adding experimental __slots__ to some classes (#368)

* adding experimental __slots__ to some classes

* adding more experimental __slots__ to some classes

* remove redundant slots

* added more experimental slots to classes

* remove slots from buffer class

6 files changed, 81 insertions, 0 deletions

diff --git a/amqp/abstract_channel.py b/amqp/abstract_channel.py
index 6234b19..ae95a89 100644
--- a/amqp/abstract_channel.py
+++ b/amqp/abstract_channel.py
@@ -39,6 +39,19 @@ class AbstractChannel:
 
         self._setup_listeners()
 
+    __slots__ = (
+        "is_closing",
+        "connection",
+        "channel_id",
+        "method_queue",
+        "auto_decode",
+        "_pending",
+        "_callbacks",
+        # adding '__dict__' to get dynamic assignment
+        "__dict__",
+        "__weakref__",
+        )
+
     def __enter__(self):
         return self
 
diff --git a/amqp/basic_message.py b/amqp/basic_message.py
index 222d366..cee0515 100644
--- a/amqp/basic_message.py
+++ b/amqp/basic_message.py
@@ -107,6 +107,12 @@ class Message(GenericContent):
         self.body = body
         self.channel = channel
 
+    __slots__ = (
+        "delivery_info",
+        "body",
+        "channel",
+        )
+
     @property
     def headers(self):
         return self.properties.get('application_headers')
diff --git a/amqp/channel.py b/amqp/channel.py
index 77cfaab..fffc7b8 100644
--- a/amqp/channel.py
+++ b/amqp/channel.py
@@ -122,6 +122,18 @@ class Channel(AbstractChannel):
         if self.connection.confirm_publish:
             self.basic_publish = self.basic_publish_confirm
 
+        __slots__ = (
+        "is_open",
+        "active",
+        "returned_messages",
+        "callbacks",
+        "cancel_callbacks",
+        "events",
+        "no_ack_consumers",
+        "on_open",
+        "_confirm_selected",
+        )
+
     def then(self, on_success, on_error=None):
         return self.on_open.then(on_success, on_error)
 
diff --git a/amqp/sasl.py b/amqp/sasl.py
index 9a98a7a..407ccb8 100644
--- a/amqp/sasl.py
+++ b/amqp/sasl.py
@@ -34,6 +34,11 @@ class PLAIN(SASL):
     def __init__(self, username, password):
         self.username, self.password = username, password
 
+    __slots__ = (
+        "username",
+        "password",
+        )
+
     def start(self, connection):
         if self.username is None or self.password is None:
             return NotImplemented
@@ -56,6 +61,11 @@ class AMQPLAIN(SASL):
     def __init__(self, username, password):
         self.username, self.password = username, password
 
+    __slots__ = (
+        "username",
+        "password",
+        )
+
     def start(self, connection):
         if self.username is None or self.password is None:
             return NotImplemented
@@ -104,6 +114,13 @@ def _get_gssapi_mechanism():
                 self.service = service
                 self.rdns = rdns
 
+            __slots__ = (
+                "client_name",
+                "fail_soft",
+                "service",
+                "rdns"
+                )
+
             def get_hostname(self, connection):
                 sock = connection.transport.sock
                 if self.rdns and sock.family in (socket.AF_INET,
diff --git a/amqp/serialization.py b/amqp/serialization.py
index 90f5857..1f2f8e2 100644
--- a/amqp/serialization.py
+++ b/amqp/serialization.py
@@ -488,6 +488,19 @@ class GenericContent:
         self.body_size = 0
         self.ready = False
 
+    __slots__ = (
+        "frame_method",
+        "frame_args",
+        "properties",
+        "_pending_chunks",
+        "body_received",
+        "body_size",
+        "ready",
+        # adding '__dict__' to get dynamic assignment
+        "__dict__",
+        "__weakref__",
+        )
+
     def __getattr__(self, name):
         # Look for additional properties in the 'properties'
         # dictionary, and if present - the 'delivery_info' dictionary.
diff --git a/amqp/transport.py b/amqp/transport.py
index b87f9fe..b5a0d4b 100644
--- a/amqp/transport.py
+++ b/amqp/transport.py
@@ -97,6 +97,22 @@ class _AbstractTransport:
         self.write_timeout = write_timeout
         self.socket_settings = socket_settings
 
+    __slots__ = (
+        "connection",
+        "sock",
+        "raise_on_initial_eintr",
+        "_read_buffer",
+        "host",
+        "port",
+        "connect_timeout",
+        "read_timeout",
+        "write_timeout",
+        "socket_settings",
+        # adding '__dict__' to get dynamic assignment
+        "__dict__",
+        "__weakref__",
+        )
+
     def __repr__(self):
         if self.sock:
             src = f'{self.sock.getsockname()[0]}:{self.sock.getsockname()[1]}'
@@ -410,6 +426,10 @@ class SSLTransport(_AbstractTransport):
         super().__init__(
             host, connect_timeout=connect_timeout, **kwargs)
 
+    __slots__ = (
+        "sslopts",
+        )
+
     def _setup_transport(self):
         """Wrap the socket in an SSL object."""
         self.sock = self._wrap_socket(self.sock, **self.sslopts)