Restarting a process?

Questions / Help
,
10

I think I found one way of working with this based on this post.

First was to make the Broadway :name option overrideable by using Keyword.get/3 with a default value:

defmodule My.Pipeline do
    use Broadway

    def start_link(opts) do
        Broadway.start_link(__MODULE__,
        name: Keyword.get(opts, :name, __MODULE__),
        # ... etc ...
     )
   end
   # ... 
end

Then I can pass a unique :name option to my pipeline when I call start_supervised in my test:

test "start_link with custom options"
    {:ok, pid} = start_supervised({My.Pipeline,
                   [
                     queue_url: "fake-url",
                     producer: Broadway.DummyProducer,
                     # ... etc ...
                     name: :example
                   ]}
end

and it works equally well when I call start_link/1 directly:

{:ok, pid} = My.Pipeline.start_link(
                producer: Broadway.DummyProducer,
                queue_url: "fake-url",
              name: :something
              )

This works and I will probably use this method… the only downside I can see is that the regular built-in process in the application’s supervisor always starts… but we kinda just ignore it. That’s not a problem for my use case, however.

I think the docs for https://hexdocs.pm/ex_unit/master/ExUnit.Callbacks.html?#start_supervised/2 need some updating because they don’t really explain how to work with this common use case… I’m not sure what I did is even the proper way to work with that function… it just feels like a work-around more than anything else. Thoughts?

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