Replace urllib.request with urllib3 to support WebAssembly

environment.yml

@@ -14,6 +14,7 @@ dependencies:
   - pyshp>=2.3
   - pyproj>=3.3.1
   - packaging>=21
+  - urllib3>=2.3
   # The testing label has the proper version of freetype included
   - conda-forge/label/testing::matplotlib-base>=3.6
 

lib/cartopy/io/__init__.py

@@ -13,9 +13,10 @@
 import collections
 from pathlib import Path
 import string
-from urllib.request import urlopen
 import warnings
 
+from urllib3 import request
+
 from cartopy import config
 
 
@@ -227,6 +228,7 @@ def acquire_resource(self, target_path, format_dict):
         response = self._urlopen(url)
 
         target_path.write_bytes(response.read())
+        response.release_conn()
 
         return target_path
 
@@ -238,7 +240,7 @@ def _urlopen(self, url):
 
         """
         warnings.warn(f'Downloading: {url}', DownloadWarning)
-        return urlopen(url)
+        return request('GET', url, preload_content=False)
 
     @staticmethod
     def from_config(specification, config_dict=None):

lib/cartopy/io/img_tiles.py

@@ -202,7 +202,8 @@ def _image_url(self, tile):
         pass
 
     def get_image(self, tile):
-        from urllib.request import HTTPError, Request, URLError, urlopen
+        from urllib3 import request
+        from urllib3.exceptions import HTTPError
 
         if self.cache_path is not None:
             filename = "_".join([str(i) for i in tile]) + ".npy"
@@ -215,13 +216,13 @@ def get_image(self, tile):
         else:
             url = self._image_url(tile)
             try:
-                request = Request(url, headers={"User-Agent": self.user_agent})
-                fh = urlopen(request)
-                im_data = io.BytesIO(fh.read())
-                fh.close()
+                r = request('GET', url, headers={"User-Agent": self.user_agent},
+                            preload_content=False)
+                im_data = io.BytesIO(r.read())
+                r.release_conn()
                 img = Image.open(im_data)
 
-            except (HTTPError, URLError) as err:
+            except HTTPError as err:
                 print(err)
                 img = Image.fromarray(np.full((256, 256, 3), (250, 250, 250),
                                               dtype=np.uint8))

lib/cartopy/io/ogc_clients.py

@@ -19,14 +19,14 @@
 import io
 import math
 from pathlib import Path
-from urllib.parse import urlparse
 import warnings
 import weakref
 from xml.etree import ElementTree
 
 import numpy as np
 from PIL import Image
 import shapely.geometry as sgeom
+from urllib3.util import parse_url
 
 import cartopy
 
@@ -753,7 +753,7 @@ def __init__(self, service, features, getfeature_extra_kwargs=None):
             # agroenvgeo.data.inra.fr from full address
             # http://mapserver.gis.umn.edu/mapserver
             # or https://agroenvgeo.data.inra.fr:443/geoserver/wfs
-            self.url = urlparse(service).hostname
+            self.url = parse_url(service).hostname
             # WebFeatureService of owslib
             service = WebFeatureService(service)
         else:

lib/cartopy/io/shapereader.py

@@ -30,10 +30,10 @@
 import io
 import itertools
 from pathlib import Path
-from urllib.error import HTTPError
 
 import shapefile
 import shapely.geometry as sgeom
+from urllib3.exceptions import HTTPError
 
 from cartopy import config
 from cartopy.io import Downloader

lib/cartopy/io/srtm.py

@@ -401,10 +401,11 @@ def _create_srtm_mask(resolution, filename=None):
         # dependencies of cartopy.
         from bs4 import BeautifulSoup
         if filename is None:
-            from urllib.request import urlopen
+            from urllib3 import request
             url = SRTMDownloader._SRTM_BASE_URL.format(resolution=resolution)
-            with urlopen(url) as f:
-                html = f.read()
+            with request('GET', url, preload_content=False) as r:
+                html = r.read()
+                r.release_conn()
         else:
             html = Path(filename).read_text()
 

pyproject.toml

@@ -51,6 +51,7 @@ dependencies = [
     "packaging>=21",
     "pyshp>=2.3",
     "pyproj>=3.3.1",
+    "urllib3>=2.3"
 ]
 dynamic = ["version"]