Programatically generate auth token for nodejs server with javascript SDK

It's not possible to programmatically generate an access token without first using the OAuth app authorization flow, such as just from the app key and secret. The app authorization flow only needs to be done once per account though.

For reference, Dropbox is no longer offering the option for creating new long-lived access tokens. Dropbox is now issuing short-lived access tokens (and optional refresh tokens) instead of long-lived access tokens. You can find more information on this migration here.

Apps can still get long-term access by requesting "offline" access though, in which case the app receives a "refresh token" that can be used to retrieve new short-lived access tokens as needed, without further manual user intervention. You can find more information in the OAuth Guide and authorization documentation. There's a basic outline of processing this flow in this blog post which may serve as a useful example. (The "Generate" button on the app's page on the App Console can only be used to retrieve access tokens, not refresh tokens. You need to use the OAuth app authorization flow to get a refresh token.)

Here's an example of requesting offline access with the official Dropbox JavaScript SDK, which we recommend using. As long as you set the app key (a.k.a. client ID) and refresh token, like shown here in the example the SDK will actually handle refresh process for you automatically. The SDK will automatically catch expired access token errors and call the API to get a new short-lived access token when needed.