Testing ajax from therubyracer (or execjs)?

Question

I want to test javascript code from a ruby context. Specifically, I want to setup my database with ruby, query it with my javascript model, and confirm my javascript state from ruby. I want to do this without mocking.

I've tried simply loading my client libraries into a v8 context, but that causes therubyracer to choke in all sorts of ways (window not defined, userAgent not defined, etc).

Further I'm using headless browsers to test my javascript code, but they don't provide me the ruby context I need to leverage for these cases.

I think I need to load a browser (or a dom simulator) into a v8 context, but i don't what libraries are out there to do this. Maybe you have another idea?

How can I do this?

score 2 · Accepted Answer · answered Jan 31 '12 at 18:32

2

I've used capybara-webkit for this kind of task. You don't actually need to use the RSpec helpers, you can also simply create an in-memory browser instance which you can direct to your HTML/Javascript. The advantage is that it provides a evaluate_script method that can be used to interact with the browser's Javascript context (to push/receive data).

Whether or not this is applicable in your case is what kind of "ruby context" you need to be able to access from the Javascript side.

There are also some other projects you might be interested in:

http://www.envjs.com/: browser emulation in JS
http://zombie.labnotes.org/: browser emulation in Node.js
https://github.com/LearnBoost/tobi: A similar approach to zombie

answered Jan 31 '12 at 18:32

Niklas B.

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hell yes! I didn't know about `evaluate_script`. I'll look into this. – Dane O'Connor Jan 31 '12 at 18:34
@thedeeno: The C++ side is very clean as well, I hacked in some of its features and it's really easy to extend, if you want more functionality. – Niklas B. Jan 31 '12 at 18:38
I've seen zombie, but I'm unsure how to leverage it from an rspec test. Do you have thoughts on this? – Dane O'Connor Jan 31 '12 at 18:58
@theedeeno: No, it's Node.js, nothing to do with Ruby, actually. – Niklas B. Jan 31 '12 at 18:58
Yeah, that makes sense. Was just making sure I wasn't misunderstanding something. – Dane O'Connor Jan 31 '12 at 18:59
can you show me how you access this evaluate_scrip method from rspec directly? I'm looking through the capybara source and it's not immediately apparent. You may know off hand since you've done this. – Dane O'Connor Jan 31 '12 at 19:18
nvm found it, under the session object. Looks like I can use `page.evaluate_script` from an rpsec method. – Dane O'Connor Jan 31 '12 at 19:22
@thedeeno: Glad you found it :) I actually never used capybara with RSpec, so I couldn't have been of much help after all. – Niklas B. Jan 31 '12 at 21:10

Testing ajax from therubyracer (or execjs)?

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