eive-tmtc/pus_tm/tm_tcp_server.py

import socket
from typing import Optional
import json
import base64

from tmtccmd.logging import get_console_logger
from tmtccmd.utility.obj_id import ObjectId
from dle_encoder import DleEncoder

# 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

        self.dle_encoder = DleEncoder()

    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
        # adding a newline because someone might want to look at it in a console
        data_json_bytes = self.dle_encoder.encode(data_json_bytes + b'\n')

        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)