NAME
DBIx::Class::Migration::Script - Tools to manage database Migrations
SYNOPSIS
dbic-migration status \
--lib="lib" \
--schema_class='MyApp::Schema' \
--dsn='DBI:SQLite:myapp.db'
DESCRIPTION
This is a class which provides an interface mapping between the commandline script dbic-migration and the back end code that does the heavy lifting, DBIx::Class::Migration. This class has very little of it's own functionality, since it basically acts as processing glue between that commandline application and the code which does all the work.
You should look at DBIx::Class::Migration and the tutorial over at DBIx::Class::Migration::Tutorial to get started. This is basically API level docs and a command summary which is likely to be useful as a reference when you are familiar with the system.
ATTRIBUTES
This class defines the following attributes.
migration
This contains an instance of DBIx::Class::Migration which is constructed from various attributes described futher in these docs.
This is basically a delegate for all the commands you perform with this interface.
includes
Accepts ArrayRef. Not required.
Similar to the commandline switch I
for the perl
interpreter. It adds to @INC
for when we want to search for modules to load. This is primarily useful for specifying a path to find a "schema_class".
We make no attempt to check the validity of any paths specified. Buyer beware.
schema_class
Accepts Str. Required.
This is the schema we use as the basic for creating, managing and running your deployments. This should be the full package namespace defining your subclass of DBIx::Class::Schema. For example MyApp::Schema
.
Uses MooX::Attribute::ENV to let you populate values from %ENV. Uses key DBIC_MIGRATION_SCHEMA_CLASS
If the "schema_class" cannot be loaded, a hard exception will be thrown.
target_dir
Accepts Str. Required.
This is the directory we store our migration and fixture files. Inside this directory we will create a fixtures
and migrations
sub-directory.
Although you can specify the directory, if you leave it undefined, we will use File::ShareDir::ProjectDistDir to locate the share
directory for your project and place the files there. This is the recommended approach, and is considered a community practice in regards to where to store your distribution non code files. Please see File::ShareDir::ProjectDistDir as well as File::ShareDir for more information.
Uses MooX::Attribute::ENV to let you populate values from %ENV. Uses key DBIC_MIGRATION_TARGET_DIR
sandbox_dir
Accepts Str. Optional
Used if you wish to build the sandbox (if you are building one) in a location that is not the 'target_dir'. For example you might do this to make it easier to not accidentally check the sandbox into the repository or if you are reusing it across several projects.
username
Accepts Str. Not Required
This should be the username for the database we connect to for deploying ddl, ddl changes and fixtures.
Uses MooX::Attribute::ENV to let you populate values from %ENV. Uses key DBIC_MIGRATION_USERNAME
password
Accepts Str. Not Required
This should be the password for the database we connect to for deploying ddl, ddl changes and fixtures.
Uses MooX::Attribute::ENV to let you populate values from %ENV. Uses key DBIC_MIGRATION_PASSWORD
dsn
Accepts Str. Not Required
This is the DSN for the database you are going to be targeting for deploying or altering ddl, and installing or generating fixtures.
This should be a DSN suitable for "connect" in DBIx::Class::Schema, something in the form of DBI:SQLite:myapp-schema.db
.
Please take care where you point this (like production :) )
If you don't provide a value, we will automatically create a SQLite based database connection with the following DSN:
DBD:SQLite:[path to target_dir]/[db_file_name].db
Where c<[path to target_dir]> is "target_dir" and [db_file_name] is a converted version of "schema_class". For example if you set schema_class to:
MyApp::Schema
Then [db_file_name] would be myapp-schema
.
Please remember that you can generate deployment files for database types other than the one you've defined in "dsn", however since different databases enforce constraints differently it would not be impossible to generate fixtures that can be loaded by one database but not another. Therefore I recommend always generated fixtures from a database that is consistent across enviroments.
Uses MooX::Attribute::ENV to let you populate values from %ENV. Uses key DBIC_MIGRATION_DSN
force_overwrite
Accepts Bool. Not Required. Defaults to False.
Used when building "migration" to en / disable the DBIx::Class::DeploymentHandler option force_overwrite
. This is used when generating DDL and related files for a given version of your "_schema" to decide if it is ok to overwrite deployment files. You might need this if you deploy a version of the database during development and then need to make more changes or fixes for that version.
to_version
Accepts Int. Not Required.
Used to establish a target version when running an install. You can use this to force install a version of the database other then your current "_schema" version. You might want this when you need to force install a lower version as part of your development process for changing the database.
If you leave this undefined, no default value is built, however DBIx::Class::DeploymentHandler will assume you want whatever is the value of your $schema->version.
databases
Accepts ArrayRef. Not Required.
Used when building "migration" to define the target databases we are building migration files for. You can name any of the databases currently supported by SQL::Translator. If you leave this undefined we will derive a value based on the value of "dsn". For example, if your "dsn" is "DBI:SQLite:test.db", we will set the value of "databases" to ['SQLite']
.
sql_translator_args
Accepts HashRef. Not Required.
Used when building "migration" to set the DBIx::Class::DeploymentHandler option sql_translator_args
. This can be used to specify options for SQL::Translator, for example:
producer_args => { postgres_version => '9.1' }
to define the database version for SQL producer. Defaults to setting quote_identifiers
to a true value, which despite being documented as the default, is not the case in practice.
fixture_sets
Accepts ArrayRef. Not Required. Defaults to ['all_tables'].
This defines a list of fixture sets that we use for dumping or populating fixtures. Defaults to the ['all_tables']
set, which is the one set we build automatically for each version of the database we prepare deployments for.
sandbox_class
Accepts String. Not required. Defaults to 'SqliteSandbox'
If you don't have a database already running, we will automatically create a database 'sandbox' in your "target_dir" that is suitable for development and rapid prototyping. This is intended for developers and intended to make life more simple, particularly for beginners who might not have all the knowledged needed to setup a database for development purposes.
By default this sandbox is a file based DBD::Sqlite database, which is an easy option since changes are good this is already installed on your development computer (and if not it is trivial to install).
You can change this to either 'PostgresqlSandbox' or 'MySQLSandbox', which will create a sandbox using either DBIx::Class::Migration::MySQLSandbox or DBIx::Class::Migration::PostgresqlSandbox (which in term require the separate installation of either Test::mysqld or Test::Postgresql58). If you are using one of those open source databases in production, its probably a good idea to use them in development as well, since there are enough small differences between them that could make your code break if you used sqlite for development and postgresql in production. However this requires a bit more setup effort, so when you are starting off just sticking to the default sqlite is probably the easiest thing to do.
You should review the documenation at DBIx::Class::Migration::MySQLSandbox or DBIx::Class::Migration::PostgresqlSandbox because those delegates also build some helper scripts, intended to help you use a sandbox.
Uses MooX::Attribute::ENV to let you populate values from %ENV. Uses key DBIC_MIGRATION_SANDBOX_CLASS
If you need to create your own custom database sandboxes, please see: DBIx::Class::Migration::Sandbox which is the role your sandbox factory needs to complete. You can signify your custom sandbox by using the full package name with a '+' prepended. For example:
sandbox_class => '+MyApp::Schema::CustomSandbox'
You should probably look at the existing sandbox code for thoughts on what a good sandbox would do.
migration_class
Accepts String. Not Required (Defaults: DBIx::Class::Migration)
Should point to the class that does what DBIx::Class::Migration does. This is exposed here for those who need to subclass DBIx::Class::Migration. We don't expose this attribute to the commandline, so if you are smart enough to do the subclassing (and sure you need to do that), I will assume you will also either subclass DBIx::Class::Migration:Script or override then default value using some standard technique.
dbic_fixture_class
Accepts: Str, Not Required.
You can use this if you need to make a custom subclass of DBIx::Class::Fixtures.
dbic_fixtures_extra_args
Accepts: HashRef, Not Required.
If provided will add some additional arguments when creating an instance of "dbic_fixture_class". You should take a look at the documentation for DBIx::Class::Fixtures to understand what additional arguments may be of use.
dbi_connect_attrs
Accepts: HashRef, Not Required.
If you are specifying a DSN, you might need to provide some additional args to DBI (see "connect_info" in DBIx::Class::Storage::DBI for more).
dbic_connect_attrs
Accepts: HashRef, Not Required.
If you are specifying a DSN, you might need to provide some additional args to DBIx::Class (see "connect_info" in DBIx::Class::Storage::DBI for more).
You can also see "DBIx::Class-specific-connection-attributes" in DBIx::Class::Storage::DBI for more information on what this can do for you. Chances are good if you need this you will also want to subclass DBIx::Class::Migration::Script as well.
Common uses for this is to run SQL on startup and set Postgresql search paths.
extra_schemaloader_args
Accepts: HashRef, Not Required.
Used to populate "extra_schemaloader_args" in DBIx::Class::Migration
migration_sandbox_builder_class
Accepts: String (Classname), Not Required.
Used to set "db_sandbox_builder_class" in DBIx::Class::Migration. You probably won't mess with this unless you are writing your own Sandbox builder class, or using the alternative builder DBIx::Class::Migration::TempDirSandboxBuilder for creating temporary sandboxes when you want to test your migrations.
COMMANDS
dbic-migration -Ilib install
Since this class uses MooX::Options, it can be run directly as a commandline application. The following is a list of commands we support as well as the options / flags associated with each command.
help
See DBIx::Class::Migration::Script::Help::help.
version
See DBIx::Class::Migration::Script::Help::version.
status
See DBIx::Class::Migration::Script::Help::status.
prepare
See DBIx::Class::Migration::Script::Help::prepare.
install
See DBIx::Class::Migration::Script::Help::install.
upgrade
See DBIx::Class::Migration::Script::Help::upgrade.
downgrade
See DBIx::Class::Migration::Script::Help::downgrade.
dump_named_sets
See DBIx::Class::Migration::Script::Help::dump_named_sets.
dump_all_sets
See DBIx::Class::Migration::Script::Help::dump_all_sets.
populate
See DBIx::Class::Migration::Script::Help::populate.
drop_tables
See DBIx::Class::Migration::Script::Help::drop_tables.
delete_table_rows
See DBIx::Class::Migration::Script::Help::delete_table_rows.
make_schema
See DBIx::Class::Migration::Script::Help::make_schema.
install_if_needed
See DBIx::Class::Migration::Script::Help::install_if_needed.
install_version_storage
See DBIx::Class::Migration::Script::Help::install_version_storage.
diagram
See DBIx::Class::Migration::Script::Help::diagram.
delete_named_sets
See DBIx::Class::Migration::Script::Help::delete_named_sets.
Command Flags
The following flags are used to modify or inform commands.
includes
See DBIx::Class::Migration::Script::Help::includes.
schema_class
See DBIx::Class::Migration::Script::Help::schema_class.
target_dir
See DBIx::Class::Migration::Script::Help::target_dir.
username
Aliases: U Value: Str
password
Aliases: P Value: String
dsn
Value: String
These three commandline flags describe how to connect to a target, physical database, where we will deploy migrations and fixtures. If you don't provide them, we will automatically deploy to a DBD::SQLite managed database located at "target_dir".
dbic-migration install --username myuser --password mypass --dsn DBI:SQLite:mydb.db
force_overwrite
See DBIx::Class::Migration::Script::Help::force_overwrite
to_version
See DBIx::Class::Migration::Script::Help::to_version
databases
See DBIx::Class::Migration::Script::Help::databases
fixture_sets
See DBIx::Class::Migration::Script::Help::fixture_sets
sandbox_class
See DBIx::Class::Migration::Script::Help::sandbox_class
The default sqlite sandbox is documented at DBIx::Class::Migration::SQLiteSandbox although this single file database is pretty straightforward to use.
If you are declaring the value in a subclass, you can use the pre-defined constants to avoid typos (see "CONSTANTS").
dbic_fixture_class
See DBIx::Class::Migration::Script::Help::dbic_fixture_class
dbic_fixtures_extra_args
See DBIx::Class::Migration::Script::Help::dbic_fixtures_extra_args
dbic_connect_attrs
See DBIx::Class::Migration::Script::Help::dbic_connect_attrs
dbi_connect_attrs
See DBIx::Class::Migration::Script::Help::dbi_connect_attrs
extra_schemaloader_args
See DBIx::Class::Migration::Script::Help::extra_schemaloader_args
OPTIONAL METHODS FOR SUBCLASSES
If you decide to make a custom subclass of DBIx::Class::Migration::Script, (you might do this for example to better integrate your migrations with an existing framework, like Catalyst) you may defined the following option methods.
default
Returns a Hash of instantiation values.
Merges some predefined values when instantiating. For example:
package MusicBase::Schema::MigrationScript;
use Moose;
use MusicBase::Web;
extends 'DBIx::Class::Migration::Script';
sub defaults {
schema => MusicBase::Web->model('Schema')->schema,
}
__PACKAGE__->meta->make_immutable;
__PACKAGE__->run_if_script;
This would create a version of your script that already includes the target schema
. In this example we will let Catalyst configuration handle which database to run deployments against.
ADDITIONAL INFORMATION FOR SUBCLASSERS
The following methods are documented of interest to subclassers.
run_if_script
Class method that detects if your module is being called as a script. Place it at the end of your subclass:
__PACKAGE__->run_if_script;
This returns true in the case you are using the class as a module, and calls "run_with_options" otherwise. Adding this lets you invoke your class module as a script from the commandline (saving you the trouble of writing a thin script wrapper).
perl -Ilib lib/MyApp/Schema/MigrationScript.pm --status
run_with_options
Given a Hash of initial arguments, merges those with the results of values passed on the commandline (via MooX::Options) and run.
run
Actually runs commands.
CONSTANTS
The following constants are defined but not exported. These are used to give a canonical value for the "sandbox_class" attribute.
SANDBOX_SQLITE
SqliteSandbox
SANDBOX_MYSQL
MySQLSandbox
SANDBOX_POSTGRESQL
PostgresqlSandbox
EXAMPLES
Please see DBIx::Class::Migration::Tutorial for more. Here's some basic use cases.
Prepare deployment files for a schema
dbic-migration prepare --schema_class MyApp::Schema
This will prepare deployment files for just SQLite
dbic-migration prepare --database SQLite --database MySQL \
--schema_class MyApp::Schema
This will prepare deployment files for both SQLite and MySQL
Install database from deployments
dbic-migration install --schema_class MyApp::Schema
Creates the default sqlite database in the share
directory.
dbic-migration install --schema_class MyApp::Schema --to_version 2
Same as the previous command, but installs version 2, instead of whatever is the most recent version
dbic-migration populate --schema_class MyApp::Schema --fixture_set seed
Populates the seed
fixture set to the current database (matches the database version to the seed version.)
SEE ALSO
AUTHOR
See DBIx::Class::Migration for author information
COPYRIGHT & LICENSE
See DBIx::Class::Migration for copyright and license information