Clarification on support for OAuth 1

No. Core API v1 will continue to work as-is.

Thanks for the response. I wasn't sure whether they would run alongside each other or not, so good to know.

Hi! Could you please confirm that Core API will continue to work with OAuth 1.0? A year has passed maybe something was changed, because v2 endpoints work only with OAuth 2.0. There is https://www.dropbox.com/developers-v1/core/docs#oa2-from-oa1 endpoint which provides a capability to work with v2 endpoints using OAuth 1.0 authorization flow. Can we be sure that after v1 endpoints are deprecated the OAuth 1.0 endpoints will work as before? Thanks in advance.

API v1, a.k.a. the Core API, supports both OAuth 1 and OAuth 2 and will continue to do so. Note that API v1 is already deprecated in favor of API v2.

API v2 only supports OAuth 2.

The /1/oauth2/token_from_oauth1 endpoint you mentioned allows you to get an OAuth 2 access token from an OAuth 1 access token. We recommend using that while API v1 is still enabled in order to migrate your existing users to API v2.

When you do migrate your app to API v2, you should also migrate to using the OAuth 2 app authorization flow itself in place of the OAuth 1 flow. 

Thanks for the quick response! Just to be sure that we are on the same page. Our application uses https://www.dropbox.com/1/oauth/authorize endpoint as a first step in the authorization flow. In the migration guide is mentioned that /1/oauth2/authorize endpoint is migrated to /oauth2/authorize. Does it mean that https://www.dropbox.com/1/oauth/authorize request won't work after Sept, 28 when v1 will be deprecated? Thanks again for help!

Yes, the OAuth 1 authorization page at /1/oauth/authorize is only for API v1, and will be retired with API v1. You'll need to migrate to using the OAuth 2 authorization page at /oauth2/authorize.

(API v2 doesn't support OAuth 1, so the OAuth 1 page won't be useful once API v1 is retired anyway.)