Consolidate packaging functions into framework.package_deps

Queries and tests of installed package versions were spread across a few
different modules. Here they are combined into one module
(`package_deps.py`) as suggested in
qiskit-community#1427.

qiskit_experiments/data_processing/sklearn_discriminators.py

@@ -15,7 +15,7 @@
 from typing import Any, List, Dict, TYPE_CHECKING
 
 from qiskit_experiments.data_processing.discriminator import BaseDiscriminator
-from qiskit_experiments.warnings import HAS_SKLEARN
+from qiskit_experiments.framework.package_deps import HAS_SKLEARN
 
 if TYPE_CHECKING:
     from sklearn.discriminant_analysis import (

qiskit_experiments/database_service/utils.py

@@ -12,7 +12,6 @@
 
 """Experiment utility functions."""
 
-import importlib.metadata
 import io
 import zipfile
 import logging
@@ -37,11 +36,6 @@
 LOG = logging.getLogger(__name__)
 
 
-def qiskit_version():
-    """Return the Qiskit version."""
-    return {p: importlib.metadata.distribution(p).version for p in ("qiskit", "qiskit-experiments")}
-
-
 def parse_timestamp(utc_dt: Union[datetime, str]) -> datetime:
     """Parse a UTC ``datetime`` object or string.
 

qiskit_experiments/framework/__init__.py

@@ -155,4 +155,3 @@
 )
 from .json import ExperimentEncoder, ExperimentDecoder
 from .restless_mixin import RestlessMixin
-from .package_deps import numpy_version

qiskit_experiments/framework/analysis_result.py

@@ -33,7 +33,7 @@
 
 from qiskit_experiments.database_service.device_component import DeviceComponent, to_component
 from qiskit_experiments.database_service.exceptions import ExperimentDataError
-from qiskit_experiments.database_service.utils import qiskit_version
+from qiskit_experiments.framework.package_deps import qiskit_version
 
 LOG = logging.getLogger(__name__)
 

qiskit_experiments/framework/experiment_data.py

@@ -47,7 +47,6 @@
 )
 from qiskit_experiments.framework.json import ExperimentEncoder, ExperimentDecoder
 from qiskit_experiments.database_service.utils import (
-    qiskit_version,
     plot_to_svg_bytes,
     ThreadSafeOrderedDict,
     ThreadSafeList,
@@ -59,6 +58,7 @@
 from qiskit_experiments.framework import BackendData
 from qiskit_experiments.framework.containers import ArtifactData
 from qiskit_experiments.framework import ExperimentStatus, AnalysisStatus, AnalysisCallback
+from qiskit_experiments.framework.package_deps import qiskit_version
 from qiskit_experiments.database_service.exceptions import (
     ExperimentDataError,
     ExperimentEntryNotFound,

qiskit_experiments/framework/package_deps.py

@@ -10,12 +10,62 @@
 # copyright notice, and modified files need to carry a notice indicating
 # that they have been altered from the originals.
 """
-Functions for checking dependency versions.
+Functions for checking and reporting installed package versions.
 """
 
-from importlib.metadata import version
+from __future__ import annotations
 
+from functools import lru_cache
+from importlib.metadata import version as metadata_version
 
-def numpy_version():
-    """Returns the current numpy version in (major, minor) form."""
-    return tuple(map(int, version("numpy").split(".")[:2]))
+from packaging.version import Version
+
+from qiskit.utils.lazy_tester import LazyImportTester
+
+
+__all__ = ["HAS_SKLEARN", "HAS_DYNAMICS", "qiskit_version", "version_is_at_least"]
+
+
+HAS_SKLEARN = LazyImportTester(
+    {
+        "sklearn.discriminant_analysis": (
+            "LinearDiscriminantAnalysis",
+            "QuadraticDiscriminantAnalysis",
+        )
+    },
+    name="scikit-learn",
+    install="pip install scikit-learn",
+)
+
+HAS_DYNAMICS = LazyImportTester(
+    "qiskit_dynamics",
+    name="qiskit-dynamics",
+    install="pip install qiskit-dynamics",
+)
+
+
+def qiskit_version() -> dict[str, str]:
+    """Return a deict with Qiskit names and versions."""
+    return {p: metadata_version(p) for p in ("qiskit", "qiskit-experiments")}
+
+
+@lru_cache(maxsize=None)
+def version_is_at_least(package: str, version: str) -> bool:
+    """Return True if the installed version of package greater than minimum version
+
+    Args:
+        package: Name of the package
+        version: Minimum version name as a string. This should just include
+            major, minor, and micro parts. The function will add ``.dev0`` to
+            also catch any pre-release versions (otherwise ``0.5.0a1`` would
+            evaluate as less than ``0.5.0``).
+
+    Returns:
+        True if installed version greater than ``version``. False if it is less.
+
+    Raises:
+        PackageNotFoundError:
+            If ``package`` is not installed.
+    """
+    installed_version = Version(metadata_version(package))
+    return installed_version > Version(f"{version}.dev0")

qiskit_experiments/library/characterization/analysis/multi_state_discrimination_analysis.py

@@ -21,7 +21,7 @@
 from qiskit_experiments.framework import BaseAnalysis, AnalysisResultData, ExperimentData
 from qiskit_experiments.data_processing import SkQDA
 from qiskit_experiments.visualization import BasePlotter, IQPlotter, MplDrawer, PlotStyle
-from qiskit_experiments.warnings import HAS_SKLEARN
+from qiskit_experiments.framework.package_deps import HAS_SKLEARN
 
 if TYPE_CHECKING:
     from sklearn.discriminant_analysis import QuadraticDiscriminantAnalysis

qiskit_experiments/library/tomography/tomography_analysis.py

@@ -25,7 +25,8 @@
 from qiskit.quantum_info.operators.channel.quantum_channel import QuantumChannel
 
 from qiskit_experiments.exceptions import AnalysisError
-from qiskit_experiments.framework import BaseAnalysis, AnalysisResultData, Options, numpy_version
+from qiskit_experiments.framework import BaseAnalysis, AnalysisResultData, Options
+from qiskit_experiments.framework.package_deps import version_is_at_least
 from .fitters import (
     tomography_fitter_data,
     postprocess_fitter,
@@ -311,7 +312,7 @@ def _fidelity_result(
         bs_fidelities = []
         for _ in range(self.options.target_bootstrap_samples):
             # TODO: remove conditional once numpy is pinned at 1.22 and above
-            if numpy_version() >= (1, 22):
+            if version_is_at_least("numpy", "1.22"):
                 sampled_data = rng.multinomial(shot_data, prob_data)
             else:
                 sampled_data = np.zeros_like(outcome_data)

qiskit_experiments/test/pulse_backend.py

@@ -13,13 +13,10 @@
 """A Pulse simulation backend based on Qiskit-Dynamics"""
 
 import datetime
-import importlib.metadata
-from functools import cached_property
 from itertools import chain
 from typing import Any, Dict, List, Optional, Tuple, Union
 
 import numpy as np
-from packaging.version import Version
 
 from qiskit import QuantumCircuit
 from qiskit.circuit import CircuitInstruction
@@ -38,9 +35,9 @@
 from qiskit.result import Result, Counts
 from qiskit.transpiler import InstructionProperties, Target
 
-from qiskit_experiments.warnings import HAS_DYNAMICS
 from qiskit_experiments.data_processing.discriminator import BaseDiscriminator
 from qiskit_experiments.exceptions import QiskitError
+from qiskit_experiments.framework.package_deps import HAS_DYNAMICS, version_is_at_least
 from qiskit_experiments.test.utils import FakeJob
 
 
@@ -513,7 +510,7 @@ def __init__(
         self.rabi_rate_12 = 6.876
 
         if noise is True:
-            if self._dynamics_ge_05:
+            if version_is_at_least("qiskit-dynamics", "0.5.0"):
                 solver_args = {
                     "array_library": "numpy",
                     "vectorized": True,
@@ -524,7 +521,7 @@ def __init__(
                 }
             static_dissipators = [t1_dissipator]
         else:
-            if self._dynamics_ge_05:
+            if version_is_at_least("qiskit-dynamics", "0.5.0"):
                 solver_args = {
                     "array_library": "numpy",
                 }
@@ -632,9 +629,3 @@ def __init__(
         self._simulated_pulse_unitaries = {
             (schedule.name, (0,), ()): self.solve(schedule, (0,)) for schedule in default_schedules
         }
-
-    @cached_property
-    def _dynamics_ge_05(self):
-        """True if installed version of qiskit-dynamics>=0.5.0.dev0"""
-        dyn_version = Version(importlib.metadata.distribution("qiskit-dynamics").version)
-        return dyn_version > Version("0.5.0.dev0")

test/data_processing/test_discriminator.py

@@ -20,7 +20,7 @@
 from qiskit.exceptions import MissingOptionalLibraryError
 
 from qiskit_experiments.data_processing import SkLDA, SkQDA
-from qiskit_experiments.warnings import HAS_SKLEARN
+from qiskit_experiments.framework.package_deps import HAS_SKLEARN
 
 
 def requires_sklearn(func):

test/library/characterization/test_multi_state_discrimination.py

@@ -23,7 +23,7 @@
 from qiskit_experiments.library import MultiStateDiscrimination
 from qiskit_experiments.test.pulse_backend import SingleTransmonTestBackend
 
-from qiskit_experiments.warnings import HAS_SKLEARN
+from qiskit_experiments.framework.package_deps import HAS_SKLEARN
 
 
 def requires_sklearn(func):

test/visualization/test_utils.py

@@ -22,7 +22,7 @@
 from qiskit.exceptions import QiskitError
 
 from qiskit_experiments.visualization.utils import DataExtentCalculator
-from qiskit_experiments.framework.package_deps import numpy_version
+from qiskit_experiments.framework.package_deps import version_is_at_least
 
 
 @ddt
@@ -49,7 +49,7 @@ def _dummy_data(
         # The result is a list of pairs representing a moving window of size 2.
         # TODO: remove the old code once numpy is above 1.20.
         dummy_data = []
-        if numpy_version() >= (1, 20):
+        if version_is_at_least("numpy", "1.20"):
             for (x_min, x_max), (y_min, y_max) in it.product(
                 *np.lib.stride_tricks.sliding_window_view(bin_edges, 2, 1)
             ):