Add timeout argument to _query method

Default value is None, so the current default behavior remains unchanged

krakenex/api.py

@@ -92,7 +92,7 @@ def load_key(self, path):
             self.secret = f.readline().strip()
         return
 
-    def _query(self, urlpath, data, headers=None):
+    def _query(self, urlpath, data, headers=None, timeout=None):
         """ Low-level query handling.
 
         .. note::
@@ -105,6 +105,9 @@ def _query(self, urlpath, data, headers=None):
         :type data: dict
         :param headers: (optional) HTTPS headers
         :type headers: dict
+        :param timeout: (optional) if not None, a `requests.HTTPError` will be 
+        thrown after `timeout` seconds if a response has not been received
+        :type timeout: number
         :returns: :py:meth:`requests.Response.json`-deserialised Python object
         :raises: :py:exc:`requests.HTTPError`: if response status not successful
 
@@ -116,7 +119,8 @@ def _query(self, urlpath, data, headers=None):
 
         url = self.uri + urlpath
 
-        self.response = self.session.post(url, data = data, headers = headers)
+        self.response = self.session.post(url, data = data, headers = headers, 
+                                          timeout = timeout)
 
         if self.response.status_code not in (200, 201, 202):
             self.response.raise_for_status()