Add account management functionality

.pylintrc

@@ -292,7 +292,7 @@ indent-after-paren=4
 indent-string='    '
 
 # Maximum number of characters on a single line.
-max-line-length=105
+max-line-length=120
 
 # Maximum number of lines in a module.
 max-module-lines=1000

qiskit_ibm_runtime/accounts/__init__.py

@@ -0,0 +1,18 @@
+# This code is part of Qiskit.
+#
+# (C) Copyright IBM 2021.
+#
+# 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.
+
+"""
+Account management functionality related to the IBM Runtime Services.
+"""
+
+from .account import Account, AccountType
+from .management import AccountManager

qiskit_ibm_runtime/accounts/account.py

@@ -0,0 +1,102 @@
+# This code is part of Qiskit.
+#
+# (C) Copyright IBM 2021.
+#
+# 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.
+
+"""Account related classes and functions."""
+
+
+from typing import Optional
+from urllib.parse import urlparse
+
+from typing_extensions import Literal
+
+AccountType = Optional[Literal["cloud", "legacy"]]
+
+LEGACY_API_URL = "https://auth.quantum-computing.ibm.com/api"
+CLOUD_API_URL = "https://cloud.ibm.com"
+
+
+def _assert_valid_auth(auth: AccountType) -> None:
+    """Assert that the auth parameter is valid."""
+    if not (auth in ["cloud", "legacy"]):
+        raise ValueError(
+            f"Inappropriate `auth` value. Expected one of ['cloud', 'legacy'], got '{auth}'."
+        )
+
+
+def _assert_valid_token(token: str) -> None:
+    """Assert that the token is valid."""
+    if not (isinstance(token, str) and len(token) > 0):
+        raise ValueError(
+            f"Inappropriate `token` value. Expected a non-empty string, got '{token}'."
+        )
+
+
+def _assert_valid_url(url: str) -> None:
+    """Assert that the URL is valid."""
+    try:
+        urlparse(url)
+    except:
+        raise ValueError(f"Inappropriate `url` value. Failed to parse '{url}' as URL.")
+
+
+def _assert_valid_instance(auth: AccountType, instance: str) -> None:
+    """Assert that the instance name is valid for the given account type."""
+    if auth == "cloud":
+        if not (isinstance(instance, str) and len(instance) > 0):
+            raise ValueError(
+                f"Inappropriate `instance` value. Expected a non-empty string."
+            )
+
+
+class Account:
+    """Class that represents an account."""
+
+    def __init__(
+        self,
+        auth: AccountType,
+        token: str,
+        url: Optional[str],
+        instance: Optional[str] = None,
+        proxies: Optional[dict] = None,
+        verify: Optional[bool] = True,
+    ):
+        """Account constructor."""
+        _assert_valid_auth(auth)
+        self.auth = auth
+
+        _assert_valid_token(token)
+        self.token = token
+
+        resolved_url = url or LEGACY_API_URL if auth == "legacy" else CLOUD_API_URL
+        _assert_valid_url(resolved_url)
+        self.url = resolved_url
+
+        _assert_valid_instance(auth, instance)
+        self.instance = instance
+        self.proxies = proxies
+        self.verify = verify
+
+    def to_saved_format(self) -> dict:
+        """Returns a dictionary that represents how the account is saved on disk."""
+        return {k: v for k, v in self.__dict__.items() if v is not None}
+
+    @classmethod
+    def from_saved_format(cls, data: dict) -> "Account":
+        """Creates an account instance from data saved on disk."""
+        return cls(
+            auth=data.get("auth"),
+            url=data.get("url"),
+            token=data.get("token"),
+            instance=data.get("instance"),
+            proxies=data.get("proxies"),
+            verify=data.get("verify"),
+        )

qiskit_ibm_runtime/accounts/exceptions.py

@@ -0,0 +1,19 @@
+# This code is part of Qiskit.
+#
+# (C) Copyright IBM 2021.
+#
+# 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.
+
+"""Exceptions for the ``Accounts`` module."""
+
+from ..exceptions import IBMError
+
+
+class AccountsError(IBMError):
+    """Base class for errors raised during account management."""

qiskit_ibm_runtime/accounts/management.py

@@ -0,0 +1,71 @@
+# This code is part of Qiskit.
+#
+# (C) Copyright IBM 2021.
+#
+# 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.
+
+"""Account management related classes and functions."""
+
+import os
+from typing import Optional, Union
+
+from .account import Account, AccountType
+from .storage import save_config, read_config, delete_config
+
+_DEFAULT_ACCOUNG_CONFIG_JSON_FILE = os.path.join(
+    os.path.expanduser("~"), ".qiskit", "qiskit-ibm.json"
+)
+_DEFAULT_ACCOUNT_NAME = "default"
+
+
+class AccountManager:
+    """Class that bundles account management related functionality."""
+
+    @staticmethod
+    def save(
+        token: Optional[str] = None,
+        url: Optional[str] = None,
+        instance: Optional[str] = None,
+        auth: Optional[AccountType] = None,
+        name: Optional[str] = _DEFAULT_ACCOUNT_NAME,
+        proxies: Optional[dict] = None,
+        verify: Optional[bool] = None,
+    ) -> None:
+        """Save account on disk."""
+
+        return save_config(
+            filename=_DEFAULT_ACCOUNG_CONFIG_JSON_FILE,
+            name=name,
+            config=Account(
+                token=token,
+                url=url,
+                instance=instance,
+                auth=auth,
+                proxies=proxies,
+                verify=verify,
+            ).to_saved_format(),
+        )
+
+    @staticmethod
+    def list() -> Union[dict, None]:
+        """List all accounts saved on disk."""
+
+        return read_config(filename=_DEFAULT_ACCOUNG_CONFIG_JSON_FILE)
+
+    @staticmethod
+    def get(name: Optional[str] = _DEFAULT_ACCOUNT_NAME) -> Account:
+        """Read account from disk."""
+        return Account.from_saved_format(
+            read_config(filename=_DEFAULT_ACCOUNG_CONFIG_JSON_FILE, name=name)
+        )
+
+    @staticmethod
+    def delete(name: Optional[str] = _DEFAULT_ACCOUNT_NAME) -> bool:
+        """Read account from disk."""
+        return delete_config(name=name, filename=_DEFAULT_ACCOUNG_CONFIG_JSON_FILE)

qiskit_ibm_runtime/accounts/storage.py

@@ -0,0 +1,82 @@
+# This code is part of Qiskit.
+#
+# (C) Copyright IBM 2021.
+#
+# 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.
+
+"""Utility functions related to storing account configuration on disk."""
+
+import json
+import os
+from typing import Optional, Union
+
+
+def save_config(
+    filename: str,
+    name: str,
+    config: dict,
+) -> None:
+    """Save configuration data in a JSON file under the given name."""
+
+    _ensure_file_exists(filename)
+
+    with open(filename, mode="r") as json_in:
+        data = json.load(json_in)
+
+    with open(filename, mode="w") as json_out:
+        data[name] = config
+        json.dump(data, json_out, sort_keys=True, indent=4)
+
+
+def read_config(
+    filename: str,
+    name: Optional[str] = None,
+) -> Union[dict, None]:
+    """Save configuration data from a JSON file."""
+
+    _ensure_file_exists(filename)
+
+    with open(filename) as json_file:
+        data = json.load(json_file)
+        if name is None:
+            return data
+        if name in data:
+            return data[name]
+
+        return None
+
+
+def delete_config(
+    filename: str,
+    name: str,
+) -> bool:
+    """Delete configuration data from a JSON file."""
+
+    _ensure_file_exists(filename)
+    with open(filename, mode="r") as json_in:
+        data = json.load(json_in)
+
+    if name in data:
+        with open(filename, mode="w") as json_out:
+            del data[name]
+            json.dump(data, json_out, sort_keys=True, indent=4)
+            return True
+
+    return False
+
+
+def _ensure_file_exists(filename: str, initial_content: str = "{}") -> None:
+    if not os.path.isfile(filename):
+
+        # create parent directories
+        os.makedirs(os.path.dirname(filename), exist_ok=True)
+
+        # initialize file
+        with open(filename, mode="w") as json_file:
+            json_file.write(initial_content)

qiskit_ibm_runtime/credentials/__init__.py

@@ -32,47 +32,31 @@
 .. autosummary::
     :toctree: ../stubs/
 
-    CredentialsError
-    InvalidCredentialsFormatError
-    CredentialsNotFoundError
+
 """
 
-from collections import OrderedDict
-from typing import Dict, Optional, Tuple, Any
 import logging
+from collections import OrderedDict
+from typing import Dict, Tuple, Any
 
 from .credentials import Credentials
-from .hub_group_project_id import HubGroupProjectID
+from .environ import read_credentials_from_environ
 from .exceptions import (
     CredentialsError,
-    InvalidCredentialsFormatError,
-    CredentialsNotFoundError,
     HubGroupProjectIDInvalidStateError,
 )
-from .configrc import (
-    read_credentials_from_qiskitrc,
-    store_credentials,
-    store_preferences,
-)
-from .environ import read_credentials_from_environ
+from .hub_group_project_id import HubGroupProjectID
 
 logger = logging.getLogger(__name__)
 
 
-def discover_credentials(
-    qiskitrc_filename: Optional[str] = None,
-) -> Tuple[Dict[HubGroupProjectID, Credentials], Dict]:
+def discover_credentials() -> Tuple[Dict[HubGroupProjectID, Credentials], Dict]:
     """Automatically discover credentials for IBM Quantum.
 
     This method looks for credentials in the following places in order and
     returns the first ones found:
 
         1. The environment variables.
-        2. The ``qiskitrc`` configuration file
-
-    Args:
-        qiskitrc_filename: Full path to the ``qiskitrc`` configuration
-            file. If ``None``, ``$HOME/.qiskitrc/qiskitrc`` is used.
 
     Raises:
         HubGroupProjectIDInvalidStateError: If the default provider stored on
@@ -92,10 +76,6 @@ def discover_credentials(
     readers = OrderedDict(
         [
             ("environment variables", (read_credentials_from_environ, {})),
-            (
-                "qiskitrc",
-                (read_credentials_from_qiskitrc, {"filename": qiskitrc_filename}),
-            ),
         ]
     )  # type: OrderedDict[str, Any]