Update backend.configuration() to use BackendConfiguration

CHANGELOG.rst

@@ -64,7 +64,10 @@ Changed
 - `IBMQ.save_account()` now takes an `overwrite` option to replace an existing
   account on disk. Default is False (#1295).
 - Backend and Provider methods defined in the specification use model objects
-  rather than dicts, along with validation against schemas (#1249, #1277).
+  rather than dicts, along with validation against schemas (#1249, #1277). The
+  updated methods include:
+    - ``backend.status()``(#1301).
+    - ``backend.configuration()`` (and ``__init__``) (#1323).
 - ``backend.provider()`` is now a method instead of a property (#1312).
 - Remove local backend (Aer) fallback (#1303)
 

qiskit/backends/aer/aerprovider.py

@@ -115,7 +115,7 @@ def _verify_aer_backends(self):
         for backend_cls in AER_STANDARD_BACKENDS:
             try:
                 backend_instance = self._get_backend_instance(backend_cls)
-                backend_name = backend_instance.configuration()['name']
+                backend_name = backend_instance.name()
                 ret[backend_name] = backend_instance
             except QISKitError as err:
                 # Ignore backends that could not be initialized.
@@ -132,8 +132,7 @@ def _get_backend_instance(self, backend_cls):
         Returns:
             BaseBackend: a backend instance.
         Raises:
-            QISKitError: if the backend could not be instantiated or does not
-                provide a valid configuration containing a name.
+            QISKitError: if the backend could not be instantiated.
         """
         # Verify that the backend can be instantiated.
         try:
@@ -142,12 +141,6 @@ def _get_backend_instance(self, backend_cls):
             raise QISKitError('Backend %s could not be instantiated: %s' %
                               (backend_cls, err))
 
-        # Verify that the instance has a minimal valid configuration.
-        try:
-            _ = backend_instance.configuration()['name']
-        except (LookupError, TypeError):
-            raise QISKitError('Backend %s has an invalid configuration')
-
         return backend_instance
 
     def __str__(self):

qiskit/backends/aer/qasm_simulator.py

@@ -20,6 +20,7 @@
 
 import numpy as np
 
+from qiskit.backends.models import BackendConfiguration
 from qiskit.result._utils import copy_qasm_from_qobj_into_result, result_from_old_style_dict
 from qiskit.backends import BaseBackend
 from qiskit.backends.aer.aerjob import AerJob
@@ -46,34 +47,40 @@ class QasmSimulator(BaseBackend):
     """C++ quantum circuit simulator with realistic noise"""
 
     DEFAULT_CONFIGURATION = {
-        'name': 'qasm_simulator',
+        'backend_name': 'qasm_simulator',
+        'backend_version': '1.0.0',
+        'n_qubits': -1,
         'url': 'https://github.com/QISKit/qiskit-terra/src/qasm-simulator-cpp',
         'simulator': True,
         'local': True,
-        'description': 'A C++ realistic noise simulator for qobj files',
-        'coupling_map': 'all-to-all',
-        "basis_gates": 'u0,u1,u2,u3,cx,cz,id,x,y,z,h,s,sdg,t,tdg,rzz,' +
-                       'snapshot,wait,noise,save,load'
+        'conditional': True,
+        'open_pulse': False,
+        'description': 'A C++ realistic noise simulator for qasm experiments',
+        'basis_gates': ['u0', 'u1', 'u2', 'u3', 'cx', 'cz', 'id', 'x', 'y', 'z',
+                        'h', 's', 'sdg', 't', 'tdg', 'rzz', 'snapshot', 'wait',
+                        'noise', 'save', 'load'],
+        'gates': [{'name': 'TODO', 'parameters': [], 'qasm_def': 'TODO'}]
     }
 
     def __init__(self, configuration=None, provider=None):
-        super().__init__(configuration=configuration or self.DEFAULT_CONFIGURATION.copy(),
+        super().__init__(configuration=(configuration or
+                                        BackendConfiguration.from_dict(self.DEFAULT_CONFIGURATION)),
                          provider=provider)
 
         # Try to use the default executable if not specified.
-        if self._configuration.get('exe'):
-            paths = [self._configuration.get('exe')]
+        if 'exe' in self._configuration:
+            paths = [self._configuration.exe]
         else:
             paths = DEFAULT_SIMULATOR_PATHS
 
         # Ensure that the executable is available.
         try:
-            self._configuration['exe'] = next(
+            self._configuration.exe = next(
                 path for path in paths if (os.path.exists(path) and
                                            os.path.getsize(path) > 100))
         except StopIteration:
             raise FileNotFoundError('Simulator executable not found (using %s)' %
-                                    self._configuration.get('exe', 'default locations'))
+                                    getattr(self._configuration, 'exe', 'default locations'))
 
     def run(self, qobj):
         """Run a qobj on the backend."""
@@ -84,7 +91,7 @@ def run(self, qobj):
 
     def _run_job(self, job_id, qobj):
         self._validate(qobj)
-        result = run(qobj, self._configuration['exe'])
+        result = run(qobj, self._configuration.exe)
         result['job_id'] = job_id
         copy_qasm_from_qobj_into_result(qobj, result)
 
@@ -104,33 +111,39 @@ class CliffordSimulator(BaseBackend):
     """"C++ Clifford circuit simulator with realistic noise."""
 
     DEFAULT_CONFIGURATION = {
-        'name': 'clifford_simulator',
-        'url': 'https://github.com/QISKit/qiskit-terra/src/qasm-simulator',
+        'backend_name': 'clifford_simulator',
+        'backend_version': '1.0.0',
+        'n_qubits': -1,
+        'url': 'https://github.com/QISKit/qiskit-terra/src/qasm-simulator-cpp',
         'simulator': True,
         'local': True,
+        'conditional': True,
+        'open_pulse': False,
         'description': 'A C++ Clifford simulator with approximate noise',
-        'coupling_map': 'all-to-all',
-        'basis_gates': 'cx,id,x,y,z,h,s,sdg,snapshot,wait,noise,save,load'
+        'basis_gates': ['cx', 'id', 'x', 'y', 'z', 'h', 's', 'sdg', 'snapshot',
+                        'wait', 'noise', 'save', 'load'],
+        'gates': [{'name': 'TODO', 'parameters': [], 'qasm_def': 'TODO'}]
     }
 
     def __init__(self, configuration=None, provider=None):
-        super().__init__(configuration=configuration or self.DEFAULT_CONFIGURATION.copy(),
+        super().__init__(configuration=(configuration or
+                                        BackendConfiguration.from_dict(self.DEFAULT_CONFIGURATION)),
                          provider=provider)
 
         # Try to use the default executable if not specified.
-        if self._configuration.get('exe'):
-            paths = [self._configuration.get('exe')]
+        if 'exe' in self._configuration:
+            paths = [self._configuration.exe]
         else:
             paths = DEFAULT_SIMULATOR_PATHS
 
         # Ensure that the executable is available.
         try:
-            self._configuration['exe'] = next(
+            self._configuration.exe = next(
                 path for path in paths if (os.path.exists(path) and
                                            os.path.getsize(path) > 100))
         except StopIteration:
             raise FileNotFoundError('Simulator executable not found (using %s)' %
-                                    self._configuration.get('exe', 'default locations'))
+                                    getattr(self._configuration, 'exe', 'default locations'))
 
     def run(self, qobj):
         """Run a Qobj on the backend.
@@ -159,7 +172,7 @@ def _run_job(self, job_id, qobj):
             qobj_dict['config'] = {'simulator': 'clifford'}
 
         qobj = Qobj.from_dict(qobj_dict)
-        result = run(qobj, self._configuration['exe'])
+        result = run(qobj, self._configuration.exe)
         result['job_id'] = job_id
 
         return result_from_old_style_dict(

qiskit/backends/aer/qasm_simulator_py.py

@@ -78,6 +78,7 @@
 
 import numpy as np
 
+from qiskit.backends.models import BackendConfiguration
 from qiskit.result._utils import copy_qasm_from_qobj_into_result, result_from_old_style_dict
 from qiskit.backends import BaseBackend
 from qiskit.backends.aer.aerjob import AerJob
@@ -90,17 +91,22 @@ class QasmSimulatorPy(BaseBackend):
     """Python implementation of a qasm simulator."""
 
     DEFAULT_CONFIGURATION = {
-        'name': 'qasm_simulator_py',
+        'backend_name': 'qasm_simulator_py',
+        'backend_version': '2.0.0',
+        'n_qubits': -1,
         'url': 'https://github.com/QISKit/qiskit-terra',
         'simulator': True,
         'local': True,
-        'description': 'A python simulator for qasm files',
-        'coupling_map': 'all-to-all',
-        'basis_gates': 'u1,u2,u3,cx,id,snapshot'
+        'conditional': True,
+        'open_pulse': False,
+        'description': 'A python simulator for qasm experiments',
+        'basis_gates': ['u1', 'u2', 'u3', 'cx', 'id', 'snapshot'],
+        'gates': [{'name': 'TODO', 'parameters': [], 'qasm_def': 'TODO'}]
     }
 
     def __init__(self, configuration=None, provider=None):
-        super().__init__(configuration=configuration or self.DEFAULT_CONFIGURATION.copy(),
+        super().__init__(configuration=(configuration or
+                                        BackendConfiguration.from_dict(self.DEFAULT_CONFIGURATION)),
                          provider=provider)
 
         self._local_random = random.Random()
@@ -243,7 +249,7 @@ def _run_job(self, job_id, qobj):
         for circuit in qobj.experiments:
             result_list.append(self.run_circuit(circuit))
         end = time.time()
-        result = {'backend': self._configuration['name'],
+        result = {'backend': self.name(),
                   'id': qobj.qobj_id,
                   'job_id': job_id,
                   'result': result_list,
@@ -342,7 +348,7 @@ def run_circuit(self, circuit):
                     params = operation.params
                     self._add_qasm_snapshot(params[0])
                 else:
-                    backend = self._configuration['name']
+                    backend = self.name()
                     err_msg = '{0} encountered unrecognized operation "{1}"'
                     raise SimulatorError(err_msg.format(backend,
                                                         operation.name))

qiskit/backends/aer/statevector_simulator.py

@@ -14,6 +14,7 @@
 import logging
 import uuid
 
+from qiskit.backends.models import BackendConfiguration
 from qiskit.qobj import QobjInstruction
 from .qasm_simulator import QasmSimulator
 from ._simulatorerror import SimulatorError
@@ -26,17 +27,24 @@ class StatevectorSimulator(QasmSimulator):
     """C++ statevector simulator"""
 
     DEFAULT_CONFIGURATION = {
-        'name': 'statevector_simulator',
+        'backend_name': 'statevector_simulator',
+        'backend_version': '1.0.0',
+        'n_qubits': -1,
         'url': 'https://github.com/QISKit/qiskit-terra/src/qasm-simulator-cpp',
         'simulator': True,
         'local': True,
-        'description': 'A C++ statevector simulator for qobj files',
-        'coupling_map': 'all-to-all',
-        'basis_gates': 'u1,u2,u3,cx,cz,id,x,y,z,h,s,sdg,t,tdg,rzz,load,save,snapshot'
+        'conditional': False,
+        'open_pulse': False,
+        'description': 'A single-shot C++ statevector simulator for the |0> state evolution',
+        'basis_gates': ['u1', 'u2', 'u3', 'cx', 'cz', 'id', 'x', 'y', 'z', 'h',
+                        's', 'sdg', 't', 'tdg', 'rzz', 'load', 'save',
+                        'snapshot'],
+        'gates': [{'name': 'TODO', 'parameters': [], 'qasm_def': 'TODO'}]
     }
 
     def __init__(self, configuration=None, provider=None):
-        super().__init__(configuration=configuration or self.DEFAULT_CONFIGURATION.copy(),
+        super().__init__(configuration=(configuration or
+                                        BackendConfiguration.from_dict(self.DEFAULT_CONFIGURATION)),
                          provider=provider)
 
     def run(self, qobj):

qiskit/backends/aer/statevector_simulator_py.py

@@ -23,6 +23,7 @@
 
 from qiskit.backends.aer.aerjob import AerJob
 from qiskit.backends.aer._simulatorerror import SimulatorError
+from qiskit.backends.models import BackendConfiguration
 from qiskit.qobj import QobjInstruction
 from .qasm_simulator_py import QasmSimulatorPy
 
@@ -33,17 +34,22 @@ class StatevectorSimulatorPy(QasmSimulatorPy):
     """Python statevector simulator."""
 
     DEFAULT_CONFIGURATION = {
-        'name': 'statevector_simulator_py',
+        'backend_name': 'statevector_simulator_py',
+        'backend_version': '1.0.0',
+        'n_qubits': -1,
         'url': 'https://github.com/QISKit/qiskit-terra',
         'simulator': True,
         'local': True,
+        'conditional': False,
+        'open_pulse': False,
         'description': 'A Python statevector simulator for qobj files',
-        'coupling_map': 'all-to-all',
-        'basis_gates': 'u1,u2,u3,cx,id,snapshot'
+        'basis_gates': ['u1', 'u2', 'u3', 'cx', 'id', 'snapshot'],
+        'gates': [{'name': 'TODO', 'parameters': [], 'qasm_def': 'TODO'}]
     }
 
     def __init__(self, configuration=None, provider=None):
-        super().__init__(configuration=configuration or self.DEFAULT_CONFIGURATION.copy(),
+        super().__init__(configuration=(configuration or
+                                        BackendConfiguration.from_dict(self.DEFAULT_CONFIGURATION)),
                          provider=provider)
 
     def run(self, qobj):

qiskit/backends/aer/unitary_simulator_py.py

@@ -86,6 +86,7 @@
 
 import numpy as np
 
+from qiskit.backends.models import BackendConfiguration
 from qiskit.result._utils import copy_qasm_from_qobj_into_result, result_from_old_style_dict
 from qiskit.backends import BaseBackend
 from qiskit.backends.aer.aerjob import AerJob
@@ -103,17 +104,22 @@ class UnitarySimulatorPy(BaseBackend):
     """Python implementation of a unitary simulator."""
 
     DEFAULT_CONFIGURATION = {
-        'name': 'unitary_simulator_py',
+        'backend_name': 'unitary_simulator_py',
+        'backend_version': '1.0.0',
+        'n_qubits': -1,
         'url': 'https://github.com/QISKit/qiskit-terra',
         'simulator': True,
         'local': True,
-        'description': 'A python simulator for unitary matrix',
-        'coupling_map': 'all-to-all',
-        'basis_gates': 'u1,u2,u3,cx,id'
+        'conditional': False,
+        'open_pulse': False,
+        'description': 'A python simulator for unitary matrix corresponding to a circuit',
+        'basis_gates': ['u1', 'u2', 'u3', 'cx', 'id'],
+        'gates': [{'name': 'TODO', 'parameters': [], 'qasm_def': 'TODO'}]
     }
 
     def __init__(self, configuration=None, provider=None):
-        super().__init__(configuration=configuration or self.DEFAULT_CONFIGURATION.copy(),
+        super().__init__(configuration=(configuration or
+                                        BackendConfiguration.from_dict(self.DEFAULT_CONFIGURATION)),
                          provider=provider)
 
         # Define attributes inside __init__.
@@ -189,7 +195,7 @@ def _run_job(self, job_id, qobj):
         for circuit in qobj.experiments:
             result_list.append(self.run_circuit(circuit))
         end = time.time()
-        result = {'backend': self._configuration['name'],
+        result = {'backend': self.name(),
                   'id': qobj.qobj_id,
                   'job_id': job_id,
                   'result': result_list,

qiskit/backends/basebackend.py

@@ -28,15 +28,13 @@ def __init__(self, configuration, provider=None):
         not available.
 
         Args:
-            configuration (dict): configuration dictionary
+            configuration (BackendConfiguration): backend configuration
             provider (BaseProvider): provider responsible for this backend
 
         Raises:
             FileNotFoundError if backend executable is not available.
             QISKitError: if there is no name in the configuration
         """
-        if 'name' not in configuration:
-            raise qiskit.QISKitError('backend does not have a name.')
         self._configuration = configuration
         self._provider = provider
 
@@ -46,7 +44,11 @@ def run(self, qobj):
         pass
 
     def configuration(self):
-        """Return backend configuration"""
+        """Return the backend configuration.
+
+        Returns:
+            BackendConfiguration: the configuration fot the backend.
+        """
         return self._configuration
 
     def properties(self):
@@ -57,7 +59,7 @@ def provider(self):
         """Return the backend Provider.
 
         Returns:
-            BaseProvider: the Provider responsible for this backend.
+            BaseProvider: the Provider responsible for the backend.
         """
         return self._provider
 
@@ -74,8 +76,12 @@ def status(self):
                              status_msg='')
 
     def name(self):
-        """Return backend name"""
-        return self._configuration['name']
+        """Return backend name.
+
+        Returns:
+            str: the name of the backend.
+        """
+        return self._configuration.backend_name
 
     def __str__(self):
         return self.name()