X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FDBIx%2FClass%2FResultSource.pm;h=4331a153f1ca583a880eb15e57b6651acc59735c;hb=bcd264195a5ab28e03232464f786c155524a12a9;hp=a7a802b25055157e5c5abbc1ef44396ae11e18da;hpb=571dced30707f6cf20e15f8eee0e4cb987c45fd1;p=dbsrgits%2FDBIx-Class.git diff --git a/lib/DBIx/Class/ResultSource.pm b/lib/DBIx/Class/ResultSource.pm index a7a802b..4331a15 100644 --- a/lib/DBIx/Class/ResultSource.pm +++ b/lib/DBIx/Class/ResultSource.pm @@ -4,14 +4,15 @@ use strict; use warnings; use DBIx::Class::ResultSet; - -use Carp qw/croak/; +use Carp::Clan qw/^DBIx::Class/; +use Storable; use base qw/DBIx::Class/; __PACKAGE__->load_components(qw/AccessorGroup/); __PACKAGE__->mk_group_accessors('simple' => - qw/_ordered_columns _columns _primaries name resultset_class result_class schema from/); + qw/_ordered_columns _columns _primaries _unique_constraints name resultset_attributes schema from _relationships/); +__PACKAGE__->mk_group_accessors('component_class' => qw/resultset_class result_class/); =head1 NAME @@ -31,25 +32,18 @@ retrieved, most usually a table (see L) sub new { my ($class, $attrs) = @_; $class = ref $class if ref $class; - my $new = bless({ %{$attrs || {}} }, $class); + my $new = bless({ %{$attrs || {}}, _resultset => undef }, $class); $new->{resultset_class} ||= 'DBIx::Class::ResultSet'; - $new->{_ordered_columns} ||= []; - $new->{_columns} ||= {}; + $new->{resultset_attributes} = { %{$new->{resultset_attributes} || {}} }; + $new->{_ordered_columns} = [ @{$new->{_ordered_columns}||[]}]; + $new->{_columns} = { %{$new->{_columns}||{}} }; + $new->{_relationships} = { %{$new->{_relationships}||{}} }; $new->{name} ||= "!!NAME NOT SET!!"; + $new->{_columns_info_loaded} ||= 0; return $new; } -sub add_columns { - my ($self, @cols) = @_; - $self->_ordered_columns( \@cols ) - if !$self->_ordered_columns; - push @{ $self->_ordered_columns }, @cols; - while (my $col = shift @cols) { - $self->_columns->{$col} = (ref $cols[0] ? shift : {}); - } -} - -*add_column = \&add_columns; +=pod =head2 add_columns @@ -60,6 +54,66 @@ sub add_columns { Adds columns to the result source. If supplied key => hashref pairs uses the hashref as the column_info for that column. +Repeated calls of this method will add more columns, not replace them. + +The contents of the column_info are not set in stone, the following +keys are currently recognised/used by DBIx::Class. + +=over 4 + +=item accessor + +Use this to set the name of the accessor for this column. If unset, +the name of the column will be used. + +=item data_type + +This contains the column type, it is automatically filled by the +L producer, and the +L module. If you do not enter the +data_type, DBIx::Class will attempt to retrieve it from the +database for you, using Ls column_info method. The values of this +key are typically upper-cased. + +Currently there is no standard set of values for the data_type, use +whatever your database(s) support. + +=item size + +The length of your column, if it is a column type that can have a size +restriction. This is currently not used by DBIx::Class. + +=item is_nullable + +If the column is allowed to contain NULL values, set a true value +(typically 1), here. This is currently not used by DBIx::Class. + +=item is_auto_increment + +Set this to a true value if this is a column that is somehow +automatically filled. This is currently not used by DBIx::Class. + +=item is_foreign_key + +Set this to a true value if this column represents a key from a +foreign table. This is currently not used by DBIx::Class. + +=item default_value + +Set this to the default value which will be inserted into this column +by the database. Can contain either values or functions. This is +currently not used by DBIx::Class. + +=item sequence + +If your column is using a sequence to create it's values, set the name +of the sequence here, to allow the values to be retrieved +automatically by the L module. PK::Auto will +attempt to retrieve the sequence name from the database, if this value +is left unset. + +=back + =head2 add_column $table->add_column('col' => \%info?); @@ -68,89 +122,155 @@ Convenience alias to add_columns =cut -sub resultset { - my $self = shift; - return $self->resultset_class->new($self); +sub add_columns { + my ($self, @cols) = @_; + $self->_ordered_columns(\@cols) unless $self->_ordered_columns; + + my @added; + my $columns = $self->_columns; + while (my $col = shift @cols) { + # If next entry is { ... } use that for the column info, if not + # use an empty hashref + my $column_info = ref $cols[0] ? shift(@cols) : {}; + push(@added, $col) unless exists $columns->{$col}; + $columns->{$col} = $column_info; + } + push @{ $self->_ordered_columns }, @added; + return $self; } -=head2 has_column - - if ($obj->has_column($col)) { ... } - +*add_column = \&add_columns; + +=head2 has_column + + if ($obj->has_column($col)) { ... } + Returns 1 if the source has a column of this name, 0 otherwise. - -=cut + +=cut sub has_column { my ($self, $column) = @_; return exists $self->_columns->{$column}; } -=head2 column_info +=head2 column_info + + my $info = $obj->column_info($col); - my $info = $obj->column_info($col); +Returns the column metadata hashref for a column. See the description +of add_column for information on the contents of the hashref. -Returns the column metadata hashref for a column. - -=cut +=cut sub column_info { my ($self, $column) = @_; - croak "No such column $column" unless exists $self->_columns->{$column}; + $self->throw_exception("No such column $column") + unless exists $self->_columns->{$column}; + #warn $self->{_columns_info_loaded}, "\n"; + if ( ! $self->_columns->{$column}{data_type} + and ! $self->{_columns_info_loaded} + and $self->schema and $self->storage ) + { + $self->{_columns_info_loaded}++; + my $info; + # eval for the case of storage without table + eval { $info = $self->storage->columns_info_for($self->from) }; + unless ($@) { + foreach my $col ( keys %{$self->_columns} ) { + foreach my $i ( keys %{$info->{$col}} ) { + $self->_columns->{$col}{$i} = $info->{$col}{$i}; + } + } + } + } return $self->_columns->{$column}; } =head2 columns - my @column_names = $obj->columns; - -=cut + my @column_names = $obj->columns; + +Returns all column names in the order they were declared to add_columns + +=cut sub columns { - croak "columns() is a read-only accessor, did you mean add_columns()?" if (@_ > 1); - return keys %{shift->_columns}; + my $self = shift; + $self->throw_exception("columns() is a read-only accessor, did you mean add_columns()?") if (@_ > 1); + return @{$self->{_ordered_columns}||[]}; } -=head2 ordered_columns +=head2 set_primary_key - my @column_names = $obj->ordered_columns; +=head3 Arguments: (@cols) -Like columns(), but returns column names using the order in which they were -originally supplied to add_columns(). +Defines one or more columns as primary key for this source. Should be +called after C. -=cut +Additionally, defines a unique constraint named C. -sub ordered_columns { - return @{shift->{_ordered_columns}||[]}; -} +The primary key columns are used by L to +retrieve automatically created values from the database. -=head2 set_primary_key(@cols) - -Defines one or more columns as primary key for this source. Should be -called after C. - -=cut +=cut sub set_primary_key { my ($self, @cols) = @_; # check if primary key columns are valid columns - for (@cols) { - $self->throw("No such column $_ on table ".$self->name) - unless $self->has_column($_); + foreach my $col (@cols) { + $self->throw_exception("No such column $col on table " . $self->name) + unless $self->has_column($col); } $self->_primaries(\@cols); + + $self->add_unique_constraint(primary => \@cols); } -=head2 primary_columns - +=head2 primary_columns + Read-only accessor which returns the list of primary keys. - -=cut + +=cut sub primary_columns { return @{shift->_primaries||[]}; } +=head2 add_unique_constraint + +Declare a unique constraint on this source. Call once for each unique +constraint. Unique constraints are used when you call C on a +L, only columns in the constraint are searched, + + # For e.g. UNIQUE (column1, column2) + __PACKAGE__->add_unique_constraint(constraint_name => [ qw/column1 column2/ ]); + +=cut + +sub add_unique_constraint { + my ($self, $name, $cols) = @_; + + foreach my $col (@$cols) { + $self->throw_exception("No such column $col on table " . $self->name) + unless $self->has_column($col); + } + + my %unique_constraints = $self->unique_constraints; + $unique_constraints{$name} = $cols; + $self->_unique_constraints(\%unique_constraints); +} + +=head2 unique_constraints + +Read-only accessor which returns the list of unique constraints on this source. + +=cut + +sub unique_constraints { + return %{shift->_unique_constraints||{}}; +} + =head2 from Returns an expression of the source to be supplied to storage to specify @@ -161,13 +281,375 @@ contents. =head2 storage -Returns the storage handle for the current schema +Returns the storage handle for the current schema. + +See also: L =cut sub storage { shift->schema->storage; } -1; +=head2 add_relationship + + $source->add_relationship('relname', 'related_source', $cond, $attrs); + +The relation name can be arbitrary, but must be unique for each relationship +attached to this result source. 'related_source' should be the name with +which the related result source was registered with the current schema +(for simple schemas this is usally either Some::Namespace::Foo or just Foo) + +The condition needs to be an SQL::Abstract-style representation of the join +between the tables. For example, if you're creating a rel from Author to Book, + + { 'foreign.author_id' => 'self.id' } + +will result in the JOIN clause + + author me JOIN book foreign ON foreign.author_id = me.id + +You can specify as many foreign => self mappings as necessary. + +Valid attributes are as follows: + +=over 4 + +=item join_type + +Explicitly specifies the type of join to use in the relationship. Any +SQL join type is valid, e.g. C or C. It will be placed in +the SQL command immediately before C. + +=item proxy + +An arrayref containing a list of accessors in the foreign class to +proxy in the main class. If, for example, you do the following: + + __PACKAGE__->might_have(bar => 'Bar', undef, { proxy => [ qw/margle/] }); + +Then, assuming Bar has an accessor named margle, you can do: + + my $obj = Foo->find(1); + $obj->margle(10); # set margle; Bar object is created if it doesn't exist + +=item accessor + +Specifies the type of accessor that should be created for the +relationship. Valid values are C (for when there is only a single +related object), C (when there can be many), and C (for +when there is a single related object, but you also want the relationship +accessor to double as a column accessor). For C accessors, an +add_to_* method is also created, which calls C for the +relationship. + +=back + +=cut + +sub add_relationship { + my ($self, $rel, $f_source_name, $cond, $attrs) = @_; + $self->throw_exception("Can't create relationship without join condition") unless $cond; + $attrs ||= {}; + + my %rels = %{ $self->_relationships }; + $rels{$rel} = { class => $f_source_name, + source => $f_source_name, + cond => $cond, + attrs => $attrs }; + $self->_relationships(\%rels); + + return $self; + + # XXX disabled. doesn't work properly currently. skip in tests. + + my $f_source = $self->schema->source($f_source_name); + unless ($f_source) { + eval "require $f_source_name;"; + if ($@) { + die $@ unless $@ =~ /Can't locate/; + } + $f_source = $f_source_name->result_source; + #my $s_class = ref($self->schema); + #$f_source_name =~ m/^${s_class}::(.*)$/; + #$self->schema->register_class(($1 || $f_source_name), $f_source_name); + #$f_source = $self->schema->source($f_source_name); + } + return unless $f_source; # Can't test rel without f_source + + eval { $self->resolve_join($rel, 'me') }; + + if ($@) { # If the resolve failed, back out and re-throw the error + delete $rels{$rel}; # + $self->_relationships(\%rels); + $self->throw_exception("Error creating relationship $rel: $@"); + } + 1; +} + +=head2 relationships + +Returns all valid relationship names for this source + +=cut + +sub relationships { + return keys %{shift->_relationships}; +} + +=head2 relationship_info + +=head3 Arguments: ($relname) + +Returns the relationship information for the specified relationship name + +=cut + +sub relationship_info { + my ($self, $rel) = @_; + return $self->_relationships->{$rel}; +} + +=head2 has_relationship + +=head3 Arguments: ($rel) + +Returns 1 if the source has a relationship of this name, 0 otherwise. + +=cut + +sub has_relationship { + my ($self, $rel) = @_; + return exists $self->_relationships->{$rel}; +} + +=head2 resolve_join + +=head3 Arguments: ($relation) + +Returns the join structure required for the related result source + +=cut + +sub resolve_join { + my ($self, $join, $alias, $seen) = @_; + $seen ||= {}; + if (ref $join eq 'ARRAY') { + return map { $self->resolve_join($_, $alias, $seen) } @$join; + } elsif (ref $join eq 'HASH') { + return + map { + my $as = ($seen->{$_} ? $_.'_'.($seen->{$_}+1) : $_); + ($self->resolve_join($_, $alias, $seen), + $self->related_source($_)->resolve_join($join->{$_}, $as, $seen)); + } keys %$join; + } elsif (ref $join) { + $self->throw_exception("No idea how to resolve join reftype ".ref $join); + } else { + my $count = ++$seen->{$join}; + #use Data::Dumper; warn Dumper($seen); + my $as = ($count > 1 ? "${join}_${count}" : $join); + my $rel_info = $self->relationship_info($join); + $self->throw_exception("No such relationship ${join}") unless $rel_info; + my $type = $rel_info->{attrs}{join_type} || ''; + return [ { $as => $self->related_source($join)->from, + -join_type => $type }, + $self->resolve_condition($rel_info->{cond}, $as, $alias) ]; + } +} + +=head2 resolve_condition + +=head3 Arguments: ($cond, $as, $alias|$object) + +Resolves the passed condition to a concrete query fragment. If given an alias, +returns a join condition; if given an object, inverts that object to produce +a related conditional from that object. + +=cut + +sub resolve_condition { + my ($self, $cond, $as, $for) = @_; + #warn %$cond; + if (ref $cond eq 'HASH') { + my %ret; + while (my ($k, $v) = each %{$cond}) { + # XXX should probably check these are valid columns + $k =~ s/^foreign\.// || $self->throw_exception("Invalid rel cond key ${k}"); + $v =~ s/^self\.// || $self->throw_exception("Invalid rel cond val ${v}"); + if (ref $for) { # Object + #warn "$self $k $for $v"; + $ret{$k} = $for->get_column($v); + #warn %ret; + } elsif (ref $as) { # reverse object + $ret{$v} = $as->get_column($k); + } else { + $ret{"${as}.${k}"} = "${for}.${v}"; + } + } + return \%ret; + } elsif (ref $cond eq 'ARRAY') { + return [ map { $self->resolve_condition($_, $as, $for) } @$cond ]; + } else { + die("Can't handle this yet :("); + } +} + +=head2 resolve_prefetch + +=head3 Arguments: (hashref/arrayref/scalar) + +Accepts one or more relationships for the current source and returns an +array of column names for each of those relationships. Column names are +prefixed relative to the current source, in accordance with where they appear +in the supplied relationships. Examples: + + my $source = $schema->resultset('Tag')->source; + @columns = $source->resolve_prefetch( { cd => 'artist' } ); + + # @columns = + #( + # 'cd.cdid', + # 'cd.artist', + # 'cd.title', + # 'cd.year', + # 'cd.artist.artistid', + # 'cd.artist.name' + #) + + @columns = $source->resolve_prefetch( qw[/ cd /] ); + + # @columns = + #( + # 'cd.cdid', + # 'cd.artist', + # 'cd.title', + # 'cd.year' + #) + + $source = $schema->resultset('CD')->source; + @columns = $source->resolve_prefetch( qw[/ artist producer /] ); + + # @columns = + #( + # 'artist.artistid', + # 'artist.name', + # 'producer.producerid', + # 'producer.name' + #) + +=cut + +sub resolve_prefetch { + my ($self, $pre, $alias, $seen, $order, $collapse) = @_; + $seen ||= {}; + #$alias ||= $self->name; + #warn $alias, Dumper $pre; + if( ref $pre eq 'ARRAY' ) { + return + map { $self->resolve_prefetch( $_, $alias, $seen, $order, $collapse ) } + @$pre; + } + elsif( ref $pre eq 'HASH' ) { + my @ret = + map { + $self->resolve_prefetch($_, $alias, $seen, $order, $collapse), + $self->related_source($_)->resolve_prefetch( + $pre->{$_}, "${alias}.$_", $seen, $order, $collapse) + } keys %$pre; + #die Dumper \@ret; + return @ret; + } + elsif( ref $pre ) { + $self->throw_exception( + "don't know how to resolve prefetch reftype ".ref($pre)); + } + else { + my $count = ++$seen->{$pre}; + my $as = ($count > 1 ? "${pre}_${count}" : $pre); + my $rel_info = $self->relationship_info( $pre ); + $self->throw_exception( $self->name . " has no such relationship '$pre'" ) + unless $rel_info; + my $as_prefix = ($alias =~ /^.*?\.(.+)$/ ? $1.'.' : ''); + my $rel_source = $self->related_source($pre); + + if (exists $rel_info->{attrs}{accessor} + && $rel_info->{attrs}{accessor} eq 'multi') { + $self->throw_exception( + "Can't prefetch has_many ${pre} (join cond too complex)") + unless ref($rel_info->{cond}) eq 'HASH'; + my @key = map { (/^foreign\.(.+)$/ ? ($1) : ()); } + keys %{$rel_info->{cond}}; + $collapse->{"${as_prefix}${pre}"} = \@key; + my @ord = (ref($rel_info->{attrs}{order_by}) eq 'ARRAY' + ? @{$rel_info->{attrs}{order_by}} + : (defined $rel_info->{attrs}{order_by} + ? ($rel_info->{attrs}{order_by}) + : ())); + push(@$order, map { "${as}.$_" } (@key, @ord)); + } + + return map { [ "${as}.$_", "${as_prefix}${pre}.$_", ] } + $rel_source->columns; + #warn $alias, Dumper (\@ret); + #return @ret; + } +} + +=head2 related_source + +=head3 Arguments: ($relname) + +Returns the result source object for the given relationship + +=cut + +sub related_source { + my ($self, $rel) = @_; + if( !$self->has_relationship( $rel ) ) { + $self->throw_exception("No such relationship '$rel'"); + } + return $self->schema->source($self->relationship_info($rel)->{source}); +} + +=head2 resultset + +Returns a resultset for the given source, by calling: + + $self->resultset_class->new($self, $self->resultset_attributes) + +=head2 resultset_class + +Set the class of the resultset, this is useful if you want to create your +own resultset methods. Create your own class derived from +L, and set it here. + +=head2 resultset_attributes + +Specify here any attributes you wish to pass to your specialised resultset. + +=cut + +sub resultset { + my $self = shift; + $self->throw_exception('resultset does not take any arguments. If you want another resultset, call it on the schema instead.') if scalar @_; + return $self->{_resultset} if ref $self->{_resultset} eq $self->resultset_class; + return $self->{_resultset} = $self->resultset_class->new($self, $self->{resultset_attributes}); +} + +=head2 throw_exception + +See throw_exception in L. + +=cut + +sub throw_exception { + my $self = shift; + if (defined $self->schema) { + $self->schema->throw_exception(@_); + } else { + croak(@_); + } +} + =head1 AUTHORS