1 package # hide from the pauses
2 DBIx::Class::ResultSource::RowParser::Util;
7 use DBIx::Class::_Util qw( perlstring dump_value );
9 use constant HAS_DOR => ( "$]" < 5.010 ? 0 : 1 );
13 assemble_simple_parser
14 assemble_collapsing_parser
17 # working title - we are hoping to extract this eventually...
18 our $null_branch_class = 'DBIx::ResultParser::RelatedNullBranch';
20 sub __wrap_in_strictured_scope {
21 " { use strict; use warnings; use warnings FATAL => 'uninitialized';\n$_[0]\n }"
24 sub assemble_simple_parser {
27 # the non-collapsing assembler is easy
28 # FIXME SUBOPTIMAL there could be a yet faster way to do things here, but
29 # need to try an actual implementation and benchmark it:
31 # <timbunce_> First setup the nested data structure you want for each row
32 # Then call bind_col() to alias the row fields into the right place in
33 # the data structure, then to fetch the data do:
34 # push @rows, dclone($row_data_struct) while ($sth->fetchrow);
37 __wrap_in_strictured_scope( sprintf
38 '$_ = %s for @{$_[0]}',
39 __visit_infmap_simple( $_[0] )
43 # the simple non-collapsing nested structure recursor
44 sub __visit_infmap_simple {
49 for (keys %{$args->{val_index}}) {
50 if ($_ =~ /^ ([^\.]+) \. (.+) /x) {
51 $rel_cols->{$1}{$2} = $args->{val_index}{$_};
54 $my_cols->{$_} = $args->{val_index}{$_};
59 for my $rel (sort keys %$rel_cols) {
61 my $rel_struct = __visit_infmap_simple({ %$args,
62 val_index => $rel_cols->{$rel},
67 my $branch_null_checks = join ' && ', map
68 { "( ! defined \$_->[$_] )" }
69 sort { $a <=> $b } values %{$rel_cols->{$rel}}
72 if ($args->{prune_null_branches}) {
73 $rel_struct = sprintf ( '( (%s) ? undef : %s )',
79 $rel_struct = sprintf ( '( (%s) ? bless( (%s), %s ) : %s )',
82 perlstring($null_branch_class),
88 push @relperl, sprintf '( %s => %s )',
96 $me_struct = __result_struct_to_source($my_cols) if keys %$my_cols;
98 if ($args->{hri_style}) {
99 $me_struct =~ s/^ \s* \{ | \} \s* $//gx
102 return sprintf '{ %s }', join (', ', $me_struct||(), @relperl);
105 return sprintf '[%s]', join (',',
106 $me_struct || 'undef',
107 @relperl ? sprintf ('{ %s }', join (',', @relperl)) : (),
112 sub assemble_collapsing_parser {
115 my ($top_node_key, $top_node_key_assembler, $variant_idcols);
117 if (scalar @{$args->{collapse_map}{-identifying_columns}}) {
118 $top_node_key = join ('', map
119 { "{ \$cur_row_ids{$_} }" }
120 @{$args->{collapse_map}{-identifying_columns}}
123 elsif( my @variants = @{$args->{collapse_map}{-identifying_columns_variants}} ) {
125 my @path_parts = map { sprintf
126 "( ( defined \$cur_row_data->[%d] ) && (join qq(\xFF), '', %s, '') )",
127 $_->[0], # checking just first is enough - one ID defined, all defined
128 ( join ', ', map { $variant_idcols->{$_} = 1; " \$cur_row_ids{$_} " } @$_ ),
131 my $virtual_column_idx = (scalar keys %{$args->{val_index}} ) + 1;
133 $top_node_key = "{ \$cur_row_ids{$virtual_column_idx} }";
135 $top_node_key_assembler = sprintf "( \$cur_row_ids{%d} = (%s) ),",
137 "\n" . join( "\n or\n", @path_parts, qq{"\0\$rows_pos\0"} )
140 $args->{collapse_map} = {
141 %{$args->{collapse_map}},
142 -custom_node_key => $top_node_key,
146 DBIx::Class::Exception->throw(
147 'Unexpected collapse map contents: ' . dump_value $args->{collapse_map},
152 my ($data_assemblers, $stats) = __visit_infmap_collapse ($args);
154 # variants do not necessarily overlap with true idcols
155 my @row_ids = sort { $a <=> $b } keys %{ {
156 %{ $variant_idcols || {} },
157 %{ $stats->{idcols_seen} },
160 my $row_id_defs = sprintf "( \@cur_row_ids{( %s )} = (\n%s\n ) ),",
161 join (', ', @row_ids ),
162 # in case we prune - we will never hit undefs/NULLs as pigeon-hole-criteria
163 ( $args->{prune_null_branches}
164 ? sprintf( '@{$cur_row_data}[( %s )]', join ', ', @row_ids )
166 my $quoted_null_val = qq("\0NULL\xFF\${rows_pos}\xFF${_}\0");
168 ? qq!( \$cur_row_data->[$_] // $quoted_null_val )!
169 : qq!( defined(\$cur_row_data->[$_]) ? \$cur_row_data->[$_] : $quoted_null_val )!
174 my $parser_src = sprintf (<<'EOS', $row_id_defs, $top_node_key_assembler||'', $top_node_key, join( "\n", @$data_assemblers ) );
175 ### BEGIN LITERAL STRING EVAL
177 my ($result_pos, @collapse_idx, $cur_row_data, %%cur_row_ids );
179 # this loop is a bit arcane - the rationale is that the passed in
180 # $_[0] will either have only one row (->next) or will have all
181 # rows already pulled in (->all and/or unordered). Given that the
182 # result can be rather large - we reuse the same already allocated
183 # array, since the collapsed prefetch is smaller by definition.
184 # At the end we cut the leftovers away and move on.
185 while ($cur_row_data = (
192 # It may be tempting to drop the -1 and undef $rows_pos instead
193 # thus saving the >= comparison above as well
194 # However NULL-handlers and underdefined root markers both use
195 # $rows_pos as a last-resort-uniqueness marker (it either is
196 # monotonically increasing while we parse ->all, or is set at
197 # a steady -1 when we are dealing with a single root node). For
198 # the time being the complication of changing all callsites seems
199 # overkill, for what is going to be a very modest saving of ops
200 ( ($rows_pos = -1), undef )
204 ( $_[1] and $_[1]->() )
207 # the undef checks may or may not be there
208 # depending on whether we prune or not
210 # due to left joins some of the ids may be NULL/undef, and
211 # won't play well when used as hash lookups
212 # we also need to differentiate NULLs on per-row/per-col basis
213 # (otherwise folding of optional 1:1s will be greatly confused
216 # in the case of an underdefined root - calculate the virtual id (otherwise no code at all)
219 # if we were supplied a coderef - we are collapsing lazily (the set
220 # is ordered properly)
221 # as long as we have a result already and the next result is new we
222 # return the pre-read data and bail
223 ( $_[1] and $result_pos and ! $collapse_idx[0]%3$s and (unshift @{$_[2]}, $cur_row_data) and last ),
230 $#{$_[0]} = $result_pos - 1; # truncate the passed in array to where we filled it with results
231 ### END LITERAL STRING EVAL
234 __wrap_in_strictured_scope($parser_src);
238 # the collapsing nested structure recursor
239 sub __visit_infmap_collapse {
240 my $args = {%{ shift() }};
242 my $cur_node_idx = ${ $args->{-node_idx_counter} ||= \do { my $x = 0} }++;
244 my ($my_cols, $rel_cols) = {};
245 for ( keys %{$args->{val_index}} ) {
246 if ($_ =~ /^ ([^\.]+) \. (.+) /x) {
247 $rel_cols->{$1}{$2} = $args->{val_index}{$_};
250 $my_cols->{$_} = $args->{val_index}{$_};
255 if ($args->{hri_style}) {
256 delete $my_cols->{$_} for grep { $rel_cols->{$_} } keys %$my_cols;
260 $me_struct = __result_struct_to_source($my_cols, 1) if keys %$my_cols;
262 $me_struct = sprintf( '[ %s ]', $me_struct||'' )
263 unless $args->{hri_style};
266 my $node_key = $args->{collapse_map}->{-custom_node_key} || join ('', map
267 { "{ \$cur_row_ids{$_} }" }
268 @{$args->{collapse_map}->{-identifying_columns}}
270 my $node_idx_slot = sprintf '$collapse_idx[%d]%s', $cur_node_idx, $node_key;
275 if ($cur_node_idx == 0) {
276 push @src, sprintf( '( %s %s $_[0][$result_pos++] = %s ),',
278 (HAS_DOR ? '//=' : '||='),
283 my $parent_attach_slot = sprintf( '$collapse_idx[%d]%s%s{%s}',
284 @{$args}{qw/-parent_node_idx -parent_node_key/},
285 $args->{hri_style} ? '' : '[1]',
286 perlstring($args->{-node_rel_name}),
289 if ($args->{collapse_map}->{-is_single}) {
290 push @src, sprintf ( '( %s %s %s = %s ),',
292 (HAS_DOR ? '//=' : '||='),
298 push @src, sprintf('( (! %s) and push @{%s}, %s = %s ),',
307 my $known_present_ids = { map { $_ => 1 } @{$args->{collapse_map}{-identifying_columns}} };
308 my ($stats, $rel_src);
310 for my $rel (sort keys %$rel_cols) {
312 my $relinfo = $args->{collapse_map}{$rel};
314 ($rel_src, $stats->{$rel}) = __visit_infmap_collapse({ %$args,
315 val_index => $rel_cols->{$rel},
316 collapse_map => $relinfo,
317 -parent_node_idx => $cur_node_idx,
318 -parent_node_key => $node_key,
319 -node_rel_name => $rel,
322 my $rel_src_pos = $#src + 1;
323 push @src, @$rel_src;
326 $relinfo->{-is_optional}
329 my ($first_distinct_child_idcol) = grep
330 { ! $known_present_ids->{$_} }
331 @{$relinfo->{-identifying_columns}}
334 DBIx::Class::Exception->throw(
335 "An optional node *without* a distinct identifying set shouldn't be possible: " . dump_value $args->{collapse_map},
337 ) unless defined $first_distinct_child_idcol;
339 if ($args->{prune_null_branches}) {
341 # start of wrap of the entire chain in a conditional
342 splice @src, $rel_src_pos, 0, sprintf "( ( ! defined %s )\n ? %s%s{%s} = %s\n : do {",
343 "\$cur_row_data->[$first_distinct_child_idcol]",
345 $args->{hri_style} ? '' : '[1]',
347 ($args->{hri_style} && $relinfo->{-is_single}) ? 'undef' : '[]'
355 splice @src, $rel_src_pos + 1, 0, sprintf ( '( (defined %s) or bless (%s[1]{%s}, %s) ),',
356 "\$cur_row_data->[$first_distinct_child_idcol]",
359 perlstring($null_branch_class),
369 ( map { %{ $_->{idcols_seen} } } values %$stats ),
370 ( map { $_ => 1 } @{$args->{collapse_map}->{-identifying_columns}} ),
376 sub __result_struct_to_source {
377 my ($data, $is_collapsing) = @_;
381 sprintf ( "%s => %s",
384 ? "\$cur_row_data->[$data->{$_}]"
385 : "\$_->[ $data->{$_} ]"