# -*- coding: utf-8 -*-
# This code is part of Qiskit.
#
# (C) Copyright IBM 2017, 2018.
#
# This code is licensed under the Apache License, Version 2.0. You may
# obtain a copy of this license in the LICENSE.txt file in the root directory
# of this source tree or at http://www.apache.org/licenses/LICENSE-2.0.
#
# Any modifications or derivative works of this code must retain this
# copyright notice, and modified files need to carry a notice indicating
# that they have been altered from the originals.
"""Base class for a backend provider."""
from abc import ABC, abstractmethod
from .exceptions import QiskitBackendNotFoundError
[docs]class BaseProvider(ABC):
"""Base class for a Backend Provider."""
def __init__(self, *args, **kwargs):
pass
[docs] def get_backend(self, name=None, **kwargs):
"""Return a single backend matching the specified filtering.
Args:
name (str): name of the backend.
**kwargs: dict used for filtering.
Returns:
BaseBackend: a backend matching the filtering.
Raises:
QiskitBackendNotFoundError: if no backend could be found or
more than one backend matches the filtering criteria.
"""
backends = self.backends(name, **kwargs)
if len(backends) > 1:
raise QiskitBackendNotFoundError('More than one backend matches the criteria')
if not backends:
raise QiskitBackendNotFoundError('No backend matches the criteria')
return backends[0]
[docs] @abstractmethod
def backends(self, name=None, **kwargs):
"""Return a list of backends matching the specified filtering.
Args:
name (str): name of the backend.
**kwargs: dict used for filtering.
Returns:
list[BaseBackend]: a list of Backends that match the filtering
criteria.
"""
pass
def __eq__(self, other):
"""Equality comparison.
By default, it is assumed that two `Providers` from the same class are
equal. Subclassed providers can override this behavior.
"""
return type(self).__name__ == type(other).__name__