Use pooch instead of bundling standard name table (#436)

* Use pooch instead of bundling standard name table

* fix

* Skip pooch in mypy

* Make pooch more optionall

* Minor fixes

Author: dcherian

cf_xarray/accessor.py

@@ -2023,7 +2023,7 @@ def add_canonical_attributes(
             Print added attributes to screen.
         source : optional
             Path of `cf-standard-name-table.xml` or file object containing XML data.
-            If ``None``, use the default version associated with ``cf-xarray``.
+            If ``None``, use the latest CF standard name table (requires ``pooch``).
 
         Returns
         -------

cf_xarray/data/cf-standard-name-table.xml

@@ -67,5 +67,6 @@ def LooseVersion(vstring):
 has_scipy, requires_scipy = _importorskip("scipy")
 has_shapely, requires_shapely = _importorskip("shapely")
 has_pint, requires_pint = _importorskip("pint")
+has_pooch, requires_pooch = _importorskip("pooch")
 _, requires_rich = _importorskip("rich")
 has_regex, requires_regex = _importorskip("regex")

cf_xarray/tests/__init__.py

@@ -2,7 +2,6 @@
 import pickle
 import warnings
 from textwrap import dedent
-from urllib.request import urlopen
 
 import matplotlib as mpl
 import numpy as np
@@ -41,6 +40,7 @@
     raise_if_dask_computes,
     requires_cftime,
     requires_pint,
+    requires_pooch,
     requires_regex,
     requires_rich,
     requires_scipy,
@@ -1698,14 +1698,9 @@ def test_regex_match():
         assert_identical(ds.cf["temp"], ds["Tempblah"])
 
 
+@requires_pooch
 def test_cf_standard_name_table_version() -> None:
-    url = (
-        "https://raw.githubusercontent.com/cf-convention/cf-convention.github.io/"
-        "master/Data/cf-standard-names/current/src/cf-standard-name-table.xml"
-    )
-    expected_info, _, _ = parse_cf_standard_name_table(urlopen(url))
-    actual_info, _, _ = parse_cf_standard_name_table()
-    assert expected_info == actual_info
+    parse_cf_standard_name_table()
 
 
 def test_add_canonical_attributes_0_dim() -> None:

cf_xarray/tests/test_accessor.py

@@ -1,4 +1,3 @@
-import os
 from collections import defaultdict
 from typing import Any, Dict, Iterable
 from xml.etree import ElementTree
@@ -83,8 +82,12 @@ def parse_cf_standard_name_table(source=None):
     """"""
 
     if not source:
-        source = os.path.join(
-            os.path.dirname(__file__), "data", "cf-standard-name-table.xml"
+        import pooch
+
+        source = pooch.retrieve(
+            "https://raw.githubusercontent.com/cf-convention/cf-convention.github.io/"
+            "master/Data/cf-standard-names/current/src/cf-standard-name-table.xml",
+            known_hash=None,
         )
     root = ElementTree.parse(source).getroot()
 

cf_xarray/utils.py

@@ -15,6 +15,7 @@ dependencies:
   - pooch
   - regex
   - rich
+  - pooch
   - scipy
   - shapely
   - xarray

ci/environment.yml

@@ -22,7 +22,7 @@ dependencies = [
 dynamic = ["version"]
 
 [project.optional-dependencies]
-all = ["matplotlib", "pint", "shapely", "regex", "rich"]
+all = ["matplotlib", "pint", "shapely", "regex", "rich", "pooch"]
 
 [project.urls]
 homepage = "https://cf-xarray.readthedocs.io"
@@ -41,7 +41,7 @@ requires = [
 build-backend = "setuptools.build_meta"
 
 [tool.setuptools]
-packages = ["cf_xarray", "cf_xarray.data", "cf_xarray.scripts"]
+packages = ["cf_xarray", "cf_xarray.scripts"]
 
 [tool.setuptools.exclude-package-data]
 cf_xarray = ["tests/*"]
@@ -129,6 +129,7 @@ warn_unused_ignores = true
 module=[
     "cftime",
     "pandas",
+    "pooch",
     "matplotlib",
     "pytest",
     "shapely.geometry",