Front End Testing using Elixir

Have you gotten anywhere with this? I’ve found myself in exactly your situation and would love to know if you figured out a great way to do it!

Gotcha! This is what I was looking for. I’ll update this post when I have built a generic testing framework.

oh you will very much want to do this at the head of your mix task or else you’ll be wondering why nothing works:

    Application.ensure_all_started(:hound)
    Chromedriver.ensure_running()

# linux, very hacky, MacOS - ymmv
  @spec ensure_running(non_neg_integer) :: :ok
  def ensure_running(sleep_time \\ 500) do
    {ps, _} = System.cmd("ps", ["aux"])
    unless ps =~ "chromedriver" do
      chromedriver_executable = System.find_executable("chromedriver")

      {:ok, _pid} = Task.start(fn ->
        System.cmd(chromedriver_executable, [], stderr_to_stdout: true)
      end)

      Process.sleep(sleep_time)
    end
    :ok
  end

sadly I don’t have an open source version of the tester. I did kind of write a testing framework, but it’s not really ready to be open sourced anytime soon. It’s also somewhat tightly integrated into a set of releases, that’s probably more than you would need.

In your case I would recommand making a custom mix task.

That’s awesome! Any chance @ityonemo you can provide me a resource you used to build the tester, or do you have an open source version of the tester?

I’m trying to understand how to run hound or wallaby outside of testing

As a protip, if you do this, BEAM supervised restarts are key and I found that I needed to System.cmd(“killall”, [“chromedriver”]) on each restart, because I found that chromedriver could become helplessly lost in the face of our high-latency python frontend that doesn’t handle conflicting state very well, but that’s another story altogether.

Yes, 100%. At work I replaced a python backend with elixir (I’m coming for the python frontend next) and tested that it worked by running a user story continuously using hound for one week in our staging/lab environment (against the python frontend). Discovered several errors, and since deploying to prod there have been zero backend errors.

#question
I’m bring this post back to life to ask the following question. Is it possible to use Wallaby or Hound to test external sites, outside of ExUnit?

##Context:
I want to build a Front End QA tooling that has a set of endpoints for me to utilize from another website. Essentially I want to utilize the QA tool from website A to test website A. I understand this seem unnecessary, but I feel that this would be a good way for me to introduce Elixir to your company without impacting business logic.

We tried both out and ended up going with Wallaby. The experimental chrome driver has been working out great for us!

Thanks @tme_317 and @ityonemo for your insight. I’m going to take a look at both wallaby and hound. Ideally I would like go with the library that sees to build out.