HTTPoison issue on any URL

[marnen]

I'm running Wallaby 0.19.2 on a Debian Jessie Docker container (hosted on Mac OS X) with Elixir 1.6. Whenever I do session |> visit(any URL whatsoever), I get the following error:

** (RuntimeError) Wallaby had an internal issue with HTTPoison
    (wallaby) lib/wallaby/httpclient.ex:32: Wallaby.HTTPClient.make_request/4
    (wallaby) lib/wallaby/phantom/driver.ex:151: anonymous fn/2 in Wallaby.Phantom.Driver.visit/2
    (wallaby) lib/wallaby/driver/log_checker.ex:6: Wallaby.Driver.LogChecker.check_logs!/2
    (wallaby) lib/wallaby/browser.ex:703: Wallaby.Browser.visit/2

HTTPoison seems to be retrieving the pages just fine, but I believe the problem is that Wallaby is attempting to decode the resulting HTML as if it were JSON (see https://github.com/keathley/wallaby/blob/v0.19.2/lib/wallaby/httpclient.ex#L54, where the first thing it does is run Poison.decode(body), which fails since the result isn't JSON). Help?

[marnen]

On reflection, I'm not sure I'm right about the JSON issue, since I suppose Wallaby would have to be making requests to the PhantomJS endpoint, not directly to the desired HTML page. But I definitely can't get Wallaby to visit any page successfully, even though those pages can successfully be seen by a client such as HTTPoison.

[marnen]

Oh, and I'm using PhantomJS 2.1.1 and setting QT_QPA_PLATFORM=offscreen as recommended here.

[marnen]

I think I was wrong about the root cause here:

> {status, %HTTPoison.Response{}} = HTTPoison.get session.url
> status
:ok
>  HTTPoison.post session.url, Poison.encode!(%{url: Endpoint.url})
{:error, %HTTPoison.Error{id: nil, reason: :timeout}}

So for some reason the session URL (that's the PhantomJS endpoint, right?) is timing out on POST but not on GET.

[marnen]

I think there was a twofold problem.

• I was using the PhantomJS installation from jessie-backports, which doesn't appear to work with Wallaby. I switched to the NPM phantom-prebuilt package.
• I was also setting QT_QPA_PLATFORM=offscreen as required for PhantomJS 2.1.3. Unfortunately, 2.1.1 (which both backports and the Node package use) doesn't work if I do that.

So...problem solved by switching to phantom-prebuilt and not setting QT_QPA_PLATFORM. Is it worth warning against the jessie-backports version of PhantomJS in the docs?

[PragTob]

@marnen thanks for the investigation. It might be worth specifying what version of phantomjs we expect, yes :)

[marnen]

Not sure why this was closed, given that the docs were never updated...

[keathley]

If you would like to submit a PR that updates the docs then that would be great. Otherwise we're planning on moving to chrome as the default driver since phantom is deprecated so this problem will be lessened.

[marnen]

Oh, OK. If this is moot then I won’t bother, but I’ll try to add a sentence or two.