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Active Record DatabaseTasks

ActiveRecord::Tasks::DatabaseTasks is a utility class, which encapsulates logic behind common tasks used to manage database and migrations.

The tasks defined here are used with Rails commands 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.

  • root: a path to the root of the application.

Example usage of DatabaseTasks outside Rails could look as such:

include ActiveRecord::Tasks
DatabaseTasks.database_configuration = YAML.load_file('my_database_config.yml')
DatabaseTasks.db_dir = 'db'
# other settings...

DatabaseTasks.create_current('production')
Methods
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Constants

LOCAL_HOSTS = ["127.0.0.1", "localhost"]
 

Attributes

[RW] database_configuration
[W] db_dir
[W] env
[W] fixtures_path
[W] migrations_paths
[W] root
[W] seed_loader

Class Public methods

structure_dump_flags

Extra flags passed to database CLI tool (mysqldump/pg_dump) when calling db:schema:dump It can be used as a string/array (the typical case) or a hash (when you use multiple adapters) Example:

ActiveRecord::Tasks::DatabaseTasks.structure_dump_flags = {
  mysql2: ['--no-defaults', '--skip-add-drop-table'],
  postgres: '--no-tablespaces'
}

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 50
mattr_accessor :structure_dump_flags, instance_accessor: false

structure_load_flags

Extra flags passed to database CLI tool when calling db:schema:load It can be used as a string/array (the typical case) or a hash (when you use multiple adapters)

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 56
mattr_accessor :structure_load_flags, instance_accessor: false

Instance Public methods

cache_dump_filename(db_config_name, schema_cache_path: nil)

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 440
def cache_dump_filename(db_config_name, schema_cache_path: nil)
  filename = if ActiveRecord::Base.configurations.primary?(db_config_name)
    "schema_cache.yml"
  else
    "#{db_config_name}_schema_cache.yml"
  end

  schema_cache_path || ENV["SCHEMA_CACHE"] || File.join(ActiveRecord::Tasks::DatabaseTasks.db_dir, filename)
end

charset(configuration, *arguments)

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 305
def charset(configuration, *arguments)
  db_config = resolve_configuration(configuration)
  database_adapter_for(db_config, *arguments).charset
end

charset_current(env_name = env, db_name = name)

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 300
def charset_current(env_name = env, db_name = name)
  db_config = configs_for(env_name: env_name, name: db_name)
  charset(db_config)
end

check_protected_environments!(environment = env)

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 65
def check_protected_environments!(environment = env)
  return if ENV["DISABLE_DATABASE_ENVIRONMENT_CHECK"]

  configs_for(env_name: environment).each do |db_config|
    check_current_protected_environment!(db_config)
  end
end

check_schema_file(filename)

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 458
def check_schema_file(filename)
  unless File.exist?(filename)
    message = +%{#{filename} doesn't exist yet. Run `bin/rails 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.root)
    Kernel.abort message
  end
end

check_target_version()

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 290
def check_target_version
  if target_version && !Migration.valid_version_format?(ENV["VERSION"])
    raise "Invalid format of target version: `VERSION=#{ENV['VERSION']}`"
  end
end

clear_schema_cache(filename)

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 484
def clear_schema_cache(filename)
  FileUtils.rm_f filename, verbose: false
end

collation(configuration, *arguments)

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 315
def collation(configuration, *arguments)
  db_config = resolve_configuration(configuration)
  database_adapter_for(db_config, *arguments).collation
end

collation_current(env_name = env, db_name = name)

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 310
def collation_current(env_name = env, db_name = name)
  db_config = configs_for(env_name: env_name, name: db_name)
  collation(db_config)
end

create(configuration, *arguments)

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 115
def create(configuration, *arguments)
  db_config = resolve_configuration(configuration)
  database_adapter_for(db_config, *arguments).create
  $stdout.puts "Created database '#{db_config.database}'" if verbose?
rescue DatabaseAlreadyExists
  $stderr.puts "Database '#{db_config.database}' already exists" if verbose?
rescue Exception => error
  $stderr.puts error
  $stderr.puts "Couldn't create '#{db_config.database}' database. Please check your configuration."
  raise
end

create_all()

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 127
def create_all
  db_config = migration_connection.pool.db_config

  each_local_configuration { |db_config| create(db_config) }

  migration_class.establish_connection(db_config)
end

create_current(environment = env, name = nil)

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 170
def create_current(environment = env, name = nil)
  each_current_configuration(environment, name) { |db_config| create(db_config) }

  migration_class.establish_connection(environment.to_sym)
end

db_dir()

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 83
def db_dir
  @db_dir ||= Rails.application.config.paths["db"].first
end

drop(configuration, *arguments)

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 204
def drop(configuration, *arguments)
  db_config = resolve_configuration(configuration)
  database_adapter_for(db_config, *arguments).drop
  $stdout.puts "Dropped database '#{db_config.database}'" if verbose?
rescue ActiveRecord::NoDatabaseError
  $stderr.puts "Database '#{db_config.database}' does not exist"
rescue Exception => error
  $stderr.puts error
  $stderr.puts "Couldn't drop database '#{db_config.database}'"
  raise
end

drop_all()

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 216
def drop_all
  each_local_configuration { |db_config| drop(db_config) }
end

drop_current(environment = env)

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 220
def drop_current(environment = env)
  each_current_configuration(environment) { |db_config| drop(db_config) }
end

dump_schema_cache(conn, filename)

Dumps the schema cache in YAML format for the connection into the file

Examples

ActiveRecord::Tasks::DatabaseTasks.dump_schema_cache(ActiveRecord::Base.connection, "tmp/schema_dump.yaml")

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 480
def dump_schema_cache(conn, filename)
  conn.schema_cache.dump_to(filename)
end

env()

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 103
def env
  @env ||= Rails.env
end

fixtures_path()

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 91
def fixtures_path
  @fixtures_path ||= if ENV["FIXTURES_PATH"]
    File.join(root, ENV["FIXTURES_PATH"])
  else
    File.join(root, "test", "fixtures")
  end
end

load_schema_current(format = ActiveRecord.schema_format, file = nil, environment = env)

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 450
def load_schema_current(format = ActiveRecord.schema_format, file = nil, environment = env)
  each_current_configuration(environment) do |db_config|
    with_temporary_connection(db_config) do
      load_schema(db_config, format, file)
    end
  end
end

load_seed()

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 466
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

migrate(version = nil)

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 237
def migrate(version = nil)
  scope = ENV["SCOPE"]
  verbose_was, Migration.verbose = Migration.verbose, verbose?

  check_target_version

  migration_connection.migration_context.migrate(target_version) do |migration|
    if version.blank?
      scope.blank? || scope == migration.scope
    else
      migration.version == version
    end
  end.tap do |migrations_ran|
    Migration.write("No migrations ran. (using #{scope} scope)") if scope.present? && migrations_ran.empty?
  end

  migration_connection.schema_cache.clear!
ensure
  Migration.verbose = verbose_was
end

migrate_status()

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 275
def migrate_status
  unless migration_connection.schema_migration.table_exists?
    Kernel.abort "Schema migrations table does not exist yet."
  end

  # output
  puts "\ndatabase: #{migration_connection.pool.db_config.database}\n\n"
  puts "#{'Status'.center(8)}  #{'Migration ID'.ljust(14)}  Migration Name"
  puts "-" * 50
  migration_connection.migration_context.migrations_status.each do |status, version, name|
    puts "#{status.center(8)}  #{version.ljust(14)}  #{name}"
  end
  puts
end

migrations_paths()

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 87
def migrations_paths
  @migrations_paths ||= Rails.application.paths["db/migrate"].to_a
end

name()

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 107
def name
  @name ||= "primary"
end

prepare_all()

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 176
def prepare_all
  seed = false

  each_current_configuration(env) do |db_config|
    with_temporary_pool(db_config) do
      begin
        database_initialized = migration_connection.schema_migration.table_exists?
      rescue ActiveRecord::NoDatabaseError
        create(db_config)
        retry
      end

      unless database_initialized
        if File.exist?(schema_dump_path(db_config))
          load_schema(db_config, ActiveRecord.schema_format, nil)
        end

        seed = true
      end

      migrate
      dump_schema(db_config) if ActiveRecord.dump_schema_after_migration
    end
  end

  load_seed if seed
end

purge(configuration)

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 320
def purge(configuration)
  db_config = resolve_configuration(configuration)
  database_adapter_for(db_config).purge
end

purge_all()

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 325
def purge_all
  each_local_configuration { |db_config| purge(db_config) }
end

purge_current(environment = env)

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 329
def purge_current(environment = env)
  each_current_configuration(environment) { |db_config| purge(db_config) }

  migration_class.establish_connection(environment.to_sym)
end

register_task(pattern, task)

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# File activerecord/lib/active_record/tasks/database_tasks.rb, line 73
def register_task(pattern, task)
  @tasks ||= {}
  @tasks[pattern] = task
end

root()

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 99
def root
  @root ||= Rails.root
end

schema_dump_path(db_config, format = ActiveRecord.schema_format)

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 427
def schema_dump_path(db_config, format = ActiveRecord.schema_format)
  return ENV["SCHEMA"] if ENV["SCHEMA"]

  filename = db_config.schema_dump(format)
  return unless filename

  if File.dirname(filename) == ActiveRecord::Tasks::DatabaseTasks.db_dir
    filename
  else
    File.join(ActiveRecord::Tasks::DatabaseTasks.db_dir, filename)
  end
end

schema_up_to_date?(configuration, format = ActiveRecord.schema_format, file = nil)

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 370
def schema_up_to_date?(configuration, format = ActiveRecord.schema_format, file = nil)
  db_config = resolve_configuration(configuration)

  file ||= schema_dump_path(db_config)

  return true unless file && File.exist?(file)

  with_temporary_connection(db_config) do |connection|
    return false unless connection.internal_metadata.enabled?
    return false unless connection.internal_metadata.table_exists?

    connection.internal_metadata[:schema_sha1] == schema_sha1(file)
  end
end

seed_loader()

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 111
def seed_loader
  @seed_loader ||= Rails.application
end

structure_dump(configuration, *arguments)

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 335
def structure_dump(configuration, *arguments)
  db_config = resolve_configuration(configuration)
  filename = arguments.delete_at(0)
  flags = structure_dump_flags_for(db_config.adapter)
  database_adapter_for(db_config, *arguments).structure_dump(filename, flags)
end

structure_load(configuration, *arguments)

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 342
def structure_load(configuration, *arguments)
  db_config = resolve_configuration(configuration)
  filename = arguments.delete_at(0)
  flags = structure_load_flags_for(db_config.adapter)
  database_adapter_for(db_config, *arguments).structure_load(filename, flags)
end

target_version()

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 296
def target_version
  ENV["VERSION"].to_i if ENV["VERSION"] && !ENV["VERSION"].empty?
end

truncate_all(environment = env)

Source: show 

# File activerecord/lib/active_record/tasks/database_tasks.rb, line 231
def truncate_all(environment = env)
  configs_for(env_name: environment).each do |db_config|
    truncate_tables(db_config)
  end
end