Rename some gRPC components to improve consistency

src/py/flwr/server/grpc_server/flower_service_servicer.py

@@ -15,8 +15,10 @@
 """Servicer for FlowerService.
 
 Relevant knowledge for reading this modules code:
-    - https://github.com/grpc/grpc/blob/master/doc/statuscodes.md
+- https://github.com/grpc/grpc/blob/master/doc/statuscodes.md
 """
+
+
 from typing import Callable, Iterator
 
 import grpc
@@ -25,36 +27,34 @@
 from flwr.proto import transport_pb2_grpc
 from flwr.proto.transport_pb2 import ClientMessage, ServerMessage
 from flwr.server.client_manager import ClientManager
-from flwr.server.grpc_server.grpc_bridge import GRPCBridge, InsWrapper, ResWrapper
+from flwr.server.grpc_server.grpc_bridge import GrpcBridge, InsWrapper, ResWrapper
 from flwr.server.grpc_server.grpc_client_proxy import GrpcClientProxy
 
 
-def default_bridge_factory() -> GRPCBridge:
-    """Return GRPCBridge instance."""
-    return GRPCBridge()
+def default_bridge_factory() -> GrpcBridge:
+    """Return GrpcBridge instance."""
+    return GrpcBridge()
 
 
-def default_grpc_client_factory(cid: str, bridge: GRPCBridge) -> GrpcClientProxy:
+def default_grpc_client_proxy_factory(cid: str, bridge: GrpcBridge) -> GrpcClientProxy:
     """Return GrpcClientProxy instance."""
     return GrpcClientProxy(cid=cid, bridge=bridge)
 
 
-def register_client(
+def register_client_proxy(
     client_manager: ClientManager,
-    client: GrpcClientProxy,
+    client_proxy: GrpcClientProxy,
     context: grpc.ServicerContext,
 ) -> bool:
     """Try registering GrpcClientProxy with ClientManager."""
-    is_success = client_manager.register(client)
-
+    is_success = client_manager.register(client_proxy)
     if is_success:
 
         def rpc_termination_callback() -> None:
-            client.bridge.close()
-            client_manager.unregister(client)
+            client_proxy.bridge.close()
+            client_manager.unregister(client_proxy)
 
         context.add_callback(rpc_termination_callback)
-
     return is_success
 
 
@@ -64,33 +64,32 @@ class FlowerServiceServicer(transport_pb2_grpc.FlowerServiceServicer):
     def __init__(
         self,
         client_manager: ClientManager,
-        grpc_bridge_factory: Callable[[], GRPCBridge] = default_bridge_factory,
-        grpc_client_factory: Callable[
-            [str, GRPCBridge], GrpcClientProxy
-        ] = default_grpc_client_factory,
+        grpc_bridge_factory: Callable[[], GrpcBridge] = default_bridge_factory,
+        grpc_client_proxy_factory: Callable[
+            [str, GrpcBridge], GrpcClientProxy
+        ] = default_grpc_client_proxy_factory,
     ) -> None:
         self.client_manager: ClientManager = client_manager
         self.grpc_bridge_factory = grpc_bridge_factory
-        self.client_factory = grpc_client_factory
+        self.client_proxy_factory = grpc_client_proxy_factory
 
     def Join(  # pylint: disable=invalid-name
         self,
         request_iterator: Iterator[ClientMessage],
         context: grpc.ServicerContext,
     ) -> Iterator[ServerMessage]:
-        """Method will be invoked by each GrpcClientProxy which participates in
-        the network.
+        """Invoked by each gRPC client which participates in the network.
 
         Protocol:
-            - The first message is sent from the server to the client
-            - Both ServerMessage and ClientMessage are message "wrappers"
-                wrapping the actual message
-            - The Join method is (pretty much) protocol unaware
+        - The first message is sent from the server to the client
+        - Both `ServerMessage` and `ClientMessage` are message "wrappers"
+          wrapping the actual message
+        - The `Join` method is (pretty much) unaware of the protocol
         """
         peer: str = context.peer()
         bridge = self.grpc_bridge_factory()
-        client = self.client_factory(peer, bridge)
-        is_success = register_client(self.client_manager, client, context)
+        client_proxy = self.client_proxy_factory(peer, bridge)
+        is_success = register_client_proxy(self.client_manager, client_proxy, context)
 
         if is_success:
             # Get iterators

src/py/flwr/server/grpc_server/flower_service_servicer_test.py

@@ -13,13 +13,15 @@
 # limitations under the License.
 # ==============================================================================
 """Tests for FlowerServiceServicer."""
+
+
 import unittest
 from unittest.mock import MagicMock, call
 
 from flwr.proto.transport_pb2 import ClientMessage, ServerMessage
 from flwr.server.grpc_server.flower_service_servicer import (
     FlowerServiceServicer,
-    register_client,
+    register_client_proxy,
 )
 from flwr.server.grpc_server.grpc_bridge import InsWrapper, ResWrapper
 
@@ -53,7 +55,7 @@ def setUp(self) -> None:
         ]
         self.ins_wrapper_iterator = iter(self.ins_wrappers)
 
-        # Mock for GRPCBridge
+        # Mock for GrpcBridge
         self.grpc_bridge_mock = MagicMock()
         self.grpc_bridge_mock.ins_wrapper_iterator.return_value = (
             self.ins_wrapper_iterator
@@ -67,20 +69,20 @@ def setUp(self) -> None:
         self.grpc_client_proxy_mock = MagicMock()
         self.grpc_client_proxy_mock.cid = CLIENT_CID
 
-        self.client_factory_mock = MagicMock()
-        self.client_factory_mock.return_value = self.grpc_client_proxy_mock
+        self.client_proxy_factory_mock = MagicMock()
+        self.client_proxy_factory_mock.return_value = self.grpc_client_proxy_mock
 
         self.client_manager_mock = MagicMock()
 
-    def test_register_client(self) -> None:
-        """Test register_client function."""
+    def test_register_client_proxy(self) -> None:
+        """Test register_client_proxy function."""
         # Prepare
         self.client_manager_mock.register.return_value = True
 
         # Execute
-        register_client(
+        register_client_proxy(
             client_manager=self.client_manager_mock,
-            client=self.grpc_client_proxy_mock,
+            client_proxy=self.grpc_client_proxy_mock,
             context=self.context_mock,
         )
 
@@ -107,7 +109,7 @@ def test_join(self) -> None:
         servicer = FlowerServiceServicer(
             client_manager=self.client_manager_mock,
             grpc_bridge_factory=self.grpc_bridge_factory_mock,
-            grpc_client_factory=self.client_factory_mock,
+            grpc_client_proxy_factory=self.client_proxy_factory_mock,
         )
 
         # Execute
@@ -124,7 +126,7 @@ def test_join(self) -> None:
         assert len(self.client_messages) == num_server_messages
         assert self.grpc_client_proxy_mock.cid == CLIENT_CID
 
-        self.client_factory_mock.assert_called_once_with(
+        self.client_proxy_factory_mock.assert_called_once_with(
             CLIENT_CID, self.grpc_bridge_mock
         )
 

src/py/flwr/server/grpc_server/grpc_bridge.py

@@ -12,7 +12,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 # ==============================================================================
-"""Provides class GRPCBridge."""
+"""Provides class GrpcBridge."""
+
 
 from dataclasses import dataclass
 from enum import Enum
@@ -37,8 +38,8 @@ class ResWrapper:
     client_message: ClientMessage
 
 
-class GRPCBridgeClosed(Exception):
-    """Error signaling that GRPCBridge is closed."""
+class GrpcBridgeClosed(Exception):
+    """Error signaling that GrpcBridge is closed."""
 
 
 class Status(Enum):
@@ -51,8 +52,8 @@ class Status(Enum):
     CLOSED = 5
 
 
-class GRPCBridge:
-    """GRPCBridge holding res_wrapper and ins_wrapper.
+class GrpcBridge:
+    """GrpcBridge holding res_wrapper and ins_wrapper.
 
     For understanding this class it is recommended to understand how
     the threading.Condition class works. See here:
@@ -74,7 +75,7 @@ def _is_closed(self) -> bool:
 
     def _raise_if_closed(self) -> None:
         if self._status == Status.CLOSED:
-            raise GRPCBridgeClosed()
+            raise GrpcBridgeClosed()
 
     def _transition(self, next_status: Status) -> None:
         """Validate status transition and set next status.

src/py/flwr/server/grpc_server/grpc_bridge_test.py

@@ -12,7 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 # ==============================================================================
-"""Tests for GRPCBridge class."""
+"""Tests for GrpcBridge class."""
 
 
 import time
@@ -21,15 +21,15 @@
 
 from flwr.proto.transport_pb2 import ClientMessage, ServerMessage
 from flwr.server.grpc_server.grpc_bridge import (
-    GRPCBridge,
-    GRPCBridgeClosed,
+    GrpcBridge,
+    GrpcBridgeClosed,
     InsWrapper,
     ResWrapper,
 )
 
 
 def start_worker(
-    rounds: int, bridge: GRPCBridge, results: List[ClientMessage]
+    rounds: int, bridge: GrpcBridge, results: List[ClientMessage]
 ) -> Thread:
     """Simulate processing loop with five calls."""
 
@@ -41,7 +41,7 @@ def _worker() -> None:
                 res_wrapper = bridge.request(
                     InsWrapper(server_message=ServerMessage(), timeout=None)
                 )
-            except GRPCBridgeClosed:
+            except GrpcBridgeClosed:
                 break
 
             results.append(res_wrapper.client_message)
@@ -58,7 +58,7 @@ def test_workflow_successful() -> None:
     rounds = 5
     client_messages_received: List[ClientMessage] = []
 
-    bridge = GRPCBridge()
+    bridge = GrpcBridge()
     ins_wrapper_iterator = bridge.ins_wrapper_iterator()
 
     worker_thread = start_worker(rounds, bridge, client_messages_received)
@@ -88,12 +88,12 @@ def test_workflow_close() -> None:
     rounds = 5
     client_messages_received: List[ClientMessage] = []
 
-    bridge = GRPCBridge()
+    bridge = GrpcBridge()
     ins_wrapper_iterator = bridge.ins_wrapper_iterator()
 
     worker_thread = start_worker(rounds, bridge, client_messages_received)
 
-    raised_error: Union[GRPCBridgeClosed, StopIteration, None] = None
+    raised_error: Union[GrpcBridgeClosed, StopIteration, None] = None
 
     # Execute
     for i in range(rounds):
@@ -109,7 +109,7 @@ def test_workflow_close() -> None:
                 # on next invocation.
                 bridge.close()
 
-        except GRPCBridgeClosed as err:
+        except GrpcBridgeClosed as err:
             raised_error = err
             break
         except StopIteration as err:
@@ -133,12 +133,12 @@ def test_ins_wrapper_iterator_close_while_blocking() -> None:
     rounds = 5
     client_messages_received: List[ClientMessage] = []
 
-    bridge = GRPCBridge()
+    bridge = GrpcBridge()
     ins_wrapper_iterator = bridge.ins_wrapper_iterator()
 
     worker_thread = start_worker(rounds, bridge, client_messages_received)
 
-    raised_error: Union[GRPCBridgeClosed, StopIteration, None] = None
+    raised_error: Union[GrpcBridgeClosed, StopIteration, None] = None
 
     def close_bridge_delayed(secs: int) -> None:
         """Close brige after {secs} second(s)."""
@@ -160,7 +160,7 @@ def close_bridge_delayed(secs: int) -> None:
             if i < 2:
                 bridge.set_res_wrapper(ResWrapper(ClientMessage()))
 
-        except GRPCBridgeClosed as err:
+        except GrpcBridgeClosed as err:
             raised_error = err
             break
         except StopIteration as err:
@@ -172,4 +172,4 @@ def close_bridge_delayed(secs: int) -> None:
 
     # Assert
     assert len(client_messages_received) == 2
-    assert isinstance(raised_error, GRPCBridgeClosed)
+    assert isinstance(raised_error, GrpcBridgeClosed)

src/py/flwr/server/grpc_server/grpc_client_proxy.py

@@ -14,22 +14,23 @@
 # ==============================================================================
 """gRPC-based Flower ClientProxy implementation."""
 
+
 from typing import Optional
 
 from flwr import common
 from flwr.common import serde
 from flwr.proto.transport_pb2 import ClientMessage, ServerMessage
 from flwr.server.client_proxy import ClientProxy
-from flwr.server.grpc_server.grpc_bridge import GRPCBridge, InsWrapper, ResWrapper
+from flwr.server.grpc_server.grpc_bridge import GrpcBridge, InsWrapper, ResWrapper
 
 
 class GrpcClientProxy(ClientProxy):
-    """Flower client proxy which delegates over the network using gRPC."""
+    """Flower ClientProxy that uses gRPC to delegate tasks over the network."""
 
     def __init__(
         self,
         cid: str,
-        bridge: GRPCBridge,
+        bridge: GrpcBridge,
     ):
         super().__init__(cid)
         self.bridge = bridge