Thread Inheritable Attributes

Passes thread variables to child spawned threads. Main use case is enabling logging in child thread to keep context of a request. State only flows in one direction into the child threads and not back.

Installation

Add this line to your application's Gemfile:

gem "thread-inheritable_attributes"

request_store is a dependency for when working within the context of a multi-threaded web server. In that context Threads can be reused for different request causing state from a previous request to stick around to the next request. Unless your are manually reinitializing or clearing the state in your own Rack Middleware (at the start of a request) it is recommended that you also include the request_store gem.

If using Rails no config is required, except including the gem. When using other Rack based frameworks see docs for including middleware.

gem "request_store"

And then execute:

$ bundle

Or install it yourself as:

$ gem install thread-inheritable_attributes

Usage

require "thread/inheritable_attributes"

Thread.current.set_inheritable_attribute(:request_id, SecureRandom.uuid)

thread = Thread.new {
          Thread.current.get_inheritable_attribute(:request_id)
        }
thread.join
thread.value
  #=> "80f58e0f-0564-487d-8f92-4cff8237af24"

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/zeisler/thread_variable_cascade. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.

License

The gem is available as open source under the terms of the MIT License.