Created simple minimal DUMMY subsystem for testing and development wi…

DUMMY/simulated_dummy.py

@@ -0,0 +1,114 @@
+"""
+This program is a dummy subsystem used with the dummy subsystem handler for development of OBC FSW
+
+It communicates with the dummy subsystem via TCP, by spawning a TCP server and listening for TCP \
+client conn request from dummy handler.
+
+Client commands:
+- EXIT -> command to terminate its connection.
+- QUIT -> command to terminate the server.
+- GET_DUMMY_VAR -> command to get the value of DummyVar.
+- SET_DUMMY_VAR:<VALUE> -> command to set the value of DummyVar to VALUE.
+
+"""
+
+import socket
+import sys
+
+DUMMY_SIM_PORT = 1899
+
+DEFAULT_STATE_VALUES = {
+    'DummyVar': 1,     # Dummy variable
+}
+
+
+class DummySubsystem:
+    """
+    Hold the state of the dummy subsystem
+
+    """
+
+    def __init__(self):
+        # Load default state values
+        self.state = {
+            'DummyVar': DEFAULT_STATE_VALUES['DummyVar'],
+        }
+        self.updatable_parameters = ['']
+
+    # pylint: disable=C0116
+    def set_dummy_var(self, new_value):
+        self.state['DummyVar'] = new_value
+
+    # pylint: disable=C0116
+    def get_dummy_var(self):
+        return self.state['DummyVar']
+
+
+def start_server(hostname, port):
+    """
+    Creates a server socket object with given port and name. client que is 5.
+
+    Args:
+        hostname(string): hostname for server
+        port(int): port bound to server
+
+    Returns:
+        server_socket(socket): server socket object
+    """
+
+    server_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+    server_socket.bind((hostname, port))
+    server_socket.listen(5)
+    return server_socket
+
+
+def handle_read_data(read_data):
+    """
+    Handles the data received from the client
+
+    Args:
+        data(byte): data received from client
+
+    Returns:
+        data(string): data received from client
+    """
+
+    decoded_data = read_data.decode().strip().split(':')
+    command = decoded_data[0]
+    print("Received command:", command)
+    if command == "GET_DUMMY_VAR":
+        print("Returning DummyVar:", Dummy.get_dummy_var())
+        return str(Dummy.get_dummy_var())
+    if command == "SET_DUMMY_VAR":
+        Dummy.set_dummy_var(decoded_data[1])
+        print("DummyVar set to:", decoded_data[1])
+        return "OK"
+    if command == "EXIT":
+        return "EXIT"
+    if command == "QUIT":
+        return "QUIT"
+    print("Invalid command read: " + command)
+    return "ERR"
+
+
+if __name__ == "__main__":
+    Dummy = DummySubsystem()
+    server = start_server('127.0.0.1', DUMMY_SIM_PORT)
+
+    # Continuously listen for incomming data, and respond when request for dummy data is received
+    while True:
+        conn, addr = server.accept()
+        with conn:
+            print("Connected by", addr)
+            while True:
+                data = conn.recv(1024)
+                if not data:
+                    break
+                RES = handle_read_data(data)
+                if RES.strip() == "EXIT":
+                    break
+                if RES.strip() == "QUIT":
+                    sys.exit()
+                else:
+                    RETURN_DATA = str(RES) + "\n"
+                    conn.sendall(RETURN_DATA.encode())