894,7 +894,7 @@ sub unique_constraint_columns { =item Arguments: $callback_name | \&callback_code -=item Return value: $callback_name | \&callback_code +=item Return Value: $callback_name | \&callback_code =back @@ -961,13 +961,39 @@ sub _invoke_sqlt_deploy_hook { } } +=head2 result_class + +=over 4 + +=item Arguments: $classname + +=item Return Value: $classname + +=back + + use My::Schema::ResultClass::Inflator; + ... + + use My::Schema::Artist; + ... + __PACKAGE__->result_class('My::Schema::ResultClass::Inflator'); + +Set the default result class for this source. You can use this to create +and use your own result inflator. See L +for more details. + +Please note that setting this to something like +L will make every result unblessed +and make life more difficult. Inflators like those are better suited to +temporary usage via L. + =head2 resultset =over 4 -=item Arguments: None +=item Arguments: none -=item Return value: $resultset +=item Return Value: L<$resultset|DBIx::Class::ResultSet> =back @@ -984,7 +1010,7 @@ but is cached from then on unless resultset_class changes. =item Arguments: $classname -=item Return value: $classname +=item Return Value: $classname =back @@ -1008,9 +1034,9 @@ exists. =over 4 -=item Arguments: \%attrs +=item Arguments: L<\%attrs|DBIx::Class::ResultSet/ATTRIBUTES> -=item Return value: \%attrs +=item Return Value: L<\%attrs|DBIx::Class::ResultSet/ATTRIBUTES> =back @@ -1021,8 +1047,35 @@ exists. $source->resultset_attributes({ order_by => [ 'id' ] }); Store a collection of resultset attributes, that will be set on every -L produced from this result source. For a full -list see L. +L produced from this result source. + +B: C comes with its own set of issues and +bugs! While C isn't deprecated per se, its usage is +not recommended! + +Since relationships use attributes to link tables together, the "default" +attributes you set may cause unpredictable and undesired behavior. Furthermore, +the defaults cannot be turned off, so you are stuck with them. + +In most cases, what you should actually be using are project-specific methods: + + package My::Schema::ResultSet::Artist; + use base 'DBIx::Class::ResultSet'; + ... + + # BAD IDEA! + #__PACKAGE__->resultset_attributes({ prefetch => 'tracks' }); + + # GOOD IDEA! + sub with_tracks { shift->search({}, { prefetch => 'tracks' }) } + + # in your code + $schema->resultset('Artist')->with_tracks->... + +This gives you the flexibility of not using it when you don't need it. + +For more complex situations, another solution would be to use a virtual view +via L. =cut @@ -1046,7 +1099,7 @@ sub resultset { =over 4 -=item Arguments: None +=item Arguments: none =item Result value: $name @@ -1082,9 +1135,9 @@ its class name. =over 4 -=item Arguments: None +=item Arguments: none -=item Return value: FROM clause +=item Return Value: FROM clause =back @@ -1102,9 +1155,9 @@ sub from { die 'Virtual method!' } =over 4 -=item Arguments: $schema +=item Arguments: L<$schema?|DBIx::Class::Schema> -=item Return value: A schema object +=item Return Value: L<$schema|DBIx::Class::Schema> =back @@ -1138,17 +1191,15 @@ sub schema { =over 4 -=item Arguments: None +=item Arguments: none -=item Return value: A Storage object +=item Return Value: L<$storage|DBIx::Class::Storage> =back $source->storage->debug(1); -Returns the storage handle for the current schema. - -See also: L +Returns the L for the current schema. =cut @@ -1158,13 +1209,13 @@ sub storage { shift->schema->storage; } =over 4 -=item Arguments: $relname, $related_source_name, \%cond, [ \%attrs ] +=item Arguments: $rel_name, $related_source_name, \%cond, \%attrs? -=item Return value: 1/true if it succeeded +=item Return Value: 1/true if it succeeded =back - $source->add_relationship('relname', 'related_source', $cond, $attrs); + $source->add_relationship('rel_name', 'related_source', $cond, $attrs); L describes a series of methods which create pre-defined useful types of relationships. Look there first @@ -1284,9 +1335,9 @@ sub add_relationship { =over 4 -=item Arguments: None +=item Arguments: none -=item Return value: List of relationship names +=item Return Value: L<@rel_names|DBIx::Class::Relationship> =back @@ -1304,29 +1355,29 @@ sub relationships { =over 4 -=item Arguments: $relname +=item Arguments: L<$rel_name|DBIx::Class::Relationship> -=item Return value: Hashref of relation data, +=item Return Value: L<\%rel_data|DBIx::Class::Relationship::Base/add_relationship> =back Returns a hash of relationship information for the specified relationship -name. The keys/values are as specified for L. +name. The keys/values are as specified for L. =cut sub relationship_info { - my ($self, $rel) = @_; - return $self->_relationships->{$rel}; + #my ($self, $rel) = @_; + return shift->_relationships->{+shift}; } =head2 has_relationship =over 4 -=item Arguments: $rel +=item Arguments: L<$rel_name|DBIx::Class::Relationship> -=item Return value: 1/0 (true/false) +=item Return Value: 1/0 (true/false) =back @@ -1335,17 +1386,17 @@ Returns true if the source has a relationship of this name, false otherwise. =cut sub has_relationship { - my ($self, $rel) = @_; - return exists $self->_relationships->{$rel}; + #my ($self, $rel) = @_; + return exists shift->_relationships->{+shift}; } =head2 reverse_relationship_info =over 4 -=item Arguments: $relname +=item Arguments: L<$rel_name|DBIx::Class::Relationship> -=item Return value: Hashref of relationship data +=item Return Value: L<\%rel_data|DBIx::Class::Relationship::Base/add_relationship> =back @@ -1544,12 +1595,12 @@ sub _resolve_join { , -join_path => [@$jpath, { $join => $as } ], -is_single => ( - $rel_info->{attrs}{accessor} - && + (! $rel_info->{attrs}{accessor}) + or first { $rel_info->{attrs}{accessor} eq $_ } (qw/single filter/) ), -alias => $as, - -relation_chain_depth => $seen->{-relation_chain_depth} || 0, + -relation_chain_depth => ( $seen->{-relation_chain_depth} || 0 ) + 1, }, scalar $self->_resolve_condition($rel_info->{cond}, $as, $alias, $join) ]; @@ -1566,9 +1617,9 @@ sub pk_depends_on { # having already been inserted. Takes the name of the relationship and a # hashref of columns of the related object. sub _pk_depends_on { - my ($self, $relname, $rel_data) = @_; + my ($self, $rel_name, $rel_data) = @_; - my $relinfo = $self->relationship_info($relname); + my $relinfo = $self->relationship_info($rel_name); # don't assume things if the relationship direction is specified return $relinfo->{attrs}{is_foreign_key_constraint} @@ -1583,7 +1634,7 @@ sub _pk_depends_on { # assume anything that references our PK probably is dependent on us # rather than vice versa, unless the far side is (a) defined or (b) # auto-increment - my $rel_source = $self->related_source($relname); + my $rel_source = $self->related_source($rel_name); foreach my $p ($self->primary_columns) { if (exists $keyhash->{$p}) { @@ -1611,7 +1662,7 @@ our $UNRESOLVABLE_CONDITION = \ '1 = 0'; # list of non-triviail values (notmally conditions) returned as a part # of a joinfree condition hash sub _resolve_condition { - my ($self, $cond, $as, $for, $relname) = @_; + my ($self, $cond, $as, $for, $rel_name) = @_; my $obj_rel = !!blessed $for; @@ -1622,7 +1673,7 @@ sub _resolve_condition { self_alias => $obj_rel ? $as : $for, foreign_alias => $relalias, self_resultsource => $self, - foreign_relname => $relname || ($obj_rel ? $as : $for), + foreign_relname => $rel_name || ($obj_rel ? $as : $for), self_rowobj => $obj_rel ? $for : undef }); @@ -1631,7 +1682,7 @@ sub _resolve_condition { # 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" + "A join-free condition returned for relationship '$rel_name' without a row-object to chain from" ) unless $obj_rel; # FIXME another sanity check @@ -1641,7 +1692,7 @@ sub _resolve_condition { first { $_ !~ /^\Q$relalias.\E.+/ } keys %$joinfree_cond ) { $self->throw_exception ( - "The join-free condition returned for relationship '$relname' must be a hash " + "The join-free condition returned for relationship '$rel_name' must be a hash " .'reference with all keys being valid columns on the related result source' ); } @@ -1658,7 +1709,7 @@ sub _resolve_condition { } # see which parts of the joinfree cond are conditionals - my $relcol_list = { map { $_ => 1 } $self->related_source($relname)->columns }; + my $relcol_list = { map { $_ => 1 } $self->related_source($rel_name)->columns }; for my $c (keys %$joinfree_cond) { my ($colname) = $c =~ /^ (?: \Q$relalias.\E )? (.+)/x; @@ -1735,511 +1786,14 @@ sub _resolve_condition { elsif (ref $cond eq 'ARRAY') { my (@ret, $crosstable); for (@$cond) { - my ($cond, $crosstab) = $self->_resolve_condition($_, $as, $for, $relname); + my ($cond, $crosstab) = $self->_resolve_condition($_, $as, $for, $rel_name); 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, $pref_path) = @_; - $pref_path ||= []; - - if (not defined $pre or not length $pre) { - return (); - } - elsif( ref $pre eq 'ARRAY' ) { - return - 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, $order, [ @$pref_path ] ), - $self->related_source($_)->_resolve_prefetch( - $pre->{$_}, "${alias}.$_", $alias_map, $order, [ @$pref_path, $_] ) - } keys %$pre; - return @ret; - } - elsif( ref $pre ) { - $self->throw_exception( - "don't know how to resolve prefetch reftype ".ref($pre)); - } - else { - my $p = $alias_map; - $p = $p->{$_} for (@$pref_path, $pre); - - $self->throw_exception ( - "Unable to resolve prefetch '$pre' - join alias map does not contain an entry for path: " - . join (' -> ', @$pref_path, $pre) - ) if (ref $p->{-join_aliases} ne 'ARRAY' or not @{$p->{-join_aliases}} ); - - my $as = shift @{$p->{-join_aliases}}; - - my $rel_info = $self->relationship_info( $pre ); - $self->throw_exception( $self->source_name . " has no such relationship '$pre'" ) - unless $rel_info; - my $as_prefix = ($alias =~ /^.*?\.(.+)$/ ? $1.'.' : ''); - my $rel_source = $self->related_source($pre); - - if ($rel_info->{attrs}{accessor} && $rel_info->{attrs}{accessor} eq 'multi') { - $self->throw_exception( - "Can't prefetch has_many ${pre} (join cond too complex)") - unless ref($rel_info->{cond}) eq 'HASH'; - my $dots = @{[$as_prefix =~ m/\./g]} + 1; # +1 to match the ".${as_prefix}" - - #my @col = map { (/^self\.(.+)$/ ? ("${as_prefix}.$1") : ()); } - # values %{$rel_info->{cond}}; - my @key = map { (/^foreign\.(.+)$/ ? ($1) : ()); } - keys %{$rel_info->{cond}}; - - push @$order, map { "${as}.$_" } @key; - - if (my $rel_order = $rel_info->{attrs}{order_by}) { - # this is kludgy and incomplete, I am well aware - # but the parent method is going away entirely anyway - # so sod it - my $sql_maker = $self->storage->sql_maker; - my ($orig_ql, $orig_qr) = $sql_maker->_quote_chars; - my $sep = $sql_maker->name_sep; - - # install our own quoter, so we can catch unqualified stuff - local $sql_maker->{quote_char} = ["\x00", "\xFF"]; - - my $quoted_prefix = "\x00${as}\xFF"; - - for my $chunk ( $sql_maker->_order_by_chunks ($rel_order) ) { - my @bind; - ($chunk, @bind) = @$chunk if ref $chunk; - - $chunk = "${quoted_prefix}${sep}${chunk}" - unless $chunk =~ /\Q$sep/; - - $chunk =~ s/\x00/$orig_ql/g; - $chunk =~ s/\xFF/$orig_qr/g; - push @$order, \[$chunk, @bind]; - } - } - } - - return map { [ "${as}.$_", "${as_prefix}${pre}.$_", ] } - $rel_source->columns; - } -} - -# Takes a selection list and generates a collapse-map representing -# row-object fold-points. Every relationship is assigned a set of unique, -# non-nullable columns (which may *not even be* from the same resultset) -# and the collapser will use this information to correctly distinguish -# data of individual to-be-row-objects. -sub _resolve_collapse { - my ($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); + $self->throw_exception ("Can't handle condition $cond for relationship '$rel_name' yet :("); } } @@ -2247,9 +1801,9 @@ sub _mk_row_parser { =over 4 -=item Arguments: $relname +=item Arguments: $rel_name -=item Return value: $source +=item Return Value: $source =back @@ -2280,9 +1834,9 @@ sub related_source { =over 4 -=item Arguments: $relname +=item Arguments: $rel_name -=item Return value: $classname +=item Return Value: $classname =back @@ -2302,9 +1856,9 @@ sub related_class { =over 4 -=item Arguments: None +=item Arguments: none -=item Return value: $source_handle +=item Return Value: L<$source_handle|DBIx::Class::ResultSourceHandle> =back @@ -2421,7 +1975,7 @@ Creates a new ResultSource object. Not normally called directly by end users. =item Arguments: 1/0 (default: 0) -=item Return value: 1/0 +=item Return Value: 1/0 =back @@ -2432,9 +1986,9 @@ metadata from storage as necessary. This is *deprecated*, and should not be used. It will be removed before 1.0. -=head1 AUTHORS +=head1 AUTHOR AND CONTRIBUTORS -Matt S. Trout +See L and L in DBIx::Class =head1 LICENSE