Added tailable_cursor and await_data query options to OP_QUERY

asyncio_mongo/protocol.py

@@ -23,6 +23,10 @@ from asyncio_mongo.log import logger
 
 _ONE = b"\x01\x00\x00\x00"
 _ZERO = b"\x00\x00\x00\x00"
+_QUERY_OPTIONS = {
+    "tailable_cursor": 2,
+    "oplog_replay": 8,
+    "await_data": 32}
 
 """Low level connection to Mongo."""
 
@@ -163,14 +167,22 @@ class MongoProtocol(asyncio.Protocol):
         message = struct.pack("<iq", limit, cursor_id)
         self.send_message(2005, collection, message)
 
-    def OP_QUERY(self, collection, spec, skip, limit, fields=None):
+    def OP_QUERY(self, collection, spec, skip, limit, fields=None,
+                 tailable=False, await_data=False):
         message = struct.pack("<ii", skip, limit) + bson.BSON.encode(spec)
         if fields:
             message += bson.BSON.encode(fields)
 
+        query_opts = 0
+        if tailable:
+            query_opts |= _QUERY_OPTIONS["tailable_cursor"]
+        if tailable and await_data:
+            query_opts |= _QUERY_OPTIONS["await_data"]
+        query_opts = struct.pack("<i", query_opts)
+
         query = _MongoQuery(self.__id, collection, limit)
         self.__queries[self.__id] = query
-        self.send_message(2004, collection, message)
+        self.send_message(2004, collection, message, query_opts)
         return query.future
 
     def query_failure(self, request_id, cursor_id, response, raw_error):