ENH: Add tests for AWS access functionality

This requires some infrastructure to use VCRPy to record and mock out
web traffic, as well as an optional dependency on boto3.

Author: dopplershift

.gitattributes

@@ -6,4 +6,7 @@ staticdata/*.tbl text eol=lf
 *.ipynb	diff=jupyternotebook
 talks/* linguist-documentation
 src/metpy/io/_metar_parser/metar_parser.py linguist-generated=true
-src/metpy/_vendor/* linguist-vendored
+src/metpy/_vendor/* linguist-vendored
+
+# Mark the vcrpy cassettes as generated
+tests/remote/fixtures/* linguist-generated=true

.github/workflows/tests-pypi.yml

@@ -68,6 +68,9 @@ jobs:
             # Only needed while we support numpy 1.20
             if fname == 'requirements.txt':
               out.write('pillow!=10.4.0\n')
+            # Needed until minium vcrpy is >=7.0.0 for urllib3>=2.3
+            elif fname == 'requirements.txt':
+              out.write('urllib3==2.2.3\n')
         EOF
 
     - name: Install from PyPI

ci/extra_requirements.txt

@@ -1,3 +1,4 @@
 cartopy==0.24.0
 dask==2025.2.0
 shapely==2.0.7
+boto3==1.35.88

ci/test_requirements.txt

@@ -3,3 +3,4 @@ pytest==8.3.5
 pytest-mpl==0.17.0
 netCDF4==1.7.2
 coverage==7.8.0
+vcrpy==7.0.0

pyproject.toml

@@ -58,12 +58,14 @@ test = [
     "netCDF4",
     "packaging>=21.0",
     "pytest>=7.0",
-    "pytest-mpl"
+    "pytest-mpl",
+    "vcrpy>=4.3.1"
 ]
 extras = [
     "cartopy>=0.21.0",
     "dask>=2020.12.0",
-    "shapely>=1.6.4"
+    "shapely>=1.6.4",
+    "boto3>=1.26.45"
 ]
 
 [project.urls]
@@ -77,7 +79,7 @@ extras = [
 "MetPy Mondays" = "https://www.youtube.com/playlist?list=PLQut5OXpV-0ir4IdllSt1iEZKTwFBa7kO"
 
 [tool.codespell]
-skip = "*.tbl,*.ipynb,AUTHORS.txt,gempak.rst,.git,./staticdata,./docs/build,*.pdf,./talks"
+skip = "*.tbl,*.ipynb,AUTHORS.txt,gempak.rst,.git,./staticdata,./docs/build,*.pdf,./talks,./tests/remote/fixtures"
 exclude-file = ".codespellexclude"
 ignore-words = ".codespellignore"
 

src/metpy/testing.py

@@ -10,7 +10,9 @@
 import contextlib
 import functools
 from importlib.metadata import PackageNotFoundError, requires, version
+import inspect
 import operator as op
+from pathlib import Path
 import re
 
 import matplotlib.pyplot as plt
@@ -132,6 +134,23 @@ def wrapped(*args, **kwargs):
 needs_cartopy = needs_module('cartopy')
 
 
+def needs_aws(test_func):
+    """Decorate a test function that needs AWS functionality.
+
+    This both sets up recording using VCRPy as well as ensures that the the appropriate
+    AWS libraries are installed, otherwise the test is skipped.
+    """
+    # Get the vcr module this way so we can skip tests if it's not present
+    vcr = pytest.importorskip('vcr')
+
+    # Set up the fixtures relative to the test file
+    func_path = inspect.getfile(test_func)
+    fixture_path = Path(func_path).with_name('fixtures') / f'{test_func.__name__}.yaml'
+
+    # Set the cassette to use and also a wrapper function that skips the test if no boto3
+    return vcr.use_cassette(fixture_path)(needs_module('boto3')(test_func))
+
+
 @contextlib.contextmanager
 def autoclose_figure(*args, **kwargs):
     """Create a figure that is automatically closed when exiting a block.