Split async_io.py and simplify server start/stop. (#2528)

examples/contrib/serial_forwarder.py

@@ -11,7 +11,7 @@
 from pymodbus.client import ModbusSerialClient
 from pymodbus.datastore import ModbusServerContext
 from pymodbus.datastore.remote import RemoteSlaveContext
-from pymodbus.server.async_io import ModbusTcpServer
+from pymodbus.server import ModbusTcpServer
 
 
 _logger = logging.getLogger(__file__)

examples/server_async.py

@@ -136,18 +136,15 @@ def setup_server(description=None, context=None, cmdline=None):
     return args
 
 
-async def run_async_server(args):
+async def run_async_server(args) -> None:
     """Run server."""
     txt = f"### start ASYNC server, listening on {args.port} - {args.comm}"
     _logger.info(txt)
-    server = None
     if args.comm == "tcp":
         address = (args.host if args.host else "", args.port if args.port else None)
-        server = await StartAsyncTcpServer(
+        await StartAsyncTcpServer(
             context=args.context,  # Data storage
             identity=args.identity,  # server identify
-            # TBD host=
-            # TBD port=
             address=address,  # listen address
             # custom_functions=[],  # allow custom handling
             framer=args.framer,  # The framer strategy to use
@@ -160,7 +157,7 @@ async def run_async_server(args):
             args.host if args.host else "127.0.0.1",
             args.port if args.port else None,
         )
-        server = await StartAsyncUdpServer(
+        await StartAsyncUdpServer(
             context=args.context,  # Data storage
             identity=args.identity,  # server identify
             address=address,  # listen address
@@ -173,7 +170,7 @@ async def run_async_server(args):
     elif args.comm == "serial":
         # socat -d -d PTY,link=/tmp/ptyp0,raw,echo=0,ispeed=9600
         #             PTY,link=/tmp/ttyp0,raw,echo=0,ospeed=9600
-        server = await StartAsyncSerialServer(
+        await StartAsyncSerialServer(
             context=args.context,  # Data storage
             identity=args.identity,  # server identify
             # timeout=1,  # waiting time for request to complete
@@ -190,9 +187,8 @@ async def run_async_server(args):
         )
     elif args.comm == "tls":
         address = (args.host if args.host else "", args.port if args.port else None)
-        server = await StartAsyncTlsServer(
+        await StartAsyncTlsServer(
             context=args.context,  # Data storage
-            host="localhost",  # define tcp address where to connect to.
             # port=port,  # on which port
             identity=args.identity,  # server identify
             # custom_functions=[],  # allow custom handling
@@ -210,10 +206,9 @@ async def run_async_server(args):
             # broadcast_enable=False,  # treat slave 0 as broadcast address,
             # timeout=1,  # waiting time for request to complete
         )
-    return server
 
 
-async def async_helper():
+async def async_helper() -> None:
     """Combine setup and run."""
     _logger.info("Starting...")
     run_args = setup_server(description="Run asynchronous server.")

examples/server_sync.py

@@ -62,18 +62,15 @@
 _logger.setLevel("DEBUG")
 
 
-def run_sync_server(args):
+def run_sync_server(args) -> None:
     """Run server."""
     txt = f"### start SYNC server, listening on {args.port} - {args.comm}"
     _logger.info(txt)
-    server = None
     if args.comm == "tcp":
         address = ("", args.port) if args.port else None
-        server = StartTcpServer(
+        StartTcpServer(
             context=args.context,  # Data storage
             identity=args.identity,  # server identify
-            # TBD host=
-            # TBD port=
             address=address,  # listen address
             # custom_functions=[],  # allow custom handling
             framer=args.framer,  # The framer strategy to use
@@ -83,7 +80,7 @@ def run_sync_server(args):
         )
     elif args.comm == "udp":
         address = ("127.0.0.1", args.port) if args.port else None
-        server = StartUdpServer(
+        StartUdpServer(
             context=args.context,  # Data storage
             identity=args.identity,  # server identify
             address=address,  # listen address
@@ -96,7 +93,7 @@ def run_sync_server(args):
     elif args.comm == "serial":
         # socat -d -d PTY,link=/tmp/ptyp0,raw,echo=0,ispeed=9600
         #             PTY,link=/tmp/ttyp0,raw,echo=0,ospeed=9600
-        server = StartSerialServer(
+        StartSerialServer(
             context=args.context,  # Data storage
             identity=args.identity,  # server identify
             # timeout=1,  # waiting time for request to complete
@@ -113,9 +110,8 @@ def run_sync_server(args):
         )
     elif args.comm == "tls":
         address = ("", args.port) if args.port else None
-        server = StartTlsServer(
+        StartTlsServer(
             context=args.context,  # Data storage
-            host="localhost",  # define tcp address where to connect to.
             # port=port,  # on which port
             identity=args.identity,  # server identify
             # custom_functions=[],  # allow custom handling
@@ -133,14 +129,13 @@ def run_sync_server(args):
             # broadcast_enable=False,  # treat slave 0 as broadcast address,
             # timeout=1,  # waiting time for request to complete
         )
-    return server
 
 
-def sync_helper():
+def sync_helper() -> None:
     """Combine setup and run."""
     run_args = server_async.setup_server(description="Run synchronous server.")
-    server = run_sync_server(run_args)
-    server.shutdown()
+    run_sync_server(run_args)
+    # server.shutdown()
 
 
 if __name__ == "__main__":

pymodbus/server/__init__.py

@@ -22,11 +22,15 @@
     "get_simulator_commandline",
 ]
 
-from pymodbus.server.async_io import (
+from pymodbus.server.server import (
     ModbusSerialServer,
     ModbusTcpServer,
     ModbusTlsServer,
     ModbusUdpServer,
+)
+from pymodbus.server.simulator.http_server import ModbusSimulatorServer
+from pymodbus.server.simulator.main import get_commandline as get_simulator_commandline
+from pymodbus.server.startstop import (
     ServerAsyncStop,
     ServerStop,
     StartAsyncSerialServer,
@@ -38,5 +42,3 @@
     StartTlsServer,
     StartUdpServer,
 )
-from pymodbus.server.simulator.http_server import ModbusSimulatorServer
-from pymodbus.server.simulator.main import get_commandline as get_simulator_commandline