Drop 'six' from dependencies

As we no longer support Python 2, there is no reason to
keep this dependency. This commit removes all usages
of six and removes it from dependencies.

Author: Lorak-mmk

benchmarks/callback_full_pipeline.py

@@ -18,7 +18,6 @@
 from threading import Event
 
 from base import benchmark, BenchmarkThread
-from six.moves import range
 
 log = logging.getLogger(__name__)
 

benchmarks/future_batches.py

@@ -14,7 +14,7 @@
 
 import logging
 from base import benchmark, BenchmarkThread
-from six.moves import queue
+import queue
 
 log = logging.getLogger(__name__)
 

benchmarks/future_full_pipeline.py

@@ -14,7 +14,7 @@
 
 import logging
 from base import benchmark, BenchmarkThread
-from six.moves import queue
+import queue
 
 log = logging.getLogger(__name__)
 

benchmarks/sync.py

@@ -13,7 +13,6 @@
 # limitations under the License.
 
 from base import benchmark, BenchmarkThread
-from six.moves import range
 
 
 class Runner(BenchmarkThread):

cassandra/auth.py

@@ -32,8 +32,6 @@
 except ImportError:
     SASLClient = None
 
-import six
-
 log = logging.getLogger(__name__)
 
 # Custom payload keys related to DSE Unified Auth
@@ -270,15 +268,15 @@ def __init__(self, username, password):
         self.password = password
 
     def get_mechanism(self):
-        return six.b("PLAIN")
+        return b"PLAIN"
 
     def get_initial_challenge(self):
-        return six.b("PLAIN-START")
+        return b"PLAIN-START"
 
     def evaluate_challenge(self, challenge):
-        if challenge == six.b('PLAIN-START'):
+        if challenge == b'PLAIN-START':
             data = "\x00%s\x00%s" % (self.username, self.password)
-            return data if six.PY2 else data.encode()
+            return data.encode()
         raise Exception('Did not receive a valid challenge response from server')
 
 
@@ -297,13 +295,13 @@ def __init__(self, host, service, qops, properties):
         self.sasl = SASLClient(host, service, 'GSSAPI', qops=qops, **properties)
 
     def get_mechanism(self):
-        return six.b("GSSAPI")
+        return b"GSSAPI"
 
     def get_initial_challenge(self):
-        return six.b("GSSAPI-START")
+        return b"GSSAPI-START"
 
     def evaluate_challenge(self, challenge):
-        if challenge == six.b('GSSAPI-START'):
+        if challenge == b'GSSAPI-START':
             return self.sasl.process()
         else:
             return self.sasl.process(challenge)

cassandra/cluster.py

@@ -21,6 +21,7 @@
 import atexit
 from binascii import hexlify
 from collections import defaultdict
+from collections.abc import Mapping
 from concurrent.futures import ThreadPoolExecutor, FIRST_COMPLETED, wait as wait_futures
 from copy import copy
 from functools import partial, wraps
@@ -30,8 +31,7 @@
 from warnings import warn
 from random import random
 import re
-import six
-from six.moves import filter, range, queue as Queue
+import queue
 import socket
 import sys
 import time
@@ -82,7 +82,6 @@
 from cassandra.marshal import int64_pack
 from cassandra.tablets import Tablet, Tablets
 from cassandra.timestamps import MonotonicTimestampGenerator
-from cassandra.compat import Mapping
 from cassandra.util import _resolve_contact_points_to_string_map, Version
 
 from cassandra.datastax.insights.reporter import MonitorReporter
@@ -113,9 +112,6 @@
 except ImportError:
     from cassandra.util import WeakSet  # NOQA
 
-if six.PY3:
-    long = int
-
 def _is_eventlet_monkey_patched():
     if 'eventlet.patcher' not in sys.modules:
         return False
@@ -1219,7 +1215,7 @@ def __init__(self,
             else:
                 self._contact_points_explicit = True
 
-            if isinstance(contact_points, six.string_types):
+            if isinstance(contact_points, str):
                 raise TypeError("contact_points should not be a string, it should be a sequence (e.g. list) of strings")
 
             if None in contact_points:
@@ -1882,8 +1878,8 @@ def _new_session(self, keyspace):
         return session
 
     def _session_register_user_types(self, session):
-        for keyspace, type_map in six.iteritems(self._user_types):
-            for udt_name, klass in six.iteritems(type_map):
+        for keyspace, type_map in self._user_types.items():
+            for udt_name, klass in type_map.items():
                 session.user_type_registered(keyspace, udt_name, klass)
 
     def _cleanup_failed_on_up_handling(self, host):
@@ -2767,7 +2763,7 @@ def execute_async(self, query, parameters=None, trace=False, custom_payload=None
         """
         custom_payload = custom_payload if custom_payload else {}
         if execute_as:
-            custom_payload[_proxy_execute_key] = six.b(execute_as)
+            custom_payload[_proxy_execute_key] = execute_as.encode()
 
         future = self._create_response_future(
             query, parameters, trace, custom_payload, timeout,
@@ -2831,8 +2827,8 @@ def execute_graph_async(self, query, parameters=None, trace=False, execution_pro
 
         custom_payload = execution_profile.graph_options.get_options_map()
         if execute_as:
-            custom_payload[_proxy_execute_key] = six.b(execute_as)
-        custom_payload[_request_timeout_key] = int64_pack(long(execution_profile.request_timeout * 1000))
+            custom_payload[_proxy_execute_key] = execute_as.encode()
+        custom_payload[_request_timeout_key] = int64_pack(int(execution_profile.request_timeout * 1000))
 
         future = self._create_response_future(query, parameters=None, trace=trace, custom_payload=custom_payload,
                                               timeout=_NOT_SET, execution_profile=execution_profile)
@@ -2969,7 +2965,7 @@ def _create_response_future(self, query, parameters, trace, custom_payload,
 
         prepared_statement = None
 
-        if isinstance(query, six.string_types):
+        if isinstance(query, str):
             query = SimpleStatement(query)
         elif isinstance(query, PreparedStatement):
             query = query.bind(parameters)
@@ -3437,10 +3433,6 @@ def user_type_registered(self, keyspace, user_type, klass):
                 'User type %s does not exist in keyspace %s' % (user_type, keyspace))
 
         field_names = type_meta.field_names
-        if six.PY2:
-            # go from unicode to string to avoid decode errors from implicit
-            # decode when formatting non-ascii values
-            field_names = [fn.encode('utf-8') for fn in field_names]
 
         def encode(val):
             return '{ %s }' % ' , '.join('%s : %s' % (
@@ -4208,7 +4200,7 @@ def _get_schema_mismatches(self, peers_result, local_result, local_address):
             log.debug("[control connection] Schemas match")
             return None
 
-        return dict((version, list(nodes)) for version, nodes in six.iteritems(versions))
+        return dict((version, list(nodes)) for version, nodes in versions.items())
 
     def _get_peers_query(self, peers_query_type, connection=None):
         """
@@ -4327,7 +4319,7 @@ class _Scheduler(Thread):
     is_shutdown = False
 
     def __init__(self, executor):
-        self._queue = Queue.PriorityQueue()
+        self._queue = queue.PriorityQueue()
         self._scheduled_tasks = set()
         self._count = count()
         self._executor = executor
@@ -4385,7 +4377,7 @@ def run(self):
                     else:
                         self._queue.put_nowait((run_at, i, task))
                         break
-            except Queue.Empty:
+            except queue.Empty:
                 pass
 
             time.sleep(0.1)

cassandra/compat.py

@@ -16,8 +16,6 @@
 from collections import namedtuple
 from heapq import heappush, heappop
 from itertools import cycle
-import six
-from six.moves import xrange, zip
 from threading import Condition
 import sys
 
@@ -119,7 +117,7 @@ def execute(self, concurrency, fail_fast):
         self._current = 0
         self._exec_count = 0
         with self._condition:
-            for n in xrange(concurrency):
+            for n in range(concurrency):
                 if not self._execute_next():
                     break
         return self._results()
@@ -143,17 +141,13 @@ def _execute(self, idx, statement, params):
                 callback=self._on_success, callback_args=args,
                 errback=self._on_error, errback_args=args)
         except Exception as exc:
-            # exc_info with fail_fast to preserve stack trace info when raising on the client thread
-            # (matches previous behavior -- not sure why we wouldn't want stack trace in the other case)
-            e = sys.exc_info() if self._fail_fast and six.PY2 else exc
-
             # If we're not failing fast and all executions are raising, there is a chance of recursing
             # here as subsequent requests are attempted. If we hit this threshold, schedule this result/retry
             # and let the event loop thread return.
             if self._exec_depth < self.max_error_recursion:
-                self._put_result(e, idx, False)
+                self._put_result(exc, idx, False)
             else:
-                self.session.submit(self._put_result, e, idx, False)
+                self.session.submit(self._put_result, exc, idx, False)
         self._exec_depth -= 1
 
     def _on_success(self, result, future, idx):
@@ -163,14 +157,6 @@ def _on_success(self, result, future, idx):
     def _on_error(self, result, future, idx):
         self._put_result(result, idx, False)
 
-    @staticmethod
-    def _raise(exc):
-        if six.PY2 and isinstance(exc, tuple):
-            (exc_type, value, traceback) = exc
-            six.reraise(exc_type, value, traceback)
-        else:
-            raise exc
-
 
 class ConcurrentExecutorGenResults(_ConcurrentExecutor):
 
@@ -190,7 +176,7 @@ def _results(self):
                     try:
                         self._condition.release()
                         if self._fail_fast and not res[0]:
-                            self._raise(res[1])
+                            raise res[1]
                         yield res
                     finally:
                         self._condition.acquire()
@@ -221,9 +207,9 @@ def _results(self):
             while self._current < self._exec_count:
                 self._condition.wait()
                 if self._exception and self._fail_fast:
-                    self._raise(self._exception)
+                    raise self._exception
         if self._exception and self._fail_fast:  # raise the exception even if there was no wait
-            self._raise(self._exception)
+            raise self._exception
         return [r[1] for r in sorted(self._results_queue)]
 
 

cassandra/concurrent.py

@@ -19,8 +19,6 @@
 from heapq import heappush, heappop
 import io
 import logging
-import six
-from six.moves import range
 import socket
 import struct
 import sys
@@ -36,7 +34,7 @@
 if 'gevent.monkey' in sys.modules:
     from gevent.queue import Queue, Empty
 else:
-    from six.moves.queue import Queue, Empty  # noqa
+    from queue import Queue, Empty  # noqa
 
 from cassandra import ConsistencyLevel, AuthenticationFailed, OperationTimedOut, ProtocolVersion
 from cassandra.marshal import int32_pack
@@ -613,12 +611,6 @@ def wrapper(self, *args, **kwargs):
 
 DEFAULT_CQL_VERSION = '3.0.0'
 
-if six.PY3:
-    def int_from_buf_item(i):
-        return i
-else:
-    int_from_buf_item = ord
-
 
 class _ConnectionIOBuffer(object):
     """
@@ -1164,7 +1156,7 @@ def _read_frame_header(self):
         buf = self._io_buffer.cql_frame_buffer.getvalue()
         pos = len(buf)
         if pos:
-            version = int_from_buf_item(buf[0]) & PROTOCOL_VERSION_MASK
+            version = buf[0] & PROTOCOL_VERSION_MASK
             if version not in ProtocolVersion.SUPPORTED_VERSIONS:
                 raise ProtocolError("This version of the driver does not support protocol version %d" % version)
             frame_header = frame_header_v3 if version >= 3 else frame_header_v1_v2
@@ -1367,7 +1359,7 @@ def _handle_options_response(self, options_response):
                           remote_supported_compressions)
             else:
                 compression_type = None
-                if isinstance(self.compression, six.string_types):
+                if isinstance(self.compression, str):
                     # the user picked a specific compression type ('snappy' or 'lz4')
                     if self.compression not in remote_supported_compressions:
                         raise ProtocolError(

cassandra/connection.py

@@ -12,9 +12,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-import six
-
-
 # Caching constants.
 CACHING_ALL = "ALL"
 CACHING_KEYS_ONLY = "KEYS_ONLY"
@@ -31,7 +28,4 @@ class ValidationError(CQLEngineException):
 
 
 class UnicodeMixin(object):
-    if six.PY3:
-        __str__ = lambda x: x.__unicode__()
-    else:
-        __str__ = lambda x: six.text_type(x).encode('utf-8')
+    __str__ = lambda x: x.__unicode__()