Temporary failure in name resolution when downloading map with Cartopy

[Sendrowski]

The website Cartopy 0.18.0 uses to download its maps is rarely available, causing the plotting to fail (see issue). The problem has been fixed with version 0.19.0 but there seem to be some incompatibilities when using this version with FEEMS.

May I also ask how you obtained the triangular grids? I need a finer grid for my data.

[casparbein]

I get the same error. I have installed all dependencies and the feems package as specified (with a conda virtual environment set up etc) and popping my input files into the commands from your getting_started.ipynb notebook, everything runs until the plotting of the geographic map.

With the exact same code from the getting started notebook, I get this error:

.conda/envs/feems_e/lib/python3.8/site-packages/cartopy/io/__init__.py:260: DownloadWarning: Downloading: https://naciscdn.org/naturalearth/110m/physical/ne_110m_land.zip
  warnings.warn('Downloading: {}'.format(url), DownloadWarning)

And then:

 Traceback (most recent call last)
~/.conda/envs/feems_e/lib/python3.8/urllib/request.py in do_open(self, http_class, req, **http_conn_args)
   1353             try:
-> 1354                 h.request(req.get_method(), req.selector, req.data, headers,
   1355                           encode_chunked=req.has_header('Transfer-encoding'))

~/.conda/envs/feems_e/lib/python3.8/http/client.py in request(self, method, url, body, headers, encode_chunked)
   1255         """Send a complete request to the server."""
-> 1256         self._send_request(method, url, body, headers, encode_chunked)
   1257 

~/.conda/envs/feems_e/lib/python3.8/http/client.py in _send_request(self, method, url, body, headers, encode_chunked)
   1301             body = _encode(body, 'body')
-> 1302         self.endheaders(body, encode_chunked=encode_chunked)
   1303 

~/.conda/envs/feems_e/lib/python3.8/http/client.py in endheaders(self, message_body, encode_chunked)
   1250             raise CannotSendHeader()
-> 1251         self._send_output(message_body, encode_chunked=encode_chunked)
   1252 

~/.conda/envs/feems_e/lib/python3.8/http/client.py in _send_output(self, message_body, encode_chunked)
   1010         del self._buffer[:]
-> 1011         self.send(msg)
   1012 

~/.conda/envs/feems_e/lib/python3.8/http/client.py in send(self, data)
    950             if self.auto_open:
--> 951                 self.connect()
    952             else:

~/.conda/envs/feems_e/lib/python3.8/http/client.py in connect(self)
   1417 
-> 1418             super().connect()
   1419 

~/.conda/envs/feems_e/lib/python3.8/http/client.py in connect(self)
    921         """Connect to the host and port specified in __init__."""
--> 922         self.sock = self._create_connection(
    923             (self.host,self.port), self.timeout, self.source_address)

~/.conda/envs/feems_e/lib/python3.8/socket.py in create_connection(address, timeout, source_address)
    786     err = None
--> 787     for res in getaddrinfo(host, port, 0, SOCK_STREAM):
    788         af, socktype, proto, canonname, sa = res

~/.conda/envs/feems_e/lib/python3.8/socket.py in getaddrinfo(host, port, family, type, proto, flags)
    917     addrlist = []
--> 918     for res in _socket.getaddrinfo(host, port, family, type, proto, flags):
    919         af, socktype, proto, canonname, sa = res

gaierror: [Errno -3] Temporary failure in name resolution

During handling of the above exception, another exception occurred:

URLError                                  Traceback (most recent call last)
~/.conda/envs/feems_e/lib/python3.8/site-packages/IPython/core/formatters.py in __call__(self, obj)
    339                 pass
    340             else:
--> 341                 return printer(obj)
    342             # Finally look for special method names
    343             method = get_real_method(obj, self.print_method)

~/.conda/envs/feems_e/lib/python3.8/site-packages/IPython/core/pylabtools.py in <lambda>(fig)
    251 
    252     if 'png' in formats:
--> 253         png_formatter.for_type(Figure, lambda fig: print_figure(fig, 'png', **kwargs))
    254     if 'retina' in formats or 'png2x' in formats:
    255         png_formatter.for_type(Figure, lambda fig: retina_figure(fig, **kwargs))

~/.conda/envs/feems_e/lib/python3.8/site-packages/IPython/core/pylabtools.py in print_figure(fig, fmt, bbox_inches, **kwargs)
    135         FigureCanvasBase(fig)
    136 
--> 137     fig.canvas.print_figure(bytes_io, **kw)
    138     data = bytes_io.getvalue()
    139     if fmt == 'svg':

~/.local/lib/python3.8/site-packages/matplotlib/backend_bases.py in print_figure(self, filename, dpi, facecolor, edgecolor, orientation, format, bbox_inches, **kwargs)
   2098                            else suppress())
   2099                     with ctx:
-> 2100                         self.figure.draw(renderer)
   2101                     bbox_artists = kwargs.pop("bbox_extra_artists", None)
   2102                     bbox_inches = self.figure.get_tightbbox(renderer,

~/.local/lib/python3.8/site-packages/matplotlib/artist.py in draw_wrapper(artist, renderer, *args, **kwargs)
     36                 renderer.start_filter()
     37 
---> 38             return draw(artist, renderer, *args, **kwargs)
     39         finally:
     40             if artist.get_agg_filter() is not None:

~/.local/lib/python3.8/site-packages/matplotlib/figure.py in draw(self, renderer)
   1733 
   1734             self.patch.draw(renderer)
-> 1735             mimage._draw_list_compositing_images(
   1736                 renderer, self, artists, self.suppressComposite)
   1737 

~/.local/lib/python3.8/site-packages/matplotlib/image.py in _draw_list_compositing_images(renderer, parent, artists, suppress_composite)
    135     if not_composite or not has_images:
    136         for a in artists:
--> 137             a.draw(renderer)
    138     else:
    139         # Composite any adjacent images together

~/.local/lib/python3.8/site-packages/matplotlib/artist.py in draw_wrapper(artist, renderer, *args, **kwargs)
     36                 renderer.start_filter()
     37 
---> 38             return draw(artist, renderer, *args, **kwargs)
     39         finally:
     40             if artist.get_agg_filter() is not None:

~/.conda/envs/feems_e/lib/python3.8/site-packages/cartopy/mpl/geoaxes.py in draw(self, renderer, **kwargs)
    477         self._done_img_factory = True
    478 
--> 479         return matplotlib.axes.Axes.draw(self, renderer=renderer, **kwargs)
    480 
    481     def _update_title_position(self, renderer):

~/.local/lib/python3.8/site-packages/matplotlib/artist.py in draw_wrapper(artist, renderer, *args, **kwargs)
     36                 renderer.start_filter()
     37 
---> 38             return draw(artist, renderer, *args, **kwargs)
     39         finally:
     40             if artist.get_agg_filter() is not None:

~/.local/lib/python3.8/site-packages/matplotlib/axes/_base.py in draw(self, renderer, inframe)
   2628             renderer.stop_rasterizing()
   2629 
-> 2630         mimage._draw_list_compositing_images(renderer, self, artists)
   2631 
   2632         renderer.close_group('axes')

~/.local/lib/python3.8/site-packages/matplotlib/image.py in _draw_list_compositing_images(renderer, parent, artists, suppress_composite)
    135     if not_composite or not has_images:
    136         for a in artists:
--> 137             a.draw(renderer)
    138     else:
    139         # Composite any adjacent images together

~/.local/lib/python3.8/site-packages/matplotlib/artist.py in draw_wrapper(artist, renderer, *args, **kwargs)
     36                 renderer.start_filter()
     37 
---> 38             return draw(artist, renderer, *args, **kwargs)
     39         finally:
     40             if artist.get_agg_filter() is not None:

~/.conda/envs/feems_e/lib/python3.8/site-packages/cartopy/mpl/feature_artist.py in draw(self, renderer, *args, **kwargs)
    153         except ValueError:
    154             warnings.warn('Unable to determine extent. Defaulting to global.')
--> 155         geoms = self._feature.intersecting_geometries(extent)
    156 
    157         # Combine all the keyword args in priority order.

~/.conda/envs/feems_e/lib/python3.8/site-packages/cartopy/feature/__init__.py in intersecting_geometries(self, extent)
    300         """
    301         self.scaler.scale_from_extent(extent)
--> 302         return super(NaturalEarthFeature, self).intersecting_geometries(extent)
    303 
    304     def with_scale(self, new_scale):

~/.conda/envs/feems_e/lib/python3.8/site-packages/cartopy/feature/__init__.py in intersecting_geometries(self, extent)
    108             extent_geom = sgeom.box(extent[0], extent[2],
    109                                     extent[1], extent[3])
--> 110             return (geom for geom in self.geometries() if
    111                     geom is not None and extent_geom.intersects(geom))
    112         else:

~/.conda/envs/feems_e/lib/python3.8/site-packages/cartopy/feature/__init__.py in geometries(self)
    282         key = (self.name, self.category, self.scale)
    283         if key not in _NATURAL_EARTH_GEOM_CACHE:
--> 284             path = shapereader.natural_earth(resolution=self.scale,
    285                                              category=self.category,
    286                                              name=self.name)

~/.conda/envs/feems_e/lib/python3.8/site-packages/cartopy/io/shapereader.py in natural_earth(resolution, category, name)
    293     format_dict = {'config': config, 'category': category,
    294                    'name': name, 'resolution': resolution}
--> 295     return ne_downloader.path(format_dict)
    296 
    297 

~/.conda/envs/feems_e/lib/python3.8/site-packages/cartopy/io/__init__.py in path(self, format_dict)
    220         else:
    221             # we need to download the file
--> 222             result_path = self.acquire_resource(target_path, format_dict)
    223 
    224         return result_path

~/.conda/envs/feems_e/lib/python3.8/site-packages/cartopy/io/shapereader.py in acquire_resource(self, target_path, format_dict)
    348         url = self.url(format_dict)
    349 
--> 350         shapefile_online = self._urlopen(url)
    351 
    352         zfh = ZipFile(six.BytesIO(shapefile_online.read()), 'r')

~/.conda/envs/feems_e/lib/python3.8/site-packages/cartopy/io/__init__.py in _urlopen(self, url)
    259         """
    260         warnings.warn('Downloading: {}'.format(url), DownloadWarning)
--> 261         return urlopen(url)
    262 
    263     @staticmethod

~/.conda/envs/feems_e/lib/python3.8/urllib/request.py in urlopen(url, data, timeout, cafile, capath, cadefault, context)
    220     else:
    221         opener = _opener
--> 222     return opener.open(url, data, timeout)
    223 
    224 def install_opener(opener):

~/.conda/envs/feems_e/lib/python3.8/urllib/request.py in open(self, fullurl, data, timeout)
    523 
    524         sys.audit('urllib.Request', req.full_url, req.data, req.headers, req.get_method())
--> 525         response = self._open(req, data)
    526 
    527         # post-process response

~/.conda/envs/feems_e/lib/python3.8/urllib/request.py in _open(self, req, data)
    540 
    541         protocol = req.type
--> 542         result = self._call_chain(self.handle_open, protocol, protocol +
    543                                   '_open', req)
    544         if result:

~/.conda/envs/feems_e/lib/python3.8/urllib/request.py in _call_chain(self, chain, kind, meth_name, *args)
    500         for handler in handlers:
    501             func = getattr(handler, meth_name)
--> 502             result = func(*args)
    503             if result is not None:
    504                 return result

~/.conda/envs/feems_e/lib/python3.8/urllib/request.py in https_open(self, req)
   1395 
   1396         def https_open(self, req):
-> 1397             return self.do_open(http.client.HTTPSConnection, req,
   1398                 context=self._context, check_hostname=self._check_hostname)
   1399 

~/.conda/envs/feems_e/lib/python3.8/urllib/request.py in do_open(self, http_class, req, **http_conn_args)
   1355                           encode_chunked=req.has_header('Transfer-encoding'))
   1356             except OSError as err: # timeout error
-> 1357                 raise URLError(err)
   1358             r = h.getresponse()
   1359         except:

URLError: <urlopen error [Errno -3] Temporary failure in name resolution>

<Figure size 1800x1200 with 1 Axes>

That is a very long error message and I have no clue what I have to change to get it to run. I am running feems from a remote machine and have to connect to it with a VPN.

I'd appreciate any kind of help or tips.
Cheers,
Bernhard