Create ClientApp fn example

examples/app-pytorch/client.py

@@ -20,8 +20,6 @@
 
 # Define Flower client
 class FlowerClient(fl.client.NumPyClient):
-    def get_parameters(self, config: Dict[str, Scalar]) -> NDArrays:
-        return get_parameters(net)
 
     def fit(self, parameters, config):
         set_parameters(net, parameters)
@@ -42,3 +40,11 @@ def client_fn(cid: str):
 app = fl.client.ClientApp(
     client_fn=client_fn,
 )
+
+
+# Legacy mode
+if __name__ == "__main__":
+    fl.client.start_client(
+        server_address="127.0.0.1:8080",
+        client=FlowerClient().to_client(),
+    )

examples/app-pytorch/client_low_level.py

@@ -0,0 +1,35 @@
+import flwr
+from flwr.common import Message, Context
+
+
+def hello_world_mod(msg, ctx, call_next) -> Message:
+    print("Hello, ...[pause for dramatic effect]...")
+    out = call_next(msg, ctx)
+    print("...[pause was long enough]... World!")
+    return out
+
+
+# Run via `flower-client-app client:app`
+app = flwr.client.ClientApp(
+    mods=[
+        hello_world_mod,
+    ],
+)
+
+
+@app.train()
+def train(msg: Message, ctx: Context):
+    print("`train` is not implemented, echoing original message")
+    return msg.create_reply(msg.content, ttl="")
+
+
+@app.evaluate()
+def eval(msg: Message, ctx: Context):
+    print("`evaluate` is not implemented, echoing original message")
+    return msg.create_reply(msg.content, ttl="")
+
+
+@app.query()
+def query(msg: Message, ctx: Context):
+    print("`query` is not implemented, echoing original message")
+    return msg.create_reply(msg.content, ttl="")

examples/app-pytorch/server.py

@@ -1,7 +1,8 @@
 from typing import List, Tuple
 
 import flwr as fl
-from flwr.common import Metrics
+from flwr.common import Metrics, ndarrays_to_parameters
+from task import Net, get_parameters
 
 
 # Define metric aggregation function
@@ -25,17 +26,36 @@ def weighted_average(metrics: List[Tuple[int, Metrics]]) -> Metrics:
     }
 
 
+# Initialize model parameters
+ndarrays = get_parameters(Net())
+parameters = ndarrays_to_parameters(ndarrays)
+
+
 # Define strategy
 strategy = fl.server.strategy.FedAvg(
     fraction_fit=1.0,  # Select all available clients
     fraction_evaluate=0.0,  # Disable evaluation
     min_available_clients=2,
     fit_metrics_aggregation_fn=weighted_average,
+    initial_parameters=parameters,
 )
 
 
+# Define config
+config = fl.server.ServerConfig(num_rounds=3)
+
+
 # Run via `flower-server-app server:app`
 app = fl.server.ServerApp(
-    config=fl.server.ServerConfig(num_rounds=3),
+    config=config,
     strategy=strategy,
 )
+
+
+# Legacy mode
+if __name__ == "__main__":
+    fl.server.start_server(
+        server_address="0.0.0.0:8080",
+        config=config,
+        strategy=strategy,
+    )

examples/app-pytorch/server_low_level.py

@@ -0,0 +1,52 @@
+from typing import List, Tuple, Dict
+import random
+import time
+
+import flwr as fl
+from flwr.common import Context, NDArrays, Message, MessageType, Metrics, RecordSet
+from flwr.server import Driver
+
+
+# Run via `flower-server-app server:app`
+app = fl.server.ServerApp()
+
+
+@app.main()
+def main(driver: Driver, context: Context) -> None:
+    """This is a stub example that simply sends and receives messages."""
+    print("Starting test run")
+    for server_round in range(3):
+        print(f"Commencing server round {server_round + 1}")
+
+        # Get node IDs
+        node_ids = driver.get_node_ids()
+
+        # Create messages
+        recordset = RecordSet()
+        messages = []
+        for node_id in node_ids:
+            message = driver.create_message(
+                content=recordset,
+                message_type=MessageType.TRAIN,
+                dst_node_id=node_id,
+                group_id=str(server_round),
+                ttl="",
+            )
+            messages.append(message)
+
+        # Send messages
+        message_ids = driver.push_messages(messages)
+        print(f"Pushed {len(message_ids)} messages: {message_ids}")
+
+        # Wait for results, ignore empty message_ids
+        message_ids = [message_id for message_id in message_ids if message_id != ""]
+        all_replies: List[Message] = []
+        while True:
+            replies = driver.pull_messages(message_ids=message_ids)
+            print(f"Got {len(replies)} results")
+            all_replies += replies
+            if len(all_replies) == len(message_ids):
+                break
+            time.sleep(3)
+
+        print(f"Received {len(all_replies)} results")