X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FDBIx%2FClass%2FResultSource%2FRowParser.pm;h=6540dc70bc24013a050a198186946b7713dea712;hb=e5c6382908ee65577e53c0771629384d70959a3d;hp=d71ca309ea94467f83e39a3e495d74a956358219;hpb=4e9fc3f33df616fb7340d05e304ff985b9cce9cb;p=dbsrgits%2FDBIx-Class.git diff --git a/lib/DBIx/Class/ResultSource/RowParser.pm b/lib/DBIx/Class/ResultSource/RowParser.pm index d71ca30..6540dc7 100644 --- a/lib/DBIx/Class/ResultSource/RowParser.pm +++ b/lib/DBIx/Class/ResultSource/RowParser.pm @@ -4,38 +4,45 @@ package # hide from the pauses use strict; use warnings; -use Try::Tiny; -use List::Util 'first'; -use B 'perlstring'; +use base 'DBIx::Class'; + +use DBIx::Class::ResultSource::RowParser::Util qw( + assemble_simple_parser + assemble_collapsing_parser +); +use DBIx::Class::_Util qw( DUMMY_ALIASPAIR dbic_internal_try dbic_internal_catch ); + +use DBIx::Class::Carp; + +# FIXME - this should go away +# instead Carp::Skip should export usable keywords or something like that +my $unique_carper; +BEGIN { $unique_carper = \&carp_unique } use namespace::clean; -use base 'DBIx::Class'; +# Accepts a prefetch map (one or more relationships for the current source), +# returns a set of select/as pairs for each of those relationships. Columns +# are fully qualified inflation_slot names +sub _resolve_selection_from_prefetch { + my ($self, $pre, $alias_map, $pref_path) = @_; -# Accepts one or more relationships for the current source and returns an -# array of column names for each of those relationships. Column names are -# prefixed relative to the current source, in accordance with where they appear -# in the supplied relationships. -sub _resolve_prefetch { - my ($self, $pre, $alias, $alias_map, $order, $pref_path) = @_; + # internal recursion marker $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; + map { $self->_resolve_selection_from_prefetch( $_, $alias_map, [ @$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, $_] ) + $self->_resolve_selection_from_prefetch($_, $alias_map, [ @$pref_path ] ), + $self->related_source($_)->_resolve_selection_from_prefetch( + $pre->{$_}, $alias_map, [ @$pref_path, $_] ) } keys %$pre; - return @ret; } elsif( ref $pre ) { $self->throw_exception( @@ -43,103 +50,196 @@ sub _resolve_prefetch { } else { my $p = $alias_map; - $p = $p->{$_} for (@$pref_path, $pre); + $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}}; + # this shift() is critical - it is what allows prefetch => [ (foo) x 2 ] to work + my $src_alias = shift @{$p->{-join_aliases}}; + + # ordered [select => as] pairs + map { [ + "${src_alias}.$_" => join ( '.', + @$pref_path, + $pre, + $_, + ) + ] } $self->related_source($pre)->columns; + } +} + +sub _resolve_prefetch { + carp_unique( + 'There is no good reason to call this internal deprecated method - ' + . 'please open a ticket detailing your usage, so that a better plan can ' + . 'be devised for your case. In either case _resolve_prefetch() is ' + . 'deprecated in favor of _resolve_selection_from_prefetch(), which has ' + . 'a greatly simplified arglist.' + ); - my $rel_info = $self->relationship_info( $pre ); - $self->throw_exception( $self->source_name . " has no such relationship '$pre'" ) - unless $rel_info; + $_[0]->_resolve_selection_from_prefetch( $_[1], $_[3] ); +} - my $as_prefix = ($alias =~ /^.*?\.(.+)$/ ? $1.'.' : ''); - return map { [ "${as}.$_", "${as_prefix}${pre}.$_", ] } - $self->related_source($pre)->columns; - } +# Takes an arrayref of {as} dbic column aliases and the collapse and select +# attributes from the same $rs (the selector requirement is a temporary +# workaround... I hope), and returns a coderef capable of: +# my $me_pref_clps = $coderef->([$rs->cursor->next/all]) +# Where the $me_pref_clps arrayref is the future argument to inflate_result() +# +# For an example of this coderef in action (and to see its guts) look at +# t/resultset/rowparser_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 the result is +# really worth it. The final coderef does not perform any kind of recursion - +# the entire nested structure constructor is rolled out into a single scope. +# +# In any case - the output of this thing is meticulously micro-tested, so +# any sort of adjustment/rewrite should be relatively easy (fsvo relatively) +# +sub _mk_row_parser { + # $args and $attrs are separated to delineate what is core collapser stuff and + # what is dbic $rs specific + my ($self, $args, $attrs) = @_; + + die "HRI without pruning makes zero sense" + if ( $args->{hri_style} && ! $args->{prune_null_branches} ); + + my %common = ( + hri_style => $args->{hri_style}, + prune_null_branches => $args->{prune_null_branches}, + val_index => { map + { $args->{inflate_map}[$_] => $_ } + ( 0 .. $#{$args->{inflate_map}} ) + }, + ); + + my $src = (! $args->{collapse} ) ? assemble_simple_parser(\%common) : do { + my $collapse_map = $self->_resolve_collapse ({ + # 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 + # FIXME !!!! - this does not yet deal with unbalanced selectors correctly + # (it is now trivial as the attrs specify where things go out of sync + # needs MOAR tests) + as => { map + { ref $attrs->{select}[$common{val_index}{$_}] ? () : ( $_ => $common{val_index}{$_} ) } + keys %{$common{val_index}} + }, + premultiplied => $args->{premultiplied}, + }); + + assemble_collapsing_parser({ + %common, + collapse_map => $collapse_map, + }); + }; + + utf8::upgrade($src) + if DBIx::Class::_ENV_::STRESSTEST_UTF8_UPGRADE_GENERATED_COLLAPSER_SOURCE; + + $src; } -# Takes a selection list and generates a collapse-map representing + +# Takes an arrayref selection list and generates a collapse-map representing # row-object fold-points. Every relationship is assigned a set of unique, # non-nullable columns (which may *not even be* from the same resultset) # and the collapser will use this information to correctly distinguish -# data of individual to-be-row-objects. +# data of individual to-be-row-objects. See t/resultset/rowparser_internals.t +# for extensive RV examples sub _resolve_collapse { - my ($self, $as, $as_fq_idx, $rel_chain, $parent_info, $node_idx_ref) = @_; + my ($self, $args, $common_args) = @_; # for comprehensible error messages put ourselves at the head of the relationship chain - $rel_chain ||= [ $self->source_name ]; + $args->{_rel_chain} ||= [ $self->source_name ]; - # record top-level fully-qualified column index - $as_fq_idx ||= { %$as }; + # record top-level fully-qualified column index, signify toplevelness + unless ($common_args->{_as_fq_idx}) { + $common_args->{_as_fq_idx} = { %{$args->{as}} }; + $args->{_is_top_level} = 1; + }; - my ($my_cols, $rel_cols); - for (keys %$as) { + my ($my_cols, $rel_cols, $native_cols); + for (keys %{$args->{as}}) { if ($_ =~ /^ ([^\.]+) \. (.+) /x) { $rel_cols->{$1}{$2} = 1; } else { - $my_cols->{$_} = {}; # important for ||= below + $native_cols->{$_} = $my_cols->{$_} = {}; # important for ||='s below } } my $relinfo; - # run through relationships, collect metadata, inject non-left fk-bridges from - # *INNER-JOINED* children (if any) + # run through relationships, collect metadata for my $rel (keys %$rel_cols) { - my $rel_src = __get_related_source($self, $rel, $rel_cols->{$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; + $relinfo->{$rel} = { + is_single => ( $inf->{attrs}{accessor} && $inf->{attrs}{accessor} ne 'multi' ), + is_inner => ( ( $inf->{attrs}{join_type} || '' ) !~ /^left/i), + rsrc => $self->related_source($rel), + fk_map => ( + dbic_internal_try { + $self->_resolve_relationship_condition( + rel_name => $rel, + + # an API where these are optional would be too cumbersome, + # instead always pass in some dummy values + DUMMY_ALIASPAIR, + )->{identity_map}, + } + dbic_internal_catch { - my $cond = $inf->{cond}; + $unique_carper->( + "Resolution of relationship '$rel' failed unexpectedly, " + . 'please relay the following error and seek assistance via ' + . DBIx::Class::_ENV_::HELP_URL . ". Encountered error: $_" + ); - if ( - ref $cond eq 'HASH' - and - keys %$cond - and - ! first { $_ !~ /^foreign\./ } (keys %$cond) - and - ! 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; - - # need to know source from *our* pov, hence $rel. - $my_cols->{$s} ||= { via_fk => "$rel.$f" } if ( - defined $rel_cols->{$rel}{$f} # in fact selected - and - $relinfo->{$rel}{is_inner} - ); - } + # RV + +{} + } + ), + }; + } + + # inject non-left fk-bridges from *INNER-JOINED* children (if any) + for my $rel (grep { $relinfo->{$_}{is_inner} } keys %$relinfo) { + my $ri = $relinfo->{$rel}; + for (keys %{$ri->{fk_map}} ) { + # need to know source from *our* pov, hence $rel.col + $my_cols->{$_} ||= { via_fk => "$rel.$ri->{fk_map}{$_}" } + if defined $rel_cols->{$rel}{$ri->{fk_map}{$_}} # in fact selected } } - # if the parent is already defined, assume all of its related FKs are selected + # if the parent is already defined *AND* we have an inner reverse relationship + # (i.e. do not exist without it) , 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}}; + if ( ! $args->{_parent_info}{underdefined} and ! $args->{_parent_info}{rev_rel_is_optional} ) { + for my $col ( values %{$args->{_parent_info}{rel_condition} || {}} ) { + next if exists $my_cols->{$col}; + $my_cols->{$col} = {}; + $assumed_from_parent->{columns}{$col}++; + } } # get colinfo for everything @@ -150,8 +250,58 @@ sub _resolve_collapse { my $collapse_map; - # try to resolve based on our columns (plus already inserted FK bridges) + # first try to reuse the parent's collapser (i.e. reuse collapser over 1:1) + # (makes for a leaner coderef later) + if( + ! $collapse_map->{-identifying_columns} + and + $args->{_parent_info}{collapser_reusable} + ) { + $collapse_map->{-identifying_columns} = $args->{_parent_info}{collapse_on_idcols} + } + + # Still don't know how to collapse - in case we are a *single* relationship + # AND our parent is defined AND we have any *native* non-nullable pieces: then + # we are still good to go + # NOTE: it doesn't matter if the nonnullable set is unique or not - it will be + # made unique by the parents identifying cols + if( + ! $collapse_map->{-identifying_columns} + and + $args->{_parent_info}{is_single} + and + @{ $args->{_parent_info}{collapse_on_idcols} } + and + ( my @native_nonnull_cols = grep { + $native_cols->{$_}{colinfo} + and + ! $native_cols->{$_}{colinfo}{is_nullable} + } keys %$native_cols ) + ) { + + $collapse_map->{-identifying_columns} = [ __unique_numlist( + @{ $args->{_parent_info}{collapse_on_idcols}||[] }, + + # FIXME - we don't really need *all* of the columns, $our_nonnull_cols[0] + # is sufficient. However map the entire thing to engage the extra nonnull + # explicit checks, just to be on the safe side + # Remove some day in the future + (map + { + $common_args->{_as_fq_idx}{join ('.', + @{$args->{_rel_chain}}[1 .. $#{$args->{_rel_chain}}], + $_, + )} + } + @native_nonnull_cols + ), + )]; + } + + # Still don't know how to collapse - try to resolve based on our columns (plus already inserted FK bridges) if ( + ! $collapse_map->{-identifying_columns} + and $my_cols and my $idset = $self->_identifying_column_set ({map { $_ => $my_cols->{$_}{colinfo} } keys %$my_cols}) @@ -160,38 +310,38 @@ sub _resolve_collapse { # and fix stuff up if this is the case my @reduced_set = grep { ! $assumed_from_parent->{columns}{$_} } @$idset; - $collapse_map->{-node_id} = __unique_numlist( - (@reduced_set != @$idset) ? @{$parent_info->{collapse_on}} : (), + $collapse_map->{-identifying_columns} = [ __unique_numlist( + @{ $args->{_parent_info}{collapse_on_idcols}||[] }, + (map { my $fqc = join ('.', - @{$rel_chain}[1 .. $#$rel_chain], + @{$args->{_rel_chain}}[1 .. $#{$args->{_rel_chain}}], ( $my_cols->{$_}{via_fk} || $_ ), ); - $as_fq_idx->{$fqc}; + $common_args->{_as_fq_idx}->{$fqc}; } @reduced_set ), - ); + )]; } # Stil 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 ($collapse_map->{-node_id}) { + unless ($collapse_map->{-identifying_columns}) { 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->{-node_id}; + if ( my $rel_collapse = $relinfo->{$rel}{rsrc}->_resolve_collapse ({ + as => $rel_cols->{$rel}, + _rel_chain => [ @{$args->{_rel_chain}}, $rel ], + _parent_info => { underdefined => 1 }, + }, $common_args)) { + push @candidates, $rel_collapse->{-identifying_columns}; } } @@ -199,30 +349,106 @@ sub _resolve_collapse { # FIXME - maybe need to implement a data type order as well (i.e. prefer several ints # to a single varchar) if (@candidates) { - ($collapse_map->{-node_id}) = sort { scalar @$a <=> scalar @$b } (@candidates); + ($collapse_map->{-identifying_columns}) = sort { scalar @$a <=> scalar @$b } (@candidates); } } - # Still dont know how to collapse - see if the parent passed us anything - # (i.e. reuse collapser over 1:1) - unless ($collapse_map->{-node_id}) { - $collapse_map->{-node_id} = $parent_info->{collapse_on} - if $parent_info->{collapser_reusable}; + # Stil don't know how to collapse, and we are the root node. Last ditch + # effort in case we are *NOT* premultiplied. + # Run through *each multi* all the way down, left or not, and all + # *left* singles (a single may become a multi underneath) . When everything + # gets back see if all the rels link to us definitively. If this is the + # case we are good - either one of them will define us, or if all are NULLs + # we know we are "unique" due to the "non-premultiplied" check + if ( + ! $collapse_map->{-identifying_columns} + and + ! $args->{premultiplied} + and + $args->{_is_top_level} + ) { + my (@collapse_sets, $uncollapsible_chain); + + for my $rel (keys %$relinfo) { + + # we already looked at these higher up + next if ($relinfo->{$rel}{is_single} && $relinfo->{$rel}{is_inner}); + + if (my $clps = $relinfo->{$rel}{rsrc}->_resolve_collapse ({ + as => $rel_cols->{$rel}, + _rel_chain => [ @{$args->{_rel_chain}}, $rel ], + _parent_info => { underdefined => 1 }, + }, $common_args) ) { + + # for singles use the idcols wholesale (either there or not) + if ($relinfo->{$rel}{is_single}) { + push @collapse_sets, $clps->{-identifying_columns}; + } + elsif (! $relinfo->{$rel}{fk_map}) { + $uncollapsible_chain = 1; + last; + } + else { + my $defined_cols_parent_side; + + for my $fq_col ( grep { /^$rel\.[^\.]+$/ } keys %{$args->{as}} ) { + my ($col) = $fq_col =~ /([^\.]+)$/; + + $defined_cols_parent_side->{$_} = $args->{as}{$fq_col} for grep + { $relinfo->{$rel}{fk_map}{$_} eq $col } + keys %{$relinfo->{$rel}{fk_map}} + ; + } + + if (my $set = $self->_identifying_column_set([ keys %$defined_cols_parent_side ]) ) { + push @collapse_sets, [ sort map { $defined_cols_parent_side->{$_} } @$set ]; + } + else { + $uncollapsible_chain = 1; + last; + } + } + } + else { + $uncollapsible_chain = 1; + last; + } + } + + unless ($uncollapsible_chain) { + # if we got here - we are good to go, but the construction is tricky + # since our children will want to include our collapse criteria - we + # don't give them anything (safe, since they are all collapsible on their own) + # in addition we record the individual collapse possibilities + # of all left children node collapsers, and merge them in the rowparser + # coderef later + $collapse_map->{-identifying_columns} = []; + $collapse_map->{-identifying_columns_variants} = [ sort { + (scalar @$a) <=> (scalar @$b) + or + ( + # Poor man's max() + ( sort { $b <=> $a } @$a )[0] + <=> + ( sort { $b <=> $a } @$b )[0] + ) + } @collapse_sets ]; + } } # 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->{-node_id} ? $collapse_map : undef + if ($args->{_parent_info}{underdefined}) { + return $collapse_map->{-identifying_columns} ? $collapse_map : undef } # nothing down the chain resolved - can't calculate a collapse-map - elsif (! $collapse_map->{-node_id}) { + elsif (! $collapse_map->{-identifying_columns}) { $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 ' -> ', @$rel_chain ) + @{$args->{_rel_chain}} > 1 + ? sprintf (' (last member of the %s chain)', join ' -> ', @{$args->{_rel_chain}} ) : '' , ); @@ -231,361 +457,58 @@ sub _resolve_collapse { # If we got that far - we are collapsable - GREAT! Now go down all children # a second time, and fill in the rest - $collapse_map->{-is_optional} = 1 if $parent_info->{is_optional}; - $collapse_map->{-node_index} = ${ $node_idx_ref ||= \do { my $x = 1 } }++; # this is *deliberately* not 0-based + $collapse_map->{-identifying_columns} = [ __unique_numlist( + @{ $args->{_parent_info}{collapse_on_idcols}||[] }, + @{ $collapse_map->{-identifying_columns} }, + )]; - my (@id_sets, $multis_in_chain); for my $rel (sort keys %$relinfo) { - $collapse_map->{$rel} = $relinfo->{$rel}{rsrc}->_resolve_collapse ( - { map { $_ => 1 } ( keys %{$rel_cols->{$rel}} ) }, - - $as_fq_idx, + $collapse_map->{$rel} = $relinfo->{$rel}{rsrc}->_resolve_collapse ({ + as => { map { $_ => 1 } ( keys %{$rel_cols->{$rel}} ) }, + _rel_chain => [ @{$args->{_rel_chain}}, $rel], + _parent_info => { + # shallow copy + collapse_on_idcols => [ @{$collapse_map->{-identifying_columns}} ], - [ @$rel_chain, $rel], + rel_condition => $relinfo->{$rel}{fk_map}, - { - collapse_on => [ @{$collapse_map->{-node_id}} ], + is_optional => ! $relinfo->{$rel}{is_inner}, - rel_condition => $relinfo->{$rel}{fk_map}, + is_single => $relinfo->{$rel}{is_single}, - is_optional => $collapse_map->{-is_optional}, + # if there is at least one *inner* reverse relationship ( meaning identity-only ) + # we can safely assume that the child can not exist without us + rev_rel_is_optional => ( + ( grep { + ($_->{attrs}{join_type}||'') !~ /^left/i + } values %{ $self->reverse_relationship_info($rel) } ) + ? 0 + : 1 + ), # 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}, + collapser_reusable => ( + $relinfo->{$rel}{is_single} + && + $relinfo->{$rel}{is_inner} + && + @{$collapse_map->{-identifying_columns}} + ) ? 1 : 0, }, - - $node_idx_ref, - ); + }, $common_args ); $collapse_map->{$rel}{-is_single} = 1 if $relinfo->{$rel}{is_single}; $collapse_map->{$rel}{-is_optional} ||= 1 unless $relinfo->{$rel}{is_inner}; - push @id_sets, @{ $collapse_map->{$rel}{-branch_id} }; } - $collapse_map->{-branch_id} = __unique_numlist( @id_sets, @{$collapse_map->{-node_id}} ); - return $collapse_map; } -# 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, $args) = @_; - - my $inflate_index = { map - { $args->{inflate_map}[$_] => $_ } - ( 0 .. $#{$args->{inflate_map}} ) - }; - - my ($parser_src); - if ($args->{collapse}) { - - my $collapse_map = $self->_resolve_collapse ( - # 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 - # FIXME !!!! - this does not yet deal with unbalanced selectors correctly - # (it is now trivial as the attrs specify where things go out of sync) - { map - { ref $args->{selection}[$inflate_index->{$_}] ? () : ( $_ => $inflate_index->{$_} ) } - keys %$inflate_index - } - ); - - my $top_branch_idx_list = join (', ', @{$collapse_map->{-branch_id}}); - - my $top_node_id_path = join ('', map - { "{'\xFF__IDVALPOS__${_}__\xFF'}" } - @{$collapse_map->{-node_id}} - ); - - my $rel_assemblers = __visit_infmap_collapse ( - $inflate_index, $collapse_map - ); - - $parser_src = sprintf (<<'EOS', $top_branch_idx_list, $top_node_id_path, $rel_assemblers); -### BEGIN STRING EVAL - - my ($rows_pos, $result_pos, $cur_row, @cur_row_ids, @collapse_idx, $is_new_res) = (0,0); - - # this loop is a bit arcane - the rationale is that the passed in - # $_[0] will either have only one row (->next) or will have all - # rows already pulled in (->all and/or unordered). Given that the - # result can be rather large - we reuse the same already allocated - # array, since the collapsed prefetch is smaller by definition. - # At the end we cut the leftovers away and move on. - while ($cur_row = - ( ( $rows_pos >= 0 and $_[0][$rows_pos++] ) or do { $rows_pos = -1; undef } ) - || - ($_[1] and $_[1]->()) - ) { - - $cur_row_ids[$_] = defined $cur_row->[$_] ? $cur_row->[$_] : "\xFF\xFFN\xFFU\xFFL\xFFL\xFF\xFF" - for (%1$s); # the top branch_id includes all id values - - $is_new_res = ! $collapse_idx[1]%2$s and ( - $_[1] and $result_pos and (unshift @{$_[2]}, $cur_row) and last - ); - - %3$s - - $_[0][$result_pos++] = $collapse_idx[1]%2$s - if $is_new_res; - } - - splice @{$_[0]}, $result_pos; # truncate the passed in array for cases of collapsing ->all() -### END STRING EVAL -EOS - - # change the quoted placeholders to unquoted alias-references - $parser_src =~ s/ \' \xFF__VALPOS__(\d+)__\xFF \' /"\$cur_row->[$1]"/gex; - $parser_src =~ s/ \' \xFF__IDVALPOS__(\d+)__\xFF \' /"\$cur_row_ids[$1]"/gex; - } - - else { - $parser_src = sprintf('$_ = %s for @{$_[0]}', __visit_infmap_simple( - $inflate_index, { rsrc => $self }), # need the $rsrc to determine left-ness - ); - - # change the quoted placeholders to unquoted alias-references - # !!! note - different var than the one above - $parser_src =~ s/ \' \xFF__VALPOS__(\d+)__\xFF \' /"\$_->[$1]"/gex; - } - - $parser_src; -} - -sub __visit_infmap_simple { - my ($val_idx, $args) = @_; - - my $my_cols = {}; - my $rel_cols; - for (keys %$val_idx) { - if ($_ =~ /^ ([^\.]+) \. (.+) /x) { - $rel_cols->{$1}{$2} = $val_idx->{$_}; - } - else { - $my_cols->{$_} = $val_idx->{$_}; - } - } - my @relperl; - for my $rel (sort keys %$rel_cols) { - - my $rel_rsrc = __get_related_source($args->{rsrc}, $rel, $rel_cols->{$rel}); - - #my $optional = $args->{is_optional}; - #$optional ||= ($args->{rsrc}->relationship_info($rel)->{attrs}{join_type} || '') =~ /^left/i; - - push @relperl, join ' => ', perlstring($rel), __visit_infmap_simple($rel_cols->{$rel}, { - non_top => 1, - #is_optional => $optional, - rsrc => $rel_rsrc, - }); - - # FIXME SUBOPTIMAL - disabled to satisfy t/resultset/inflate_result_api.t - #if ($optional and my @branch_null_checks = map - # { "(! defined '\xFF__VALPOS__${_}__\xFF')" } - # sort { $a <=> $b } values %{$rel_cols->{$rel}} - #) { - # $relperl[-1] = sprintf ( '(%s) ? ( %s => [] ) : ( %s )', - # join (' && ', @branch_null_checks ), - # perlstring($rel), - # $relperl[-1], - # ); - #} - } - - my $me_struct = keys %$my_cols - ? __visit_dump({ map { $_ => "\xFF__VALPOS__$my_cols->{$_}__\xFF" } (keys %$my_cols) }) - : 'undef' - ; - - return sprintf '[%s]', join (',', - $me_struct, - @relperl ? sprintf ('{ %s }', join (',', @relperl)) : (), - ); -} - -sub __visit_infmap_collapse { - - my ($val_idx, $collapse_map, $parent_info) = @_; - - my $my_cols = {}; - my $rel_cols; - for (keys %$val_idx) { - if ($_ =~ /^ ([^\.]+) \. (.+) /x) { - $rel_cols->{$1}{$2} = $val_idx->{$_}; - } - else { - $my_cols->{$_} = $val_idx->{$_}; - } - } - - my $sequenced_node_id = join ('', map - { "{'\xFF__IDVALPOS__${_}__\xFF'}" } - @{$collapse_map->{-node_id}} - ); - - my $me_struct = keys %$my_cols - ? __visit_dump([{ map { $_ => "\xFF__VALPOS__$my_cols->{$_}__\xFF" } (keys %$my_cols) }]) - : undef - ; - my $node_idx_ref = sprintf '$collapse_idx[%d]%s', $collapse_map->{-node_index}, $sequenced_node_id; - - my $parent_idx_ref = sprintf( '$collapse_idx[%d]%s[1]{%s}', - @{$parent_info}{qw/node_idx sequenced_node_id/}, - perlstring($parent_info->{relname}), - ) if $parent_info; - - my @src; - if ($collapse_map->{-node_index} == 1) { - push @src, sprintf( '%s ||= %s;', - $node_idx_ref, - $me_struct, - ) if $me_struct; - } - elsif ($collapse_map->{-is_single}) { - push @src, sprintf ( '%s ||= %s%s;', - $parent_idx_ref, - $node_idx_ref, - $me_struct ? " ||= $me_struct" : '', - ); - } - else { - push @src, sprintf('push @{%s}, %s%s unless %s;', - $parent_idx_ref, - $node_idx_ref, - $me_struct ? " ||= $me_struct" : '', - $node_idx_ref, - ); - } - - #my $known_defined = { %{ $parent_info->{known_defined} || {} } }; - #$known_defined->{$_}++ for @{$collapse_map->{-node_id}}; - - for my $rel (sort keys %$rel_cols) { - - push @src, sprintf( '%s[1]{%s} ||= [];', $node_idx_ref, perlstring($rel) ) - unless $collapse_map->{$rel}{-is_single}; - - push @src, __visit_infmap_collapse($rel_cols->{$rel}, $collapse_map->{$rel}, { - node_idx => $collapse_map->{-node_index}, - sequenced_node_id => $sequenced_node_id, - relname => $rel, - #known_defined => $known_defined, - }); - - # FIXME SUBOPTIMAL - disabled to satisfy t/resultset/inflate_result_api.t - #if ($collapse_map->{$rel}{-is_optional} and my @null_checks = map - # { "(! defined '\xFF__IDVALPOS__${_}__\xFF')" } - # sort { $a <=> $b } grep - # { ! $known_defined->{$_} } - # @{$collapse_map->{$rel}{-node_id}} - #) { - # $src[-1] = sprintf( '(%s) or %s', - # join (' || ', @null_checks ), - # $src[-1], - # ); - #} - } - - join "\n", @src; -} - # adding a dep on MoreUtils *just* for this is retarded sub __unique_numlist { - [ sort { $a <=> $b } keys %{ {map { $_ => 1 } @_ }} ] -} - -# This error must be thrown from two distinct codepaths, joining them is -# rather hard. Go for this hack instead. -sub __get_related_source { - my ($rsrc, $rel, $relcols) = @_; - try { - $rsrc->related_source ($rel) - } catch { - $rsrc->throw_exception(sprintf( - "Can't inflate prefetch into non-existent relationship '%s' from '%s', " - . "check the inflation specification (columns/as) ending in '...%s.%s'.", - $rel, - $rsrc->source_name, - $rel, - (sort { length($a) <=> length ($b) } keys %$relcols)[0], - ))}; -} - -# keep our own DD object around so we don't have to fitz with quoting -my $dumper_obj; -sub __visit_dump { - # we actually will be producing functional perl code here, - # thus no second-guessing of what these globals might have - # been set to. DO NOT CHANGE! - ($dumper_obj ||= do { - require Data::Dumper; - Data::Dumper->new([]) - ->Useperl (1) - ->Purity (1) - ->Pad ('') - ->Useqq (0) - ->Terse (1) - ->Quotekeys (1) - ->Deepcopy (0) - ->Deparse (0) - ->Maxdepth (0) - ->Indent (0) # faster but harder to read, perhaps leave at 1 ? - })->Values ([$_[0]])->Dump; + sort { $a <=> $b } keys %{ {map { $_ => 1 } @_ }} } 1;