[mwclient#79] Improve error msg for invalid json response

Author: danmichaelo

mwclient/client.py

@@ -313,7 +313,7 @@ def raw_api(self, action, *args, **kwargs):
         except ValueError:
             if res.startswith('MediaWiki API is not enabled for this site.'):
                 raise errors.APIDisabledError
-            raise ValueError('Could not decode JSON: %s' % res)
+            raise errors.InvalidResponse(res)
 
     def raw_index(self, action, *args, **kwargs):
         """Sends a call to index.php rather than the API."""

mwclient/errors.py

@@ -56,3 +56,16 @@ class NoSpecifiedEmail(EmailError):
 
 class NoWriteApi(MwClientError):
     pass
+
+
+class InvalidResponse(MwClientError):
+
+    def __init__(self, response_text=None):
+        self.message = 'Did not get a valid JSON response from the server. Check that ' + \
+                       'you used the correct hostname. If you did, the server might ' + \
+                       'be wrongly configured or experience temporary problems.'
+        self.response_text = response_text
+        MwClientError.__init__(self, self.message, response_text)
+
+    def __str__(self):
+        return self.message