1 package # hide from the pauses
2 DBIx::Class::ResultSource::RowParser;
8 use List::Util qw(first max);
13 use base 'DBIx::Class';
15 # Accepts one or more relationships for the current source and returns an
16 # array of column names for each of those relationships. Column names are
17 # prefixed relative to the current source, in accordance with where they appear
18 # in the supplied relationships.
19 sub _resolve_prefetch {
20 my ($self, $pre, $alias, $alias_map, $order, $pref_path) = @_;
23 if (not defined $pre or not length $pre) {
26 elsif( ref $pre eq 'ARRAY' ) {
28 map { $self->_resolve_prefetch( $_, $alias, $alias_map, $order, [ @$pref_path ] ) }
31 elsif( ref $pre eq 'HASH' ) {
34 $self->_resolve_prefetch($_, $alias, $alias_map, $order, [ @$pref_path ] ),
35 $self->related_source($_)->_resolve_prefetch(
36 $pre->{$_}, "${alias}.$_", $alias_map, $order, [ @$pref_path, $_] )
41 $self->throw_exception(
42 "don't know how to resolve prefetch reftype ".ref($pre));
46 $p = $p->{$_} for (@$pref_path, $pre);
48 $self->throw_exception (
49 "Unable to resolve prefetch '$pre' - join alias map does not contain an entry for path: "
50 . join (' -> ', @$pref_path, $pre)
51 ) if (ref $p->{-join_aliases} ne 'ARRAY' or not @{$p->{-join_aliases}} );
53 my $as = shift @{$p->{-join_aliases}};
55 my $rel_info = $self->relationship_info( $pre );
56 $self->throw_exception( $self->source_name . " has no such relationship '$pre'" )
59 my $as_prefix = ($alias =~ /^.*?\.(.+)$/ ? $1.'.' : '');
61 return map { [ "${as}.$_", "${as_prefix}${pre}.$_", ] }
62 $self->related_source($pre)->columns;
66 # Takes an arrayref selection list and generates a collapse-map representing
67 # row-object fold-points. Every relationship is assigned a set of unique,
68 # non-nullable columns (which may *not even be* from the same resultset)
69 # and the collapser will use this information to correctly distinguish
70 # data of individual to-be-row-objects. See t/resultset/rowparser_internals.t
71 # for extensive RV examples
72 sub _resolve_collapse {
73 my ($self, $args, $common_args) = @_;
75 # for comprehensible error messages put ourselves at the head of the relationship chain
76 $args->{_rel_chain} ||= [ $self->source_name ];
78 # record top-level fully-qualified column index, start nodecount
80 _as_fq_idx => { %{$args->{as}} },
81 _node_idx => 1, # this is *deliberately* not 0-based
84 my ($my_cols, $rel_cols);
85 for (keys %{$args->{as}}) {
86 if ($_ =~ /^ ([^\.]+) \. (.+) /x) {
87 $rel_cols->{$1}{$2} = 1;
90 $my_cols->{$_} = {}; # important for ||='s below
95 # run through relationships, collect metadata
96 for my $rel (keys %$rel_cols) {
97 my $inf = $self->relationship_info ($rel);
100 is_single => ( $inf->{attrs}{accessor} && $inf->{attrs}{accessor} ne 'multi' ),
101 is_inner => ( ( $inf->{attrs}{join_type} || '' ) !~ /^left/i),
102 rsrc => $self->related_source($rel),
105 # FIME - need to use _resolve_cond here instead
106 my $cond = $inf->{cond};
113 ! defined first { $_ !~ /^foreign\./ } (keys %$cond)
115 ! defined first { $_ !~ /^self\./ } (values %$cond)
117 for my $f (keys %$cond) {
119 $_ =~ s/^ (?: foreign | self ) \.//x for ($f, $s);
120 $relinfo->{$rel}{fk_map}{$s} = $f;
125 # inject non-left fk-bridges from *INNER-JOINED* children (if any)
126 for my $rel (grep { $relinfo->{$_}{is_inner} } keys %$relinfo) {
127 my $ri = $relinfo->{$rel};
128 for (keys %{$ri->{fk_map}} ) {
129 # need to know source from *our* pov, hence $rel.col
130 $my_cols->{$_} ||= { via_fk => "$rel.$ri->{fk_map}{$_}" }
131 if defined $rel_cols->{$rel}{$ri->{fk_map}{$_}} # in fact selected
135 # if the parent is already defined, assume all of its related FKs are selected
136 # (even if they in fact are NOT in the select list). Keep a record of what we
137 # assumed, and if any such phantom-column becomes part of our own collapser,
138 # throw everything assumed-from-parent away and replace with the collapser of
139 # the parent (whatever it may be)
140 my $assumed_from_parent;
141 unless ($args->{_parent_info}{underdefined}) {
142 for my $col ( values %{$args->{_parent_info}{rel_condition} || {}} ) {
143 next if exists $my_cols->{$col};
144 $my_cols->{$col} = { via_collapse => $args->{_parent_info}{collapse_on_idcols} };
145 $assumed_from_parent->{columns}{$col}++;
149 # get colinfo for everything
151 my $ci = $self->columns_info;
152 $my_cols->{$_}{colinfo} = $ci->{$_} for keys %$my_cols;
157 # first try to reuse the parent's collapser (i.e. reuse collapser over 1:1)
158 # (makes for a leaner coderef later)
159 unless ($collapse_map->{-idcols_current_node}) {
160 $collapse_map->{-idcols_current_node} = $args->{_parent_info}{collapse_on_idcols}
161 if $args->{_parent_info}{collapser_reusable};
165 # Still dont know how to collapse - try to resolve based on our columns (plus already inserted FK bridges)
167 ! $collapse_map->{-idcols_current_node}
171 my $idset = $self->_identifying_column_set ({map { $_ => $my_cols->{$_}{colinfo} } keys %$my_cols})
173 # see if the resulting collapser relies on any implied columns,
174 # and fix stuff up if this is the case
175 my @reduced_set = grep { ! $assumed_from_parent->{columns}{$_} } @$idset;
177 $collapse_map->{-idcols_current_node} = [ __unique_numlist(
178 @{ $args->{_parent_info}{collapse_on_idcols}||[] },
183 @{$args->{_rel_chain}}[1 .. $#{$args->{_rel_chain}}],
184 ( $my_cols->{$_}{via_fk} || $_ ),
187 $common_args->{_as_fq_idx}->{$fqc};
194 # Stil don't know how to collapse - keep descending down 1:1 chains - if
195 # a related non-LEFT 1:1 is resolvable - its condition will collapse us
197 unless ($collapse_map->{-idcols_current_node}) {
200 for my $rel (keys %$relinfo) {
201 next unless ($relinfo->{$rel}{is_single} && $relinfo->{$rel}{is_inner});
203 if ( my $rel_collapse = $relinfo->{$rel}{rsrc}->_resolve_collapse ({
204 as => $rel_cols->{$rel},
205 _rel_chain => [ @{$args->{_rel_chain}}, $rel ],
206 _parent_info => { underdefined => 1 },
208 push @candidates, $rel_collapse->{-idcols_current_node};
212 # get the set with least amount of columns
213 # FIXME - maybe need to implement a data type order as well (i.e. prefer several ints
214 # to a single varchar)
216 ($collapse_map->{-idcols_current_node}) = sort { scalar @$a <=> scalar @$b } (@candidates);
220 # Stil don't know how to collapse, and we are the root node. Last ditch
221 # effort in case we are *NOT* premultiplied.
222 # Run through *each multi* all the way down, left or not, and all
223 # *left* singles (a single may become a multi underneath) . When everything
224 # gets back see if all the rels link to us definitively. If this is the
225 # case we are good - either one of them will define us, or if all are NULLs
226 # we know we are "unique" due to the "non-premultiplied" check
228 ! $collapse_map->{-idcols_current_node}
230 ! $args->{premultiplied}
232 $common_args->{_node_idx} == 1
234 my (@collapse_sets, $uncollapsible_chain);
236 for my $rel (keys %$relinfo) {
238 # we already looked at these higher up
239 next if ($relinfo->{$rel}{is_single} && $relinfo->{$rel}{is_inner});
241 if (my $clps = $relinfo->{$rel}{rsrc}->_resolve_collapse ({
242 as => $rel_cols->{$rel},
243 _rel_chain => [ @{$args->{_rel_chain}}, $rel ],
244 _parent_info => { underdefined => 1 },
247 # for singles use the idcols wholesale (either there or not)
248 if ($relinfo->{$rel}{is_single}) {
249 push @collapse_sets, $clps->{-idcols_current_node};
251 elsif (! $relinfo->{$rel}{fk_map}) {
252 $uncollapsible_chain = 1;
256 my $defined_cols_parent_side;
258 for my $fq_col ( grep { /^$rel\.[^\.]+$/ } keys %{$args->{as}} ) {
259 my ($col) = $fq_col =~ /([^\.]+)$/;
261 $defined_cols_parent_side->{$_} = $args->{as}{$fq_col} for grep
262 { $relinfo->{$rel}{fk_map}{$_} eq $col }
263 keys %{$relinfo->{$rel}{fk_map}}
267 if (my $set = $self->_identifying_column_set([ keys %$defined_cols_parent_side ]) ) {
268 push @collapse_sets, [ sort map { $defined_cols_parent_side->{$_} } @$set ];
271 $uncollapsible_chain = 1;
277 $uncollapsible_chain = 1;
282 unless ($uncollapsible_chain) {
283 # if we got here - we are good to go, but the construction is tricky
284 # since our children will want to include our collapse criteria - we
285 # don't give them anything (safe, since they are all collapsible on their own)
286 # in addition we record the individual collapse posibilities
287 # of all left children node collapsers, and merge them in the rowparser
289 $collapse_map->{-idcols_current_node} = [];
290 $collapse_map->{-root_node_idcol_variants} = [ sort {
291 (scalar @$a) <=> (scalar @$b) or max(@$a) <=> max(@$b)
296 # stop descending into children if we were called by a parent for first-pass
297 # and don't despair if nothing was found (there may be other parallel branches
299 if ($args->{_parent_info}{underdefined}) {
300 return $collapse_map->{-idcols_current_node} ? $collapse_map : undef
302 # nothing down the chain resolved - can't calculate a collapse-map
303 elsif (! $collapse_map->{-idcols_current_node}) {
304 $self->throw_exception ( sprintf
305 "Unable to calculate a definitive collapse column set for %s%s: fetch more unique non-nullable columns",
307 @{$args->{_rel_chain}} > 1
308 ? sprintf (' (last member of the %s chain)', join ' -> ', @{$args->{_rel_chain}} )
314 # If we got that far - we are collapsable - GREAT! Now go down all children
315 # a second time, and fill in the rest
317 $collapse_map->{-is_optional} = 1 if $args->{_parent_info}{is_optional};
318 $collapse_map->{-node_index} = $common_args->{_node_idx}++;
322 for my $rel (sort keys %$relinfo) {
324 $collapse_map->{$rel} = $relinfo->{$rel}{rsrc}->_resolve_collapse ({
325 as => { map { $_ => 1 } ( keys %{$rel_cols->{$rel}} ) },
326 _rel_chain => [ @{$args->{_rel_chain}}, $rel],
329 collapse_on_idcols => [ @{$collapse_map->{-idcols_current_node}} ],
331 rel_condition => $relinfo->{$rel}{fk_map},
333 is_optional => $collapse_map->{-is_optional},
335 # if this is a 1:1 our own collapser can be used as a collapse-map
336 # (regardless of left or not)
337 collapser_reusable => @{$collapse_map->{-idcols_current_node}} && $relinfo->{$rel}{is_single},
341 $collapse_map->{$rel}{-is_single} = 1 if $relinfo->{$rel}{is_single};
342 $collapse_map->{$rel}{-is_optional} ||= 1 unless $relinfo->{$rel}{is_inner};
343 push @id_sets, ( map { @$_ } (
344 $collapse_map->{$rel}{-idcols_current_node},
345 $collapse_map->{$rel}{-idcols_extra_from_children} || (),
350 my $cur_nodeid_hash = { map { $_ => 1 } @{$collapse_map->{-idcols_current_node}} };
351 $collapse_map->{-idcols_extra_from_children} = [ grep
352 { ! $cur_nodeid_hash->{$_} }
353 __unique_numlist( @id_sets )
357 return $collapse_map;
360 # Takes an arrayref of {as} dbic column aliases and the collapse and select
361 # attributes from the same $rs (the selector requirement is a temporary
362 # workaround... I hope), and returns a coderef capable of:
363 # my $me_pref_clps = $coderef->([$rs->cursor->next/all])
364 # Where the $me_pref_clps arrayref is the future argument to inflate_result()
366 # For an example of this coderef in action (and to see its guts) look at
367 # t/resultset/rowparser_internals.t
369 # This is a huge performance win, as we call the same code for every row
370 # returned from the db, thus avoiding repeated method lookups when traversing
373 # Also since the coderef is completely stateless (the returned structure is
374 # always fresh on every new invocation) this is a very good opportunity for
375 # memoization if further speed improvements are needed
377 # The way we construct this coderef is somewhat fugly, although the result is
378 # really worth it. The final coderef does not perform any kind of recursion -
379 # the entire nested structure constructor is rolled out into a single scope.
381 # In any case - the output of this thing is meticulously micro-tested, so
382 # any sort of adjustment/rewrite should be relatively easy (fsvo relatively)
385 my ($self, $args) = @_;
387 my $inflate_index = { map
388 { $args->{inflate_map}[$_] => $_ }
389 ( 0 .. $#{$args->{inflate_map}} )
394 # the non-collapsing assembler is easy
395 # FIXME SUBOPTIMAL there could be a yet faster way to do things here, but
396 # need to try an actual implementation and benchmark it:
398 # <timbunce_> First setup the nested data structure you want for each row
399 # Then call bind_col() to alias the row fields into the right place in
400 # the data structure, then to fetch the data do:
401 # push @rows, dclone($row_data_struct) while ($sth->fetchrow);
403 if (!$args->{collapse}) {
404 $parser_src = sprintf('$_ = %s for @{$_[0]}', __visit_infmap_simple(
408 # change the quoted placeholders to unquoted alias-references
409 $parser_src =~ s/ \' \xFF__VALPOS__(\d+)__\xFF \' /"\$_->[$1]"/gex;
412 # the collapsing parser is more complicated - it needs to keep a lot of state
415 my $collapse_map = $self->_resolve_collapse ({
416 premultiplied => $args->{premultiplied},
418 # only consider real columns (not functions) during collapse resolution
419 # this check shouldn't really be here, as fucktards are not supposed to
420 # alias random crap to existing column names anyway, but still - just in
422 # FIXME !!!! - this does not yet deal with unbalanced selectors correctly
423 # (it is now trivial as the attrs specify where things go out of sync
426 { ref $args->{selection}[$inflate_index->{$_}] ? () : ( $_ => $inflate_index->{$_} ) }
431 my @all_idcols = sort { $a <=> $b } map { @$_ } (
432 $collapse_map->{-idcols_current_node},
433 $collapse_map->{-idcols_extra_from_children} || (),
436 my ($top_node_id_path, $top_node_id_cacher, @path_variants);
437 if (scalar @{$collapse_map->{-idcols_current_node}}) {
438 $top_node_id_path = join ('', map
439 { "{'\xFF__IDVALPOS__${_}__\xFF'}" }
440 @{$collapse_map->{-idcols_current_node}}
443 elsif( my @variants = @{$collapse_map->{-root_node_idcol_variants}} ) {
448 push @path_variants, sprintf "(join qq(\xFF), '', %s, '')",
449 ( join ', ', map { "'\xFF__VALPOS__${_}__\xFF'" } @$_ )
452 push @path_parts, sprintf "( %s && %s)",
453 ( join ' && ', map { "( defined '\xFF__VALPOS__${_}__\xFF' )" } @$_ ),
458 $top_node_id_cacher = sprintf '$cur_row_ids[%d] = (%s);',
460 "\n" . join( "\n or\n", @path_parts, qq{"\0\$rows_pos\0"} );
461 $top_node_id_path = sprintf '{$cur_row_ids[%d]}', $all_idcols[-1] + 1;
464 $self->throw_exception('Unexpected collapse map contents');
467 my $rel_assemblers = __visit_infmap_collapse (
468 $inflate_index, { %$collapse_map, -custom_node_id => $top_node_id_path },
471 $parser_src = sprintf (<<'EOS', join(', ', @all_idcols), $top_node_id_path, $top_node_id_cacher||'', $rel_assemblers);
472 ### BEGIN LITERAL STRING EVAL
473 my ($rows_pos, $result_pos, $cur_row, @cur_row_ids, @collapse_idx, $is_new_res) = (0,0);
475 # this loop is a bit arcane - the rationale is that the passed in
476 # $_[0] will either have only one row (->next) or will have all
477 # rows already pulled in (->all and/or unordered). Given that the
478 # result can be rather large - we reuse the same already allocated
479 # array, since the collapsed prefetch is smaller by definition.
480 # At the end we cut the leftovers away and move on.
482 ( ( $rows_pos >= 0 and $_[0][$rows_pos++] ) or do { $rows_pos = -1; undef } )
484 ($_[1] and $_[1]->())
487 # due to left joins some of the ids may be NULL/undef, and
488 # won't play well when used as hash lookups
489 # we also need to differentiate NULLs on per-row/per-col basis
490 #(otherwise folding of optional 1:1s will be greatly confused
491 $cur_row_ids[$_] = defined $cur_row->[$_] ? $cur_row->[$_] : "\0NULL\xFF$rows_pos\xFF$_\0"
494 # maybe(!) cache the top node id calculation
497 $is_new_res = ! $collapse_idx[1]%2$s and (
498 $_[1] and $result_pos and (unshift @{$_[2]}, $cur_row) and last
503 $_[0][$result_pos++] = $collapse_idx[1]%2$s
507 splice @{$_[0]}, $result_pos; # truncate the passed in array for cases of collapsing ->all()
508 ### END LITERAL STRING EVAL
511 # !!! note - different var than the one above
512 # change the quoted placeholders to unquoted alias-references
513 $parser_src =~ s/ \' \xFF__VALPOS__(\d+)__\xFF \' /"\$cur_row->[$1]"/gex;
514 $parser_src =~ s/ \' \xFF__IDVALPOS__(\d+)__\xFF \' /"\$cur_row_ids[$1]"/gex;
520 # the simple non-collapsing nested structure recursor
521 sub __visit_infmap_simple {
522 my ($val_idx, $args) = @_;
526 for (keys %$val_idx) {
527 if ($_ =~ /^ ([^\.]+) \. (.+) /x) {
528 $rel_cols->{$1}{$2} = $val_idx->{$_};
531 $my_cols->{$_} = $val_idx->{$_};
535 for my $rel (sort keys %$rel_cols) {
538 #my $optional = $args->{is_optional};
539 #$optional ||= ($args->{rsrc}->relationship_info($rel)->{attrs}{join_type} || '') =~ /^left/i;
541 push @relperl, join ' => ', perlstring($rel), __visit_infmap_simple($rel_cols->{$rel}, {
544 #is_optional => $optional,
547 # FIXME SUBOPTIMAL DISABLEPRUNE - disabled to satisfy t/resultset/inflate_result_api.t
548 #if ($optional and my @branch_null_checks = map
549 # { "(! defined '\xFF__VALPOS__${_}__\xFF')" }
550 # sort { $a <=> $b } values %{$rel_cols->{$rel}}
552 # $relperl[-1] = sprintf ( '(%s) ? ( %s => [] ) : ( %s )',
553 # join (' && ', @branch_null_checks ),
560 my $me_struct = keys %$my_cols
561 ? __visit_dump({ map { $_ => "\xFF__VALPOS__$my_cols->{$_}__\xFF" } (keys %$my_cols) })
565 return sprintf '[%s]', join (',',
567 @relperl ? sprintf ('{ %s }', join (',', @relperl)) : (),
571 # the collapsing nested structure recursor
572 sub __visit_infmap_collapse {
574 my ($val_idx, $collapse_map, $parent_info) = @_;
578 for (keys %$val_idx) {
579 if ($_ =~ /^ ([^\.]+) \. (.+) /x) {
580 $rel_cols->{$1}{$2} = $val_idx->{$_};
583 $my_cols->{$_} = $val_idx->{$_};
587 my $sequenced_node_id = $collapse_map->{-custom_node_id} || join ('', map
588 { "{'\xFF__IDVALPOS__${_}__\xFF'}" }
589 @{$collapse_map->{-idcols_current_node}}
592 my $me_struct = keys %$my_cols
593 ? __visit_dump([{ map { $_ => "\xFF__VALPOS__$my_cols->{$_}__\xFF" } (keys %$my_cols) }])
596 my $node_idx_ref = sprintf '$collapse_idx[%d]%s', $collapse_map->{-node_index}, $sequenced_node_id;
598 my $parent_idx_ref = sprintf( '$collapse_idx[%d]%s[1]{%s}',
599 @{$parent_info}{qw/node_idx sequenced_node_id/},
600 perlstring($parent_info->{relname}),
604 if ($collapse_map->{-node_index} == 1) {
605 push @src, sprintf( '%s ||= %s;',
610 elsif ($collapse_map->{-is_single}) {
611 push @src, sprintf ( '%s ||= %s%s;',
614 $me_struct ? " ||= $me_struct" : '',
618 push @src, sprintf('push @{%s}, %s%s unless %s;',
621 $me_struct ? " ||= $me_struct" : '',
627 #my $known_defined = { %{ $parent_info->{known_defined} || {} } };
628 #$known_defined->{$_}++ for @{$collapse_map->{-idcols_current_node}};
629 for my $rel (sort keys %$rel_cols) {
631 # push @src, sprintf(
632 # '%s[1]{%s} ||= [];', $node_idx_ref, perlstring($rel)
633 # ) unless $collapse_map->{$rel}{-is_single};
635 push @src, __visit_infmap_collapse($rel_cols->{$rel}, $collapse_map->{$rel}, {
636 node_idx => $collapse_map->{-node_index},
637 sequenced_node_id => $sequenced_node_id,
640 #known_defined => $known_defined,
643 # FIXME SUBOPTIMAL DISABLEPRUNE - disabled to satisfy t/resultset/inflate_result_api.t
644 #if ($collapse_map->{$rel}{-is_optional} and my @null_checks = map
645 # { "(! defined '\xFF__IDVALPOS__${_}__\xFF')" }
646 # sort { $a <=> $b } grep
647 # { ! $known_defined->{$_} }
648 # @{$collapse_map->{$rel}{-idcols_current_node}}
650 # $src[-1] = sprintf( '(%s) or %s',
651 # join (' || ', @null_checks ),
660 # adding a dep on MoreUtils *just* for this is retarded
661 sub __unique_numlist {
662 sort { $a <=> $b } keys %{ {map { $_ => 1 } @_ }}
665 # keep our own DD object around so we don't have to fitz with quoting
668 # we actually will be producing functional perl code here,
669 # thus no second-guessing of what these globals might have
670 # been set to. DO NOT CHANGE!
671 ($dumper_obj ||= do {
672 require Data::Dumper;
673 Data::Dumper->new([])
683 ->Indent (0) # faster but harder to read, perhaps leave at 1 ?
684 })->Values ([$_[0]])->Dump;