module ActiveRecord
module Tasks # :nodoc:
class DatabaseAlreadyExists < StandardError; end # :nodoc:
class DatabaseNotSupported < StandardError; end # :nodoc:
# <tt>ActiveRecord::Tasks::DatabaseTasks</tt> is a utility class, which encapsulates
# logic behind common tasks used to manage database and migrations.
#
# The tasks defined here are used in rake tasks provided by Active Record.
#
# In order to use DatabaseTasks, a few config values need to be set. All the needed
# config values are set by Rails already, so it's necessary to do it only if you
# want to change the defaults or when you want to use Active Record outside of Rails
# (in such case after configuring the database tasks, you can also use the rake tasks
# defined in Active Record).
#
#
# The possible config values are:
#
# * +env+: current environment (like Rails.env).
# * +database_configuration+: configuration of your databases (as in +config/database.yml+).
# * +db_dir+: your +db+ directory.
# * +fixtures_path+: a path to fixtures directory.
# * +migrations_paths+: a list of paths to directories with migrations.
# * +seed_loader+: an object which will load seeds, it needs to respond to the +load_seed+ method.
#
# Example usage of +DatabaseTasks+ outside Rails could look as such:
#
# include ActiveRecord::Tasks
# DatabaseTasks.database_configuration = YAML.load(File.read('my_database_config.yml'))
# DatabaseTasks.db_dir = 'db'
# # other settings...
#
# DatabaseTasks.create_current('production')
module DatabaseTasks
extend self
attr_writer :current_config
attr_accessor :database_configuration, :migrations_paths, :seed_loader, :db_dir,
:fixtures_path, :env
LOCAL_HOSTS = ['127.0.0.1', 'localhost']
def register_task(pattern, task)
@tasks ||= {}
@tasks[pattern] = task
end
register_task(/mysql/, ActiveRecord::Tasks::MySQLDatabaseTasks)
register_task(/postgresql/, ActiveRecord::Tasks::PostgreSQLDatabaseTasks)
register_task(/sqlite/, ActiveRecord::Tasks::SQLiteDatabaseTasks)
register_task(/firebird/, ActiveRecord::Tasks::FirebirdDatabaseTasks)
register_task(/sqlserver/, ActiveRecord::Tasks::SqlserverDatabaseTasks)
register_task(/(oci|oracle)/, ActiveRecord::Tasks::OracleDatabaseTasks)
def current_config(options = {})
options.reverse_merge! :env => env
if options.has_key?(:config)
@current_config = options[:config]
else
@current_config ||= if ENV['DATABASE_URL']
database_url_config
else
ActiveRecord::Base.configurations[options[:env]]
end
end
end
def create(*arguments)
configuration = arguments.first
class_for_adapter(configuration['adapter']).new(*arguments).create
rescue DatabaseAlreadyExists
$stderr.puts "#{configuration['database']} already exists"
rescue Exception => error
$stderr.puts error, *(error.backtrace)
$stderr.puts "Couldn't create database for #{configuration.inspect}"
end
def create_all
each_local_configuration { |configuration| create configuration }
end
def create_current(environment = env)
each_current_configuration(environment) { |configuration|
create configuration
}
ActiveRecord::Base.establish_connection environment
end
def create_database_url
create database_url_config
end
def drop(*arguments)
configuration = arguments.first
class_for_adapter(configuration['adapter']).new(*arguments).drop
rescue Exception => error
$stderr.puts error, *(error.backtrace)
$stderr.puts "Couldn't drop #{configuration['database']}"
end
def drop_all
each_local_configuration { |configuration| drop configuration }
end
def drop_current(environment = env)
each_current_configuration(environment) { |configuration|
drop configuration
}
end
def drop_database_url
drop database_url_config
end
def charset_current(environment = env)
charset ActiveRecord::Base.configurations[environment]
end
def charset(*arguments)
configuration = arguments.first
class_for_adapter(configuration['adapter']).new(*arguments).charset
end
def collation_current(environment = env)
collation ActiveRecord::Base.configurations[environment]
end
def collation(*arguments)
configuration = arguments.first
class_for_adapter(configuration['adapter']).new(*arguments).collation
end
def purge(configuration)
class_for_adapter(configuration['adapter']).new(configuration).purge
end
def structure_dump(*arguments)
configuration = arguments.first
filename = arguments.delete_at 1
class_for_adapter(configuration['adapter']).new(*arguments).structure_dump(filename)
end
def structure_load(*arguments)
configuration = arguments.first
filename = arguments.delete_at 1
class_for_adapter(configuration['adapter']).new(*arguments).structure_load(filename)
end
def check_schema_file(filename)
unless File.exists?(filename)
message = %{#{filename} doesn't exist yet. Run `rake db:migrate` to create it, then try again.}
message << %{ If you do not intend to use a database, you should instead alter #{Rails.root}/config/application.rb to limit the frameworks that will be loaded.} if defined?(::Rails)
Kernel.abort message
end
end
def load_seed
if seed_loader
seed_loader.load_seed
else
raise "You tried to load seed data, but no seed loader is specified. Please specify seed " +
"loader with ActiveRecord::Tasks::DatabaseTasks.seed_loader = your_seed_loader\n" +
"Seed loader should respond to load_seed method"
end
end
private
def database_url_config
@database_url_config ||=
ConnectionAdapters::ConnectionSpecification::Resolver.new(ENV["DATABASE_URL"], {}).spec.config.stringify_keys
end
def class_for_adapter(adapter)
key = @tasks.keys.detect { |pattern| adapter[pattern] }
unless key
raise DatabaseNotSupported, "Rake tasks not supported by '#{adapter}' adapter"
end
@tasks[key]
end
def each_current_configuration(environment)
environments = [environment]
environments << 'test' if environment == 'development'
configurations = ActiveRecord::Base.configurations.values_at(*environments)
configurations.compact.each do |configuration|
yield configuration unless configuration['database'].blank?
end
end
def each_local_configuration
ActiveRecord::Base.configurations.each_value do |configuration|
next unless configuration['database']
if local_database?(configuration)
yield configuration
else
$stderr.puts "This task only modifies local databases. #{configuration['database']} is on a remote host."
end
end
end
def local_database?(configuration)
configuration['host'].blank? || LOCAL_HOSTS.include?(configuration['host'])
end
end
end
end