Let us start here, from square one. No, from Zero!

api/resources/python/spiceapi/connection.py

@@ -0,0 +1,139 @@
+import os
+import socket
+from .request import Request
+from .response import Response
+from .rc4 import rc4
+from .exceptions import MalformedRequestException, APIError
+
+
+class Connection:
+    """ Container for managing a single connection to the API server.
+    """
+
+    def __init__(self, host: str, port: int, password: str):
+        """Default constructor.
+
+        :param host: the host string to connect to
+        :param port: the port of the host
+        :param password: the connection password string
+        """
+        self.host = host
+        self.port = port
+        self.password = password
+        self.socket = None
+        self.cipher = None
+        self.reconnect()
+
+    def reconnect(self, refresh_session=True):
+        """Reconnect to the server.
+
+        This opens a new connection and closes the previous one, if existing.
+        """
+
+        # close old socket
+        self.close()
+
+        # create new socket
+        self.socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+        self.socket.settimeout(3)
+        self.socket.setsockopt(socket.IPPROTO_TCP, socket.TCP_NODELAY, 1)
+        self.socket.connect((self.host, self.port))
+
+        # cipher
+        self.change_password(self.password)
+
+        # refresh session
+        if refresh_session:
+            from .control import control_session_refresh
+            control_session_refresh(self)
+
+    def change_password(self, password):
+        """Allows to change the password on the fly.
+
+        The cipher will be rebuilt.
+        """
+        if len(password) > 0:
+            self.cipher = rc4(password.encode("UTF-8"))
+        else:
+            self.cipher = None
+
+    def close(self):
+        """Close the active connection, if existing."""
+
+        # check if socket is existing
+        if self.socket:
+
+            # close and delete socket
+            self.socket.close()
+            self.socket = None
+
+    def request(self, request: Request):
+        """Send a request to the server and receive the answer.
+
+        :param request: request object
+        :return: response object
+        """
+
+        # check if disconnected
+        if not self.socket:
+            raise RuntimeError("No active connection.")
+
+        # build data
+        data = request.to_json().encode("UTF-8") + b"\x00"
+        if self.cipher:
+            data_list = list(data)
+            data_cipher = []
+            for b in data_list:
+                data_cipher.append(b ^ next(self.cipher))
+            data = bytes(data_cipher)
+
+        # send request
+        if os.name != 'nt':
+            self.socket.setsockopt(socket.IPPROTO_TCP, socket.TCP_QUICKACK, 1)
+        self.socket.send(data)
+
+        # get answer
+        answer_data = []
+        while not len(answer_data) or answer_data[-1] != 0:
+
+            # receive data
+            if os.name != 'nt':
+                self.socket.setsockopt(socket.IPPROTO_TCP, socket.TCP_QUICKACK, 1)
+            receive_data = self.socket.recv(4096)
+
+            # check length
+            if len(receive_data):
+
+                # check cipher
+                if self.cipher:
+
+                    # add decrypted data
+                    for b in receive_data:
+                        answer_data.append(int(b ^ next(self.cipher)))
+                else:
+
+                    # add plaintext
+                    for b in receive_data:
+                        answer_data.append(int(b))
+            else:
+                raise RuntimeError("Connection was closed.")
+
+        # check for empty response
+        if len(answer_data) <= 1:
+
+            # empty response means the JSON couldn't be parsed
+            raise MalformedRequestException()
+
+        # build response
+        response = Response(bytes(answer_data[:-1]).decode("UTF-8"))
+        if len(response.get_errors()):
+            raise APIError(response.get_errors())
+
+        # check ID
+        req_id = request.get_id()
+        res_id = response.get_id()
+        if req_id != res_id:
+            raise RuntimeError(f"Unexpected response ID: {res_id} (expected {req_id})")
+
+        # return response object
+        return response