From aadceb033dde7bb66d4ac74ad3cc1f29c4f8d962 Mon Sep 17 00:00:00 2001
From: kevin-tian <kevin.tian@ibm.com>
Date: Wed, 10 Jan 2024 13:36:20 -0500
Subject: [PATCH 1/8] Update from_id()

---
 qiskit_ibm_runtime/session.py | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/qiskit_ibm_runtime/session.py b/qiskit_ibm_runtime/session.py
index 5647f5a44..96ac4047b 100644
--- a/qiskit_ibm_runtime/session.py
+++ b/qiskit_ibm_runtime/session.py
@@ -20,6 +20,7 @@
 from qiskit_ibm_provider.utils.converters import hms_to_seconds
 
 from qiskit_ibm_runtime import QiskitRuntimeService
+from .exceptions import IBMInputValueError
 from .runtime_job import RuntimeJob
 from .utils.result_decoder import ResultDecoder
 from .ibm_backend import IBMBackend
@@ -304,12 +305,33 @@ def from_id(
             backend: instance of :class:`qiskit_ibm_runtime.IBMBackend` class or
                 string name of backend.
 
+         Raises:
+            IBMInputValueError: If given `session_id` does not exist. or the backend passed in does
+                not match the original session backend.
+
         Returns:
             A new Session with the given ``session_id``
 
         """
         if backend:
             deprecate_arguments("backend", "0.15.0", "Sessions do not support multiple backends.")
+            if isinstance(backend, IBMBackend):
+                backend = backend.name
+
+        if service:
+            response = service._api_client.session_details(session_id)
+            if response:
+                session_backend = response.get("backend_name")
+                if backend and backend != session_backend:
+                    raise IBMInputValueError(
+                        f"The session_id {session_id} was created with backend {session_backend}, "
+                        f"but backend {backend} was given."
+                    )
+                backend = session_backend
+            else:
+                raise IBMInputValueError(f"The session_id {session_id} does not exist.")
+        if not service and not backend:
+            raise IBMInputValueError("Either service or backend must be given.")
 
         session = cls(service, backend)
         session._session_id = session_id

From 82aebd5fa9cdf269af607e9f147190cdc92b9bf4 Mon Sep 17 00:00:00 2001
From: kevin-tian <kevin.tian@ibm.com>
Date: Mon, 22 Jan 2024 00:41:03 -0500
Subject: [PATCH 2/8] update docstring

---
 qiskit_ibm_runtime/session.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/qiskit_ibm_runtime/session.py b/qiskit_ibm_runtime/session.py
index 96ac4047b..cd64dc88c 100644
--- a/qiskit_ibm_runtime/session.py
+++ b/qiskit_ibm_runtime/session.py
@@ -302,8 +302,8 @@ def from_id(
             session_id: the id of the session to be created. This must be an already
                 existing session id.
             service: instance of the ``QiskitRuntimeService`` class.
-            backend: instance of :class:`qiskit_ibm_runtime.IBMBackend` class or
-                string name of backend.
+            backend (DEPRECATED): instance of :class:`qiskit_ibm_runtime.IBMBackend` class or
+                string name of backend. Either ``service`` or ``backend`` must be given.
 
          Raises:
             IBMInputValueError: If given `session_id` does not exist. or the backend passed in does

From 101363dd52e8b3711a3e400a8be45ef39c9bfd06 Mon Sep 17 00:00:00 2001
From: kevin-tian <kevin.tian@ibm.com>
Date: Tue, 27 Feb 2024 14:01:02 -0500
Subject: [PATCH 3/8] add service warning deprecation

---
 qiskit_ibm_runtime/session.py | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/qiskit_ibm_runtime/session.py b/qiskit_ibm_runtime/session.py
index dc5cb91ba..3a7cada68 100644
--- a/qiskit_ibm_runtime/session.py
+++ b/qiskit_ibm_runtime/session.py
@@ -12,6 +12,7 @@
 
 """Qiskit Runtime flexible session."""
 
+import warnings
 from typing import Dict, Optional, Type, Union, Callable, Any
 from types import TracebackType
 from functools import wraps
@@ -321,7 +322,9 @@ def from_id(
 
         """
         if backend:
-            deprecate_arguments("backend", "0.15.0", "Sessions do not support multiple backends.")
+            deprecate_arguments(
+                "backend", "0.15.0", "The backend used to open the session will be used."
+            )
             if isinstance(backend, IBMBackend):
                 backend = backend.name
 
@@ -337,6 +340,15 @@ def from_id(
                 backend = session_backend
             else:
                 raise IBMInputValueError(f"The session_id {session_id} does not exist.")
+        else:
+            warnings.warn(
+                (
+                    "The `service` parameter will be required in a future release no sooner than "
+                    "3 months after the release of qiskit-ibm-runtime 0.21.0 ."
+                ),
+                DeprecationWarning,
+                stacklevel=2,
+            )
         if not service and not backend:
             raise IBMInputValueError("Either service or backend must be given.")
 

From 14d240ea3b148f41bd00d8dee987758025519aa4 Mon Sep 17 00:00:00 2001
From: kevin-tian <kevin.tian@ibm.com>
Date: Fri, 1 Mar 2024 21:23:06 -0500
Subject: [PATCH 4/8] add mode to session details

---
 qiskit_ibm_runtime/session.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/qiskit_ibm_runtime/session.py b/qiskit_ibm_runtime/session.py
index d0cbf386a..1a02787d1 100644
--- a/qiskit_ibm_runtime/session.py
+++ b/qiskit_ibm_runtime/session.py
@@ -265,6 +265,7 @@ def details(self) -> Optional[Dict[str, Any]]:
             started_at: Timestamp of when the session was started.
             closed_at: Timestamp of when the session was closed.
             activated_at: Timestamp of when the session state was changed to active.
+            mode: Execution mode of the session
         """
         if self._session_id:
             response = self._service._api_client.session_details(self._session_id)
@@ -282,6 +283,7 @@ def details(self) -> Optional[Dict[str, Any]]:
                     "started_at": response.get("started_at"),
                     "closed_at": response.get("closed_at"),
                     "activated_at": response.get("activated_at"),
+                    "mode": response.get("mode"),
                 }
         return None
 

From 97553ed4817a30afbb65d97efbe1b3cd0ca5ba29 Mon Sep 17 00:00:00 2001
From: kevin-tian <kevin.tian@ibm.com>
Date: Fri, 5 Apr 2024 16:13:41 -0400
Subject: [PATCH 5/8] address comments

---
 .../api/rest/runtime_session.py               |  6 +--
 qiskit_ibm_runtime/session.py                 | 39 ++++++-------------
 test/integration/test_session.py              |  2 +-
 3 files changed, 14 insertions(+), 33 deletions(-)

diff --git a/qiskit_ibm_runtime/api/rest/runtime_session.py b/qiskit_ibm_runtime/api/rest/runtime_session.py
index 87f66c076..7a585b54e 100644
--- a/qiskit_ibm_runtime/api/rest/runtime_session.py
+++ b/qiskit_ibm_runtime/api/rest/runtime_session.py
@@ -83,8 +83,4 @@ def close(self) -> None:
 
     def details(self) -> Dict[str, Any]:
         """Return the details of this session."""
-        try:
-            return self.session.get(self.get_url("self")).json()
-        # return None if API is not supported
-        except:  # pylint: disable=bare-except
-            return None
+        return self.session.get(self.get_url("self")).json()
diff --git a/qiskit_ibm_runtime/session.py b/qiskit_ibm_runtime/session.py
index 6fbe4f9d1..14f45b8f8 100644
--- a/qiskit_ibm_runtime/session.py
+++ b/qiskit_ibm_runtime/session.py
@@ -28,7 +28,7 @@
 from .utils.result_decoder import ResultDecoder
 from .ibm_backend import IBMBackend
 from .utils.default_session import set_cm_session
-from .utils.deprecation import deprecate_arguments, issue_deprecation_msg
+from .utils.deprecation import issue_deprecation_msg
 from .utils.converters import hms_to_seconds
 from .fake_provider.local_service import QiskitRuntimeLocalService
 
@@ -332,7 +332,6 @@ def from_id(
         cls,
         session_id: str,
         service: Optional[QiskitRuntimeService] = None,
-        backend: Optional[Union[str, IBMBackend]] = None,
     ) -> "Session":
         """Construct a Session object with a given session_id
 
@@ -340,8 +339,6 @@ def from_id(
             session_id: the id of the session to be created. This must be an already
                 existing session id.
             service: instance of the ``QiskitRuntimeService`` class.
-            backend (DEPRECATED): instance of :class:`qiskit_ibm_runtime.IBMBackend` class or
-                string name of backend. Either ``service`` or ``backend`` must be given.
 
          Raises:
             IBMInputValueError: If given `session_id` does not exist. or the backend passed in does
@@ -351,36 +348,24 @@ def from_id(
             A new Session with the given ``session_id``
 
         """
-        if backend:
-            deprecate_arguments(
-                "backend", "0.15.0", "The backend used to open the session will be used."
-            )
-            if isinstance(backend, IBMBackend):
-                backend = backend.name
-
-        if service:
-            response = service._api_client.session_details(session_id)
-            if response:
-                session_backend = response.get("backend_name")
-                if backend and backend != session_backend:
-                    raise IBMInputValueError(
-                        f"The session_id {session_id} was created with backend {session_backend}, "
-                        f"but backend {backend} was given."
-                    )
-                backend = session_backend
-            else:
-                raise IBMInputValueError(f"The session_id {session_id} does not exist.")
-        else:
+        if not service:
             warnings.warn(
                 (
                     "The `service` parameter will be required in a future release no sooner than "
-                    "3 months after the release of qiskit-ibm-runtime 0.21.0 ."
+                    "3 months after the release of qiskit-ibm-runtime 0.23.0 ."
                 ),
                 DeprecationWarning,
                 stacklevel=2,
             )
-        if not service and not backend:
-            raise IBMInputValueError("Either service or backend must be given.")
+            service = QiskitRuntimeService()
+
+        response = service._api_client.session_details(session_id)
+        backend = response.get("backend_name")
+        mode = response.get("mode")
+        if mode != cls.__name__.lower():
+            raise IBMInputValueError(
+                f"Session ID {session_id} has session mode {mode} instead of {cls.__name__}."
+            )
 
         session = cls(service, backend)
         session._session_id = session_id
diff --git a/test/integration/test_session.py b/test/integration/test_session.py
index 03cd309f0..44f0e8326 100644
--- a/test/integration/test_session.py
+++ b/test/integration/test_session.py
@@ -100,7 +100,7 @@ def test_session_from_id(self, service):
             sampler = Sampler(session=session)
             job = sampler.run(bell(), shots=400)
             session_id = job.session_id
-        new_session = Session.from_id(backend=backend, session_id=session_id)
+        new_session = Session.from_id(session_id=session_id, service=service)
         sampler = Sampler(session=new_session)
         job = sampler.run(bell(), shots=400)
         self.assertEqual(session_id, job.session_id)

From d607ac5d213e554d059f70e31dafd4f17704154e Mon Sep 17 00:00:00 2001
From: kevin-tian <kevin.tian@ibm.com>
Date: Mon, 8 Apr 2024 13:54:46 -0400
Subject: [PATCH 6/8] Update tests

---
 qiskit_ibm_runtime/session.py         |  3 ++-
 test/integration/test_session.py      | 24 ++++++++++++++++--------
 test/unit/mock/fake_runtime_client.py |  4 ++++
 test/unit/test_session.py             |  2 +-
 4 files changed, 23 insertions(+), 10 deletions(-)

diff --git a/qiskit_ibm_runtime/session.py b/qiskit_ibm_runtime/session.py
index b9c05b90a..650b9a778 100644
--- a/qiskit_ibm_runtime/session.py
+++ b/qiskit_ibm_runtime/session.py
@@ -365,7 +365,8 @@ def from_id(
         response = service._api_client.session_details(session_id)
         backend = response.get("backend_name")
         mode = response.get("mode")
-        if mode != cls.__name__.lower():
+        class_name = "dedicated" if cls.__name__.lower() == "session" else cls.__name__.lower()
+        if mode != class_name:
             raise IBMInputValueError(
                 f"Session ID {session_id} has session mode {mode} instead of {cls.__name__}."
             )
diff --git a/test/integration/test_session.py b/test/integration/test_session.py
index 44f0e8326..b911eca03 100644
--- a/test/integration/test_session.py
+++ b/test/integration/test_session.py
@@ -13,6 +13,7 @@
 """Integration tests for Session."""
 
 import warnings
+from unittest import SkipTest
 
 from qiskit.circuit.library import RealAmplitudes
 from qiskit.quantum_info import SparsePauliOp
@@ -21,7 +22,8 @@
 from qiskit.result import Result
 from qiskit.transpiler.preset_passmanagers import generate_preset_pass_manager
 
-from qiskit_ibm_runtime import Estimator, Session, Sampler, Options
+from qiskit_ibm_runtime import Estimator, Session, Sampler, Options, Batch
+from qiskit_ibm_runtime.exceptions import IBMInputValueError
 
 from ..utils import bell
 from ..decorators import run_integration_test, quantum_only
@@ -95,15 +97,21 @@ def test_using_correct_instance(self, service):
     @run_integration_test
     def test_session_from_id(self, service):
         """Test creating a session from a given id"""
-        backend = service.backend("ibmq_qasm_simulator")
+        try:
+            backend = service.backend("fake_backend1")
+        except:
+            raise SkipTest("No proper backends available")
+        pm = generate_preset_pass_manager(backend=backend, optimization_level=1)
+        isa_circuit = pm.run(bell())
         with Session(service, backend=backend) as session:
             sampler = Sampler(session=session)
-            job = sampler.run(bell(), shots=400)
-            session_id = job.session_id
-        new_session = Session.from_id(session_id=session_id, service=service)
-        sampler = Sampler(session=new_session)
-        job = sampler.run(bell(), shots=400)
-        self.assertEqual(session_id, job.session_id)
+            sampler.run(isa_circuit)
+
+        new_session = Session.from_id(session_id=session._session_id, service=service)
+        self.assertEqual(session._session_id, new_session._session_id)
+
+        with self.assertRaises(IBMInputValueError):
+            Batch.from_id(session_id=session._session_id, service=service)
 
 
 class TestBackendRunInSession(IBMIntegrationTestCase):
diff --git a/test/unit/mock/fake_runtime_client.py b/test/unit/mock/fake_runtime_client.py
index a977597a7..362b096d7 100644
--- a/test/unit/mock/fake_runtime_client.py
+++ b/test/unit/mock/fake_runtime_client.py
@@ -478,6 +478,10 @@ def close_session(self, session_id: str) -> None:
             raise ValueError(f"Session {session_id} not found.")
         self._sessions.remove(session_id)
 
+    def session_details(self, session_id: str) -> dict[str, Any]:
+        """Return the details of the session."""
+        return {"id": session_id, "mode": "session"}
+
     def _find_backend(self, backend_name):
         for back in self._backends:
             if back.name == backend_name:
diff --git a/test/unit/test_session.py b/test/unit/test_session.py
index b0ae0211d..63d461d87 100644
--- a/test/unit/test_session.py
+++ b/test/unit/test_session.py
@@ -161,7 +161,7 @@ def test_global_service(self):
 
     def test_session_from_id(self):
         """Create session with given session_id"""
-        service = MagicMock()
+        service = FakeRuntimeService()
         session_id = "123"
         session = Session.from_id(session_id=session_id, service=service)
         session.run(program_id="foo", inputs={})

From 992f26c31a3e79ef24f53516f56bf3207e35517f Mon Sep 17 00:00:00 2001
From: kevin-tian <kevin.tian@ibm.com>
Date: Mon, 8 Apr 2024 14:06:48 -0400
Subject: [PATCH 7/8] Address docstring comments

---
 qiskit_ibm_runtime/session.py         | 6 +++---
 test/unit/mock/fake_runtime_client.py | 2 +-
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/qiskit_ibm_runtime/session.py b/qiskit_ibm_runtime/session.py
index 650b9a778..17c3d0649 100644
--- a/qiskit_ibm_runtime/session.py
+++ b/qiskit_ibm_runtime/session.py
@@ -342,10 +342,10 @@ def from_id(
             session_id: the id of the session to be created. This must be an already
                 existing session id.
             service: instance of the ``QiskitRuntimeService`` class.
+                If ``None``, ``QiskitRuntimeService()`` is used to initialize your default saved account.
 
          Raises:
-            IBMInputValueError: If given `session_id` does not exist. or the backend passed in does
-                not match the original session backend.
+            IBMInputValueError: If given `session_id` does not exist.
 
         Returns:
             A new Session with the given ``session_id``
@@ -368,7 +368,7 @@ def from_id(
         class_name = "dedicated" if cls.__name__.lower() == "session" else cls.__name__.lower()
         if mode != class_name:
             raise IBMInputValueError(
-                f"Session ID {session_id} has session mode {mode} instead of {cls.__name__}."
+                f"Input ID {session_id} has execution mode {mode} instead of {class_name}."
             )
 
         session = cls(service, backend)
diff --git a/test/unit/mock/fake_runtime_client.py b/test/unit/mock/fake_runtime_client.py
index 362b096d7..e0704fb9c 100644
--- a/test/unit/mock/fake_runtime_client.py
+++ b/test/unit/mock/fake_runtime_client.py
@@ -478,7 +478,7 @@ def close_session(self, session_id: str) -> None:
             raise ValueError(f"Session {session_id} not found.")
         self._sessions.remove(session_id)
 
-    def session_details(self, session_id: str) -> dict[str, Any]:
+    def session_details(self, session_id: str) -> Dict[str, Any]:
         """Return the details of the session."""
         return {"id": session_id, "mode": "session"}
 

From b4eafa220ab2f558c5a8ffd891ae11b82bc7aa99 Mon Sep 17 00:00:00 2001
From: kevin-tian <kevin.tian@ibm.com>
Date: Mon, 8 Apr 2024 18:18:43 -0400
Subject: [PATCH 8/8] update unit test

---
 test/unit/mock/fake_runtime_client.py | 2 +-
 test/unit/test_session.py             | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/unit/mock/fake_runtime_client.py b/test/unit/mock/fake_runtime_client.py
index e0704fb9c..9dcd2a089 100644
--- a/test/unit/mock/fake_runtime_client.py
+++ b/test/unit/mock/fake_runtime_client.py
@@ -480,7 +480,7 @@ def close_session(self, session_id: str) -> None:
 
     def session_details(self, session_id: str) -> Dict[str, Any]:
         """Return the details of the session."""
-        return {"id": session_id, "mode": "session"}
+        return {"id": session_id, "mode": "dedicated", "backend_name": "common_backend"}
 
     def _find_backend(self, backend_name):
         for back in self._backends:
diff --git a/test/unit/test_session.py b/test/unit/test_session.py
index 63d461d87..930ec89a6 100644
--- a/test/unit/test_session.py
+++ b/test/unit/test_session.py
@@ -161,7 +161,7 @@ def test_global_service(self):
 
     def test_session_from_id(self):
         """Create session with given session_id"""
-        service = FakeRuntimeService()
+        service = FakeRuntimeService(channel="ibm_quantum", token="abc")
         session_id = "123"
         session = Session.from_id(session_id=session_id, service=service)
         session.run(program_id="foo", inputs={})