chore!: require Python >=3.10; remove deprecated NWIS_Metadata.variable_info

Ahead of the breaking 1.2.0 release.

Require Python >=3.10
- 3.9 support was already effectively broken: `waterdata`'s `anyio` dependency
  and the test stack (`pytest-httpx`) require 3.10+, and the `waterdata` test
  modules already skip on <3.10 — so the CI 3.9 leg was a hollow shell.
- `requires-python = ">=3.10"`; ruff `target-version = "py310"`; mypy
  `python_version = "3.10"`. Bumping mypy to 3.10 also lets it parse `anyio`'s
  3.10 source (the `mypy<2` pin existed only to keep targeting 3.9, now dropped).
- Declare `anyio>=4.0` as a direct dependency — it's imported directly by
  `waterdata` (`start_blocking_portal`), previously relied on transitively via
  httpx.
- CI test matrix `["3.9", "3.13", "3.14"]` -> `["3.10", "3.13", "3.14"]`.
- Fill in the Trove classifiers (per-version 3.10-3.14, dev-status, audience,
  topic).
- The py310 ruff target enables `B905`; add explicit `strict=False` to the four
  pre-existing `zip()` calls (`nwis`, `waterdata/chunking`, `waterdata/nearest`)
  — identical to the prior implicit behavior.

Remove deprecated `NWIS_Metadata.variable_info`
- It only emitted a `DeprecationWarning` and returned `None` (it relied on the
  defunct `get_pmcodes`). Accessing it now raises `NotImplementedError` via the
  `utils.BaseMetadata` abstract contract. Drops the obsolete unit test.

BREAKING CHANGE: Python 3.9 is no longer supported; `pip install
dataretrieval>=1.2.0` requires Python >=3.10. `NWIS_Metadata.variable_info` is
removed (it always returned None).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Sjb14HkwuCydKSKMsaXsgd

Author: thodson-usgs

.github/workflows/python-package.yml

@@ -49,7 +49,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [ubuntu-latest, windows-latest]
-        python-version: ["3.9", "3.13", "3.14"]
+        python-version: ["3.10", "3.13", "3.14"]
 
     steps:
       - uses: actions/checkout@v6

NEWS.md

@@ -1,3 +1,5 @@
+**06/23/2026:** **Breaking change (1.2.0):** the minimum supported Python is now **3.10** (`requires-python = ">=3.10"`). 3.9 support was already effectively broken — the `waterdata` module's dependencies (`anyio`, the test stack) require 3.10+, and the `waterdata` test modules already skipped on <3.10. `anyio` is now declared as a direct dependency (it is imported directly by `waterdata`), and the CI/ruff/mypy targets move to 3.10. Also removed the deprecated `NWIS_Metadata.variable_info` property (it only warned and returned `None`, relying on the defunct `get_pmcodes`); accessing it now raises `NotImplementedError` via the base class.
+
 **06/03/2026:** The request-error hierarchy is now unified. Every module (`nwis`, `wqp`, `nldi`, `waterdata`, `nadp`, `streamstats`) raises a subclass of `dataretrieval.DataRetrievalError` on a failed request, so a single `except dataretrieval.DataRetrievalError` spans them all. An HTTP error status surfaces as an `HTTPError` carrying `.status_code` (inspect it to branch on a specific code); the retryable 429/5xx subset is `TransientError` (`RateLimited` / `ServiceUnavailable`, carrying `.retry_after`); and a request too large to satisfy is a `RequestTooLarge` (`URLTooLong` for an over-long single request, `Unchunkable` when the Water Data chunker cannot split a call small enough). Connection-level failures (timeouts, DNS, refused connections) are wrapped as a `NetworkError`, with the underlying `httpx` exception on `__cause__`. Every `DataRetrievalError` also exposes `.status_code` (`None` when there is no HTTP status), `.retry_after`, and `.retryable`, so a single `except dataretrieval.DataRetrievalError as e` clause can branch on the status or retry transient failures without knowing the concrete subclass. **Breaking change:** these exceptions no longer multiply-inherit a built-in — code that caught request failures with `except ValueError` or `except RuntimeError` should switch to `except dataretrieval.DataRetrievalError` (or a specific subclass). A no-data result is **not** an error: the modern getters (`waterdata`, `wqp`, `nldi`) return an empty DataFrame when nothing matches. Only the deprecated `nwis` (waterservices) path still raises `NoSitesError` on no data.
 
 **05/17/2026:** The OGC `waterdata` getters (`get_daily`, `get_continuous`, `get_field_measurements`, and the rest of the multi-value-capable functions) now transparently chunk requests whose URLs would otherwise exceed the server's ~8 KB byte limit.

dataretrieval/nwis.py

@@ -1033,11 +1033,15 @@ def _read_json(json: dict[str, Any]) -> pd.DataFrame:
     # for example, [0, 21, 22] would be the first and last indices
     index_list = [0]
     index_list.extend(
-        [i + 1 for i, (a, b) in enumerate(zip(site_list[:-1], site_list[1:])) if a != b]
+        [
+            i + 1
+            for i, (a, b) in enumerate(zip(site_list[:-1], site_list[1:], strict=False))
+            if a != b
+        ]
     )
     index_list.append(len(site_list))
 
-    for start, end in zip(index_list[:-1], index_list[1:]):
+    for start, end in zip(index_list[:-1], index_list[1:], strict=False):
         # grab a block containing timeseries 0:21,
         # which are all from the same site
         site_block = json["value"]["timeSeries"][start:end]
@@ -1133,8 +1137,8 @@ class NWIS_Metadata(BaseMetadata):
 
     Notes
     -----
-    ``site_info`` and ``variable_info`` are exposed as properties (documented
-    below) rather than plain attributes.
+    ``site_info`` is exposed as a property (documented below) rather than a
+    plain attribute.
 
     """
 
@@ -1196,17 +1200,3 @@ def site_info(self) -> tuple[pd.DataFrame, BaseMetadata] | None:
 
         else:
             return None  # don't set metadata site_info attribute
-
-    @property
-    def variable_info(self) -> None:
-        """
-        Deprecated. Accessing variable_info via NWIS_Metadata is deprecated.
-        Returns None.
-        """
-        warnings.warn(
-            "Accessing variable_info via NWIS_Metadata is deprecated as "
-            "it relies on the defunct get_pmcodes function.",
-            DeprecationWarning,
-            stacklevel=2,
-        )
-        return None

dataretrieval/waterdata/chunking.py

@@ -976,7 +976,7 @@ def iter_sub_args(self) -> Iterator[dict[str, Any]]:
         chunk_lists = [self.chunks[ax.arg_key] for ax in self.axes]
         for combo in itertools.product(*chunk_lists):
             sub_args = dict(self.args)
-            for axis, chunk in zip(self.axes, combo):
+            for axis, chunk in zip(self.axes, combo, strict=False):
                 sub_args[axis.arg_key] = axis.render(chunk)
             yield sub_args
 

dataretrieval/waterdata/nearest.py

@@ -197,7 +197,8 @@ def _build_window_or_filter(targets: pd.DatetimeIndex, window_td: pd.Timedelta)
     lowers = (targets - window_td).strftime(fmt)
     uppers = (targets + window_td).strftime(fmt)
     return " OR ".join(
-        f"(time >= '{lo}' AND time <= '{up}')" for lo, up in zip(lowers, uppers)
+        f"(time >= '{lo}' AND time <= '{up}')"
+        for lo, up in zip(lowers, uppers, strict=False)
     )
 
 

pyproject.toml

@@ -6,7 +6,7 @@ build-backend = "setuptools.build_meta"
 name = "dataretrieval"
 description = "Discover and retrieve water data from U.S. federal hydrologic web services."
 readme = "README.md"
-requires-python = ">=3.9"
+requires-python = ">=3.10"
 keywords = ["USGS", "water data"]
 license = "CC0-1.0"
 license-files = ["LICENSE.md"]
@@ -17,11 +17,22 @@ maintainers = [
   {name = "Elise Hinman", email = "ehinman@usgs.gov"},
 ]
 classifiers = [
+    "Development Status :: 5 - Production/Stable",
+    "Intended Audience :: Science/Research",
+    "Topic :: Scientific/Engineering :: Hydrology",
     "Programming Language :: Python :: 3",
+    "Programming Language :: Python :: 3.10",
+    "Programming Language :: Python :: 3.11",
+    "Programming Language :: Python :: 3.12",
+    "Programming Language :: Python :: 3.13",
+    "Programming Language :: Python :: 3.14",
 ]
 dependencies = [
     "httpx",
     "pandas>=2.0.0,<4.0.0",
+    # Directly imported by ``waterdata`` (``anyio.from_thread.start_blocking_portal``),
+    # so declared here rather than relied on transitively via httpx.
+    "anyio>=4.0",
 ]
 dynamic = ["version"]
 
@@ -35,7 +46,7 @@ dataretrieval = ["py.typed"]
 # Minimal set the CI ``type-check`` job installs — just mypy + the package,
 # not the whole test stack.
 type-check = [
-  "mypy<2",  # <2 so it can still target Python 3.9 (the project's floor)
+  "mypy",
 ]
 test = [
   "pytest > 5.0.0",
@@ -77,7 +88,7 @@ repository = "https://github.com/DOI-USGS/dataretrieval-python.git"
 write_to = "dataretrieval/_version.py"
 
 [tool.ruff]
-target-version = "py39"
+target-version = "py310"
 extend-exclude = ["demos"]
 
 [tool.ruff.lint]
@@ -115,7 +126,7 @@ docstring-code-line-length = 72
 # libraries (pandas, geopandas, anyio) are treated as ``Any`` instead of
 # requiring stub packages. Dropping that — via pandas-stubs/types-requests and
 # per-module overrides — can follow.
-python_version = "3.9"  # the project's minimum supported version
+python_version = "3.10"  # the project's minimum supported version
 files = ["dataretrieval"]
 strict = true
 ignore_missing_imports = true

tests/nwis_test.py

@@ -405,17 +405,6 @@ def test_set_metadata_info_countyCd(self):
         # assert that site_info is implemented
         assert md.site_info
 
-    def test_variable_info_deprecated(self):
-        """Test that variable_info raises a DeprecationWarning and returns None."""
-        response = mock.MagicMock()
-        md = NWIS_Metadata(response)
-        with pytest.warns(
-            DeprecationWarning,
-            match="Accessing variable_info via NWIS_Metadata is deprecated",
-        ):
-            result = md.variable_info
-        assert result is None
-
 
 class TestReadRdb:
     """Tests for the NWIS-specific _read_rdb wrapper.