@chiarazampolli : This documentation change gives a summary of what is currently already implemented concerning your requests.

Let me comment further, using your use-cases:

a) "we should be able to have an automatic way to read whatever object is
in a file or in a CCDB repository without knowing a priori what the
object is, and then put this object in the CCDB":

This is achieved when reading from TFile. Further generalization straightforward.
For instance, generic upload of any object is implemented.

b) "when putting the CCDB entry reading it from file, all metadata should
be transferred to the CCDB too":

Not yet done but straightforward.

c) "when downloading a file from the CCDB, the file should contain not
just the object, but also its metadata; we said that this will be
possible only when downloading with the C++ api, not the REST api":

Done

d) "It would be good to have an example on how to cast an unknown CCDB
object to the correct type in an automatic way":

Automatic as in a script? I still don't see the use-case for this as casting to the concrete type
is only necessary when you want to call a member function on the object. This means you already have an idea of the function to call ... in which case you probably know the type in advance and can use the strongly-typed API. So I would appreciate a more concrete feature-request.

e) "Supposing to download (in files) two objects from the same path, we
need that the names of the files give us some information of what is
different.":

Not yet done but this can be easily added as an option to the download tool.

Just documentation. Merging.