Barenboim

Barenboim is prepared to tackle with data streaming dependencies in concurrent flows.

If your application works with a data streaming and your incoming events could have dependencies between them, the app can have problems when:

• The Application which is sending the data is not sending the data in the right order.
• Your Application is treating the data concurrently therefore the order is not ensured.

Installation

Add barenboim to your list of dependencies in mix.exs:

  def deps do
    [{:barenboim, "~> 0.3.1"}]
  end

Configuration

Barenboim uses poolboy and you can configure it depending on your needs:

  config :barenboim,
    pool_domain: :global,     # default :local
    pool_size: 20,            # default 10
    max_overflow: 3           # default 5

You can also configure a delay for a reminder notification. A reminder notification is sent in order to avoid corner cases (notification between the data access and the registration of a dependency). This time (milliseconds) should be defined depending on your data access function time (see next section).

  config :barenboim,
    reminder_time: 50     # default 100

How to use it

Define the function that will retrieve the dependency data where dependency_ref is the reference of your data and call Barenboim.get_data. You can also specify a time out in milliseconds.

  fun = fn(dependency_ref) -> MyDataModule.get(dependency_ref) end
  {:ok, data} = Barenboim.get_data(dependency_ref, fun)

Meanwhile, the flow that is processing a new event has to notify when the data is available for others.

  Barenboim.notify({:reference, dependency_ref})

Or you can even attach the data:

  Barenboim.notify({:data, dependency_ref, dependency_data})

Test

Run the tests.

  mix test 

In honor of

Daniel Barenboim