Merge pull request #269 from davidhassell/read-https

Fix bug that prevents "https://" netCDF files from being read

Changelog.rst

@@ -1,3 +1,13 @@
+Version 1.10.1.2
+----------------
+
+**2023-08-31**
+
+* Fix bug that prevented "https://" netCDF files from being read
+  (https://github.com/NCAS-CMS/cfdm/issues/268)
+
+----
+
 Version 1.10.1.1
 ----------------
 

cfdm/read_write/netcdf/netcdfread.py

@@ -481,8 +481,10 @@ def cdl_to_netcdf(cls, filename):
     def is_netcdf_file(cls, filename):
         """Return `True` if the file is a netCDF file.
 
-        Note that the file type is determined by inspecting the file's
-        contents and any file suffix is not not considered.
+        The file type is determined by inspecting the file's contents
+        and any file suffix is not not considered. However, file names
+        starting ``https://`` or ``http://`` are assumed, without
+        checking, to be netCDF files.
 
         :Parameters:
 
@@ -501,7 +503,7 @@ def is_netcdf_file(cls, filename):
 
         """
         # Assume that URLs are in netCDF format
-        if filename.startswith("http://"):
+        if filename.startswith("https://") or filename.startswith("http://"):
             return True
 
         # Read the magic number

cfdm/test/test_read_write.py

@@ -985,12 +985,11 @@ def test_read_write_domain_ancillary(self):
 
     def test_read_url(self):
         """Test reading urls."""
-        remote = "http://psl.noaa.gov/thredds/dodsC/Datasets/cru/crutem5/Monthlies/air.mon.anom.nobs.nc"
-        # Check that the file remote is indeed accesible
-        _ = netCDF4.Dataset(remote, "r")
-        # Check that cfdm can access it
-        f = cfdm.read(remote)
-        self.assertEqual(len(f), 1)
+        for scheme in ("http", "https"):
+            remote = f"{scheme}://psl.noaa.gov/thredds/dodsC/Datasets/cru/crutem5/Monthlies/air.mon.anom.nobs.nc"
+            # Check that cfdm can access it
+            f = cfdm.read(remote)
+            self.assertEqual(len(f), 1)
 
 
 if __name__ == "__main__":