Today, while I was working on the URL encoding for the recently released Facebook-style Links module, I realized a bug with Link Attachments feature on Facebook. Before I explain, let us reproduce it:
Try to attach the following link on Facebook: http://google.com/search?q=blenders%26pride. This URL actually queries Google for ‘blenders&pride’. Facebook converts/encodes the above URL to http://google.com/search?q=blenders&pride which is not the same as above and queries Google for just ‘blenders’.
So, why Facebook does this? Probably Facebook tries to encode the URL to remove the characters which are not allowed by RFC 3986 and replaces them with their percent encoding. But there are certain characters which should not be encoded, such as ‘/’, ‘?’, ‘#’, ‘@’ which are the reserved characters and used as delimiters in the URL. So, it decodes these characters and converts their encoding to the original character which gives rise to the problem. Let us see an example:
‘http://google.com/search?q= %2B‘ is first encoded to replace unwanted character with their percent encoding, turns into ‘http%3A%2F%2Fgoogle.com%2Fsearch%3Fq%3D%20%2B’. (Note: I assume that already encoded characters are not encoded again in order to reproduce the bug, i.e.%2B does not gets converted to %252B). Then, the reserved characters (/,:,?,=,@,+) must be decoded again, therefore it gets converted to ‘http://google.com/search?q=%20+‘ which as we see is not the same. It ideally should have been ‘http://google.com/search?q=%20%2B’.
I have already reported it in the bugs on Facebook. I will like to hear your views on URL encoding. Do you consider this as bug? Why does such URLs are not properly formatted at source making lives of developers difficult? Why does URLs with spaces and other disallowed characters exists?
Enjoy.
Related Resources:
[...] to the RSS feed for updates on this topic.I discussed a little about URL encoding in my recent post Facebook: Bug with URL encoding, although it seems like the bug still exists. In this post I will discuss “how to encode a [...]
Hello,
I’ve the same issue. I want to post a link on facebook to http://www.kinderenkoning.be/index.php?/Wishbonebike/View-all-products.html but facebook always converts it to http://www.kinderenkoning.be/index.php?%2FWishbonebike%2FView-all-products.html so the user clicks on it and gets a page not found
Question: how should I post my links now? All my URL’s contain “?/” on the site :-/
Peter
There is not much you can do about it until Facebook fixes the issue. I have already logged it with them, let’s hope it gets fixed soon. (http://bugs.developers.facebook.net/show_bug.cgi?id=9202)
Any luck with that issue?
I’m running the same problem now in my app;/
Nopes. Along with FB has closed the issue as “Not Reproducible”. I tried to convince them for a while but then had to back due to lack of time. You can log a bug with them and refer it here for reference.