Merge pull request #18 from SCHUNK-SE-Co-KG/modbus-server

Improve modbus server

Author: stefanscherzinger

schunk_gripper_library/tests/conftest.py

@@ -2,6 +2,7 @@
 from schunk_gripper_library.tests.etc.pseudo_terminals import Connection
 from schunk_gripper_library.tests.etc.modbus_server import ModbusServer
 import asyncio
+import threading
 from pathlib import Path
 
 
@@ -20,15 +21,32 @@ def pseudo_terminals():
 @pytest.fixture(scope="module")
 def modbus_server(pseudo_terminals):
     pt1, pt2 = pseudo_terminals
-    server = ModbusServer()
-    print("Opening Modbus server")
-    asyncio.run(server.setup(port=pt1))
-    asyncio.run(server.start())
 
+    async def periodic_modbus_task(pt1, stop_event):
+        server = ModbusServer()
+        await server.setup(port=pt1)
+        await server.start()
+
+        try:
+            while not stop_event.is_set():
+                await asyncio.sleep(1)
+        finally:
+            server.stop()
+
+    loop = asyncio.new_event_loop()
+    thread = threading.Thread(target=lambda: loop.run_forever())
+    thread.start()
+
+    stop_event = asyncio.Event()
+    task = asyncio.run_coroutine_threadsafe(periodic_modbus_task(pt1, stop_event), loop)
     yield pt2
 
-    print("Closing Modbus server")
-    server.stop()
+    stop_event.set()
+    task.result()
+
+    loop.call_soon_threadsafe(loop.stop)
+    thread.join()
+    loop.close()
 
 
 def modbus_gripper_available():

schunk_gripper_library/tests/etc/modbus_server.py

@@ -41,12 +41,11 @@ def trace_connect(self, connect: bool) -> None:
 
     async def setup(self, port: str):
         datablock = ModbusSequentialDataBlock(0x00, [0] * 1000)
-        slave_id = 12  # SCHUNK default
         slave_context = ModbusSlaveContext(
             di=datablock, co=datablock, hr=datablock, ir=datablock
         )
         context = ModbusServerContext(
-            slaves={slave_id: slave_context},
+            slaves=slave_context,
             single=True,
         )
         self.server = ModbusSerialServer(

schunk_gripper_library/tmp/client.py

@@ -1,10 +1,13 @@
 #!/usr/bin/env python3
-from src.driver import Driver
+import sys
+
+sys.path.append("..")
+from src.driver import Driver  # noqa: E402
 
 
 def main():
     driver = Driver()
-    driver.connect("modbus", "/dev/pts/14", 12)
+    driver.connect("modbus", "/dev/pts/17", 12)
     driver.send_plc_output()
 
 

schunk_gripper_library/tmp/server.py

@@ -7,21 +7,33 @@
 import asyncio  # noqa: E402
 
 
-def main():
+async def main():
     connection = Connection()
     pt1, pt2 = connection.open()
     server = ModbusServer()
     print(f"Opening Modbus server on {pt2}")
-    asyncio.run(server.setup(port=pt1))
-    print(f"Using these parameters: {server.get_params()}")
-    asyncio.run(server.start())
 
-    _ = input("Press enter to close")
+    async def start_server():
+        print("Before start")
+        await server.setup(port=pt1)
+        await server.start()
+        print("After start")
+
+    loop = asyncio.get_event_loop()
+    server_task = loop.create_task(start_server())
+
+    try:
+        while True:
+
+            await asyncio.sleep(5)
+    except asyncio.CancelledError:
+        pass
 
     print("Closing Modbus server")
     server.stop()
     connection.close()
+    loop.run_until_complete(server_task)
 
 
 if __name__ == "__main__":
-    main()
+    asyncio.run(main())