1 package DBIx::Class::Schema::Loader;
5 use base qw/DBIx::Class::Schema/;
6 use base qw/Class::Data::Accessor/;
7 use Carp::Clan qw/^DBIx::Class::Schema::Loader/;
8 use UNIVERSAL::require;
10 use Scalar::Util qw/ weaken /;
12 # Always remember to do all digits for the version even if they're 0
13 # i.e. first release of 0.XX *must* be 0.XX000. This avoids fBSD ports
14 # brain damage and presumably various other packaging systems too
15 our $VERSION = '0.03004';
17 __PACKAGE__->mk_classaccessor('dump_to_dir');
18 __PACKAGE__->mk_classaccessor('loader');
19 __PACKAGE__->mk_classaccessor('_loader_args');
23 DBIx::Class::Schema::Loader - Dynamic definition of a DBIx::Class::Schema
28 use base qw/DBIx::Class::Schema::Loader/;
30 __PACKAGE__->loader_options(
32 constraint => '^foo.*',
36 # in seperate application code ...
40 my $schema1 = My::Schema->connect( $dsn, $user, $password, $attrs);
42 my $schema1 = "My::Schema"; $schema1->connection(as above);
46 DBIx::Class::Schema::Loader automates the definition of a
47 L<DBIx::Class::Schema> by scanning database table definitions and
48 setting up the columns, primary keys, and relationships.
50 DBIx::Class::Schema::Loader currently supports only the DBI storage type.
51 It has explicit support for L<DBD::Pg>, L<DBD::mysql>, L<DBD::DB2>, and
52 L<DBD::SQLite>. Other DBI drivers may function to a greater or lesser
53 degree with this loader, depending on how much of the DBI spec they
54 implement, and how standard their implementation is. Patches to make
55 other DBDs work correctly welcome.
57 See L<DBIx::Class::Schema::Loader::DBI::Writing> for notes on writing
58 your own vendor-specific subclass for an unsupported DBD driver.
60 This module requires L<DBIx::Class> 0.06 or later, and obsoletes
61 the older L<DBIx::Class::Loader>.
63 This module is designed more to get you up and running quickly against
64 an existing database, or to be effective for simple situations, rather
65 than to be what you use in the long term for a complex database/project.
67 That being said, transitioning your code from a Schema generated by this
68 module to one that doesn't use this module should be straightforward and
69 painless (as long as you're not using any methods that are now deprecated
70 in this document), so don't shy away from it just for fears of the
71 transition down the road.
77 Example in Synopsis above demonstrates a few common arguments. For
78 detailed information on all of the arguments, most of which are
79 only useful in fairly complex scenarios, see the
80 L<DBIx::Class::Schema::Loader::Base> documentation.
82 This method is *required* at this time, for backwards compatibility
83 reasons. If you do not wish to change any options, just call it
84 with an empty argument list during schema class initialization.
86 You should either specify this method before setting the connection
87 information for your schema, or specify these options as a part of
88 your connection information (see below). For now it will merely
89 warn if the ordering is wrong, but in the future this will cause problems.
96 my %args = (ref $_[0] eq 'HASH') ? %{$_[0]} : @_;
98 my $class = ref $self || $self;
99 $args{schema} = $self;
100 $args{schema_class} = $class;
101 weaken($args{schema}) if ref $self;
103 $self->_loader_args(\%args);
104 if($self->storage && !$class->loader) {
105 warn "Do not set loader_options after specifying the connection info";
106 $self->_invoke_loader;
114 my $class = ref $self || $self;
116 $self->_loader_args->{dump_directory} ||= $self->dump_to_dir;
118 # XXX this only works for relative storage_type, like ::DBI ...
119 my $impl = "DBIx::Class::Schema::Loader" . $self->storage_type;
121 croak qq/Could not load storage_type loader "$impl": / .
122 qq/"$UNIVERSAL::require::ERROR"/;
124 # XXX in the future when we get rid of ->loader, the next two
125 # lines can be replaced by "$impl->new(%{$self->_loader_args})->load;"
126 $class->loader($impl->new(%{$self->_loader_args}));
127 $class->loader->load;
134 See L<DBIx::Class::Schema> for basic usage.
136 If the final argument is a hashref, and it contains a key C<loader_options>,
137 that key will be deleted, and its value will be used for the loader options,
138 just as if set via the L</loader_options> method above.
140 The actual auto-loading operation (the heart of this module) will be invoked
141 as soon as the connection information is defined.
148 if($_[-1] && ref $_[-1] eq 'HASH') {
149 if(my $loader_opts = delete $_[-1]->{loader_options}) {
150 $self->loader_options($loader_opts);
154 $self = $self->next::method(@_);
156 my $class = ref $self || $self;
157 $self->_invoke_loader if $self->_loader_args && !$class->loader;
164 See L<DBIx::Class::Schema>.
171 croak "You failed to specify the required loader_options"
172 if !$self->_loader_args;
174 my $clone = $self->next::method(@_);
176 $clone->_loader_args($self->_loader_args);
177 $clone->_loader_args->{schema} = $clone;
178 weaken($clone->_loader_args->{schema});
185 Argument: directory name.
187 Calling this as a class method on either L<DBIx::Class::Schema::Loader>
188 or any derived schema class will cause all affected schemas to dump
189 manual versions of themselves to the named directory when they are
190 loaded. In order to be effective, this must be set before defining a
191 connection on this schema class or any derived object (as the loading
192 happens as soon as both a connection and loader_options are set, and
193 only once per class).
195 See L<DBIx::Class::Schema::Loader::Base/dump_directory> for more
196 details on the dumping mechanism.
198 This can also be set at module import time via the import option
199 C<dump_to_dir:/foo/bar> to L<DBIx::Class::Schema::Loader>, where
200 C</foo/bar> is the target directory.
204 # My::Schema isa DBIx::Class::Schema::Loader, and has connection info
205 # hardcoded in the class itself:
206 perl -MDBIx::Class::Schema::Loader=dump_to_dir:/foo/bar -MMy::Schema -e1
208 # Same, but no hard-coded connection, so we must provide one:
209 perl -MDBIx::Class::Schema::Loader=dump_to_dir:/foo/bar -MMy::Schema -e 'My::Schema->connection("dbi:Pg:dbname=foo", ...)'
211 # Or as a class method, as long as you get it done *before* defining a
212 # connection on this schema class or any derived object:
214 My::Schema->dump_to_dir('/foo/bar');
215 My::Schema->connection(........);
217 # Or as a class method on the DBIx::Class::Schema::Loader itself, which affects all
221 DBIx::Class::Schema::Loader->dump_to_dir('/foo/bar');
222 My::Schema->connection(.......);
223 My::OtherSchema->connection(.......);
225 # Another alternative to the above:
226 use DBIx::Class::Schema::Loader qw| dump_to_dir:/foo/bar |;
229 My::Schema->connection(.......);
230 My::OtherSchema->connection(.......);
237 foreach my $opt (@_) {
238 if($opt =~ m{^dump_to_dir:(.*)$}) {
239 $self->dump_to_dir($1)
241 elsif($opt eq 'make_schema_at') {
243 my $cpkg = (caller)[0];
244 *{"${cpkg}::make_schema_at"} = \&make_schema_at;
249 =head2 make_schema_at
251 This simple function allows one to create a Loader-based schema
252 in-memory on the fly without any on-disk class files of any
253 kind. When used with the C<dump_directory> option, you can
254 use this to generate a rough draft manual schema from a dsn
255 without the intermediate step of creating a physical Loader-based
258 The return value is the input class name.
260 This function can be exported/imported by the normal means, as
261 illustrated in these Examples:
263 # Simple example, creates as a new class 'New::Schema::Name' in
264 # memory in the running perl interpreter.
265 use DBIx::Class::Schema::Loader qw/ make_schema_at /;
268 { relationships => 1, debug => 1 },
269 [ 'dbi:Pg:dbname="foo"','postgres' ],
272 # Complex: dump loaded schema to disk, all from the commandline:
273 perl -MDBIx::Class::Schema::Loader=make_schema_at,dump_to_dir:./lib -e 'make_schema_at("New::Schema::Name", { relationships => 1 }, [ "dbi:Pg:dbname=foo","postgres" ])'
275 # Same, but inside a script, and using a different way to specify the
277 use DBIx::Class::Schema::Loader qw/ make_schema_at /;
280 { relationships => 1, debug => 1, dump_directory => './lib' },
281 [ 'dbi:Pg:dbname="foo"','postgres' ],
287 my ($target, $opts, $connect_info) = @_;
291 @{$target . '::ISA'} = qw/DBIx::Class::Schema::Loader/;
294 $target->loader_options($opts);
295 $target->connection(@$connect_info);
300 Using the example in L<DBIx::Class::Manual::ExampleSchema> as a basis
301 replace the DB::Main with the following code:
305 use base qw/DBIx::Class::Schema::Loader/;
307 __PACKAGE__->loader_options(
311 __PACKAGE__->connection('dbi:SQLite:example.db');
315 and remove the Main directory tree (optional). Every thing else
318 =head1 DEPRECATED METHODS
320 You don't need to read anything in this section unless you're upgrading
321 code that was written against pre-0.03 versions of this module. This
322 version is intended to be backwards-compatible with pre-0.03 code, but
323 will issue warnings about your usage of deprecated features/methods.
325 B<All of these deprecated methods will dissappear in version 0.04000>,
326 and converting code that uses these methods should be trivial.
328 =head2 load_from_connection
330 This deprecated method is now roughly an alias for L</loader_options>.
332 For now, using this method will invoke the legacy behavior for
333 backwards compatibility, and merely emit a warning about upgrading
336 It also reverts the default inflection scheme to
337 use L<Lingua::EN::Inflect> just like pre-0.03 versions of this
340 You can force these legacy inflections with the
341 option L<DBIx::Class::Schema::Loader::Base/legacy_default_inflections>,
342 even after switch over to the preferred L</loader_options> way of doing
343 things. That option will not go away until at least 0.05.
345 See the source of this method for more details.
349 sub load_from_connection {
350 my ($self, %args) = @_;
352 my $cmds_ver = $Catalyst::Model::DBIC::Schema::VERSION;
354 if($cmds_ver < 0.14) {
355 warn 'You should upgrade your installation of'
356 . ' Catalyst::Model::DBIC::Schema to 0.14 or higher, then:';
358 warn 'You should regenerate your Model files, which may eliminate'
359 . ' the following deprecation warning:';
361 warn 'load_from_connection deprecated, and will dissappear in 0.04000, '
362 . 'please [re-]read the [new] DBIx::Class::Schema::Loader '
365 # Support the old connect_info / dsn / etc args...
366 $args{connect_info} = [
369 delete $args{password},
370 delete $args{options},
373 $self->connection(@{delete $args{connect_info}})
374 if $args{connect_info};
376 $self->loader_options('legacy_default_inflections' => 1, %args);
381 This is an accessor in the generated Schema class for accessing
382 the L<DBIx::Class::Schema::Loader::Base> -based loader object
383 that was used during construction. See the
384 L<DBIx::Class::Schema::Loader::Base> docs for more information
385 on the available loader methods there.
387 This accessor is deprecated. Do not use it. Anything you can
388 get from C<loader>, you can get via the normal L<DBIx::Class::Schema>
389 methods, and your code will be more robust and forward-thinking
392 If you're already using C<loader> in your code, make an effort
393 to get rid of it. If you think you've found a situation where it
394 is necessary, let me know and we'll see what we can do to remedy
397 In some future version, this accessor *will* disappear. It was
398 apparently quite a design/API mistake to ever have exposed it to
399 user-land in the first place, all things considered.
403 =head2 Multiple Database Schemas
405 Currently the loader is limited to working within a single schema
406 (using the database vendors' definition of "schema"). If you
407 have a multi-schema database with inter-schema relationships (which
408 is easy to do in PostgreSQL or DB2 for instance), you only get to
409 automatically load the tables of one schema, and any relationships
410 to tables in other schemas will be silently ignored.
412 At some point in the future, an intelligent way around this might be
413 devised, probably by allowing the C<db_schema> option to be an
414 arrayref of schemas to load.
416 In "normal" L<DBIx::Class::Schema> usage, manually-defined
417 source classes and relationships have no problems crossing vendor schemas.
421 Brandon Black, C<blblack@gmail.com>
423 Based on L<DBIx::Class::Loader> by Sebastian Riedel
425 Based upon the work of IKEBE Tomohiro
429 Matt S Trout, all of the #dbix-class folks, and everyone who's ever sent
430 in a bug report or suggestion.
434 This library is free software; you can redistribute it and/or modify it under
435 the same terms as Perl itself.
439 L<DBIx::Class>, L<DBIx::Class::Manual::ExampleSchema>