How to use CrawlSpider from scrapy to click a link with javascript onclick?

Question

I want scrapy to crawl pages where going to the next one link looks like this: Next

Will scrapy be able to interpret javascript code of that?

With livehttpheaders extension I found out that clicking Next generates a POST with a really huge piece of "garbage" starting like this: encoded_session_hidden_map=H4sIAAAAAAAAALWZXWwj1RXHJ9n

I am trying to build my spider on the CrawlSpider class, but I can't really figure out how to code it, with BaseSpider I used the parse() method to process the first URL, which happens to be a login form, where I did a POST with:

def logon(self, response):
    login_form_data={ 'email': '[email protected]', 'password': 'mypass22', 'action': 'sign-in' }
    return [FormRequest.from_response(response, formnumber=0, formdata=login_form_data, callback=self.submit_next)]

And then I defined submit_next() to tell what to do next. I can't figure out how do I tell CrawlSpider which method to use on the first URL?

All requests in my crawling, except the first one, are POST requests. They are alternating two types of requests: pasting some data, and clicking "Next" to go to the next page.