We have a collection that has a KinveyFile reference. We noticed that immediately after saving an entity with a file, the object passed into the success callback does not have a _downloadURL. Our guess is that the file upload has not been completed. Is there a way we can get notified (e.g. a service hook?) when the actual file is successfully uploaded and ready for download?

First, are you saving your entity through a business logic script? if so, you should be aware that KinveyFile references are only resolved when using the Data Store API (either using REST or one of our libraries).



As for your second question-- because the file itself is uploaded directly to Google Cloud Storage, and does not pass through Kinvey, we cannot offer a way to notify you of a successful upload. Depending on how you upload your files, you should be able to build your own notification system (for example, you could create a custom endpoint that accepts a file ID and sets a "successfullyUploaded" flag in that file's entity on Kinvey. Your upload code could then hit this endpoint when the upload is complete).