Dropbox .NET SDK (Refresh Token)

@GevorgMel This functionality should now be available on DropboxTeamClient as of release v5.1.0. Please update and give that a try and let us know if you run in to any issues. Thanks!

All comments

The Dropbox .NET SDK should automatically do the refresh for you, on every client creation and API call as needed.

If you do want to explicitly refresh though, e.g., to get an access token with fewer scopes, you should be able to use RefreshAccessToken to do so, as shown in the example here.

Let us know if something isn't working as expected though.

Thank you for the reply and link to RefreshAccessToken method. I found this method in DropboxClient. What about DropboxTeamClient, I need this client and accordingly to use access token which probably been expired. How I should handle this case?

I believe that's not currently implemented on DropboxTeamClient. I'll ask the team to add that there as well, but I can't promise a timeline for that. I'll follow up here once I have any update on that.

Thank you very much for great support and I will check this thread for further updates.

@GevorgMel This functionality should now be available on DropboxTeamClient as of release v5.1.0. Please update and give that a try and let us know if you run in to any issues. Thanks!

I understand, the Dropbox client can automatically refresh the refresh tokens if fed with the correct access token and refresh token.

But how can I retrieve the actual new access token and refresh token, to store it, for new instances of the DropboxClient?

@OFV The Dropbox client in the SDK can and will automatically handle the refresh for you, and you shouldn't even need to access to refresh token or new access token after a refresh. The refresh token doesn't change, and the client will automatically set its new access token. And if you need another client, you can just create it like you did originally and let the client handle the refresh again if needed.

Excellent! thanks

Greg, I still can't get it to work for a duration longer than the access token's validity.

(this part works:)

I ask for user authentication (only once) using the DropboxOAuth2Helper.GetAuthorizeUri with OAuthResponseType.Code and TokenAccessType.Offline.

The resulting POST http request gives me a code and DropboxOAuth2Helper.ProcessCodeFlowAsync provides me an access token and refresh token based on that code. The tokens are persisted in the DB and to be used for longer periods (months) without the user needing to re-login

(this part fails:)

The DropboxClient is instantiated with the Access_token and refresh token retrieved in the first part.

Using the DropboxClient.Files.ListFolderAsync it works for a while (a few hours after initial usser auth), but the next day it fails with "Dropbox.Api.AuthException: expired_access_token/"

It concerns an MVC webapp, and the dropboxclient is newly instantiated on every use.

I thought the DropboxClient would do "it's thing" using the initial access and refresh tokens.

(I am using the Official Dropbox .Net v2 SDK v5.5.0 Nuget package)

@OFV When your "DropboxClient is instantiated with the Access_token and refresh token", are you also supplying the app key and secret? Those are required to perform the refresh. Make sure you're doing so, like in the example here.

Yes I am using the appid and appsecret. I'm using the constructor as in the example, with the addition of the access token expiry date:

CurrentClient = new DropboxClient(accessToken, refreshToken, expiryDate, appKey, appSecret, config);

The access token returned starts with sl. and is 139 bytes long. The refresh token starts with 1y_ and is 64 bytes long.

Fetching data from the api works up to the expiry date, which was set to 2020-12-09 17:37:48. After that fetching data takes a few minutes (!!) before throwing the exception.

I found 2 possible culprits:

- My code wasn't properly "asynced", which I know I have to avoid: eg: ListFolderAsync(xxx).result(). I recursively converted all methods to async (which was a long way up), and got rid of the .result calls. (I know these calls result in timeouts when exceptions occur inside)

- In the Dropbox App console for our app, under OAuth section: The "access token expiration" was still set to "no expiration", which I now set to "short lived".

With these 2 updates, it now seems to run (with original accesss token still from yesterday).

Try to use a constructor with refreshtoken, appkey, appSecret. It works for me

Gevorg,

Thanks for the help, but it wroks for me now, even with the extra params in the constructor.

My issue was due to the 2 culprits I described in my previous post.

abeyaz

I am saving only the refresh token to database and using dropboxClient with refresh token, appkey, appsecret constructor. Do I need to save the access token also and use accessToken, refreshToken, appKey, appSecret, config constructor instead. What is the difference between them?

No, there is no need to save access token, if you’re using appId, appSecret and refresh token it is enough. Provided access token will be ignored anyway.

@abeyaz GevorgMel is correct, you do not need to supply the access token as well. That is optional, since only the refresh token, app key, and app secret are actually needed to perform the refresh to get a new short-lived access token.

abeyaz

Thank you. Documentation says refresh tokens are long-lived. How long exactly? Say it is 6 months, does it mean we need to involve client again to get a new authentication code and then a new refresh token ?

@abeyaz Refresh tokens don't expire by themselves, but they can be revoked on demand by the user/app.

jon p

I can't find any example of how to let the SDK take care of the token refreshing? I need to do this independently of user input.

Do I have to hit this method:

public DropboxClient(
string oauth2RefreshToken,
string appKey,
string appSecret,
DropboxClientConfig config
)

Do I use the same refresh token every time?