1
0
Fork 0
mirror of https://github.com/rails/rails.git synced 2022-11-09 12:12:34 -05:00
rails--rails/activerecord/lib/active_record.rb
Guo Xiang Tan 45add34478
Move advisory locks to own connection handler.
Removes the use of `ActiveRecord::AdvisoryLockBase` since it inherits
from `ActiveRecord::Base` and hence share module attributes that are defined in `ActiveRecord::Base`.
This is problematic because establishing connections through
`ActiveRecord::AdvisoryLockBase` can end up changing state of the default
connection handler of `ActiveRecord::Base` leading to unexpected
behaviors in a Rails application.

In the case of https://github.com/rails/rails/issues/39157,

Running migrations with `rails db:migrate:primary_shard_one` was not working as
the application itself defined the following

```
class ApplicationRecord < ActiveRecord::Base
  self.abstract_class = true

  connects_to shards: {
    default: { writing: :primary },
    shard_one: { writing: :primary_shard_one }
  }
end
```

In the database migrate rake task, the default connection was
established with the database config of `primary_shard_one`. However,
the default connection was altered to that of `primary` because
`ActiveRecord::AdvisoryLockBase.establish_connection` ended up loading
`ApplicationRecord` which calls `connects_to shards:`. Since all we
really need here is just a normal database connection, we can avoid
accidentally altering the default connection handler state during the migration
by creating a custom connection handler used for retrieving a connection.
2020-08-04 10:17:41 +08:00

188 lines
5.1 KiB
Ruby

# frozen_string_literal: true
#--
# Copyright (c) 2004-2020 David Heinemeier Hansson
#
# Permission is hereby granted, free of charge, to any person obtaining
# a copy of this software and associated documentation files (the
# "Software"), to deal in the Software without restriction, including
# without limitation the rights to use, copy, modify, merge, publish,
# distribute, sublicense, and/or sell copies of the Software, and to
# permit persons to whom the Software is furnished to do so, subject to
# the following conditions:
#
# The above copyright notice and this permission notice shall be
# included in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
#++
require "active_support"
require "active_support/rails"
require "active_model"
require "arel"
require "yaml"
require "active_record/version"
require "active_model/attribute_set"
require "active_record/errors"
module ActiveRecord
extend ActiveSupport::Autoload
autoload :Base
autoload :Callbacks
autoload :Core
autoload :ConnectionHandling
autoload :CounterCache
autoload :DynamicMatchers
autoload :DelegatedType
autoload :Enum
autoload :InternalMetadata
autoload :Explain
autoload :Inheritance
autoload :Integration
autoload :Migration
autoload :Migrator, "active_record/migration"
autoload :ModelSchema
autoload :NestedAttributes
autoload :NoTouching
autoload :TouchLater
autoload :Persistence
autoload :QueryCache
autoload :Querying
autoload :ReadonlyAttributes
autoload :RecordInvalid, "active_record/validations"
autoload :Reflection
autoload :RuntimeRegistry
autoload :Sanitization
autoload :Schema
autoload :SchemaDumper
autoload :SchemaMigration
autoload :Scoping
autoload :Serialization
autoload :StatementCache
autoload :Store
autoload :SignedId
autoload :Suppressor
autoload :Timestamp
autoload :Transactions
autoload :Translation
autoload :Validations
autoload :SecureToken
eager_autoload do
autoload :ConnectionAdapters
autoload :Aggregations
autoload :Associations
autoload :AttributeAssignment
autoload :AttributeMethods
autoload :AutosaveAssociation
autoload :LegacyYamlAdapter
autoload :Relation
autoload :AssociationRelation
autoload :NullRelation
autoload_under "relation" do
autoload :QueryMethods
autoload :FinderMethods
autoload :Calculations
autoload :PredicateBuilder
autoload :SpawnMethods
autoload :Batches
autoload :Delegation
end
autoload :Result
autoload :TableMetadata
autoload :Type
end
module Coders
autoload :YAMLColumn, "active_record/coders/yaml_column"
autoload :JSON, "active_record/coders/json"
end
module AttributeMethods
extend ActiveSupport::Autoload
eager_autoload do
autoload :BeforeTypeCast
autoload :Dirty
autoload :PrimaryKey
autoload :Query
autoload :Read
autoload :TimeZoneConversion
autoload :Write
autoload :Serialization
end
end
module Locking
extend ActiveSupport::Autoload
eager_autoload do
autoload :Optimistic
autoload :Pessimistic
end
end
module Scoping
extend ActiveSupport::Autoload
eager_autoload do
autoload :Named
autoload :Default
end
end
module Middleware
extend ActiveSupport::Autoload
autoload :DatabaseSelector, "active_record/middleware/database_selector"
end
module Tasks
extend ActiveSupport::Autoload
autoload :DatabaseTasks
autoload :SQLiteDatabaseTasks, "active_record/tasks/sqlite_database_tasks"
autoload :MySQLDatabaseTasks, "active_record/tasks/mysql_database_tasks"
autoload :PostgreSQLDatabaseTasks,
"active_record/tasks/postgresql_database_tasks"
end
autoload :TestDatabases, "active_record/test_databases"
autoload :TestFixtures, "active_record/fixtures"
def self.eager_load!
super
ActiveRecord::Locking.eager_load!
ActiveRecord::Scoping.eager_load!
ActiveRecord::Associations.eager_load!
ActiveRecord::AttributeMethods.eager_load!
ActiveRecord::ConnectionAdapters.eager_load!
end
end
ActiveSupport.on_load(:active_record) do
Arel::Table.engine = self
end
ActiveSupport.on_load(:i18n) do
I18n.load_path << File.expand_path("active_record/locale/en.yml", __dir__)
end
YAML.load_tags["!ruby/object:ActiveRecord::AttributeSet"] = "ActiveModel::AttributeSet"
YAML.load_tags["!ruby/object:ActiveRecord::Attribute::FromDatabase"] = "ActiveModel::Attribute::FromDatabase"
YAML.load_tags["!ruby/object:ActiveRecord::LazyAttributeHash"] = "ActiveModel::LazyAttributeHash"
YAML.load_tags["!ruby/object:ActiveRecord::ConnectionAdapters::AbstractMysqlAdapter::MysqlString"] = "ActiveRecord::Type::String"