1 package # hide from the pauses
2 DBIx::Class::ResultSource::RowParser::Util;
7 use List::Util 'first';
8 use DBIx::Class::_Util 'perlstring';
10 use constant HAS_DOR => ( $] < 5.010 ? 0 : 1 );
14 assemble_simple_parser
15 assemble_collapsing_parser
18 # working title - we are hoping to extract this eventually...
19 our $null_branch_class = 'DBIx::ResultParser::RelatedNullBranch';
21 sub __wrap_in_strictured_scope {
22 " { use strict; use warnings; use warnings FATAL => 'uninitialized';\n$_[0]\n }"
25 sub assemble_simple_parser {
28 # the non-collapsing assembler is easy
29 # FIXME SUBOPTIMAL there could be a yet faster way to do things here, but
30 # need to try an actual implementation and benchmark it:
32 # <timbunce_> First setup the nested data structure you want for each row
33 # Then call bind_col() to alias the row fields into the right place in
34 # the data structure, then to fetch the data do:
35 # push @rows, dclone($row_data_struct) while ($sth->fetchrow);
38 __wrap_in_strictured_scope( sprintf
39 '$_ = %s for @{$_[0]}',
40 __visit_infmap_simple( $_[0] )
44 # the simple non-collapsing nested structure recursor
45 sub __visit_infmap_simple {
50 for (keys %{$args->{val_index}}) {
51 if ($_ =~ /^ ([^\.]+) \. (.+) /x) {
52 $rel_cols->{$1}{$2} = $args->{val_index}{$_};
55 $my_cols->{$_} = $args->{val_index}{$_};
60 for my $rel (sort keys %$rel_cols) {
62 my $rel_struct = __visit_infmap_simple({ %$args,
63 val_index => $rel_cols->{$rel},
68 my $branch_null_checks = join ' && ', map
69 { "( ! defined \$_->[$_] )" }
70 sort { $a <=> $b } values %{$rel_cols->{$rel}}
73 if ($args->{prune_null_branches}) {
74 $rel_struct = sprintf ( '( (%s) ? undef : %s )',
80 $rel_struct = sprintf ( '( (%s) ? bless( (%s), %s ) : %s )',
83 perlstring($null_branch_class),
89 push @relperl, sprintf '( %s => %s )',
97 $me_struct = __result_struct_to_source($my_cols) if keys %$my_cols;
99 if ($args->{hri_style}) {
100 $me_struct =~ s/^ \s* \{ | \} \s* $//gx
103 return sprintf '{ %s }', join (', ', $me_struct||(), @relperl);
106 return sprintf '[%s]', join (',',
107 $me_struct || 'undef',
108 @relperl ? sprintf ('{ %s }', join (',', @relperl)) : (),
113 sub assemble_collapsing_parser {
116 my ($top_node_key, $top_node_key_assembler, $variant_idcols);
118 if (scalar @{$args->{collapse_map}{-identifying_columns}}) {
119 $top_node_key = join ('', map
120 { "{ \$cur_row_ids{$_} }" }
121 @{$args->{collapse_map}{-identifying_columns}}
124 elsif( my @variants = @{$args->{collapse_map}{-identifying_columns_variants}} ) {
126 my @path_parts = map { sprintf
127 "( ( defined \$cur_row_data->[%d] ) && (join qq(\xFF), '', %s, '') )",
128 $_->[0], # checking just first is enough - one ID defined, all defined
129 ( join ', ', map { ++$variant_idcols->{$_} and " \$cur_row_ids{$_} " } @$_ ),
132 my $virtual_column_idx = (scalar keys %{$args->{val_index}} ) + 1;
134 $top_node_key = "{ \$cur_row_ids{$virtual_column_idx} }";
136 $top_node_key_assembler = sprintf "( \$cur_row_ids{%d} = (%s) ),",
138 "\n" . join( "\n or\n", @path_parts, qq{"\0\$rows_pos\0"} )
141 $args->{collapse_map} = {
142 %{$args->{collapse_map}},
143 -custom_node_key => $top_node_key,
147 die('Unexpected collapse map contents');
150 my ($data_assemblers, $stats) = __visit_infmap_collapse ($args);
152 # variants do not necessarily overlap with true idcols
153 my @row_ids = sort { $a <=> $b } keys %{ {
154 %{ $variant_idcols || {} },
155 %{ $stats->{idcols_seen} },
158 my $row_id_defs = sprintf "( \@cur_row_ids{( %s )} = (\n%s\n ) ),",
159 join (', ', @row_ids ),
160 # in case we prune - we will never hit undefs/NULLs as pigeon-hole-criteria
161 ( $args->{prune_null_branches}
162 ? sprintf( '@{$cur_row_data}[( %s )]', join ', ', @row_ids )
164 my $quoted_null_val = qq("\0NULL\xFF\${rows_pos}\xFF${_}\0");
166 ? qq!( \$cur_row_data->[$_] // $quoted_null_val )!
167 : qq!( defined(\$cur_row_data->[$_]) ? \$cur_row_data->[$_] : $quoted_null_val )!
172 my $parser_src = sprintf (<<'EOS', $row_id_defs, $top_node_key_assembler||'', $top_node_key, join( "\n", @{$data_assemblers||[]} ) );
173 ### BEGIN LITERAL STRING EVAL
175 my ($result_pos, @collapse_idx, $cur_row_data, %%cur_row_ids );
177 # this loop is a bit arcane - the rationale is that the passed in
178 # $_[0] will either have only one row (->next) or will have all
179 # rows already pulled in (->all and/or unordered). Given that the
180 # result can be rather large - we reuse the same already allocated
181 # array, since the collapsed prefetch is smaller by definition.
182 # At the end we cut the leftovers away and move on.
183 while ($cur_row_data = (
190 # It may be tempting to drop the -1 and undef $rows_pos instead
191 # thus saving the >= comparison above as well
192 # However NULL-handlers and underdefined root markers both use
193 # $rows_pos as a last-resort-uniqueness marker (it either is
194 # monotonically increasing while we parse ->all, or is set at
195 # a steady -1 when we are dealing with a single root node). For
196 # the time being the complication of changing all callsites seems
197 # overkill, for what is going to be a very modest saving of ops
198 ( ($rows_pos = -1), undef )
202 ( $_[1] and $_[1]->() )
205 # the undef checks may or may not be there
206 # depending on whether we prune or not
208 # due to left joins some of the ids may be NULL/undef, and
209 # won't play well when used as hash lookups
210 # we also need to differentiate NULLs on per-row/per-col basis
211 # (otherwise folding of optional 1:1s will be greatly confused
214 # in the case of an underdefined root - calculate the virtual id (otherwise no code at all)
217 # if we were supplied a coderef - we are collapsing lazily (the set
218 # is ordered properly)
219 # as long as we have a result already and the next result is new we
220 # return the pre-read data and bail
221 ( $_[1] and $result_pos and ! $collapse_idx[0]%3$s and (unshift @{$_[2]}, $cur_row_data) and last ),
228 $#{$_[0]} = $result_pos - 1; # truncate the passed in array to where we filled it with results
229 ### END LITERAL STRING EVAL
232 __wrap_in_strictured_scope($parser_src);
236 # the collapsing nested structure recursor
237 sub __visit_infmap_collapse {
238 my $args = {%{ shift() }};
240 my $cur_node_idx = ${ $args->{-node_idx_counter} ||= \do { my $x = 0} }++;
242 my ($my_cols, $rel_cols) = {};
243 for ( keys %{$args->{val_index}} ) {
244 if ($_ =~ /^ ([^\.]+) \. (.+) /x) {
245 $rel_cols->{$1}{$2} = $args->{val_index}{$_};
248 $my_cols->{$_} = $args->{val_index}{$_};
253 if ($args->{hri_style}) {
254 delete $my_cols->{$_} for grep { $rel_cols->{$_} } keys %$my_cols;
258 $me_struct = __result_struct_to_source($my_cols, 1) if keys %$my_cols;
260 $me_struct = sprintf( '[ %s ]', $me_struct||'' )
261 unless $args->{hri_style};
264 my $node_key = $args->{collapse_map}->{-custom_node_key} || join ('', map
265 { "{ \$cur_row_ids{$_} }" }
266 @{$args->{collapse_map}->{-identifying_columns}}
268 my $node_idx_slot = sprintf '$collapse_idx[%d]%s', $cur_node_idx, $node_key;
273 if ($cur_node_idx == 0) {
274 push @src, sprintf( '( %s %s $_[0][$result_pos++] = %s ),',
276 (HAS_DOR ? '//=' : '||='),
281 my $parent_attach_slot = sprintf( '$collapse_idx[%d]%s%s{%s}',
282 @{$args}{qw/-parent_node_idx -parent_node_key/},
283 $args->{hri_style} ? '' : '[1]',
284 perlstring($args->{-node_rel_name}),
287 if ($args->{collapse_map}->{-is_single}) {
288 push @src, sprintf ( '( %s %s %s%s ),',
290 (HAS_DOR ? '//=' : '||='),
292 $me_struct ? " = $me_struct" : '',
296 push @src, sprintf('( (! %s) and push @{%s}, %s%s ),',
300 $me_struct ? " = $me_struct" : '',
305 my $known_present_ids = { map { $_ => 1 } @{$args->{collapse_map}{-identifying_columns}} };
306 my ($stats, $rel_src);
308 for my $rel (sort keys %$rel_cols) {
310 my $relinfo = $args->{collapse_map}{$rel};
312 ($rel_src, $stats->{$rel}) = __visit_infmap_collapse({ %$args,
313 val_index => $rel_cols->{$rel},
314 collapse_map => $relinfo,
315 -parent_node_idx => $cur_node_idx,
316 -parent_node_key => $node_key,
317 -node_rel_name => $rel,
320 my $rel_src_pos = $#src + 1;
321 push @src, @$rel_src;
324 $relinfo->{-is_optional}
326 defined ( my $first_distinct_child_idcol = first
327 { ! $known_present_ids->{$_} }
328 @{$relinfo->{-identifying_columns}}
332 if ($args->{prune_null_branches}) {
334 # start of wrap of the entire chain in a conditional
335 splice @src, $rel_src_pos, 0, sprintf "( ( ! defined %s )\n ? %s%s{%s} = %s\n : do {",
336 "\$cur_row_data->[$first_distinct_child_idcol]",
338 $args->{hri_style} ? '' : '[1]',
340 ($args->{hri_style} && $relinfo->{-is_single}) ? 'undef' : '[]'
348 splice @src, $rel_src_pos + 1, 0, sprintf ( '( (defined %s) or bless (%s[1]{%s}, %s) ),',
349 "\$cur_row_data->[$first_distinct_child_idcol]",
352 perlstring($null_branch_class),
362 ( map { %{ $_->{idcols_seen} } } values %$stats ),
363 ( map { $_ => 1 } @{$args->{collapse_map}->{-identifying_columns}} ),
369 sub __result_struct_to_source {
370 my ($data, $is_collapsing) = @_;
374 sprintf ( "%s => %s",
377 ? "\$cur_row_data->[$data->{$_}]"
378 : "\$_->[ $data->{$_} ]"