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/;
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 = '0.03010';
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 Setting these options explicitly via this method B<after> calling
87 C<connection> is deprecated and will stop working in version 0.04000.
88 For now the code merely warns about this condition.
90 The preferred way of doing things is to either call C<loader_options>
91 before any connection is made, or embed the C<loader_options> in
92 the connection information itself as shown below.
99 my %args = (ref $_[0] eq 'HASH') ? %{$_[0]} : @_;
101 my $class = ref $self || $self;
102 $args{schema} = $self;
103 $args{schema_class} = $class;
104 weaken($args{schema}) if ref $self;
106 $self->_loader_args(\%args);
107 if($self->storage && !$class->loader) {
108 warn "Do not set loader_options after specifying the connection info,"
109 . " this will be unsupported in 0.04000";
110 $self->_invoke_loader;
118 my $class = ref $self || $self;
120 $self->_loader_args->{dump_directory} ||= $self->dump_to_dir;
122 # XXX this only works for relative storage_type, like ::DBI ...
123 my $impl = "DBIx::Class::Schema::Loader" . $self->storage_type;
125 croak qq/Could not load storage_type loader "$impl": / .
126 qq/"$UNIVERSAL::require::ERROR"/;
128 # XXX in the future when we get rid of ->loader, the next two
129 # lines can be replaced by "$impl->new(%{$self->_loader_args})->load;"
130 $class->loader($impl->new(%{$self->_loader_args}));
131 $class->loader->load;
138 See L<DBIx::Class::Schema> for basic usage.
140 If the final argument is a hashref, and it contains a key C<loader_options>,
141 that key will be deleted, and its value will be used for the loader options,
142 just as if set via the L</loader_options> method above.
144 The actual auto-loading operation (the heart of this module) will be invoked
145 as soon as the connection information is defined.
152 if($_[-1] && ref $_[-1] eq 'HASH') {
153 if(my $loader_opts = delete $_[-1]->{loader_options}) {
154 $self->loader_options($loader_opts);
155 pop @_ if !keys %{$_[-1]};
159 $self = $self->next::method(@_);
161 my $class = ref $self || $self;
162 if($self->_loader_args && !$class->loader) {
163 $self->_invoke_loader
171 See L<DBIx::Class::Schema>.
178 my $clone = $self->next::method(@_);
180 if($clone->_loader_args) {
181 $clone->_loader_args->{schema} = $clone;
182 weaken($clone->_loader_args->{schema});
190 Argument: directory name.
192 Calling this as a class method on either L<DBIx::Class::Schema::Loader>
193 or any derived schema class will cause all affected schemas to dump
194 manual versions of themselves to the named directory when they are
195 loaded. In order to be effective, this must be set before defining a
196 connection on this schema class or any derived object (as the loading
197 happens as soon as both a connection and loader_options are set, and
198 only once per class).
200 See L<DBIx::Class::Schema::Loader::Base/dump_directory> for more
201 details on the dumping mechanism.
203 This can also be set at module import time via the import option
204 C<dump_to_dir:/foo/bar> to L<DBIx::Class::Schema::Loader>, where
205 C</foo/bar> is the target directory.
209 # My::Schema isa DBIx::Class::Schema::Loader, and has connection info
210 # hardcoded in the class itself:
211 perl -MDBIx::Class::Schema::Loader=dump_to_dir:/foo/bar -MMy::Schema -e1
213 # Same, but no hard-coded connection, so we must provide one:
214 perl -MDBIx::Class::Schema::Loader=dump_to_dir:/foo/bar -MMy::Schema -e 'My::Schema->connection("dbi:Pg:dbname=foo", ...)'
216 # Or as a class method, as long as you get it done *before* defining a
217 # connection on this schema class or any derived object:
219 My::Schema->dump_to_dir('/foo/bar');
220 My::Schema->connection(........);
222 # Or as a class method on the DBIx::Class::Schema::Loader itself, which affects all
226 DBIx::Class::Schema::Loader->dump_to_dir('/foo/bar');
227 My::Schema->connection(.......);
228 My::OtherSchema->connection(.......);
230 # Another alternative to the above:
231 use DBIx::Class::Schema::Loader qw| dump_to_dir:/foo/bar |;
234 My::Schema->connection(.......);
235 My::OtherSchema->connection(.......);
242 foreach my $opt (@_) {
243 if($opt =~ m{^dump_to_dir:(.*)$}) {
244 $self->dump_to_dir($1)
246 elsif($opt eq 'make_schema_at') {
248 my $cpkg = (caller)[0];
249 *{"${cpkg}::make_schema_at"} = \&make_schema_at;
254 =head2 make_schema_at
256 This simple function allows one to create a Loader-based schema
257 in-memory on the fly without any on-disk class files of any
258 kind. When used with the C<dump_directory> option, you can
259 use this to generate a rough draft manual schema from a dsn
260 without the intermediate step of creating a physical Loader-based
263 The return value is the input class name.
265 This function can be exported/imported by the normal means, as
266 illustrated in these Examples:
268 # Simple example, creates as a new class 'New::Schema::Name' in
269 # memory in the running perl interpreter.
270 use DBIx::Class::Schema::Loader qw/ make_schema_at /;
273 { relationships => 1, debug => 1 },
274 [ 'dbi:Pg:dbname="foo"','postgres' ],
277 # Complex: dump loaded schema to disk, all from the commandline:
278 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" ])'
280 # Same, but inside a script, and using a different way to specify the
282 use DBIx::Class::Schema::Loader qw/ make_schema_at /;
285 { relationships => 1, debug => 1, dump_directory => './lib' },
286 [ 'dbi:Pg:dbname="foo"','postgres' ],
292 my ($target, $opts, $connect_info) = @_;
296 @{$target . '::ISA'} = qw/DBIx::Class::Schema::Loader/;
299 $target->loader_options($opts);
300 $target->connection(@$connect_info);
305 Using the example in L<DBIx::Class::Manual::ExampleSchema> as a basis
306 replace the DB::Main with the following code:
310 use base qw/DBIx::Class::Schema::Loader/;
312 __PACKAGE__->loader_options(
316 __PACKAGE__->connection('dbi:SQLite:example.db');
320 and remove the Main directory tree (optional). Every thing else
323 =head1 DEPRECATED METHODS
325 You don't need to read anything in this section unless you're upgrading
326 code that was written against pre-0.03 versions of this module. This
327 version is intended to be backwards-compatible with pre-0.03 code, but
328 will issue warnings about your usage of deprecated features/methods.
330 B<All of these deprecated methods will dissappear in version 0.04000>,
331 and converting code that uses these methods should be trivial.
333 =head2 load_from_connection
335 This deprecated method is now roughly an alias for L</loader_options>.
337 For now, using this method will invoke the legacy behavior for
338 backwards compatibility, and merely emit a warning about upgrading
341 It also reverts the default inflection scheme to
342 use L<Lingua::EN::Inflect> just like pre-0.03 versions of this
345 You can force these legacy inflections with the
346 option L<DBIx::Class::Schema::Loader::Base/legacy_default_inflections>,
347 even after switch over to the preferred L</loader_options> way of doing
348 things. That option will not go away until at least 0.05.
350 See the source of this method for more details.
354 sub load_from_connection {
355 my ($self, %args) = @_;
357 my $cmds_ver = $Catalyst::Model::DBIC::Schema::VERSION;
359 if($cmds_ver < 0.14) {
360 warn 'You should upgrade your installation of'
361 . ' Catalyst::Model::DBIC::Schema to 0.14 or higher, then:';
363 warn 'You should regenerate your Model files, which may eliminate'
364 . ' the following deprecation warning:';
366 warn 'load_from_connection deprecated, and will dissappear in 0.04000, '
367 . 'please [re-]read the [new] DBIx::Class::Schema::Loader '
370 # Support the old connect_info / dsn / etc args...
371 $args{connect_info} = [
374 delete $args{password},
375 delete $args{options},
378 $self->connection(@{delete $args{connect_info}})
379 if $args{connect_info};
381 $self->loader_options('legacy_default_inflections' => 1, %args);
386 This is an accessor in the generated Schema class for accessing
387 the L<DBIx::Class::Schema::Loader::Base> -based loader object
388 that was used during construction. See the
389 L<DBIx::Class::Schema::Loader::Base> docs for more information
390 on the available loader methods there.
392 This accessor is deprecated. Do not use it. Anything you can
393 get from C<loader>, you can get via the normal L<DBIx::Class::Schema>
394 methods, and your code will be more robust and forward-thinking
397 If you're already using C<loader> in your code, make an effort
398 to get rid of it. If you think you've found a situation where it
399 is necessary, let me know and we'll see what we can do to remedy
402 In some future version, this accessor *will* disappear. It was
403 apparently quite a design/API mistake to ever have exposed it to
404 user-land in the first place, all things considered.
408 =head2 Multiple Database Schemas
410 Currently the loader is limited to working within a single schema
411 (using the database vendors' definition of "schema"). If you
412 have a multi-schema database with inter-schema relationships (which
413 is easy to do in PostgreSQL or DB2 for instance), you only get to
414 automatically load the tables of one schema, and any relationships
415 to tables in other schemas will be silently ignored.
417 At some point in the future, an intelligent way around this might be
418 devised, probably by allowing the C<db_schema> option to be an
419 arrayref of schemas to load.
421 In "normal" L<DBIx::Class::Schema> usage, manually-defined
422 source classes and relationships have no problems crossing vendor schemas.
426 Brandon Black, C<blblack@gmail.com>
428 Based on L<DBIx::Class::Loader> by Sebastian Riedel
430 Based upon the work of IKEBE Tomohiro
434 Matt S Trout, all of the #dbix-class folks, and everyone who's ever sent
435 in a bug report or suggestion.
439 This library is free software; you can redistribute it and/or modify it under
440 the same terms as Perl itself.
444 L<DBIx::Class>, L<DBIx::Class::Manual::ExampleSchema>