Dancer::Plugin::DBIC - DBIx::Class interface for Dancer applications
version 0.2104
use Dancer;
use Dancer::Plugin::DBIC qw(schema resultset rset);
get '/users/:user_id' => sub {
my $user_id = param 'user_id';
my $user;
# all of the following are equivalent:
$user = schema('default')->resultset('User')->find($user_id);
$user = schema->resultset('User')->find($user_id);
$user = resultset('User')->find($user_id);
$user = rset('User')->find($user_id);
template user_profile => {
user => $user
};
};
dance;
This plugin makes it very easy to create Dancer applications that interface
with databases.
It automatically exports the keyword schema
which returns a
DBIx::Class::Schema object.
You just need to configure your database connection information.
For performance, schema objects are cached in memory
and are lazy loaded the first time they are accessed.
This plugin is now just a thin wrapper around DBICx::Sugar.
Configuration can be done in your Dancer config file.
Here is a simple example. It defines one database named default
:
plugins:
DBIC:
default:
dsn: dbi:SQLite:dbname=myapp.db
schema_class: MyApp::Schema
In this example, there are 2 databases configured named default
and foo
:
plugins:
DBIC:
default:
dsn: dbi:SQLite:dbname=myapp.db
schema_class: MyApp::Schema
foo:
dsn: dbi:Pg:dbname=foo
schema_class: Foo::Schema
user: bob
password: secret
options:
RaiseError: 1
PrintError: 1
Each database configured must at least have a dsn option. The dsn option should be the DBI driver connection string. All other options are optional.
If you only have one schema configured, or one of them is named
default
, you can call schema
without an argument to get the only
or default
schema, respectively.
If a schema_class option is not provided, then DBIx::Class::Schema::Loader will be used to dynamically load the schema by introspecting the database corresponding to the dsn value. You need DBIx::Class::Schema::Loader installed for this to work.
WARNING: Dynamic loading is not recommended for production environments. It is almost always better to provide a schema_class option.
The schema_class option should be the name of your DBIx::Class::Schema class.
See "SCHEMA GENERATION"
Optionally, a database configuration may have user, password, and options
parameters as described in the documentation for connect()
in DBI.
Alternatively, you may also declare your connection information inside an
array named connect_info
:
plugins:
DBIC:
default:
schema_class: MyApp::Schema
connect_info:
- dbi:Pg:dbname=foo
- bob
- secret
-
RaiseError: 1
PrintError: 1
You can also add database read slaves to your configuration with the
replicated
config option.
This will automatically make your read queries go to a slave and your write
queries go to the master.
Keep in mind that this will require additional dependencies:
DBIx::Class::Optional::Dependencies#Storage::Replicated
See DBIx::Class::Storage::DBI::Replicated for more details.
Here is an example configuration that adds two read slaves:
plugins:
DBIC:
default:
schema_class: MyApp::Schema
dsn: dbi:Pg:dbname=master
replicated:
balancer_type: ::Random # optional
balancer_args: # optional
auto_validate_every: 5 # optional
master_read_weight:1 # optional
# pool_type and pool_args are also allowed and are also optional
replicants:
-
- dbi:Pg:dbname=slave1
- user1
- password1
-
quote_names: 1
pg_enable_utf8: 1
-
- dbi:Pg:dbname=slave2
- user2
- password2
-
quote_names: 1
pg_enable_utf8: 1
Schema aliases allow you to reference the same underlying database by multiple names. For example:
plugins:
DBIC:
default:
dsn: dbi:Pg:dbname=master
schema_class: MyApp::Schema
slave1:
alias: default
Now you can access the default schema with schema()
, schema('default')
,
or schema('slave1')
.
This can come in handy if, for example, you have master/slave replication in
your production environment but only a single database in your development
environment.
You can continue to reference schema('slave1')
in your code in both
environments by simply creating a schema alias in your development.yml config
file, as shown above.
my $user = schema->resultset('User')->find('bob');
The schema
keyword returns a DBIx::Class::Schema object ready for you to
use.
If you have configured only one database, then you can simply call schema
with no arguments.
If you have configured multiple databases,
you can still call schema
with no arguments if there is a database
named default
in the configuration.
With no argument, the default
schema is returned.
Otherwise, you must provide schema()
with the name of the database:
my $user = schema('foo')->resultset('User')->find('bob');
This is a convenience method that will save you some typing.
Use this only when accessing the default
schema.
my $user = resultset('User')->find('bob');
is equivalent to:
my $user = schema->resultset('User')->find('bob');
my $user = rset('User')->find('bob');
This is simply an alias for resultset
.
Setting the schema_class option and having proper DBIx::Class classes is the recommended approach for performance and stability. You can use the dbicdump command line tool provided by DBIx::Class::Schema::Loader to help you. For example, if your app were named Foo, then you could run the following from the root of your project directory:
dbicdump -o dump_directory=./lib Foo::Schema dbi:SQLite:/path/to/foo.db
For this example, your schema_class
setting would be 'Foo::Schema'
.
- Alexis Sukrieh sukria@sukria.net
- Dagfinn Ilmari Mannsåker <https://github.com/ilmari>
- David Precious davidp@preshweb.co.uk
- Fabrice Gabolde <https://github.com/fgabolde>
- Franck Cuny franck@lumberjaph.net
- Steven Humphrey <https://github.com/shumphrey>
- Yanick Champoux <https://github.com/yanick>
- Al Newkirk awncorp@cpan.org
- Naveed Massjouni naveed@vt.edu
This software is copyright (c) 2010 by awncorp.
This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.