Commit | Line | Data |
4e9fc3f3 |
1 | package # hide from the pauses |
2 | DBIx::Class::ResultSource::RowParser; |
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3 | |
4 | use strict; |
5 | use warnings; |
6 | |
9f98c4b2 |
7 | use base 'DBIx::Class'; |
8 | |
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9 | use Try::Tiny; |
fcf32d04 |
10 | use List::Util qw(first max); |
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11 | |
9f98c4b2 |
12 | use DBIx::Class::ResultSource::RowParser::Util qw( |
13 | assemble_simple_parser |
14 | assemble_collapsing_parser |
15 | ); |
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16 | |
47dba3e3 |
17 | use DBIx::Class::Carp; |
18 | |
9f98c4b2 |
19 | use namespace::clean; |
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20 | |
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21 | # Accepts a prefetch map (one or more relationships for the current source), |
22 | # returns a set of select/as pairs for each of those relationships. Columns |
23 | # are fully qualified inflation_slot names |
24 | sub _resolve_selection_from_prefetch { |
25 | my ($self, $pre, $alias_map, $pref_path) = @_; |
26 | |
27 | # internal recursion marker |
76031e14 |
28 | $pref_path ||= []; |
29 | |
30 | if (not defined $pre or not length $pre) { |
31 | return (); |
32 | } |
33 | elsif( ref $pre eq 'ARRAY' ) { |
47dba3e3 |
34 | map { $self->_resolve_selection_from_prefetch( $_, $alias_map, [ @$pref_path ] ) } |
35 | @$pre; |
76031e14 |
36 | } |
37 | elsif( ref $pre eq 'HASH' ) { |
76031e14 |
38 | map { |
47dba3e3 |
39 | $self->_resolve_selection_from_prefetch($_, $alias_map, [ @$pref_path ] ), |
40 | $self->related_source($_)->_resolve_selection_from_prefetch( |
41 | $pre->{$_}, $alias_map, [ @$pref_path, $_] ) |
76031e14 |
42 | } keys %$pre; |
76031e14 |
43 | } |
44 | elsif( ref $pre ) { |
45 | $self->throw_exception( |
46 | "don't know how to resolve prefetch reftype ".ref($pre)); |
47 | } |
48 | else { |
49 | my $p = $alias_map; |
47dba3e3 |
50 | $p = $p->{$_} for @$pref_path, $pre; |
76031e14 |
51 | |
52 | $self->throw_exception ( |
53 | "Unable to resolve prefetch '$pre' - join alias map does not contain an entry for path: " |
54 | . join (' -> ', @$pref_path, $pre) |
55 | ) if (ref $p->{-join_aliases} ne 'ARRAY' or not @{$p->{-join_aliases}} ); |
56 | |
47dba3e3 |
57 | # this shift() is critical - it is what allows prefetch => [ (foo) x 2 ] to work |
58 | my $src_alias = shift @{$p->{-join_aliases}}; |
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59 | |
47dba3e3 |
60 | # ordered [select => as] pairs |
61 | map { [ |
62 | "${src_alias}.$_" => join ( '.', |
63 | @$pref_path, |
64 | $pre, |
65 | $_, |
66 | ) |
67 | ] } $self->related_source($pre)->columns; |
68 | } |
69 | } |
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70 | |
47dba3e3 |
71 | sub _resolve_prefetch { |
72 | carp_unique( |
73 | 'There is no good reason to call this internal deprecated method - ' |
74 | . 'please open a ticket detailing your usage, so that a better plan can ' |
75 | . 'be devised for your case. In either case _resolve_prefetch() is ' |
76 | . 'deprecated in favor of _resolve_selection_from_prefetch(), which has ' |
77 | . 'a greatly simplified arglist.' |
78 | ); |
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79 | |
47dba3e3 |
80 | $_[0]->_resolve_selection_from_prefetch( $_[1], $_[3] ); |
76031e14 |
81 | } |
82 | |
47dba3e3 |
83 | |
9f98c4b2 |
84 | # Takes an arrayref of {as} dbic column aliases and the collapse and select |
85 | # attributes from the same $rs (the selector requirement is a temporary |
86 | # workaround... I hope), and returns a coderef capable of: |
87 | # my $me_pref_clps = $coderef->([$rs->cursor->next/all]) |
88 | # Where the $me_pref_clps arrayref is the future argument to inflate_result() |
89 | # |
90 | # For an example of this coderef in action (and to see its guts) look at |
91 | # t/resultset/rowparser_internals.t |
92 | # |
93 | # This is a huge performance win, as we call the same code for every row |
94 | # returned from the db, thus avoiding repeated method lookups when traversing |
95 | # relationships |
96 | # |
97 | # Also since the coderef is completely stateless (the returned structure is |
98 | # always fresh on every new invocation) this is a very good opportunity for |
99 | # memoization if further speed improvements are needed |
100 | # |
101 | # The way we construct this coderef is somewhat fugly, although the result is |
102 | # really worth it. The final coderef does not perform any kind of recursion - |
103 | # the entire nested structure constructor is rolled out into a single scope. |
104 | # |
105 | # In any case - the output of this thing is meticulously micro-tested, so |
106 | # any sort of adjustment/rewrite should be relatively easy (fsvo relatively) |
107 | # |
108 | sub _mk_row_parser { |
4a0eed52 |
109 | # $args and $attrs are separated to delineate what is core collapser stuff and |
5b309063 |
110 | # what is dbic $rs specific |
111 | my ($self, $args, $attrs) = @_; |
9f98c4b2 |
112 | |
79adc44f |
113 | die "HRI without pruning makes zero sense" |
114 | if ( $args->{hri_style} && ! $args->{prune_null_branches} ); |
115 | |
116 | my %common = ( |
117 | hri_style => $args->{hri_style}, |
118 | prune_null_branches => $args->{prune_null_branches}, |
119 | val_index => { map |
120 | { $args->{inflate_map}[$_] => $_ } |
121 | ( 0 .. $#{$args->{inflate_map}} ) |
122 | }, |
123 | ); |
124 | |
02a73c96 |
125 | my $check_null_columns; |
126 | |
127 | my $src = (! $args->{collapse} ) ? assemble_simple_parser(\%common) : do { |
128 | my $collapse_map = $self->_resolve_collapse ({ |
129 | # FIXME |
130 | # only consider real columns (not functions) during collapse resolution |
131 | # this check shouldn't really be here, as fucktards are not supposed to |
132 | # alias random crap to existing column names anyway, but still - just in |
133 | # case |
134 | # FIXME !!!! - this does not yet deal with unbalanced selectors correctly |
135 | # (it is now trivial as the attrs specify where things go out of sync |
136 | # needs MOAR tests) |
137 | as => { map |
138 | { ref $attrs->{select}[$common{val_index}{$_}] ? () : ( $_ => $common{val_index}{$_} ) } |
139 | keys %{$common{val_index}} |
140 | }, |
141 | premultiplied => $args->{premultiplied}, |
142 | }); |
143 | |
144 | $check_null_columns = $collapse_map->{-identifying_columns} |
145 | if @{$collapse_map->{-identifying_columns}}; |
146 | |
147 | assemble_collapsing_parser({ |
79adc44f |
148 | %common, |
02a73c96 |
149 | collapse_map => $collapse_map, |
150 | }); |
151 | }; |
152 | |
2fdeef65 |
153 | utf8::upgrade($src) |
154 | if DBIx::Class::_ENV_::STRESSTEST_UTF8_UPGRADE_GENERATED_COLLAPSER_SOURCE; |
155 | |
02a73c96 |
156 | return ( |
157 | $args->{eval} ? ( eval "sub $src" || die $@ ) : $src, |
158 | $check_null_columns, |
159 | ); |
9f98c4b2 |
160 | } |
161 | |
162 | |
2d0b795a |
163 | # Takes an arrayref selection list and generates a collapse-map representing |
76031e14 |
164 | # row-object fold-points. Every relationship is assigned a set of unique, |
165 | # non-nullable columns (which may *not even be* from the same resultset) |
166 | # and the collapser will use this information to correctly distinguish |
2d0b795a |
167 | # data of individual to-be-row-objects. See t/resultset/rowparser_internals.t |
168 | # for extensive RV examples |
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169 | sub _resolve_collapse { |
82f0e0aa |
170 | my ($self, $args, $common_args) = @_; |
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171 | |
172 | # for comprehensible error messages put ourselves at the head of the relationship chain |
82f0e0aa |
173 | $args->{_rel_chain} ||= [ $self->source_name ]; |
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174 | |
9f98c4b2 |
175 | # record top-level fully-qualified column index, signify toplevelness |
176 | unless ($common_args->{_as_fq_idx}) { |
177 | $common_args->{_as_fq_idx} = { %{$args->{as}} }; |
178 | $args->{_is_top_level} = 1; |
82f0e0aa |
179 | }; |
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180 | |
181 | my ($my_cols, $rel_cols); |
82f0e0aa |
182 | for (keys %{$args->{as}}) { |
76031e14 |
183 | if ($_ =~ /^ ([^\.]+) \. (.+) /x) { |
184 | $rel_cols->{$1}{$2} = 1; |
185 | } |
186 | else { |
fcf32d04 |
187 | $my_cols->{$_} = {}; # important for ||='s below |
76031e14 |
188 | } |
189 | } |
190 | |
191 | my $relinfo; |
fcf32d04 |
192 | # run through relationships, collect metadata |
76031e14 |
193 | for my $rel (keys %$rel_cols) { |
76031e14 |
194 | my $inf = $self->relationship_info ($rel); |
195 | |
95e41036 |
196 | $relinfo->{$rel} = { |
197 | is_single => ( $inf->{attrs}{accessor} && $inf->{attrs}{accessor} ne 'multi' ), |
198 | is_inner => ( ( $inf->{attrs}{join_type} || '' ) !~ /^left/i), |
199 | rsrc => $self->related_source($rel), |
a4e58b18 |
200 | fk_map => $self->_resolve_relationship_condition( |
201 | rel_name => $rel, |
202 | self_alias => "\xFE", # irrelevant |
203 | foreign_alias => "\xFF", # irrelevant |
204 | )->{identity_map}, |
95e41036 |
205 | }; |
76031e14 |
206 | } |
207 | |
fcf32d04 |
208 | # inject non-left fk-bridges from *INNER-JOINED* children (if any) |
209 | for my $rel (grep { $relinfo->{$_}{is_inner} } keys %$relinfo) { |
210 | my $ri = $relinfo->{$rel}; |
211 | for (keys %{$ri->{fk_map}} ) { |
212 | # need to know source from *our* pov, hence $rel.col |
213 | $my_cols->{$_} ||= { via_fk => "$rel.$ri->{fk_map}{$_}" } |
214 | if defined $rel_cols->{$rel}{$ri->{fk_map}{$_}} # in fact selected |
215 | } |
216 | } |
217 | |
a0726a33 |
218 | # if the parent is already defined *AND* we have an inner reverse relationship |
219 | # (i.e. do not exist without it) , assume all of its related FKs are selected |
76031e14 |
220 | # (even if they in fact are NOT in the select list). Keep a record of what we |
221 | # assumed, and if any such phantom-column becomes part of our own collapser, |
222 | # throw everything assumed-from-parent away and replace with the collapser of |
223 | # the parent (whatever it may be) |
224 | my $assumed_from_parent; |
a0726a33 |
225 | if ( ! $args->{_parent_info}{underdefined} and ! $args->{_parent_info}{rev_rel_is_optional} ) { |
fcf32d04 |
226 | for my $col ( values %{$args->{_parent_info}{rel_condition} || {}} ) { |
227 | next if exists $my_cols->{$col}; |
228 | $my_cols->{$col} = { via_collapse => $args->{_parent_info}{collapse_on_idcols} }; |
229 | $assumed_from_parent->{columns}{$col}++; |
230 | } |
76031e14 |
231 | } |
232 | |
233 | # get colinfo for everything |
234 | if ($my_cols) { |
235 | my $ci = $self->columns_info; |
236 | $my_cols->{$_}{colinfo} = $ci->{$_} for keys %$my_cols; |
237 | } |
238 | |
239 | my $collapse_map; |
240 | |
3faac878 |
241 | # first try to reuse the parent's collapser (i.e. reuse collapser over 1:1) |
242 | # (makes for a leaner coderef later) |
9f98c4b2 |
243 | unless ($collapse_map->{-identifying_columns}) { |
244 | $collapse_map->{-identifying_columns} = $args->{_parent_info}{collapse_on_idcols} |
3faac878 |
245 | if $args->{_parent_info}{collapser_reusable}; |
246 | } |
247 | |
4a0eed52 |
248 | # Still don't know how to collapse - try to resolve based on our columns (plus already inserted FK bridges) |
76031e14 |
249 | if ( |
9f98c4b2 |
250 | ! $collapse_map->{-identifying_columns} |
3faac878 |
251 | and |
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252 | $my_cols |
253 | and |
4e9fc3f3 |
254 | my $idset = $self->_identifying_column_set ({map { $_ => $my_cols->{$_}{colinfo} } keys %$my_cols}) |
76031e14 |
255 | ) { |
256 | # see if the resulting collapser relies on any implied columns, |
257 | # and fix stuff up if this is the case |
4e9fc3f3 |
258 | my @reduced_set = grep { ! $assumed_from_parent->{columns}{$_} } @$idset; |
76031e14 |
259 | |
9f98c4b2 |
260 | $collapse_map->{-identifying_columns} = [ __unique_numlist( |
3faac878 |
261 | @{ $args->{_parent_info}{collapse_on_idcols}||[] }, |
262 | |
76031e14 |
263 | (map |
264 | { |
265 | my $fqc = join ('.', |
82f0e0aa |
266 | @{$args->{_rel_chain}}[1 .. $#{$args->{_rel_chain}}], |
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267 | ( $my_cols->{$_}{via_fk} || $_ ), |
268 | ); |
269 | |
82f0e0aa |
270 | $common_args->{_as_fq_idx}->{$fqc}; |
76031e14 |
271 | } |
4e9fc3f3 |
272 | @reduced_set |
76031e14 |
273 | ), |
3faac878 |
274 | )]; |
76031e14 |
275 | } |
276 | |
277 | # Stil don't know how to collapse - keep descending down 1:1 chains - if |
278 | # a related non-LEFT 1:1 is resolvable - its condition will collapse us |
279 | # too |
9f98c4b2 |
280 | unless ($collapse_map->{-identifying_columns}) { |
76031e14 |
281 | my @candidates; |
282 | |
283 | for my $rel (keys %$relinfo) { |
284 | next unless ($relinfo->{$rel}{is_single} && $relinfo->{$rel}{is_inner}); |
285 | |
82f0e0aa |
286 | if ( my $rel_collapse = $relinfo->{$rel}{rsrc}->_resolve_collapse ({ |
287 | as => $rel_cols->{$rel}, |
288 | _rel_chain => [ @{$args->{_rel_chain}}, $rel ], |
289 | _parent_info => { underdefined => 1 }, |
290 | }, $common_args)) { |
9f98c4b2 |
291 | push @candidates, $rel_collapse->{-identifying_columns}; |
76031e14 |
292 | } |
293 | } |
294 | |
295 | # get the set with least amount of columns |
296 | # FIXME - maybe need to implement a data type order as well (i.e. prefer several ints |
297 | # to a single varchar) |
298 | if (@candidates) { |
9f98c4b2 |
299 | ($collapse_map->{-identifying_columns}) = sort { scalar @$a <=> scalar @$b } (@candidates); |
76031e14 |
300 | } |
301 | } |
302 | |
fcf32d04 |
303 | # Stil don't know how to collapse, and we are the root node. Last ditch |
304 | # effort in case we are *NOT* premultiplied. |
305 | # Run through *each multi* all the way down, left or not, and all |
306 | # *left* singles (a single may become a multi underneath) . When everything |
307 | # gets back see if all the rels link to us definitively. If this is the |
308 | # case we are good - either one of them will define us, or if all are NULLs |
309 | # we know we are "unique" due to the "non-premultiplied" check |
310 | if ( |
9f98c4b2 |
311 | ! $collapse_map->{-identifying_columns} |
fcf32d04 |
312 | and |
313 | ! $args->{premultiplied} |
314 | and |
9f98c4b2 |
315 | $args->{_is_top_level} |
fcf32d04 |
316 | ) { |
317 | my (@collapse_sets, $uncollapsible_chain); |
318 | |
319 | for my $rel (keys %$relinfo) { |
320 | |
321 | # we already looked at these higher up |
322 | next if ($relinfo->{$rel}{is_single} && $relinfo->{$rel}{is_inner}); |
323 | |
324 | if (my $clps = $relinfo->{$rel}{rsrc}->_resolve_collapse ({ |
325 | as => $rel_cols->{$rel}, |
326 | _rel_chain => [ @{$args->{_rel_chain}}, $rel ], |
327 | _parent_info => { underdefined => 1 }, |
328 | }, $common_args) ) { |
329 | |
330 | # for singles use the idcols wholesale (either there or not) |
331 | if ($relinfo->{$rel}{is_single}) { |
9f98c4b2 |
332 | push @collapse_sets, $clps->{-identifying_columns}; |
fcf32d04 |
333 | } |
334 | elsif (! $relinfo->{$rel}{fk_map}) { |
335 | $uncollapsible_chain = 1; |
336 | last; |
337 | } |
338 | else { |
339 | my $defined_cols_parent_side; |
340 | |
341 | for my $fq_col ( grep { /^$rel\.[^\.]+$/ } keys %{$args->{as}} ) { |
342 | my ($col) = $fq_col =~ /([^\.]+)$/; |
343 | |
344 | $defined_cols_parent_side->{$_} = $args->{as}{$fq_col} for grep |
345 | { $relinfo->{$rel}{fk_map}{$_} eq $col } |
346 | keys %{$relinfo->{$rel}{fk_map}} |
347 | ; |
348 | } |
349 | |
350 | if (my $set = $self->_identifying_column_set([ keys %$defined_cols_parent_side ]) ) { |
351 | push @collapse_sets, [ sort map { $defined_cols_parent_side->{$_} } @$set ]; |
352 | } |
353 | else { |
354 | $uncollapsible_chain = 1; |
355 | last; |
356 | } |
357 | } |
358 | } |
359 | else { |
360 | $uncollapsible_chain = 1; |
361 | last; |
362 | } |
363 | } |
364 | |
365 | unless ($uncollapsible_chain) { |
366 | # if we got here - we are good to go, but the construction is tricky |
367 | # since our children will want to include our collapse criteria - we |
368 | # don't give them anything (safe, since they are all collapsible on their own) |
4a0eed52 |
369 | # in addition we record the individual collapse possibilities |
fcf32d04 |
370 | # of all left children node collapsers, and merge them in the rowparser |
371 | # coderef later |
9f98c4b2 |
372 | $collapse_map->{-identifying_columns} = []; |
373 | $collapse_map->{-identifying_columns_variants} = [ sort { |
fcf32d04 |
374 | (scalar @$a) <=> (scalar @$b) or max(@$a) <=> max(@$b) |
375 | } @collapse_sets ]; |
376 | } |
377 | } |
378 | |
76031e14 |
379 | # stop descending into children if we were called by a parent for first-pass |
380 | # and don't despair if nothing was found (there may be other parallel branches |
381 | # to dive into) |
82f0e0aa |
382 | if ($args->{_parent_info}{underdefined}) { |
9f98c4b2 |
383 | return $collapse_map->{-identifying_columns} ? $collapse_map : undef |
76031e14 |
384 | } |
385 | # nothing down the chain resolved - can't calculate a collapse-map |
9f98c4b2 |
386 | elsif (! $collapse_map->{-identifying_columns}) { |
76031e14 |
387 | $self->throw_exception ( sprintf |
388 | "Unable to calculate a definitive collapse column set for %s%s: fetch more unique non-nullable columns", |
389 | $self->source_name, |
82f0e0aa |
390 | @{$args->{_rel_chain}} > 1 |
391 | ? sprintf (' (last member of the %s chain)', join ' -> ', @{$args->{_rel_chain}} ) |
76031e14 |
392 | : '' |
393 | , |
394 | ); |
395 | } |
396 | |
397 | # If we got that far - we are collapsable - GREAT! Now go down all children |
398 | # a second time, and fill in the rest |
399 | |
a0726a33 |
400 | $collapse_map->{-identifying_columns} = [ __unique_numlist( |
401 | @{ $args->{_parent_info}{collapse_on_idcols}||[] }, |
402 | @{ $collapse_map->{-identifying_columns} }, |
403 | )]; |
3faac878 |
404 | |
405 | my @id_sets; |
76031e14 |
406 | for my $rel (sort keys %$relinfo) { |
407 | |
82f0e0aa |
408 | $collapse_map->{$rel} = $relinfo->{$rel}{rsrc}->_resolve_collapse ({ |
409 | as => { map { $_ => 1 } ( keys %{$rel_cols->{$rel}} ) }, |
410 | _rel_chain => [ @{$args->{_rel_chain}}, $rel], |
411 | _parent_info => { |
3faac878 |
412 | # shallow copy |
9f98c4b2 |
413 | collapse_on_idcols => [ @{$collapse_map->{-identifying_columns}} ], |
76031e14 |
414 | |
415 | rel_condition => $relinfo->{$rel}{fk_map}, |
416 | |
a0726a33 |
417 | is_optional => ! $relinfo->{$rel}{is_inner}, |
418 | |
419 | # if there is at least one *inner* reverse relationship which is HASH-based (equality only) |
420 | # we can safely assume that the child can not exist without us |
421 | rev_rel_is_optional => ( first |
422 | { ref $_->{cond} eq 'HASH' and ($_->{attrs}{join_type}||'') !~ /^left/i } |
423 | values %{ $self->reverse_relationship_info($rel) }, |
424 | ) ? 0 : 1, |
76031e14 |
425 | |
426 | # if this is a 1:1 our own collapser can be used as a collapse-map |
427 | # (regardless of left or not) |
3d8caf63 |
428 | collapser_reusable => ( |
429 | $relinfo->{$rel}{is_single} |
430 | && |
431 | $relinfo->{$rel}{is_inner} |
432 | && |
433 | @{$collapse_map->{-identifying_columns}} |
434 | ) ? 1 : 0, |
76031e14 |
435 | }, |
82f0e0aa |
436 | }, $common_args ); |
76031e14 |
437 | |
438 | $collapse_map->{$rel}{-is_single} = 1 if $relinfo->{$rel}{is_single}; |
439 | $collapse_map->{$rel}{-is_optional} ||= 1 unless $relinfo->{$rel}{is_inner}; |
3faac878 |
440 | } |
76031e14 |
441 | |
442 | return $collapse_map; |
443 | } |
444 | |
76031e14 |
445 | # adding a dep on MoreUtils *just* for this is retarded |
446 | sub __unique_numlist { |
3faac878 |
447 | sort { $a <=> $b } keys %{ {map { $_ => 1 } @_ }} |
76031e14 |
448 | } |
449 | |
76031e14 |
450 | 1; |