/ 
DBIx-Class-DeploymentHandler-0.001000_09
River stage two • 12 direct dependents • 12 total dependents
/ DBIx::Class::DeploymentHandler::DeployMethod::SQL::Translator

NAME

DBIx::Class::DeploymentHandler::DeployMethod::SQL::Translator - Manage your SQL and Perl migrations in nicely laid out directories

DESCRIPTION

This class is the meat of DBIx::Class::DeploymentHandler. It takes care of generating sql files representing schemata as well as sql files to move from one version of a schema to the rest. One of the hallmark features of this class is that it allows for multiple sql files for deploy and upgrade, allowing developers to fine tune deployment. In addition it also allows for perl files to be run at any stage of the process.

For basic usage see DBIx::Class::DeploymentHandler::HandlesDeploy. What's documented here is extra fun stuff or private methods.

DIRECTORY LAYOUT

Arguably this is the best feature of DBIx::Class::DeploymentHandler. It's heavily based upon DBIx::Migration::Directories, but has some extensions and modifications, so even if you are familiar with it, please read this. I feel like the best way to describe the layout is with the following example:

$sql_migration_dir
|- SQLite
|  |- down
|  |  `- 2-1
|  |     `- 001-auto.sql
|  |- schema
|  |  `- 1
|  |     `- 001-auto.sql
|  `- up
|     |- 1-2
|     |  `- 001-auto.sql
|     `- 2-3
|        `- 001-auto.sql
|- _common
|  |- down
|  |  `- 2-1
|  |     `- 002-remove-customers.pl
|  `- up
|     `- 1-2
|        `- 002-generate-customers.pl
|- _generic
|  |- down
|  |  `- 2-1
|  |     `- 001-auto.sql
|  |- schema
|  |  `- 1
|  |     `- 001-auto.sql
|  `- up
|     `- 1-2
|        |- 001-auto.sql
|        `- 002-create-stored-procedures.sql
`- MySQL
   |- down
   |  `- 2-1
   |     `- 001-auto.sql
   |- preinstall
   |  `- 1
   |     |- 001-create_database.pl
   |     `- 002-create_users_and_permissions.pl
   |- schema
   |  `- 1
   |     `- 001-auto.sql
   `- up
      `- 1-2
         `- 001-auto.sql

So basically, the code

$dm->deploy(1)

on an SQLite database that would simply run $sql_migration_dir/SQLite/schema/1/001-auto.sql. Next,

$dm->upgrade_single_step([1,2])

would run $sql_migration_dir/SQLite/up/1-2/001-auto.sql followed by $sql_migration_dir/_common/up/1-2/002-generate-customers.pl.

Now, a .pl file doesn't have to be in the _common directory, but most of the time it probably should be, since perl scripts will mostly be database independent.

_generic exists for when you for some reason are sure that your SQL is generic enough to run on all databases. Good luck with that one.

Note that unlike most steps in the process, preinstall will not run SQL, as there may not even be an database at preinstall time. It will run perl scripts just like the other steps in the process, but nothing is passed to them. Until people have used this more it will remain freeform, but a recommended use of preinstall is to have it prompt for username and password, and then call the appropriate CREATE DATABASE commands etc.

PERL SCRIPTS

A perl script for this tool is very simple. It merely needs to contain an anonymous sub that takes a DBIx::Class::Schema as it's only argument. A very basic perl script might look like:

#!perl

use strict;
use warnings;

sub {
  my $schema = shift;

  $schema->resultset('Users')->create({
    name => 'root',
    password => 'root',
  })
}

ATTRIBUTES

schema

The DBIx::Class::Schema (required) that is used to talk to the database and generate the DDL.

storage

The DBIx::Class::Storage that is actually used to talk to the database and generate the DDL. This is automatically created with "_build_storage".

sql_translator_args

The arguments that get passed to SQL::Translator when it's used.

upgrade_directory

The directory (default 'sql') that upgrades are stored in

databases

The types of databases (default [qw( MySQL SQLite PostgreSQL )]) to generate files for

txn_wrap

Set to true (which is the default) to wrap all upgrades and deploys in a single transaction.

schema_version

The version the schema on your harddrive is at. Defaults to $self->schema->schema_version.

METHODS

__ddl_consume_with_prefix

$dm->__ddl_consume_with_prefix( 'SQLite', [qw( 1.00 1.01 )], 'up' )

This is the meat of the multi-file upgrade/deploy stuff. It returns a list of files in the order that they should be run for a generic "type" of upgrade. You should not be calling this in user code.

_ddl_schema_consume_filenames

$dm->__ddl_schema_consume_filenames( 'SQLite', [qw( 1.00 )] )

Just a curried "__ddl_consume_with_prefix". Get's a list of files for an initial deploy.

_ddl_schema_produce_filename

$dm->__ddl_schema_produce_filename( 'SQLite', [qw( 1.00 )] )

Returns a single file in which an initial schema will be stored.

_ddl_schema_up_consume_filenames

$dm->_ddl_schema_up_consume_filenames( 'SQLite', [qw( 1.00 )] )

Just a curried "__ddl_consume_with_prefix". Get's a list of files for an upgrade.

_ddl_schema_down_consume_filenames

$dm->_ddl_schema_down_consume_filenames( 'SQLite', [qw( 1.00 )] )

Just a curried "__ddl_consume_with_prefix". Get's a list of files for a downgrade.

_ddl_schema_up_produce_filenames

$dm->_ddl_schema_up_produce_filename( 'SQLite', [qw( 1.00 1.01 )] )

Returns a single file in which the sql to upgrade from one schema to another will be stored.

_ddl_schema_down_produce_filename

$dm->_ddl_schema_down_produce_filename( 'SQLite', [qw( 1.00 1.01 )] )

Returns a single file in which the sql to downgrade from one schema to another will be stored.

_resultsource_install_filename

my $filename_fn = $dm->_resultsource_install_filename('User');
$dm->$filename_fn('SQLite', '1.00')

Returns a function which in turn returns a single filename used to install a single resultsource. Weird interface is convenient for me. Deal with it.

_run_sql_and_perl

$dm->_run_sql_and_perl([qw( list of filenames )])

Simply put, this runs the list of files passed to it. If the file ends in .sql it runs it as sql and if it ends in .pl it runs it as a perl file.

Depending on "txn_wrap" all of the files run will be wrapped in a single transaction.

_prepare_install

$dm->_prepare_install({ add_drop_table => 0 }, sub { 'file_to_create' })

Generates the sql file for installing the database. First arg is simply SQL::Translator args and the second is a coderef that returns the filename to store the sql in.

_prepare_changegrade

$dm->_prepare_changegrade('1.00', '1.01', [qw( 1.00 1.01)], 'up')

Generates the sql file for migrating from one schema version to another. First arg is the version to start from, second is the version to go to, third is the version set, and last is the direction of the changegrade, be it 'up' or 'down'.

_read_sql_file

$dm->_read_sql_file('foo.sql')

Reads a sql file and returns lines in an ArrayRef. Strips out comments, transactions, and blank lines.

AUTHOR

Arthur Axel "fREW" Schmidt <frioux+cpan@gmail.com>

COPYRIGHT AND LICENSE

This software is copyright (c) 2010 by Arthur Axel "fREW" Schmidt.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.