import logging import select import time import aprslib from aprslib import is_py3 from aprslib.exceptions import ( ConnectionDrop, ConnectionError, GenericError, LoginError, ParseError, UnknownFormat, ) import aprsd from aprsd import stats LOG = logging.getLogger("APRSD") class Client: """Singleton client class that constructs the aprslib connection.""" _instance = None aprs_client = None config = None connected = False server_string = None def __new__(cls, *args, **kwargs): """This magic turns this into a singleton.""" if cls._instance is None: cls._instance = super().__new__(cls) # Put any initialization here. return cls._instance def __init__(self, config=None): """Initialize the object instance.""" if config: self.config = config @property def client(self): if not self.aprs_client: self.aprs_client = self.setup_connection() return self.aprs_client def reset(self): """Call this to force a rebuild/reconnect.""" del self.aprs_client def setup_connection(self): user = self.config["aprs"]["login"] password = self.config["aprs"]["password"] host = self.config["aprs"].get("host", "rotate.aprs.net") port = self.config["aprs"].get("port", 14580) connected = False backoff = 1 while not connected: try: LOG.info("Creating aprslib client") aprs_client = Aprsdis(user, passwd=password, host=host, port=port) # Force the logging to be the same aprs_client.logger = LOG aprs_client.connect() connected = True backoff = 1 except LoginError as e: LOG.error(f"Failed to login to APRS-IS Server '{e}'") connected = False raise e except Exception as e: LOG.error(f"Unable to connect to APRS-IS server. '{e}' ") time.sleep(backoff) backoff = backoff * 2 continue LOG.debug(f"Logging in to APRS-IS with user '{user}'") return aprs_client class Aprsdis(aprslib.IS): """Extend the aprslib class so we can exit properly.""" # flag to tell us to stop thread_stop = False # timeout in seconds select_timeout = 10 def stop(self): self.thread_stop = True LOG.info("Shutdown Aprsdis client.") def _socket_readlines(self, blocking=False): """ Generator for complete lines, received from the server """ try: self.sock.setblocking(0) except OSError as e: self.logger.error(f"socket error when setblocking(0): {str(e)}") raise aprslib.ConnectionDrop("connection dropped") while not self.thread_stop: short_buf = b"" newline = b"\r\n" # set a select timeout, so we get a chance to exit # when user hits CTRL-C readable, writable, exceptional = select.select( [self.sock], [], [], self.select_timeout, ) if not readable: continue try: short_buf = self.sock.recv(4096) # sock.recv returns empty if the connection drops if not short_buf: self.logger.error("socket.recv(): returned empty") raise aprslib.ConnectionDrop("connection dropped") except OSError as e: # self.logger.error("socket error on recv(): %s" % str(e)) if "Resource temporarily unavailable" in str(e): if not blocking: if len(self.buf) == 0: break self.buf += short_buf while newline in self.buf: line, self.buf = self.buf.split(newline, 1) yield line def _send_login(self): """ Sends login string to server """ login_str = "user {0} pass {1} vers github.com/craigerl/aprsd {3}{2}\r\n" login_str = login_str.format( self.callsign, self.passwd, (" filter " + self.filter) if self.filter != "" else "", aprsd.__version__, ) self.logger.info("Sending login information") try: self._sendall(login_str) self.sock.settimeout(5) test = self.sock.recv(len(login_str) + 100) if is_py3: test = test.decode("latin-1") test = test.rstrip() self.logger.debug("Server: %s", test) a, b, callsign, status, e = test.split(" ", 4) s = e.split(",") if len(s): server_string = s[0].replace("server ", "") else: server_string = e.replace("server ", "") self.logger.info(f"Connected to {server_string}") self.server_string = server_string stats.APRSDStats().set_aprsis_server(server_string) if callsign == "": raise LoginError("Server responded with empty callsign???") if callsign != self.callsign: raise LoginError(f"Server: {test}") if status != "verified," and self.passwd != "-1": raise LoginError("Password is incorrect") if self.passwd == "-1": self.logger.info("Login successful (receive only)") else: self.logger.info("Login successful") except LoginError as e: self.logger.error(str(e)) self.close() raise except Exception as e: self.close() self.logger.error(f"Failed to login '{e}'") raise LoginError("Failed to login") def consumer(self, callback, blocking=True, immortal=False, raw=False): """ When a position sentence is received, it will be passed to the callback function blocking: if true (default), runs forever, otherwise will return after one sentence You can still exit the loop, by raising StopIteration in the callback function immortal: When true, consumer will try to reconnect and stop propagation of Parse exceptions if false (default), consumer will return raw: when true, raw packet is passed to callback, otherwise the result from aprs.parse() """ if not self._connected: raise ConnectionError("not connected to a server") line = b"" while True: try: for line in self._socket_readlines(blocking): if line[0:1] != b"#": if raw: callback(line) else: callback(self._parse(line)) else: self.logger.debug("Server: %s", line.decode("utf8")) stats.APRSDStats().set_aprsis_keepalive() except ParseError as exp: self.logger.log( 11, "%s\n Packet: %s", exp, exp.packet, ) except UnknownFormat as exp: self.logger.log( 9, "%s\n Packet: %s", exp, exp.packet, ) except LoginError as exp: self.logger.error("%s: %s", exp.__class__.__name__, exp) except (KeyboardInterrupt, SystemExit): raise except (ConnectionDrop, ConnectionError): self.close() if not immortal: raise else: self.connect(blocking=blocking) continue except GenericError: pass except StopIteration: break except Exception: self.logger.error("APRS Packet: %s", line) raise if not blocking: break def get_client(): cl = Client() return cl.client