如何在Minitest中测试rake任务？

Question

I have a rake task in my rails application that published jobs to facebook. And then changes some model values. So one way to test the rake task is to invoke the rake task and check values that have been changed.

test 'z' do
    # setup some data
    Rake::Task['job:publish_to_facebook'].invoke
    Rake::Task['job:publish_to_facebook'].reenable
    # assert table values that has been changed. 
end

But how I can test whether jobs are successfully published on facebook? Is there any better strategy except using capybara and selenium-webdriver ?

Even if i use stubbing and mocking then how can i verify that my jobs are published on facebook?

Answer 1

Most tests should not contact an external API, mainly because it will slow down tests and you might also run into rate limits.

Even if i use stubbing and mocking then how can i verify that my jobs are published on facebook?

The point of stubbing and mocking is precisely not to publish to Facebook. Instead, you would create a class called Facebook (for example) with a method like def post_message(message) . This is the app's front door to Facebook, all calls to Facebook go through this class. Then you can use a library like Mocha to overwrite def post_message during testing. You can use it to verify that the application is attempting to post a message, and verify the message itself is correct. It won't actually post the message.

As I mentioned, you do want to make some tests with real calls to Facebook (though not many). These could be in a test like you've shown above, which is an integration test, or it could also be a smaller unit test of the Facebook class I suggested above, which would be a better starting point. For this purpose, you'd want to establish a test account on Facebook. Then your test should clear all messages in the setup and use Facebook's API to verify that the messages were actually posted.