You're not likely to find the requirement explicitly spelled out in the OAuth specification, but Twitter, along with many other OAuth providers, use the timestamp as an additional check point that the request is timely. This is especially important in the token negotiation steps where elements of the request are transitory and shouldn't be held in memory or stored for longer than is necessary. Some providers are even stricter about timestamp variance than we are.
Taylor Singletary Developer Advocate, Twitter http://twitter.com/episod On Tue, May 25, 2010 at 7:36 PM, Eric Woodward <e...@nambu.com> wrote: > > Thanks. I did look through the archives before posting but did not > find anything. I will look harder next time. I still don't see where > in the OAuth specifications it says this comparison is necessary, but > I will continue to look around. > > --ejw > > Eric Woodward > Email: e...@nambu.com > > > On May 25, 5:49 pm, "Brian Smith" <br...@briansmith.org> wrote: >> This is known and expected behavior. There have been other threads about it >> in the last couple of weeks. If you get a 401 response, you should compare >> the Date header of Twitter's response to the current system time. If it is >> significantly off then you should warn the user so they can fix it and/or >> calculate the difference and add that offset to all your timestamps. More >> details are available in the mailing list archive. >> >> Regards, >> Brian >> >> >> >> >> >> > -----Original Message----- >> > From: twitter-development-talk@googlegroups.com [mailto:twitter- >> > development-t...@googlegroups.com] On Behalf Of Eric Woodward >> > Sent: Tuesday, May 25, 2010 7:40 PM >> > To: Twitter Development Talk >> > Subject: [twitter-dev] Twitter OAuth & Timestamps >> >> > I have confirmed a problem with xAuth/OAUth that I believe resides within >> > Twitter OAuth implementation that has been a thorn in our side for a >> while. I say >> > *believe* because I do not claim to know for sure, thus this post. >> >> > I assume no one at Twitter will be inclined to do me any favours, but >> please >> > answer for the sake of the users in general, and other developers in here >> that do >> > a better job of not publicly expressing their opinions of what Twitter has >> been >> > doing to its ecosystem. >> >> > If a user's desktop time is off by a significant margin, say 30m, we have >> > confirmed that a valid username/password via an xAuth request will fail. >> This has >> > been very painful to track down since those working on Nambu tend to have >> the >> > desktop time set correctly, and only a handful users complain >> legitimately, with >> > credibility. This tweet started us on to a solution: >> >http://twitter.com/imhassan/status/14639986090. >> > It is not affecting just Nambu. >> >> > I cant find anything in the OAuth specs to suggest this comparison to the >> actual >> > time should take place, so I assume Twitter is just going ahead and >> comparing >> > the submitted timestamp to the actual time, and rejecting the request (for >> > perhaps a good reason), or it is a bug. We are getting a 401 on a valid >> request >> > with an inaccurate timestamp. >> >> > This issue is hinted at here:http://weblog.bluedonkey.org/?p=959. >> >> > Anyway, we are putting a workaround in place, so if no one at Twitter >> responds, >> > no worries, Nambu will work going forward. Other developers, be aware that >> > this issue exists. This is very annoying to me because users with >> inaccurate time >> > settings have tried to verify their accounts in Nambu, failed, and then >> use the >> > official Twitter application for OSX (aka Tweetie), which works because it >> is still >> > on HTTP Basic authentication, and declared Nambu to be broken. >> >> > Twitter, please clarify which part of the process is indeed broken, and >> what you >> > expect to see regarding timestamps on your end. I assume that by the time >> > Twitter for OSX is updated to use xAuth you will have put a solution in >> place for >> > this, or will at some point soon afterward as users complain. It would be >> nice if >> > you outlined that solution for the rest of us when the time comes, so >> perhaps >> > we can improve on what we have come up with. >> >> > I apologize in advance if I missed something obvious in the docs >> somewhere. I >> > am not an expert on OAuth by any means, and have not studied this issue >> per se. >> > I have only been trying to resolve the issue for us to move on to >> something more >> > important. Our OAuth implementation works fine otherwise. Well, as well as >> the >> > rest of the Twitter API "works", anyway. >> >> > Cheers. >> >> > --ejw >> >> > Eric Woodward >> > Email: e...@nambu.com >
