Deal with Radicale 0.7

Fix #138

docs/supported.rst

@@ -48,7 +48,8 @@ Radicale
 --------
 
 Vdirsyncer is tested against the git version and the latest PyPI release of
-Radicale.
+Radicale. Versions ``<= 0.7`` have substantial deficiencies, and using them is
+neither supported nor encouraged.
 
 - Radicale doesn't `support time ranges in the calendar-query of CalDAV
   <https://github.com/Kozea/Radicale/issues/146>`_, so setting ``start_date``

tests/storage/dav/servers/radicale/__init__.py

@@ -59,14 +59,19 @@ def do_the_radicale_dance(tmpdir):
     import radicale.config
 
     # Now we can set some basic configuration.
-    radicale.config.set('rights', 'type', 'owner_only')
-    radicale.config.set('auth', 'type', 'http')
+    # Radicale <=0.7 doesn't work with this, therefore we just catch the
+    # exception and assume Radicale is open for everyone.
+    try:
+        radicale.config.set('rights', 'type', 'owner_only')
+        radicale.config.set('auth', 'type', 'http')
 
-    import radicale.auth.http
+        import radicale.auth.http
 
-    def is_authenticated(user, password):
-        return user == 'bob' and password == 'bob'
-    radicale.auth.http.is_authenticated = is_authenticated
+        def is_authenticated(user, password):
+            return user == 'bob' and password == 'bob'
+        radicale.auth.http.is_authenticated = is_authenticated
+    except Exception as e:
+        print(e)
 
     if storage_backend == 'filesystem':
         radicale.config.set('storage', 'type', 'filesystem')

vdirsyncer/storage/dav.py

@@ -419,9 +419,14 @@ class DavStorage(Storage):
 
             contenttype = prop.find('{DAV:}getcontenttype').text
 
-            etag = prop.find('{DAV:}getetag').text
             href = self._normalize_href(element.find('{DAV:}href').text)
-            if self.item_mimetype not in contenttype:
+            etag = prop.find('{DAV:}getetag').text
+            if not etag:
+                raise ValueError('Server did not return an etag for item {}. '
+                                 'Vdirsyncer is unable to function without '
+                                 'one.'.format(href))
+
+            if not contenttype or self.item_mimetype not in contenttype:
                 dav_logger.debug(
                     'Skipping item with href {!r} '
                     'because content type {!r} != {!r}.'