API limits on RPC endpoints

rk90

As per the Dropbox API doc, there limits to the API calls, but Dropbox does not wish to disclose any info on limitations.

I understand that there might be daily/monthly quota on upload/download APIs, but what are the limitations on RPC endpoints?  The reason I ask this is because, I will be doing a complete scan of pretty large Dropbox Business accounts (Thousands of members with millions of folders). Listing each folder at a time will be very time consuming and may even take days, so I plan to list multiple folders simulataneously and wanted to take advice on limits on number of concurrent list_folder requests. I ran a few tests and the behaviour was inconsistent. That is, at times I was able to list 10 folders concurrently while other times I get '429 too many requests' when trying to list 3 folders concurrently.

Greg-DB

The Dropbox API does have a rate limiting system, but we don't have any specific numbers documented. For reference though, the limits operate on a per-user basis. 

However, note that not all 429s and 503s indicate explicit rate limiting, but in any case that you get a 429 or 503 the best practice is to retry the request, respecting the Retry-After header if given in the response, or using an exponential back-off, if not. (Generally the window isn't more than a few minutes.) The rate limiting system and parameters are subject to change, so this strategy is preferred as it produces a more dynamic way of handling rate limiting, as opposed to relying on a hard-coded number. You should also check the response body for a specific error message.

There are also some special cases that can produce rate limiting responses without excessive amounts of calls. For instance, with list_folder, some of the special cases that you might encounter:

• If certain file metadata is not yet available at the time of the API call (e.g., for new files), you'll get a 429 and will need to call back after the (generally very short, on the order of seconds) delay indicated in the Retry-After header.
• If you make multiple identical /2/files/list_folder[/continue] calls simultaneously (e.g., for the same user and folder), you'll get a 429 back. For those, avoid sending the duplicate calls.