Use with Digital Ocean Spaces?

[nickian]

It looks like this works with a custom endpoint, but I'm not sure how to get Digital Ocean's Spaces to work. This is what my config.php file looks like:

define('AWS_KEY', 'my-key');
define('AWS_SECRET', 'my-secret');
define('AWS_S3_BUCKET', 'my-bucket-name');
define('AWS_S3_PREFIX', '');
define('AWS_S3_REGION', 'sfo2');
define('AWS_S3_OPTIONS', json_encode([
    'version' => 'latest', 
    'endpoint' => 'sfo2.digitaloceanspace.com', 
    'use_path_style_endpoint' => true
]));

But I get this error when I try to attach a document to a task:

Unable to upload files, check the permissions of your data folder.

Do I have the config set up correctly, or am I missing something?