Piper

A minimal tool for building and evaluating Dataflow graphs of dependent steps.

Uses a simple DAG (Directed Acyclic Graph) model for building a static representation of dependencies between Steps. This is just a datastructure so it doesn't impose any runtime execution constraints.

Piper was implemented for demonstration purposes, and as such is not published to Hex.

Feel free to fork, or vendor into your own project should you find this pattern useful.

Usage

Any implementation of the Piper.Runner behaviour may execute the set of Runnables/Tasks/Jobs returned by the Piper.next_runnables/2 function using Piper.run/1 in a runtime context.

Any runnable returned by next_runnables/2 is guaranteed to be parallelizeable in context to other runnables so a Piper.Runner can safely dispatch these tasks to separate processes.

Installation

If available in Hex, the package can be installed by adding piper to your list of dependencies in mix.exs:

def deps do
  [
    {:piper, "~> 0.1.0"}
  ]
end

Documentation can be generated with ExDoc and published on HexDocs. Once published, the docs can be found at https://hexdocs.pm/piper.