""" # an API for Meshtastic devices Primary class: StreamInterface Install with pip: "[pip3 install meshtastic](https://pypi.org/project/meshtastic/)" Source code on [github](https://github.com/meshtastic/Meshtastic-python) properties of StreamInterface: - radioConfig - Current radio configuration and device settings, if you write to this the new settings will be applied to the device. - nodes - The database of received nodes. Includes always up-to-date location and username information for each node in the mesh. This is a read-only datastructure. - myNodeInfo - Contains read-only information about the local radio device (software version, hardware version, etc) # Published PubSub topics We use a [publish-subscribe](https://pypubsub.readthedocs.io/en/v4.0.3/) model to communicate asynchronous events. Available topics: - meshtastic.connection.established - published once we've successfully connected to the radio and downloaded the node DB - meshtastic.connection.lost - published once we've lost our link to the radio - meshtastic.receive.position(packet) - delivers a received packet as a dictionary, if you only care about a particular type of packet, you should subscribe to the full topic name. If you want to see all packets, simply subscribe to "meshtastic.receive". - meshtastic.receive.user(packet) - meshtastic.receive.data(packet) - meshtastic.node.updated(node = NodeInfo) - published when a node in the DB changes (appears, location changed, username changed, etc...) # Example Usage ``` import meshtastic from pubsub import pub def onReceive(packet, interface): # called when a packet arrives print(f"Received: {packet}") def onConnection(interface, topic=pub.AUTO_TOPIC): # called when we (re)connect to the radio # defaults to broadcast, specify a destination ID if you wish interface.sendText("hello mesh") pub.subscribe(onReceive, "meshtastic.receive") pub.subscribe(onConnection, "meshtastic.connection.established") # By default will try to find a meshtastic device, otherwise provide a device path like /dev/ttyUSB0 interface = meshtastic.StreamInterface() ``` """ import pygatt import google.protobuf.json_format import serial import threading import logging import time import sys import traceback import time from . import mesh_pb2 from . import util from pubsub import pub from dotmap import DotMap START1 = 0x94 START2 = 0xc3 HEADER_LEN = 4 MAX_TO_FROM_RADIO_SIZE = 512 BROADCAST_ADDR = "^all" # A special ID that means broadcast # if using 8 bit nodenums this will be shortend on the target BROADCAST_NUM = 0xffffffff MY_CONFIG_ID = 42 """The numeric buildnumber (shared with android apps) specifying the level of device code we are guaranteed to understand""" OUR_APP_VERSION = 172 class MeshInterface: """Interface class for meshtastic devices Properties: isConnected nodes debugOut """ def __init__(self, debugOut=None, noProto=False): """Constructor""" self.debugOut = debugOut self.nodes = None # FIXME self.isConnected = False if not noProto: self._startConfig() def sendText(self, text, destinationId=BROADCAST_ADDR, wantAck=False, wantResponse=False): """Send a utf8 string to some other node, if the node has a display it will also be shown on the device. Arguments: text {string} -- The text to send Keyword Arguments: destinationId {nodeId or nodeNum} -- where to send this message (default: {BROADCAST_ADDR}) wantAck -- True if you want the message sent in a reliable manner (with retries and ack/nak provided for delivery) Returns the sent packet. The id field will be populated in this packet and can be used to track future message acks/naks. """ return self.sendData(text.encode("utf-8"), destinationId, dataType=mesh_pb2.Data.CLEAR_TEXT, wantAck=wantAck, wantResponse=wantResponse) def sendData(self, byteData, destinationId=BROADCAST_ADDR, dataType=mesh_pb2.Data.OPAQUE, wantAck=False, wantResponse=False): """Send a data packet to some other node Keyword Arguments: destinationId {nodeId or nodeNum} -- where to send this message (default: {BROADCAST_ADDR}) wantAck -- True if you want the message sent in a reliable manner (with retries and ack/nak provided for delivery) Returns the sent packet. The id field will be populated in this packet and can be used to track future message acks/naks. """ meshPacket = mesh_pb2.MeshPacket() meshPacket.decoded.data.payload = byteData meshPacket.decoded.data.typ = dataType meshPacket.decoded.want_response = wantResponse return self.sendPacket(meshPacket, destinationId, wantAck=wantAck) def sendPosition(self, latitude=0.0, longitude=0.0, altitude=0, timeSec=0, destinationId=BROADCAST_ADDR, wantAck=False, wantResponse=False): """ Send a position packet to some other node (normally a broadcast) Also, the device software will notice this packet and use it to automatically set its notion of the local position. If timeSec is not specified (recommended), we will use the local machine time. Returns the sent packet. The id field will be populated in this packet and can be used to track future message acks/naks. """ meshPacket = mesh_pb2.MeshPacket() if(latitude != 0.0): meshPacket.decoded.position.latitude_i = int(latitude / 1e-7) if(longitude != 0.0): meshPacket.decoded.position.longitude_i = int(longitude / 1e-7) if(altitude != 0): meshPacket.decoded.position.altitude = int(altitude) if timeSec == 0: timeSec = time.time() # returns unix timestamp in seconds meshPacket.decoded.position.time = int(timeSec) meshPacket.decoded.want_response = wantResponse return self.sendPacket(meshPacket, destinationId, wantAck=wantAck) def sendPacket(self, meshPacket, destinationId=BROADCAST_ADDR, wantAck=False): """Send a MeshPacket to the specified node (or if unspecified, broadcast). You probably don't want this - use sendData instead. Returns the sent packet. The id field will be populated in this packet and can be used to track future message acks/naks. """ toRadio = mesh_pb2.ToRadio() # FIXME add support for non broadcast addresses if isinstance(destinationId, int): nodeNum = destinationId elif destinationId == BROADCAST_ADDR: nodeNum = BROADCAST_NUM else: nodeNum = self.nodes[destinationId]['num'] meshPacket.to = nodeNum meshPacket.want_ack = wantAck # if the user hasn't set an ID for this packet (likely and recommended), we should pick a new unique ID # so the message can be tracked. if meshPacket.id == 0: meshPacket.id = self._generatePacketId() toRadio.packet.CopyFrom(meshPacket) self._sendToRadio(toRadio) return meshPacket def writeConfig(self): """Write the current (edited) radioConfig to the device""" if self.radioConfig == None: raise Exception("No RadioConfig has been read") t = mesh_pb2.ToRadio() t.set_radio.CopyFrom(self.radioConfig) self._sendToRadio(t) def _generatePacketId(self): """Get a new unique packet ID""" if self.currentPacketId is None: raise Exception("Not connected yet, can not generate packet") else: self.currentPacketId = (self.currentPacketId + 1) & 0xffffffff return self.currentPacketId def _disconnected(self): """Called by subclasses to tell clients this interface has disconnected""" self.isConnected = False pub.sendMessage("meshtastic.connection.lost", interface=self) def _connected(self): """Called by this class to tell clients we are now fully connected to a node """ self.isConnected = True pub.sendMessage("meshtastic.connection.established", interface=self) def _startConfig(self): """Start device packets flowing""" self.myInfo = None self.nodes = {} # nodes keyed by ID self._nodesByNum = {} # nodes keyed by nodenum self.radioConfig = None self.currentPacketId = None startConfig = mesh_pb2.ToRadio() startConfig.want_config_id = MY_CONFIG_ID # we don't use this value self._sendToRadio(startConfig) def _sendToRadio(self, toRadio): """Send a ToRadio protobuf to the device""" logging.error(f"Subclass must provide toradio: {toRadio}") def _handleFromRadio(self, fromRadioBytes): """ Handle a packet that arrived from the radio(update model and publish events) Called by subclasses.""" fromRadio = mesh_pb2.FromRadio() fromRadio.ParseFromString(fromRadioBytes) asDict = google.protobuf.json_format.MessageToDict(fromRadio) logging.debug(f"Received: {asDict}") if fromRadio.HasField("my_info"): self.myInfo = fromRadio.my_info if self.myInfo.min_app_version > OUR_APP_VERSION: raise Exception( "This device needs a newer python client, please \"pip install --upgrade meshtastic\"") # start assigning our packet IDs from the opposite side of where our local device is assigning them self.currentPacketId = ( self.myInfo.current_packet_id + 0x80000000) & 0xffffffff elif fromRadio.HasField("radio"): self.radioConfig = fromRadio.radio elif fromRadio.HasField("node_info"): node = asDict["nodeInfo"] try: self._fixupPosition(node["position"]) except: logging.debug("Node without position") self._nodesByNum[node["num"]] = node if "user" in node: # Some nodes might not have user/ids assigned yet self.nodes[node["user"]["id"]] = node elif fromRadio.config_complete_id == MY_CONFIG_ID: # we ignore the config_complete_id, it is unneeded for our stream API fromRadio.config_complete_id self._connected() elif fromRadio.HasField("packet"): self._handlePacketFromRadio(fromRadio.packet) elif fromRadio.rebooted: self._disconnected() self._startConfig() # redownload the node db etc... else: logging.warn("Unexpected FromRadio payload") def _fixupPosition(self, position): """Convert integer lat/lon into floats Arguments: position {Position dictionary} -- object ot fix up """ if "latitudeI" in position: position["latitude"] = position["latitudeI"] * 1e-7 if "longitudeI" in position: position["longitude"] = position["longitudeI"] * 1e-7 def _nodeNumToId(self, num): """Map a node node number to a node ID Arguments: num {int} -- Node number Returns: string -- Node ID """ if num == BROADCAST_NUM: return BROADCAST_ADDR try: return self._nodesByNum[num]["user"]["id"] except: logging.warn("Node not found for fromId") return None def _getOrCreateByNum(self, nodeNum): """Given a nodenum find the NodeInfo in the DB (or create if necessary)""" if nodeNum == BROADCAST_NUM: raise Exception("Can not create/find nodenum by the broadcast num") if nodeNum in self._nodesByNum: return self._nodesByNum[nodeNum] else: n = {"num": nodeNum} # Create a minimial node db entry self._nodesByNum[nodeNum] = n return n def _handlePacketFromRadio(self, meshPacket): """Handle a MeshPacket that just arrived from the radio Will publish one of the following events: - meshtastic.receive.position(packet = MeshPacket dictionary) - meshtastic.receive.user(packet = MeshPacket dictionary) - meshtastic.receive.data(packet = MeshPacket dictionary) """ asDict = google.protobuf.json_format.MessageToDict(meshPacket) # /add fromId and toId fields based on the node ID asDict["fromId"] = self._nodeNumToId(asDict["from"]) asDict["toId"] = self._nodeNumToId(asDict["to"]) # We could provide our objects as DotMaps - which work with . notation or as dictionaries # asObj = DotMap(asDict) topic = "meshtastic.receive" # Generic unknown packet type if meshPacket.decoded.HasField("position"): topic = "meshtastic.receive.position" p = asDict["decoded"]["position"] self._fixupPosition(p) # update node DB as needed self._getOrCreateByNum(asDict["from"])["position"] = p if meshPacket.decoded.HasField("user"): topic = "meshtastic.receive.user" u = asDict["decoded"]["user"] # update node DB as needed n = self._getOrCreateByNum(asDict["from"]) n["user"] = u # We now have a node ID, make sure it is uptodate in that table self.nodes[u["id"]] = u if meshPacket.decoded.HasField("data"): topic = "meshtastic.receive.data" # OPAQUE is the default protobuf typ value, and therefore if not set it will not be populated at all # to make API usage easier, set it to prevent confusion if not "typ" in asDict["decoded"]["data"]: asDict["decoded"]["data"]["typ"] = "OPAQUE" # For text messages, we go ahead and decode the text to ascii for our users if asDict["decoded"]["data"]["typ"] == "CLEAR_TEXT": asDict["decoded"]["data"]["text"] = meshPacket.decoded.data.payload.decode( "utf-8") pub.sendMessage(topic, packet=asDict, interface=self) # Our standard BLE characteristics TORADIO_UUID = "f75c76d2-129e-4dad-a1dd-7866124401e7" FROMRADIO_UUID = "8ba2bcc2-ee02-4a55-a531-c525c5e454d5" FROMNUM_UUID = "ed9da18c-a800-4f66-a670-aa7547e34453" class BLEInterface(MeshInterface): """A not quite ready - FIXME - BLE interface to devices""" def __init__(self, address, debugOut=None): self.address = address self.adapter = pygatt.GATTToolBackend() # BGAPIBackend() self.adapter.start() logging.debug(f"Connecting to {self.address}") self.device = self.adapter.connect(address) logging.debug("Connected to device") # fromradio = self.device.char_read(FROMRADIO_UUID) MeshInterface.__init__(self, debugOut=debugOut) self._readFromRadio() # read the initial responses def handle_data(handle, data): self._handleFromRadio(data) self.device.subscribe(FROMNUM_UUID, callback=handle_data) def _sendToRadio(self, toRadio): """Send a ToRadio protobuf to the device""" logging.debug(f"Sending: {toRadio}") b = toRadio.SerializeToString() self.device.char_write(TORADIO_UUID, b) def close(self): self.adapter.stop() def _readFromRadio(self): wasEmpty = False while not wasEmpty: b = self.device.char_read(FROMRADIO_UUID) wasEmpty = len(b) == 0 if not wasEmpty: self._handleFromRadio(b) class StreamInterface(MeshInterface): """Interface class for meshtastic devices over a stream link (serial, TCP, etc)""" def __init__(self, devPath=None, debugOut=None, noProto=False, connectNow=True): """Constructor, opens a connection to a specified serial port, or if unspecified try to find one Meshtastic device by probing Keyword Arguments: devPath {string} -- A filepath to a device, i.e. /dev/ttyUSB0 (default: {None}) debugOut {stream} -- If a stream is provided, any debug serial output from the device will be emitted to that stream. (default: {None}) Raises: Exception: [description] Exception: [description] """ if devPath is None: ports = util.findPorts() if len(ports) == 0: raise Exception("No Meshtastic devices detected") elif len(ports) > 1: raise Exception( f"Multiple ports detected, you must specify a device, such as {ports[0].device}") else: devPath = ports[0] logging.debug(f"Connecting to {devPath}") self.devPath = devPath self._rxBuf = bytes() # empty self._wantExit = False self.stream = serial.Serial( devPath, 921600, exclusive=True, timeout=0.5) self.stream.setRTS(False) self._rxThread = threading.Thread(target=self.__reader, args=()) MeshInterface.__init__(self, debugOut=debugOut, noProto=noProto) # Start the reader thread after superclass constructor completes init if connectNow: self.connect() def connect(self): """Connect to our radio Normally this is called automatically by the constructor, but if you passed in connectNow=False you can manually start the reading thread later. """ # Send some bogus UART characters to force a sleeping device to wake self.stream.write(bytes([START1, START1, START1, START1])) self.stream.flush() time.sleep(0.1) # wait 100ms to give device time to start running self._rxThread.start() def _sendToRadio(self, toRadio): """Send a ToRadio protobuf to the device""" logging.debug(f"Sending: {toRadio}") b = toRadio.SerializeToString() bufLen = len(b) header = bytes([START1, START2, (bufLen >> 8) & 0xff, bufLen & 0xff]) self.stream.write(header) self.stream.write(b) self.stream.flush() def close(self): """Close a connection to the device""" logging.debug("Closing serial stream") # pyserial cancel_read doesn't seem to work, therefore we ask the reader thread to close things for us self._wantExit = True if self._rxThread != threading.current_thread(): self._rxThread.join() # wait for it to exit def __reader(self): """The reader thread that reads bytes from our stream""" empty = bytes() try: while not self._wantExit: b = self.stream.read(1) if len(b) > 0: # logging.debug(f"read returned {b}") c = b[0] ptr = len(self._rxBuf) # Assume we want to append this byte, fixme use bytearray instead self._rxBuf = self._rxBuf + b if ptr == 0: # looking for START1 if c != START1: self._rxBuf = empty # failed to find start if self.debugOut != None: try: self.debugOut.write(b.decode("utf-8")) except: self.debugOut.write('?') elif ptr == 1: # looking for START2 if c != START2: self.rfBuf = empty # failed to find start2 elif ptr >= HEADER_LEN: # we've at least got a header # big endian length follos header packetlen = (self._rxBuf[2] << 8) + self._rxBuf[3] if ptr == HEADER_LEN: # we _just_ finished reading the header, validate length if packetlen > MAX_TO_FROM_RADIO_SIZE: self.rfBuf = empty # length ws out out bounds, restart if len(self._rxBuf) != 0 and ptr + 1 == packetlen + HEADER_LEN: try: self._handleFromRadio(self._rxBuf[HEADER_LEN:]) except Exception as ex: logging.error( f"Error while handling message from radio {ex}") traceback.print_exc() self._rxBuf = empty else: # logging.debug(f"timeout on {self.devPath}") pass except serial.SerialException as ex: logging.warn( "Meshtastic erial port disconnected, disconnecting...") finally: logging.debug("reader is exiting") self.stream.close() self._disconnected()