X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=scpubgit%2FQ-Branch.git;a=blobdiff_plain;f=lib%2FSQL%2FAbstract%2FExtraClauses.pm;h=9c2784539387247910d19bae5ebb0f6646d86758;hp=b5f15d9c2643ba260f55c76b11e6ea10cb6084cf;hb=4979c509c66eb5c81887d3afe37de54f0988ad94;hpb=2f4717adc025a309b4137256f09344c853566630 diff --git a/lib/SQL/Abstract/ExtraClauses.pm b/lib/SQL/Abstract/ExtraClauses.pm index b5f15d9..9c27845 100644 --- a/lib/SQL/Abstract/ExtraClauses.pm +++ b/lib/SQL/Abstract/ExtraClauses.pm @@ -5,21 +5,40 @@ use Moo; has sqla => ( is => 'ro', init_arg => undef, handles => [ qw( - expand_expr expand_maybe_list_expr render_aqt - format_keyword join_query_parts + expand_expr expand_maybe_list_expr render_aqt join_query_parts ) ], ); -BEGIN { *puke = \&SQL::Abstract::puke } - sub cb { - my ($self, $method) = @_; - return sub { local $self->{sqla} = shift; $self->$method(@_) }; + my ($self, $method, @args) = @_; + return sub { + local $self->{sqla} = shift; + $self->$method(@args, @_) + }; +} + +sub register { + my ($self, @pairs) = @_; + my $sqla = $self->sqla; + while (my ($method, $cases) = splice(@pairs, 0, 2)) { + my @cases = @$cases; + while (my ($name, $case) = splice(@cases, 0, 2)) { + $sqla->$method($name, $self->cb($case)); + } + } + return $self; } sub apply_to { my ($self, $sqla) = @_; $self = $self->new unless ref($self); + local $self->{sqla} = $sqla; + $self->register_extensions($sqla); +} + +sub register_extensions { + my ($self, $sqla) = @_; + my @clauses = $sqla->clauses_of('select'); my @before_setop; CLAUSE: foreach my $idx (0..$#clauses) { @@ -29,23 +48,9 @@ sub apply_to { last CLAUSE; } } + die "Huh?" unless @before_setop; - $sqla->clauses_of(select => 'with', @clauses); - $sqla->clause_expanders( - 'select.group_by', $self->cb(sub { - $_[0]->expand_maybe_list_expr($_[2], -ident) - }), - 'select.having', $self->cb(sub { $_[0]->expand_expr($_[2]) }), - ); - foreach my $thing (qw(join from_list)) { - $sqla->expander($thing => $self->cb("_expand_${thing}")) - ->renderer($thing => $self->cb("_render_${thing}")) - } - $sqla->op_expander(as => $self->cb('_expand_op_as')); - $sqla->expander(as => $self->cb('_expand_op_as')); - $sqla->renderer(as => $self->cb('_render_as')); - $sqla->expander(alias => $self->cb('_expand_alias')); - $sqla->renderer(alias => $self->cb('_render_alias')); + $sqla->clauses_of(select => @clauses); $sqla->clauses_of(update => sub { my ($self, @clauses) = @_; @@ -59,66 +64,51 @@ sub apply_to { @clauses; }); - $sqla->clause_expanders( - 'update.from' => $self->cb('_expand_select_clause_from'), - 'delete.using' => $self->cb(sub { - +(using => $_[0]->_expand_from_list(undef, $_[2])); - }), - 'insert.rowvalues' => $self->cb(sub { - +(from => $_[0]->expand_expr({ -values => $_[2] })); - }), - 'insert.select' => $self->cb(sub { - +(from => $_[0]->expand_expr({ -select => $_[2] })); - }), + $self->register( + (map +( + "${_}er" => [ + do { + my $x = $_; + (map +($_ => "_${x}_${_}"), qw(join from_list alias)) + } + ] + ), qw(expand render)), + binop_expander => [ as => '_expand_op_as' ], + renderer => [ as => '_render_as' ], + expander => [ cast => '_expand_cast' ], + clause_expanders => [ + "select.from", '_expand_from_list', + 'select.group_by' + => sub { $_[0]->expand_maybe_list_expr($_[2], -ident) }, + 'select.having' + => sub { $_[0]->expand_expr($_[2]) }, + 'update.from' => '_expand_from_list', + "update.target", '_expand_update_clause_target', + "update.update", '_expand_update_clause_target', + 'delete.using' => '_expand_from_list', + 'insert.rowvalues' => sub { + +(from => $_[0]->expand_expr({ -values => $_[2] })); + }, + 'insert.select' => sub { + +(from => $_[0]->expand_expr({ -select => $_[2] })); + }, + ], ); # set ops $sqla->wrap_expander(select => sub { - my $orig = shift; - $self->cb(sub { - my $self = shift; - my $exp = $self->sqla->$orig(@_); - return $exp unless my $setop = (my $sel = $exp->{-select})->{setop}; - if (my @keys = grep $sel->{$_}, @before_setop) { - my %inner; @inner{@keys} = delete @{$sel}{@keys}; - unshift @{(values(%$setop))[0]{queries}}, - { -select => \%inner }; - } - return $exp; - }); - }); - my $expand_setop = $self->cb(sub { - my ($self, $setop, $args) = @_; - +{ "-${setop}" => { - %$args, - queries => [ map $self->expand_expr($_), @{$args->{queries}} ], - } }; + $self->cb('_expand_select', $_[0], \@before_setop); }); - $sqla->expanders(map +($_ => $expand_setop), qw(union intersect except)); - $sqla->clause_renderer('select.setop' => $self->cb(sub { - my ($self, undef, $setop) = @_; - $self->render_aqt($setop); - })); + $self->register( + clause_renderer => [ + 'select.setop' => sub { $_[0]->render_aqt($_[2]) } + ], + expander => [ map +($_ => '_expand_setop'), qw(union intersect except) ], + renderer => [ map +($_ => '_render_setop'), qw(union intersect except) ], + ); - $sqla->renderer($_ => $self->cb(sub { - my ($self, $setop, $args) = @_; - $self->join_query_parts( - ' '.$self->format_keyword(join '_', $setop, ($args->{type}||())).' ', - @{$args->{queries}} - ); - })) for qw(union intersect except); - - my $setop_expander = $self->cb(sub { - my ($self, $setop, $args) = @_; - my ($op, $type) = split '_', $setop; - +(setop => $self->expand_expr({ - "-${op}" => { - ($type ? (type => $type) : ()), - queries => (ref($args) eq 'ARRAY' ? $args : [ $args ]) - } - })); - }); + my $setop_expander = $self->cb('_expand_clause_setop'); $sqla->clause_expanders( map +($_ => $setop_expander), @@ -127,33 +117,30 @@ sub apply_to { qw(union intersect except) ); - my $w_exp = $self->cb('_expand_with'); - my $w_rdr = $self->cb('_render_with'); - $sqla->clause_expander('select.with' => $w_exp); - $sqla->clause_expander('select.with_recursive' => $w_exp); - $sqla->clause_renderer('select.with' => $w_rdr); - - foreach my $stmt (qw(insert update delete)) { + foreach my $stmt (qw(select insert update delete)) { $sqla->clauses_of($stmt => 'with', $sqla->clauses_of($stmt)); - $sqla->clause_expander("${stmt}.$_" => $w_exp) - for qw(with with_recursive); - $sqla->clause_renderer("${stmt}.with" => $w_rdr); + $self->register( + clause_expanders => [ + "${stmt}.with" => '_expand_with', + "${stmt}.with_recursive" => '_expand_with', + ], + clause_renderer => [ "${stmt}.with" => '_render_with' ], + ); } - $sqla->expander(cast => $self->cb('_expand_cast')); - - $sqla->clause_expanders( - "select.from", $self->cb('_expand_select_clause_from'), - "update.target", $self->cb('_expand_update_clause_target'), - "update.update", $self->cb('_expand_update_clause_target'), - ); - return $sqla; } -sub _expand_select_clause_from { - my ($self, undef, $from) = @_; - +(from => $self->_expand_from_list(undef, $from)); +sub _expand_select { + my ($self, $orig, $before_setop, @args) = @_; + my $exp = $self->sqla->$orig(@args); + return $exp unless my $setop = (my $sel = $exp->{-select})->{setop}; + if (my @keys = grep $sel->{$_}, @$before_setop) { + my %inner; @inner{@keys} = delete @{$sel}{@keys}; + unshift @{(values(%$setop))[0]{queries}}, + { -select => \%inner }; + } + return $exp; } sub _expand_from_list { @@ -180,6 +167,7 @@ sub _expand_from_list { } push @list, $aqt; } + return $list[0] if @list == 1; return { -from_list => \@list }; } @@ -188,10 +176,12 @@ sub _expand_join { my %proto = ( ref($args) eq 'HASH' ? %$args - : (to => $args->[0], @{$args}[1..$#$args]) + : (to => @$args) ); if (my $as = delete $proto{as}) { - $proto{to} = $self->expand_expr({ -as => [ $proto{to}, $as ] }); + $proto{to} = $self->expand_expr( + { -as => [ { -from_list => $proto{to} }, $as ] } + ); } if (defined($proto{using}) and ref(my $using = $proto{using}) ne 'HASH') { $proto{using} = [ @@ -199,8 +189,14 @@ sub _expand_join { ref($using) eq 'ARRAY' ? @$using: $using ]; } - my %ret = map +($_ => $self->expand_expr($proto{$_}, -ident)), - sort keys %proto; + my %ret = ( + type => delete $proto{type}, + to => $self->expand_expr({ -from_list => delete $proto{to} }, -ident) + ); + %ret = (%ret, + map +($_ => $self->expand_expr($proto{$_}, -ident)), + sort keys %proto + ); return +{ -join => \%ret }; } @@ -214,14 +210,19 @@ sub _render_join { my @parts = ( $args->{from}, - $self->format_keyword(join '_', ($args->{type}||()), 'join'), - (map +($_->{-ident} || $_->{-as} ? $_ : ('(', $_, ')')), $args->{to}), + { -keyword => join '_', ($args->{type}||()), 'join' }, + (map +($_->{-ident} || $_->{-as} + ? $_ + : ('(', $self->render_aqt($_, 1), ')')), + map +(@{$_->{-from_list}||[]} == 1 ? $_->{-from_list}[0] : $_), + $args->{to} + ), ($args->{on} ? ( - $self->format_keyword('on') , + { -keyword => 'on' }, $args->{on}, ) : ()), ($args->{using} ? ( - $self->format_keyword('using'), + { -keyword => 'using' }, '(', $args->{using}, ')', ) : ()), ); @@ -231,13 +232,12 @@ sub _render_join { sub _expand_op_as { my ($self, undef, $vv, $k) = @_; my @vv = (ref($vv) eq 'ARRAY' ? @$vv : $vv); - $k ||= shift @vv; my $ik = $self->expand_expr($k, -ident); - return +{ -as => [ $ik, $self->expand_expr($vv[0], -alias) ] } + return +{ -as => [ $ik, $self->expand_expr($vv[0], -ident) ] } if @vv == 1 and ref($vv[0]) eq 'HASH'; my @as = map $self->expand_expr($_, -ident), @vv; - return { -as => [ $ik, { -alias => \@as } ] }; + return { -as => [ $ik, $self->expand_expr({ -alias => \@as }) ] }; } sub _render_as { @@ -246,7 +246,7 @@ sub _render_as { return $self->join_query_parts( ' ', $thing, - $self->format_keyword('as'), + { -keyword => 'as' }, $alias, ); } @@ -288,11 +288,10 @@ sub _expand_alias { if (ref($args) eq 'HASH' and my $alias = $args->{-alias}) { $args = $alias; } - +{ -alias => [ - map $self->expand_expr($_, -ident), - ref($args) eq 'ARRAY' ? @{$args} : $args - ] - } + my @parts = map $self->expand_expr($_, -ident), + ref($args) eq 'ARRAY' ? @{$args} : $args; + return $parts[0] if @parts == 1; + return { -alias => \@parts }; } sub _expand_with { @@ -327,15 +326,253 @@ sub _render_with { my ($alias, $query) = @$_; $self->join_query_parts(' ', $alias, - $self->format_keyword('as'), + { -keyword => 'as' }, $query, ) } @{$with->{queries}} ); return $self->join_query_parts(' ', - $self->format_keyword(join '_', 'with', ($with->{type}||'')), + { -keyword => join '_', 'with', ($with->{type}||'') }, $q_part, ); } +sub _expand_setop { + my ($self, $setop, $args) = @_; + +{ "-${setop}" => { + %$args, + queries => [ map $self->expand_expr($_), @{$args->{queries}} ], + } }; +} + +sub _render_setop { + my ($self, $setop, $args) = @_; + $self->join_query_parts( + { -keyword => ' '.join('_', $setop, ($args->{type}||())).' ' }, + @{$args->{queries}} + ); +} + +sub _expand_clause_setop { + my ($self, $setop, $args) = @_; + my ($op, $type) = split '_', $setop; + +(setop => $self->expand_expr({ + "-${op}" => { + ($type ? (type => $type) : ()), + queries => (ref($args) eq 'ARRAY' ? $args : [ $args ]) + } + })); +} + 1; + +__END__ + +=head1 NAME + +SQL::Abstract::ExtraClauses - new/experimental additions to L + +=head1 SYNOPSIS + + my $sqla = SQL::Abstract->new; + SQL::Abstract::ExtraClauses->apply_to($sqla); + +=head1 METHODS + +=head2 apply_to + +Applies the plugin to an L object. + +=head2 register_extensions + +Registers the extensions described below + +=head2 cb + +For plugin authors, creates a callback to call a method on the plugin. + +=head2 register + +For plugin authors, registers callbacks more easily. + +=head2 sqla + +Available only during plugin callback executions, contains the currently +active L object. + +=head1 NODE TYPES + +=head2 alias + +Represents a table alias. Expands name and column names with ident as default. + + # expr + { -alias => [ 't', 'x', 'y', 'z' ] } + + # aqt + { -alias => [ + { -ident => [ 't' ] }, { -ident => [ 'x' ] }, + { -ident => [ 'y' ] }, { -ident => [ 'z' ] }, + ] } + + # query + t(x, y, z) + [] + +=head2 as + +Represents an sql AS. LHS is expanded with ident as default, RHS is treated +as a list of arguments for the alias node. + + # expr + { foo => { -as => 'bar' } } + + # aqt + { -as => [ { -ident => [ 'foo' ] }, { -ident => [ 'bar' ] } ] } + + # query + foo AS bar + [] + + # expr + { -as => [ { -select => { _ => 'blah' } }, 't', 'blah' ] } + + # aqt + { -as => [ + { -select => + { select => { -op => [ ',', { -ident => [ 'blah' ] } ] } } + }, + { -alias => [ { -ident => [ 't' ] }, { -ident => [ 'blah' ] } ] }, + ] } + + # query + (SELECT blah) AS t(blah) + [] + +=head2 cast + + # expr + { -cast => [ { -ident => 'birthday' }, 'date' ] } + + # aqt + { -func => [ + 'cast', { + -as => [ { -ident => [ 'birthday' ] }, { -ident => [ 'date' ] } ] + }, + ] } + + # query + CAST(birthday AS date) + [] + +=head2 join + +If given an arrayref, pretends it was given a hashref with the first +element of the arrayref as the value for 'to' and the remaining pairs copied. + +Given a hashref, the 'as' key is if presented expanded to wrap the 'to'. + +If present the 'using' key is expanded as a list of idents. + +Known keys are: 'from' (the left hand side), 'type' ('left', 'right', or +nothing), 'to' (the right hand side), 'on' and 'using'. + + # expr + { -join => { + from => 'lft', + on => { 'lft.bloo' => { '>' => 'rgt.blee' } }, + to => 'rgt', + type => 'left', + } } + + # aqt + { -join => { + from => { -ident => [ 'lft' ] }, + on => { -op => [ + '>', { -ident => [ 'lft', 'bloo' ] }, + { -ident => [ 'rgt', 'blee' ] }, + ] }, + to => { -ident => [ 'rgt' ] }, + type => 'left', + } } + + # query + lft LEFT JOIN rgt ON lft.bloo > rgt.blee + [] + +=head2 from_list + +List of components of the FROM clause; -foo type elements indicate a pair +with the next element; this is easiest if I show you: + + # expr + { -from_list => [ + 't1', -as => 'table_one', -join => + [ 't2', 'on', { 'table_one.x' => 't2.x' } ], + ] } + + # aqt + { -join => { + from => + { + -as => [ { -ident => [ 't1' ] }, { -ident => [ 'table_one' ] } ] + }, + on => { -op => [ + '=', { -ident => [ 'table_one', 'x' ] }, + { -ident => [ 't2', 'x' ] }, + ] }, + to => { -ident => [ 't2' ] }, + type => undef, + } } + + # query + t1 AS table_one JOIN t2 ON table_one.x = t2.x + [] + +Or with using: + + # expr + { -from_list => + [ 't1', -as => 'table_one', -join => [ 't2', 'using', [ 'x' ] ] ] + } + + # aqt + { -join => { + from => + { + -as => [ { -ident => [ 't1' ] }, { -ident => [ 'table_one' ] } ] + }, + to => { -ident => [ 't2' ] }, + type => undef, + using => + { -op => [ 'or', { -op => [ 'or', { -ident => [ 'x' ] } ] } ] }, + } } + + # query + t1 AS table_one JOIN t2 USING ( x ) + [] + +With oddities: + + # expr + { -from_list => [ + 'x', -join => + [ [ 'y', -join => [ 'z', 'type', 'left' ] ], 'type', 'left' ], + ] } + + # aqt + { -join => { + from => { -ident => [ 'x' ] }, + to => { -join => { + from => { -ident => [ 'y' ] }, + to => { -ident => [ 'z' ] }, + type => 'left', + } }, + type => 'left', + } } + + # query + x LEFT JOIN ( y LEFT JOIN z ) + [] + +=cut