move tcp server into own class and reverted hk handling back to functions from class

pus_tm/tm_tcp_server.py

@@ -0,0 +1,102 @@
+import socket
+from typing import Optional
+import json
+import base64
+
+from tmtccmd.logging import get_console_logger
+from tmtccmd.utility.obj_id import ObjectId
+
+
+# TODO add to configuration parameters
+SERVER_HOST = ""
+SERVER_PORT = 7305
+
+LOGGER = get_console_logger()
+
+
+class TmTcpServer:
+
+    _Instance = None
+
+    def __init__(
+            self):
+
+        self.server_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+
+        self.server_socket.bind((SERVER_HOST, SERVER_PORT))
+
+        # for now, only accept one connection
+        self.server_socket.listen(0)
+
+        self.server_socket.setblocking(False)
+
+        self.client_connection: Optional[socket.socket] = None
+
+    def __del__(self):
+        try:
+            self.close()
+        except:
+            LOGGER.warning("Could not close sockets!")
+
+    def close(self):
+        self.server_socket.close()
+        if self.client_connection != None:
+            self.client_connection.close()
+
+    def getInstance():
+        if TmTcpServer._Instance == None:
+            TmTcpServer._Instance = TmTcpServer()
+        return TmTcpServer._Instance
+
+    def _send_dictionary_over_socket(self, dictionary):
+        # keep listeners current
+        if self.client_connection == None:
+            # no running connection, see if a client wants to connect
+            try:
+                (self.client_connection, _) = self.server_socket.accept()
+                self.client_connection.setblocking(False)
+            except:
+                # no client waiting
+                return
+
+        data_json_bytes = json.dumps(dictionary).encode()
+
+        # dle encode the bytes
+        # Taking a shortcut as json is inherently
+        # not binary (we also encoded it as utf-8), so there
+        # can not be any 0x02 or 0x03 be in there
+        data_json_bytes = b'\x02' + data_json_bytes + b'\n' + b'\x03'
+
+        try:
+            sent_length = self.client_connection.send(data_json_bytes)
+        except:
+            self.client_connection = None
+            return
+        if sent_length == 0:
+            self.client_connection.close()
+            self.client_connection = None
+
+    def report_raw_hk_data(self, object_id: ObjectId,
+                    set_id: int,
+                    hk_data: bytes):
+
+        data_dict = {}
+        data_dict["type"] = "TM"
+        data_dict["tmType"] = "Raw HK"
+        data_dict["objectId"] = object_id.as_string
+        data_dict["setId"] = set_id
+        data_dict["rawData"] = base64.b64encode(hk_data).decode()
+
+        self._send_dictionary_over_socket(data_dict)
+
+    def report_parsed_hk_data(self, object_id: ObjectId,
+                set_id: int,
+                data_dictionary):
+        data_dict = {}
+        data_dict["type"] = "TM"
+        data_dict["tmType"] = "Parsed HK"
+        data_dict["objectId"] = object_id.as_string
+        data_dict["setId"] = set_id
+        data_dict["content"] = data_dictionary
+
+        self._send_dictionary_over_socket(data_dict)