Add parsing TABLETS_ROUTING_V1 extension to ProtocolFeatures

In order for Scylla to send the tablet info, the driver must tell
the database during connection handshake that it is able to
interpret it. This negotation is added as a part of ProtocolFeatures
class.

Author: sylwiaszunejko

cassandra/protocol_features.py

@@ -6,22 +6,26 @@
 
 
 RATE_LIMIT_ERROR_EXTENSION = "SCYLLA_RATE_LIMIT_ERROR"
+TABLETS_ROUTING_V1 = "TABLETS_ROUTING_V1"
 
 class ProtocolFeatures(object):
     rate_limit_error = None
     shard_id = 0
     sharding_info = None
+    tablets_routing_v1 = False
 
-    def __init__(self, rate_limit_error=None, shard_id=0, sharding_info=None):
+    def __init__(self, rate_limit_error=None, shard_id=0, sharding_info=None, tablets_routing_v1=False):
         self.rate_limit_error = rate_limit_error
         self.shard_id = shard_id
         self.sharding_info = sharding_info
+        self.tablets_routing_v1 = tablets_routing_v1
 
     @staticmethod
     def parse_from_supported(supported):
         rate_limit_error = ProtocolFeatures.maybe_parse_rate_limit_error(supported)
         shard_id, sharding_info = ProtocolFeatures.parse_sharding_info(supported)
-        return ProtocolFeatures(rate_limit_error, shard_id, sharding_info)
+        tablets_routing_v1 = ProtocolFeatures.parse_tablets_info(supported)
+        return ProtocolFeatures(rate_limit_error, shard_id, sharding_info, tablets_routing_v1)
 
     @staticmethod
     def maybe_parse_rate_limit_error(supported):
@@ -43,6 +47,8 @@ def get_cql_extension_field(vals, key):
     def add_startup_options(self, options):
         if self.rate_limit_error is not None:
             options[RATE_LIMIT_ERROR_EXTENSION] = ""
+        if self.tablets_routing_v1:
+            options[TABLETS_ROUTING_V1] = ""
 
     @staticmethod
     def parse_sharding_info(options):
@@ -63,3 +69,6 @@ def parse_sharding_info(options):
                                             shard_aware_port, shard_aware_port_ssl)
 
 
+    @staticmethod
+    def parse_tablets_info(options):
+        return TABLETS_ROUTING_V1 in options