deps: Drop support for Python 3.7 and 3.8

.github/sync-repo-settings.yaml

@@ -11,7 +11,6 @@ branchProtectionRules:
     - 'cla/google'
     - 'docs'
     - 'lint'
-    - 'unit (3.8)'
     - 'unit (3.9)'
     - 'unit (3.10)'
     - 'unit (3.11)'

.github/workflows/lint.yml

@@ -12,7 +12,7 @@ jobs:
     - name: Setup Python
       uses: actions/setup-python@v5
       with:
-        python-version: "3.8"
+        python-version: "3.9"
     - name: Install nox
       run: |
         python -m pip install --upgrade setuptools pip wheel

.github/workflows/unittest.yml

@@ -5,37 +5,35 @@
 name: unittest
 jobs:
   unit:
-    # TODO(https://github.com/googleapis/gapic-generator-python/issues/2303): use `ubuntu-latest` once this bug is fixed.
-    # Use ubuntu-22.04 until Python 3.7 is removed from the test matrix
-    # https://docs.github.com/en/actions/using-github-hosted-runners/using-github-hosted-runners/about-github-hosted-runners#standard-github-hosted-runners-for-public-repositories
-    runs-on: ubuntu-22.04
+    # Use `ubuntu-latest` runner.
+    runs-on: ubuntu-latest
     strategy:
       matrix:
-        python: ['3.8', '3.9', '3.10', '3.11', '3.12', '3.13']
+        python: ['3.9', '3.10', '3.11', '3.12', '3.13']
     steps:
     - name: Checkout
       uses: actions/checkout@v4
     - name: Setup Python
       uses: actions/setup-python@v5
       with:
         python-version: ${{ matrix.python }}
     - name: Install nox
       run: |
         python -m pip install --upgrade setuptools pip wheel
         python -m pip install nox
     - name: Run unit tests
       env:
         COVERAGE_FILE: .coverage-${{ matrix.python }}
       run: |
         nox -s unit-${{ matrix.python }}
     - name: Upload coverage results
       uses: actions/upload-artifact@v4
       with:
         name: coverage-artifact-${{ matrix.python }}
         path: .coverage-${{ matrix.python }}
         include-hidden-files: true
 
   unit-prerelease:
     runs-on: ubuntu-latest
     strategy:
       matrix:
@@ -103,7 +101,7 @@
     - name: Setup Python
       uses: actions/setup-python@v5
       with:
-        python-version: "3.8"
+        python-version: "3.9"
     - name: Install coverage
       run: |
         python -m pip install --upgrade setuptools pip wheel

.kokoro/test-samples-impl.sh

@@ -33,8 +33,7 @@ export PYTHONUNBUFFERED=1
 env | grep KOKORO
 
 # Install nox
-# `virtualenv==20.26.6` is added for Python 3.7 compatibility
-python3.9 -m pip install --upgrade --quiet nox virtualenv==20.26.6
+python3.9 -m pip install --upgrade --quiet nox virtualenv
 
 # Use secrets acessor service account to get secrets
 if [[ -f "${KOKORO_GFILE_DIR}/secrets_viewer_service_account.json" ]]; then

CONTRIBUTING.rst

@@ -22,7 +22,7 @@ In order to add a feature:
   documentation.
 
 - The feature must work fully on the following CPython versions:
-  3.7, 3.8, 3.9, 3.10, 3.11, 3.12 and 3.13 on both UNIX and Windows.
+  3.9, 3.10, 3.11, 3.12 and 3.13 on both UNIX and Windows.
 
 - The feature must not add unnecessary dependencies (where
   "unnecessary" is of course subjective, but new dependencies should
@@ -143,12 +143,12 @@ Running System Tests
    $ nox -s system
 
    # Run a single system test
-   $ nox -s system-3.8 -- -k <name of test>
+   $ nox -s system-3.9 -- -k <name of test>
 
 
   .. note::
 
-      System tests are only configured to run under Python 3.8.
+      System tests are only configured to run under Python 3.9.
       For expediency, we do not run them in older versions of Python 3.
 
   This alone will not run the tests. You'll need to change some local
@@ -195,11 +195,11 @@ configure them just like the System Tests.
 
    # Run all tests in a folder
    $ cd samples/snippets
-   $ nox -s py-3.8
+   $ nox -s py-3.9
 
    # Run a single sample test
    $ cd samples/snippets
-   $ nox -s py-3.8 -- -k <name of test>
+   $ nox -s py-3.9 -- -k <name of test>
 
 ********************************************
 Note About ``README`` as it pertains to PyPI
@@ -221,16 +221,12 @@ Supported Python Versions
 
 We support:
 
--  `Python 3.7`_
--  `Python 3.8`_
 -  `Python 3.9`_
 -  `Python 3.10`_
 -  `Python 3.11`_
 -  `Python 3.12`_
 -  `Python 3.13`_
 
-.. _Python 3.7: https://docs.python.org/3.7/
-.. _Python 3.8: https://docs.python.org/3.8/
 .. _Python 3.9: https://docs.python.org/3.9/
 .. _Python 3.10: https://docs.python.org/3.10/
 .. _Python 3.11: https://docs.python.org/3.11/

README.rst

@@ -34,11 +34,11 @@ dependencies.
 
 Supported Python Versions
 ^^^^^^^^^^^^^^^^^^^^^^^^^
-Python >= 3.7
+Python >= 3.9
 
 Unsupported Python Versions
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^
-Python <= 3.6.
+Python <= 3.8.
 
 
 Mac/Linux

db_dtypes/__init__.py

@@ -21,15 +21,14 @@
 import warnings
 
 import numpy
-import packaging.version
 import pandas
 import pandas.api.extensions
 from pandas.errors import OutOfBoundsDatetime
 import pyarrow
 import pyarrow.compute
 
 from db_dtypes import core
-from db_dtypes.version import __version__
+from db_dtypes.json import JSONArray, JSONDtype, JSONArrowType  # noqa: F401
 
 from . import _versions_helpers
 
@@ -47,15 +46,6 @@
 _NP_BOX_DTYPE = "datetime64[us]"
 
 
-# To use JSONArray and JSONDtype, you'll need Pandas 1.5.0 or later. With the removal
-# of Python 3.7 compatibility, the minimum Pandas version will be updated to 1.5.0.
-if packaging.version.Version(pandas.__version__) >= packaging.version.Version("1.5.0"):
-    from db_dtypes.json import JSONArray, JSONArrowType, JSONDtype
-else:
-    JSONArray = None
-    JSONDtype = None
-
-
 @pandas.api.extensions.register_extension_dtype
 class TimeDtype(core.BaseDatetimeDtype):
     """
@@ -347,6 +337,22 @@ def __sub__(self, other):
         return super().__sub__(other)
 
 
+def _determine_all(json_array_type, json_dtype_type):
+    """Determines the list for __all__ based on JSON type availability."""
+    base_all = [
+        "__version__",
+        "DateArray",
+        "DateDtype",
+        "TimeArray",
+        "TimeDtype",
+    ]
+    # Check if both JSON types are available (truthy)
+    if json_array_type and json_dtype_type:
+        return base_all + ["JSONDtype", "JSONArray", "JSONArrowType"]
+    else:
+        return base_all
+
+
 def _check_python_version():
     """Checks the runtime Python version and issues a warning if needed."""
     sys_major, sys_minor, sys_micro = _versions_helpers.extract_runtime_version()
@@ -364,23 +370,4 @@ def _check_python_version():
 
 _check_python_version()
 
-
-if not JSONArray or not JSONDtype:
-    __all__ = [
-        "__version__",
-        "DateArray",
-        "DateDtype",
-        "TimeArray",
-        "TimeDtype",
-    ]
-else:
-    __all__ = [
-        "__version__",
-        "DateArray",
-        "DateDtype",
-        "JSONDtype",
-        "JSONArray",
-        "JSONArrowType",
-        "TimeArray",
-        "TimeDtype",
-    ]
+__all__ = _determine_all(JSONArray, JSONDtype)

db_dtypes/core.py

@@ -186,9 +186,6 @@ def median(
         keepdims: bool = False,
         skipna: bool = True,
     ):
-        if not hasattr(pandas_backports, "numpy_validate_median"):
-            raise NotImplementedError("Need pandas 1.3 or later to calculate median.")
-
         pandas_backports.numpy_validate_median(
             (),
             {"out": out, "overwrite_input": overwrite_input, "keepdims": keepdims},

db_dtypes/json.py

@@ -277,5 +277,10 @@ def to_pandas_dtype(self):
 
 
 # Register the type to be included in RecordBatches, sent over IPC and received in
-# another Python process.
-pa.register_extension_type(JSONArrowType())
+# another Python process. Also handle potential pre-registration
+try:
+    pa.register_extension_type(JSONArrowType())
+except pa.ArrowKeyError:
+    # Type 'dbjson' might already be registered if the module is reloaded,
+    # which is okay.
+    pass