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);
37 my $parser_src = sprintf('$_ = %s for @{$_[0]}', __visit_infmap_simple($_[0]) );
39 # change the quoted placeholders to unquoted alias-references
40 $parser_src =~ s/ \' \xFF__VALPOS__(\d+)__\xFF \' /"\$_->[$1]"/gex;
42 __wrap_in_strictured_scope($parser_src);
45 # the simple non-collapsing nested structure recursor
46 sub __visit_infmap_simple {
51 for (keys %{$args->{val_index}}) {
52 if ($_ =~ /^ ([^\.]+) \. (.+) /x) {
53 $rel_cols->{$1}{$2} = $args->{val_index}{$_};
56 $my_cols->{$_} = $args->{val_index}{$_};
61 for my $rel (sort keys %$rel_cols) {
63 my $rel_struct = __visit_infmap_simple({ %$args,
64 val_index => $rel_cols->{$rel},
69 my $branch_null_checks = join ' && ', map
70 { "( ! defined '\xFF__VALPOS__${_}__\xFF' )" }
71 sort { $a <=> $b } values %{$rel_cols->{$rel}}
74 if ($args->{prune_null_branches}) {
75 $rel_struct = sprintf ( '( (%s) ? undef : %s )',
81 $rel_struct = sprintf ( '( (%s) ? bless( (%s), %s ) : %s )',
84 perlstring($null_branch_class),
90 push @relperl, sprintf '( %s => %s )',
98 $me_struct = __result_struct_to_source($my_cols) if keys %$my_cols;
100 if ($args->{hri_style}) {
101 $me_struct =~ s/^ \s* \{ | \} \s* $//gx
104 return sprintf '{ %s }', join (', ', $me_struct||(), @relperl);
107 return sprintf '[%s]', join (',',
108 $me_struct || 'undef',
109 @relperl ? sprintf ('{ %s }', join (',', @relperl)) : (),
114 sub assemble_collapsing_parser {
117 my ($top_node_key, $top_node_key_assembler, $variant_idcols);
119 if (scalar @{$args->{collapse_map}{-identifying_columns}}) {
120 $top_node_key = join ('', map
121 { "{'\xFF__IDVALPOS__${_}__\xFF'}" }
122 @{$args->{collapse_map}{-identifying_columns}}
125 elsif( my @variants = @{$args->{collapse_map}{-identifying_columns_variants}} ) {
127 my @path_parts = map { sprintf
128 "( ( defined '\xFF__VALPOS__%d__\xFF' ) && (join qq(\xFF), '', %s, '') )",
129 $_->[0], # checking just first is enough - one ID defined, all defined
130 ( join ', ', map { ++$variant_idcols->{$_} and "'\xFF__IDVALPOS__${_}__\xFF'" } @$_ ),
133 my $virtual_column_idx = (scalar keys %{$args->{val_index}} ) + 1;
135 $top_node_key = "{'\xFF__IDVALPOS__${virtual_column_idx}__\xFF'}";
137 $top_node_key_assembler = sprintf "'\xFF__IDVALPOS__%d__\xFF' = (%s);",
139 "\n" . join( "\n or\n", @path_parts, qq{"\0\$rows_pos\0"} )
142 $args->{collapse_map} = {
143 %{$args->{collapse_map}},
144 -custom_node_key => $top_node_key,
148 die('Unexpected collapse map contents');
151 my ($data_assemblers, $stats) = __visit_infmap_collapse ($args);
153 # variants do not necessarily overlap with true idcols
154 my @row_ids = sort { $a <=> $b } keys %{ {
155 %{ $variant_idcols || {} },
156 %{ $stats->{idcols_seen} },
159 my $row_id_defs = sprintf "\@cur_row_ids{( %s )} = ( \n%s \n );",
160 join (', ', @row_ids ),
161 # in case we prune - we will never hit undefs/NULLs as pigeon-hole-criteria
162 ( $args->{prune_null_branches}
163 ? sprintf( '@{$cur_row_data}[( %s )]', join ', ', @row_ids )
165 my $quoted_null_val = qq( "\0NULL\xFF\${rows_pos}\xFF${_}\0" );
167 ? qq! ( \$cur_row_data->[$_] // $quoted_null_val ) !
168 : qq! ( defined(\$cur_row_data->[$_]) ? \$cur_row_data->[$_] : $quoted_null_val ) !
173 my $parser_src = sprintf (<<'EOS', $row_id_defs, $top_node_key_assembler||'', $top_node_key, join( "\n", @{$data_assemblers||[]} ) );
174 ### BEGIN LITERAL STRING EVAL
176 my ($result_pos, @collapse_idx, $cur_row_data, %%cur_row_ids );
178 # this loop is a bit arcane - the rationale is that the passed in
179 # $_[0] will either have only one row (->next) or will have all
180 # rows already pulled in (->all and/or unordered). Given that the
181 # result can be rather large - we reuse the same already allocated
182 # array, since the collapsed prefetch is smaller by definition.
183 # At the end we cut the leftovers away and move on.
184 while ($cur_row_data = (
185 ( $rows_pos >= 0 and $_[0][$rows_pos++] )
187 ( $_[1] and $rows_pos = -1 and $_[1]->() )
190 # the undef checks may or may not be there
191 # depending on whether we prune or not
193 # due to left joins some of the ids may be NULL/undef, and
194 # won't play well when used as hash lookups
195 # we also need to differentiate NULLs on per-row/per-col basis
196 # (otherwise folding of optional 1:1s will be greatly confused
199 # in the case of an underdefined root - calculate the virtual id (otherwise no code at all)
202 # if we were supplied a coderef - we are collapsing lazily (the set
203 # is ordered properly)
204 # as long as we have a result already and the next result is new we
205 # return the pre-read data and bail
206 $_[1] and $result_pos and ! $collapse_idx[0]%3$s and (unshift @{$_[2]}, $cur_row_data) and last;
213 $#{$_[0]} = $result_pos - 1; # truncate the passed in array to where we filled it with results
214 ### END LITERAL STRING EVAL
217 # !!! note - different var than the one above
218 # change the quoted placeholders to unquoted alias-references
219 $parser_src =~ s/ \' \xFF__VALPOS__(\d+)__\xFF \' /"\$cur_row_data->[$1]"/gex;
221 \' \xFF__IDVALPOS__(\d+)__\xFF \'
226 __wrap_in_strictured_scope($parser_src);
230 # the collapsing nested structure recursor
231 sub __visit_infmap_collapse {
232 my $args = {%{ shift() }};
234 my $cur_node_idx = ${ $args->{-node_idx_counter} ||= \do { my $x = 0} }++;
236 my ($my_cols, $rel_cols) = {};
237 for ( keys %{$args->{val_index}} ) {
238 if ($_ =~ /^ ([^\.]+) \. (.+) /x) {
239 $rel_cols->{$1}{$2} = $args->{val_index}{$_};
242 $my_cols->{$_} = $args->{val_index}{$_};
247 if ($args->{hri_style}) {
248 delete $my_cols->{$_} for grep { $rel_cols->{$_} } keys %$my_cols;
252 $me_struct = __result_struct_to_source($my_cols) if keys %$my_cols;
254 $me_struct = sprintf( '[ %s ]', $me_struct||'' )
255 unless $args->{hri_style};
258 my $node_key = $args->{collapse_map}->{-custom_node_key} || join ('', map
259 { "{'\xFF__IDVALPOS__${_}__\xFF'}" }
260 @{$args->{collapse_map}->{-identifying_columns}}
262 my $node_idx_slot = sprintf '$collapse_idx[%d]%s', $cur_node_idx, $node_key;
267 if ($cur_node_idx == 0) {
268 push @src, sprintf( '%s %s $_[0][$result_pos++] = %s;',
270 (HAS_DOR ? '//=' : '||='),
275 my $parent_attach_slot = sprintf( '$collapse_idx[%d]%s%s{%s}',
276 @{$args}{qw/-parent_node_idx -parent_node_key/},
277 $args->{hri_style} ? '' : '[1]',
278 perlstring($args->{-node_rel_name}),
281 if ($args->{collapse_map}->{-is_single}) {
282 push @src, sprintf ( '%s %s %s%s;',
284 (HAS_DOR ? '//=' : '||='),
286 $me_struct ? " = $me_struct" : '',
290 push @src, sprintf('(! %s) and push @{%s}, %s%s;',
294 $me_struct ? " = $me_struct" : '',
299 my $known_present_ids = { map { $_ => 1 } @{$args->{collapse_map}{-identifying_columns}} };
300 my ($stats, $rel_src);
302 for my $rel (sort keys %$rel_cols) {
304 my $relinfo = $args->{collapse_map}{$rel};
306 ($rel_src, $stats->{$rel}) = __visit_infmap_collapse({ %$args,
307 val_index => $rel_cols->{$rel},
308 collapse_map => $relinfo,
309 -parent_node_idx => $cur_node_idx,
310 -parent_node_key => $node_key,
311 -node_rel_name => $rel,
314 my $rel_src_pos = $#src + 1;
315 push @src, @$rel_src;
318 $relinfo->{-is_optional}
320 defined ( my $first_distinct_child_idcol = first
321 { ! $known_present_ids->{$_} }
322 @{$relinfo->{-identifying_columns}}
326 if ($args->{prune_null_branches}) {
328 # start of wrap of the entire chain in a conditional
329 splice @src, $rel_src_pos, 0, sprintf "( ! defined %s )\n ? %s%s{%s} = %s\n : do {",
330 "'\xFF__VALPOS__${first_distinct_child_idcol}__\xFF'",
332 $args->{hri_style} ? '' : '[1]',
334 ($args->{hri_style} && $relinfo->{-is_single}) ? 'undef' : '[]'
342 splice @src, $rel_src_pos + 1, 0, sprintf ( '(defined %s) or bless (%s[1]{%s}, %s);',
343 "'\xFF__VALPOS__${first_distinct_child_idcol}__\xFF'",
346 perlstring($null_branch_class),
356 ( map { %{ $_->{idcols_seen} } } values %$stats ),
357 ( map { $_ => 1 } @{$args->{collapse_map}->{-identifying_columns}} ),
363 sub __result_struct_to_source {
364 sprintf( '{ %s }', join (', ', map
365 { sprintf "%s => '\xFF__VALPOS__%d__\xFF'", perlstring($_), $_[0]{$_} }