GenStage is a specification for exchanging events between producers and consumers. It also provides a mechanism to specify the computational flow between stages.
This project currently provides the following functionality:
-
Experimental.GenStage(docs) - a behaviour for implementing producer and consumer stages -
Experimental.Flow(docs) -Flowallows developers to express computations on collections, similar to theEnumandStreammodules, although computations will be executed in parallel using multipleGenStages -
Experimental.DynamicSupervisor(docs) - a supervisor designed for starting children dynamically. Besides being a replacement for the:simple_one_for_onestrategy in the regularSupervisor, aDynamicSupervisorcan also be used as a stage consumer, making it straight-forward to spawn a new process for every event in a stage pipeline
The module names are marked as Experimental to avoid conflicts as they are meant to be included in future Elixir releases. In your code, you may add al
5F2A
ias Experimental.{DynamicSupervisor, Flow, GenStage} to the top of your files and use the relative names from then on.
You can find examples on how to use the modules above in the examples directory:
-
ProducerConsumer - a simple example of setting up a pipeline of
A -> B -> Cstages and having events flowing through -
DynamicSupervisor - an example of how to use one or more
DynamicSupervisoras a consumer to a producer that works as a counter -
GenEvent - an example of how to use
GenStageto implement aGenEventreplacement that leverages concurrency and provides more flexibility regarding buffer size and back-pressure
GenStage requires Elixir v1.3.
-
Add
:gen_stageto your list of dependencies in mix.exs:def deps do [{:gen_stage, "~> 0.4"}] end
-
Ensure
:gen_stageis started before your application:def application do [applications: [:gen_stage]] end
Here is a list of potential topics to be explored by this project (in no particular order or guarantee):
- Consider using DynamicSupervisor to implement Task.Supervisor (as a consumer)
Same as Elixir.