Fixes #36 Fix functionality for multiple Conventions, and when Conventions does not mention CF

Changelog.rst

@@ -11,6 +11,9 @@ version 1.8.4
   messages are displayed globally, i.e. to change the project-wide verbosity.
 * Changed behaviour and default of `verbose` keyword argument when available
   to a function/method so it interfaces with the new logging functionality.
+* Fixed bug the wouldn't allow the reading of a netCDF file which
+  specifies Conventions other than CF
+  (https://github.com/NCAS-CMS/cfdm/issues/36).
 
 version 1.8.3
 -------------

cfdm/read_write/netcdf/netcdfread.py

@@ -675,9 +675,19 @@ def read(self, filename, extra=None, default_version=None,
         # ------------------------------------------------------------
         # Find the CF version for the file
         # ------------------------------------------------------------
-        # DCH ALERT: haven't yet dealt with multiple conventions! TODO
-        file_version = g['global_attributes'].get('Conventions', '').replace(
-            'CF-', '', 1)
+        Conventions =  g['global_attributes'].get('Conventions', '')
+
+        all_conventions = re.split(',', Conventions)
+        if all_conventions[0] == Conventions:
+            all_conventions = re.split('\s+', Conventions)
+
+        file_version = None
+        for c in all_conventions:
+            if not re.match('^CF-\d', c):
+                continue
+
+            file_version = re.sub('^CF-', '', c)
+
         if not file_version:
             if default_version is not None:
                 # Assume the default version provided by the user

cfdm/test/test_read_write.py

@@ -52,13 +52,14 @@ def setUp(self):
             os.path.dirname(os.path.abspath(__file__)), 'string_char.nc')
 
         self.test_only = []
-        #    self.test_only = ['NOTHING!!!!!']
-        #    self.test_only = ['test_read_CDL']
-        #    self.test_only = ['test_write_filename']
-        #    self.test_only = ['test_read_write_unlimited']
-        #    self.test_only = ['test_read_field']
-        #    self.test_only = ['test_read_mask']
-        #    self.test_only = ['test_read_write_format']
+        # self.test_only = ['NOTHING!!!!!']
+        # self.test_only = ['test_read_CDL']
+        # self.test_only = ['test_write_filename']
+        # self.test_only = ['test_read_write_unlimited']
+        # self.test_only = ['test_read_field']
+        # self.test_only = ['test_read_mask']
+        # self.test_only = ['test_read_write_format']
+        # self.test_only = ['test_read_write_Conventions']
 
     def test_write_filename(self):
         if self.test_only and inspect.stack()[0][3] not in self.test_only:
@@ -359,6 +360,55 @@ def test_read_write_string(self):
                             self.assertTrue(i.equals(j, verbose=3))
         #--- End: for
 
+    def test_read_write_Conventions(self):
+        if self.test_only and inspect.stack()[0][3] not in self.test_only:
+            return
+
+        f = cfdm.read(self.filename)[0]
+
+        version = 'CF-' + cfdm.CF()
+        other = 'ACDD-1.3'
+
+        for Conventions in (other,):
+            cfdm.write(f, tmpfile0, Conventions=Conventions)
+            g = cfdm.read(tmpfile0)[0]
+            self.assertTrue(
+                g.get_property('Conventions') == ' '.join([version, other]),
+                "{!r}, {!r}".format(
+                    g.get_property('Conventions'), Conventions))
+
+        for Conventions in (version,
+                            '',
+                            ' ',
+                            ',',
+                            ', ',
+                            ):
+            Conventions = version
+            cfdm.write(f, tmpfile0, Conventions=Conventions)
+            g = cfdm.read(tmpfile0)[0]
+            self.assertTrue(g.get_property('Conventions') == version,
+                            "{!r}, {!r}".format(
+                                g.get_property('Conventions'),
+                                Conventions))
+
+        for Conventions in ([version],                          
+                            [version, other],
+        ):
+            cfdm.write(f, tmpfile0, Conventions=Conventions)
+            g = cfdm.read(tmpfile0)[0]
+            self.assertTrue(
+                g.get_property('Conventions') == ' '.join(Conventions),
+                "{!r}, {!r}".format(
+                    g.get_property('Conventions'), Conventions))
+
+        for Conventions in ([other, version],):
+            cfdm.write(f, tmpfile0, Conventions=Conventions)
+            g = cfdm.read(tmpfile0)[0]
+            self.assertTrue(
+                g.get_property('Conventions') == ' '.join([version, other]),
+                "{!r}, {!r}".format(
+                    g.get_property('Conventions'), Conventions))
+
 #--- End: class
 
 if __name__ == "__main__":