Module: ActiveSupport::PerThreadRegistry
Relationships & Source Files | |
Extension / Inclusion / Inheritance Descendants | |
Extended In:
ActiveRecord::ExplainRegistry,
ActiveRecord::Relation::RecordFetchWarning::QueryRegistry,
ActiveRecord::RuntimeRegistry,
ActiveRecord::Scoping::ScopeRegistry,
ActiveRecord::SuppressorRegistry,
ActiveSupport::Cache::Strategy::LocalCache::LocalCacheRegistry,
ActiveSupport::Notifications::InstrumentationRegistry,
ActiveSupport::SubscriberQueueRegistry
| |
Defined in: | activesupport/lib/active_support/per_thread_registry.rb |
Overview
NOTE: This approach has been deprecated for end-user code in favor of thread_mattr_accessor and friends. Please use that approach instead.
This module is used to encapsulate access to thread local variables.
Instead of polluting the thread locals namespace:
Thread.current[:connection_handler]
you define a class that extends this module:
module ActiveRecord
class RuntimeRegistry
extend ActiveSupport::PerThreadRegistry
attr_accessor :connection_handler
end
end
and invoke the declared instance accessors as class methods. So
ActiveRecord::RuntimeRegistry.connection_handler = connection_handler
sets a connection handler local to the current thread, and
ActiveRecord::RuntimeRegistry.connection_handler
returns a connection handler local to the current thread.
This feature is accomplished by instantiating the class and storing the instance as a thread local keyed by the class name. In the example above a key “ActiveRecord::RuntimeRegistry” is stored in Thread.current
. The class methods proxy to said thread local instance.
If the class has an initializer, it must accept no arguments.
Class Method Summary
Instance Method Summary
Dynamic Method Handling
This class handles dynamic methods through the method_missing method
#method_missing(name, *args, &block) (private)
[ GitHub ]# File 'activesupport/lib/active_support/per_thread_registry.rb', line 51
def method_missing(name, *args, &block) # Caches the method definition as a singleton method of the receiver. # # By letting #delegate handle it, we avoid an enclosure that'll capture args. singleton_class.delegate name, to: :instance send(name, *args, &block) end
Class Method Details
.extended(object)
[ GitHub ]# File 'activesupport/lib/active_support/per_thread_registry.rb', line 42
def self.extended(object) object.instance_variable_set :@per_thread_registry_key, object.name.freeze end
Instance Method Details
#instance
[ GitHub ]# File 'activesupport/lib/active_support/per_thread_registry.rb', line 46
def instance Thread.current[@per_thread_registry_key] ||= new end