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Getting invalid request for PKCEOAuthFlow.ProcessCodeFlowAsync
Hi, I'm implementing PKCE now, but getting an invalid request exception. I can't see anything that I'm doing wrong from the doco (it says everything is optional except code and appkey). This i...
donaldp wrote:...
And the doco states that step is optional, as I already said. ...
Probably we are talking for different things. How constructing URL used on launching the browser (where you are getting code) can be optional? You are getting such code every time OAuth is on go, but it's optional... 🤔 Can you clarify the meaning of word "optional" here (in this context)?
This is something mandatory for any type of Flow in use and both with and without redirection! Sometimes it's simple, sometimes little bit complicated. When SDK is in use you are relying on the SDK code to do this, should look the same. Just careful what code is used to construct it. Don't mix different code (from different flows) together.
One more thing:
donaldp wrote:... (I already asked if there's a different URL needed to be used for the PKCE flow - I'm using the same URL as non-PKCE flow, but maybe that's the issue?).
What actually means "the same URL"? If you mean URL received using the same code (PKCEOAuthFlow class code), that's correct. Since this URL will contain within code challenge (something supposed to be unique for every query), URL literal gonna be different. If you mean usage of a constant URL literal..., where and how will come code challenge from - something mandatory for PKCE?
From https://developers.dropbox.com/oauth-guide - "The redirect_uri is optional with the code flow - if unspecified, the authorization code is displayed on dropbox.com for the user to copy and paste to your app"
So the URL is https://www.dropbox.com/oauth2/authorize?client_id=MY_CLIENT_ID&redirect_uri=MY_REDIRECT_URI&response_type=code, but without the redirect, since that is optional, and that link is always the same, so just have a browser shortcut for it.
It sounds like the link is different for PKCE then?
Yes, we are talking for different things. donaldp, It's correct:
donaldp wrote:From https://developers.dropbox.com/oauth-guide - "The redirect_uri is optional with the code flow - if unspecified, the authorization code is displayed on dropbox.com for the user to copy and paste to your app"
...
But the following:
donaldp wrote:...
So the URL is https://www.dropbox.com/oauth2/authorize?client_id=MY_CLIENT_ID&redirect_uri=MY_REDIRECT_URI&response_type=code, ...
... is definitely NOT "redirect_url"!!! It's the URL used to launch the authentication and it's mandatory for every Flow - no way to get anything without it! Again, PKCE Flow does suppose code challenge existance... no, no just does suppose - it's mandatory and will never work without.
Take a look here and look on PKCE example (scroll little down). See there what's mandatory and what - not. Better don't construct it by hand, but use corresponding method instead.
Ok, used the wrong name - it's the authorisation URL, not the redirect URL - but it's still the same URL every time. The link you provided says the same thing -
https://www.dropbox.com/oauth2/authorize?client_id=<APP_KEY>&response_type=code
- so I still don't know why it's not working, given that's exactly the URL I've been using.
OMG...
Documentation:Example: Auth URL for PKCE code flow
https://www.dropbox.com/oauth2/authorize?client_id=<APP_KEY>&response_type=code&code_challenge=<CHALLENGE>&code_challenge_method=<METHOD>
Be more careful, where you are looking on!
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