[Netconf] restconf and namespaces and unique module names.

[Kent Watsen <[e-mail]>]

My issue is with RESTCONF, but the concern extends to YANG and JSON
encoding as well.

YANG's namespace statement is intended to make module names unique.
While IETF-defined modules tend to have a unique namespace per module (why
is that?), this is not required and I wonder if it will interfere with our
module-structure aspirations.

But back to my concern, RESTCONF's URL-encoding uses module names (not
namespace) as a prefix to uniquely identify the module and yet there is no
guarantee that the module names are unique.  For instance:

  module system {
    namespace "http://vendor-foo.com";
    leaf hostname {
      type string;
    }
  }


  module system {
    namespace "http://openconfig.net";  <--- using OC just to make a point
    leaf hostname {
      type string;
    }
  }



And then we have the RESTCONF call:

  GET https://<server>/data/system:hostname HTTP/1.1


So which module is used?  Is this an error condition?  - do we need a
statement that no two modules can have the same name?  Should we use YANG
library to provide an alternate module-name (e.g., system-1) for when
collisions occur?


Thanks,
Kent