Dirac-Rucio integration - upload/download with REST

[martynia]

This PR contains a draft of a Rucio File Catalog plugin which uses REST interface provided by the Rucio server. The Rucio client python bindings only contain operations required by RucioFileCatalogClient plugin to perform synchronous upload/download and listing operations. The clients:

• use X509 authentication only
• the configuration is entirely stored in the Dirac CS (a proxy location, CA location, VO, Dirac username/Rucio account and Rucio hosts URLs)

A need of a Rucio config file and environment variables which are commonly used to configure Rucio client is eliminated.

[cserf]

Just one first comment before reading the code in more details. The file into Resources/Catalog/RucioRESTClientApi are largely a copy and paste of the files into https://github.com/rucio/rucio/tree/master/lib/rucio/client . This is allowed by the Apache license I think (@bari12 should confirm), but at least the copyright cannot be dropped.

[bari12]

Hi,
Correct, it is allowed to copy&modify the code under Apache2.0 license, but the license/copyright notice should be kept.
It would be good though (Although not strictly required) to link back where the code came from and maybe keep the list of original authors.
Cheers, Martin

[martynia]

I added the licence, lists of original authors and a link to the original code. Is it how you wanted this to be @bari12 ?

[bari12]

Perfect 👍 , thanks a lot @martynia