Generic error message when registering snap names longer than allowed

[Celso Providelo]

The current response from the (staging) Store API does not comply with the existing error pattern (particularly, top-level "code" attribute is empty):

{{{
$ snapcraft staging servers> PYTHONPATH=. ./snapcraft/main.py register name-tooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo-long -d
Starting snapcraft 2.28 from ./snapcraft.
Registering name-tooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo-long.
Starting new HTTPS connection (1): myapps.developer.staging.ubuntu.com
"POST /dev/api/register-name/ HTTP/1.1" 400 None
==============================
{'detail': 'Submitted data is not valid.', 'title': 'Invalid request.', 'invalid_params': [{'code': '', 'reason': 'The name name-tooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo-long should not be longer than 40 characters.', 'name': 'snap_name'}], 'status': 400, 'error_list': [{'code': '', 'extra': {'name': 'snap_name'}, 'message': 'The name name-tooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo-long should not be longer than 40 characters.'}], 'type': 'devportal:v1:request-invalid'}
==============================
Traceback (most recent call last):
  File "./snapcraft/main.py", line 381, in <module>
    main() # pragma: no cover
  File "./snapcraft/main.py", line 253, in main
    return run(args, project_options)
  File "./snapcraft/main.py", line 297, in run
    _run_store_command(args)
  File "./snapcraft/main.py", line 347, in _run_store_command
    snapcraft.register(args['<snap-name>'], args['--private'])
  File "/home/cprov/Canonical/snappy/snapcraft/snapcraft/_store.py", line 327, in register
    store.register(snap_name, is_private)
  File "/home/cprov/Canonical/snappy/snapcraft/snapcraft/storeapi/__init__.py", line 200, in register
    self.sca.register, snap_name, is_private, constants.DEFAULT_SERIES)
  File "/home/cprov/Canonical/snappy/snapcraft/snapcraft/storeapi/__init__.py", line 183, in _refresh_if_necessary
    return func(*args, **kwargs)
  File "/home/cprov/Canonical/snappy/snapcraft/snapcraft/storeapi/__init__.py", line 535, in register
    raise errors.StoreRegistrationError(snap_name, response)
snapcraft.storeapi.errors.StoreRegistrationError: Registration failed.
}}}

Obs: error response printed with locally patched snapcraft.

[Celso Providelo (cprov)]

Partial snapcraft PR in https://github.com/snapcore/snapcraft/pull/1247

[Facundo Batista (facundo)]

Confirmed that SCA now returns the 'code' field not empty:

{'detail': 'Submitted data is not valid.',
 'error_list': [{'code': 'invalid',
                 'extra': {'name': 'snap_name'},
                 'message': 'The name '
                            'jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj '
                            'should not be longer than 40 characters.'}],
 'invalid_params': [{'code': 'invalid',
                     'name': 'snap_name',
                     'reason': 'The name '
                               'jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj '
                               'should not be longer than 40 characters.'}],
 'status': 400,
 'title': 'Invalid request.',
 'type': 'devportal:v1:request-invalid'}