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Dropbox authentication on iPhone X
My App's Dropbox authentication is failing on iPhone X and iOS 11. I still do not know the root cause and am just doing an initial inquiry here to learn if there is a known issue. What I can say is ...
- Thanks for digging in and tracking this down already! I'm glad to hear you figured this out. Calling authorizeFromController twice would indeed cause this. Enforcing a single call is the right thing to do given the unexpected viewDidAppear behavior.
Wasn't finished with last post, continuing:
I assume the real problem is that extractfromDAuthURL:url is called twice and thus the stored nonce doesn't match the current nonce. Also, I munged the redaction in the log entries previously, so here they are again.
2017-11-11 17:32:29.380496-0500 Krypton[3454:894607] DBSDKReachability Flag Status: -R ------- networkStatusForFlags 2017-11-11 17:32:30.189937-0500 Krypton[3454:894607] didEnterBackground 2017-11-11 17:32:30.205156-0500 Krypton[3454:894607] DBSDKReachability Flag Status: -R ------- networkStatusForFlags 2017-11-11 17:32:30.532935-0500 Krypton[3454:894607] [Snapshotting] Snapshotting a view (0x104005c00, UIKeyboardImpl) that is not in a visible window requires afterScreenUpdates:YES. 2017-11-11 17:32:31.573593-0500 Krypton[3454:894607] willEnterForeground 2017-11-11 17:32:31.590287-0500 Krypton[3454:894607] in viewwillappear call randomizecombination 2017-11-11 17:32:31.646979-0500 Krypton[3454:894607] handling URL: db-***://1/connect?oauth_token_secret=***&state=oauth2%3A9C3186A0-0DAF-48F3-8D70-F98E86DBE839&uid=***&oauth_token=oauth2%3A 2017-11-11 17:32:31.647129-0500 Krypton[3454:894607] stored nonce: 9B60EAE8-003D-40D6-AEF7-4BC8620372C8 2017-11-11 17:32:31.647267-0500 Krypton[3454:894607] Auth Error: Error:[ErrorType: 6 ErrorDescription: Unable to verify link request.] 2017-11-11 17:32:31.648096-0500 Krypton[3454:894607] handling URL: db-***://1/connect?oauth_token_secret=***&state=oauth2%3A9C3186A0-0DAF-48F3-8D70-F98E86DBE839&uid=***&oauth_token=oauth2%3A 2017-11-11 17:32:31.648217-0500 Krypton[3454:894607] stored nonce: 9B60EAE8-003D-40D6-AEF7-4BC8620372C8 2017-11-11 17:32:31.648301-0500 Krypton[3454:894607] Auth Error: Error:[ErrorType: 6 ErrorDescription: Unable to verify link request.]
Thus we see that the stored nonce is not the same as what's presented in the URL. This is on iPhone X only, on iPad Air 2 those data match and authentication succeeds. I will continue to see if I've broken my own code with iPhone X mods, but it's not obvious that they could have any impact ... famous last words, eh?!
Again, I see the log message DBSDKReachability twice for iPhone X but once for iPad. I also see the call to extractfromDAuthURL:url twice for iPhone X but only once for iPad.
And NOW I figured it out: for iPhone X I am calling authorizeFromController:controller:openURL twice! When I artificially limit the call to just once authentication works. The call in inside viewDidAppear:animated. For iPad the view must not disappear when the Dropbox App is run, but for iPhone X there is a second call to viewDidAppear:animated which I do not understand.
Now off to grok some more on what to do ....
Thanks!
Greg-DB
Dropbox Staff
Dropbox StaffThanks for digging in and tracking this down already! I'm glad to hear you figured this out. Calling authorizeFromController twice would indeed cause this. Enforcing a single call is the right thing to do given the unexpected viewDidAppear behavior.
I've restructured the Dropbox authentication flow slightly in light of the iPhone / iPad differences I found. I’ve used Dropbox in this App since 2011, so I’m surprised I didn’t see this issue earlier, although I must note that the viewDidAppear:animated code was added 2017.05.22 - this was my great API 1 --> API 2 commit! This Dropbox App vs. Dropbox web authentication issue might have really existed for the last 6 months and I never noticed it. I’ll have a definitive answer whenever I can borrow a non-iPhone X and see if viewDidAppear:animated is invoked once or twice.
Thanks again for your help.
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