S3Transfer only supports files on disk, not Python file objects

There seems to be nothing to prevent S3Transfer to upload any object that supports read, seek, tell and size, so I would like to suggest an abstraction that receives a file object. e.g. the existing code would defer to new one that is more generic

def upload_file(self, filename, bucket, key,
                    callback=None, extra_args=None):
    self.upload_file_object(open(filename, 'r'), bucket, key,
                    callback=callback, extra_args=extra_args)

[hunt3ri]

+1 for me on this feature, it’s annoying have to write stream to disk when ideally I’d like to pass it straight thru to S3

[kyleknap]

The ability to upload files from file-like objects is now supported in boto3 1.4.0, I would recommend reading: https://boto3.readthedocs.io/en/latest/guide/s3.html#uploads and using one of the upload_fileobj() methods to upload file-like objects.

I also noticed that there were discussions of implementing OSUtils so it would be good to take a look at the upgrading notes: https://boto3.readthedocs.io/en/latest/guide/upgrading.html before upgrading as functionality may have changed based on assumptions made in custom implementations of OSUtils.

Otherwise, resolving issue as the functionality is now available.