Hassan Schroeder wrote: > On Fri, Jan 2, 2009 at 4:08 PM, Jonathan Rochkind > <[email protected]> wrote: >> >> ... url_for [helper method] seperates query parameters with >> & url_for the controller method does >> not.
> Why "unpredictable"? HTML requires ampersands to be escaped, > as part of URLs or otherwise. > > A URL in plain text format, though, should not have ampersands > escaped. I knew that a URL in xHTML required ampersands to be escaped like that, even in an <a href>. I did not know that a URL in standard (non-x)HTML required that. Really? Okay. But it's confusing in part because an ERB template isn't _only_ used for HTML. It can theoretically be used for creating any format, including plain text, right? And someone using an ERB template to create (eg) plain text is going to get tripped up there. In my case, I wasn't creating plain text, I was creating XML with an ERB template. Which should be a perfectly fine thing to do, right? Sure, you can use Builder if you want for XML, but you should be able to use an ERB template too, right? But this definitely isn't the first time I've been confused by the proper amount of escaping of an ampersand in a complicated data flow. I'm still not exactly sure if I fixed my bug in the right part of my somewhat complicated chain of data flow. I'd appreciate if you have any insight, Hassan. Here's what was going on: An ERB template was generating XML. It took the result of a url_for call, and put it through an XML-escaping routine, figuring that anything that was being put in XML should be put through an XML escaping routine. (Is this where I went wrong? Not sure.) So we wound up with XML who's source looked like <some_url>/controller/action?foo=foo&amp;bar=bar Is this correct or not? Not sure. Later in the program execution, this XML gets converted to JSON, and the JSON winds up looking like: some_url: '/controller/action?foo=foo&bar=bar'; This part was right, that is a proper JSON translation of the XML passed in, right, it un-escaped the XML properly, put it in JSON. Then, this JSON gets delivered via JSONP to some javascript (external javascript not generated by rails). The javascript gets that value in a variable, containing '/controller/action?foo=foo&bar=bar'. So far so good, it got the right value from the JSON delivered to it. Now, if that had been in HTML source for an <a href>, I guess the browser would have 'un-escaped' that before making the HTTP request. But it wasn't in HTML source, it was in a javascript variable. And when I passed this variable to my javascript routine to load the URL (AJAX-style), it ended up submitting a GET to the HTTP server that looked like this: GET /controller/action?foo=foo&bar=bar That wound up being caught by a mongrel-fronted Rails app, which did NOT turn that into query parameters foo => foo, bar => bar properly, it did weird things with that GET request. So. At what point did that code go wrong? At the moment, I've fixed my XML-generating ERB to _not_ escape urls generated by url_for. But I'm not sure that's right, it doesn't feel right. Or is it my javascript code that took a js variable containing '/controller/action?foo=foo&bar=bar' and made a GET of that literal string, instead of un-escaping it first, that went wrong? Or something else? I'm very confused. And, since ERB can be used to generate all kinds of formats, it still seems to me that the documentation should mention this feature, which would have gotten me to my present state of confusion several hours earlier---ah, but when I go look at the most recent rdoc ActionView url_for, I see that it was there all along, my fault for missing it: "When called from a view, url_for returns an HTML escaped url. If you need an unescaped url, pass :escape => false in the options." So good on the rdoc after all. Still somewhat confused as to whether I should be "double escaping" it in the XML or not. Jonathan -- Posted via http://www.ruby-forum.com/. --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---
