There is a powerful open source tool for managing object storage called s3cmd. It is available from https://s3tools.org/s3cmd and was originally written for managing object storage data using S3. It is compatible with Catalyst Cloud object storage using the OpenStack S3 API.
While it is compatible, you do need to ensure that you specify the appropriate authentication details by customizing the s3cmd configuration file.
The following changes need to be specified in the .s3cfg file. You can select the appropriate API endpoint from the API page.
host_base = object-storage.nz-por-1.catalystcloud.io:443
host_bucket = object-storage.nz-por-1.catalystcloud.io:443
If you are on an older version of s3cmd, you may need to force the use of signature v2. To do this edit your .s3cfg file, and set:
signature_v2 = True