operating_mode: fix packet reader function to correctly escape the bytes

- Transformed _unescape_data() method to public.
- Removed all unnecesary calls to unescape_data() from create_packet methods.
- Replaced __read_next_packet() method by a search in the xbee packet queue.

Signed-off-by: Héctor González <hector.gonzalez@digi.com>
Signed-off-by: Diego Escalona <diego.escalona@digi.com>

Author: hgonzaleDigi

digi/xbee/devices.py

@@ -1,4 +1,4 @@
-# Copyright 2017, Digi International Inc.
+# Copyright 2017, 2018, Digi International Inc.
 #
 # This Source Code Form is subject to the terms of the Mozilla Public
 # License, v. 2.0. If a copy of the MPL was not distributed with this
@@ -24,7 +24,6 @@
 
 from digi.xbee.packets.cellular import TXSMSPacket
 from digi.xbee.models.accesspoint import AccessPoint, WiFiEncryptionType
-from digi.xbee.models.atcomm import SpecialByte
 from digi.xbee.models.hw import HardwareVersion
 from digi.xbee.models.mode import OperatingMode, APIOutputMode, IPAddressingMode
 from digi.xbee.models.address import XBee64BitAddress, XBee16BitAddress, XBeeIMEIAddress
@@ -34,7 +33,6 @@
 from digi.xbee.models.status import ATCommandStatus, TransmitStatus, PowerLevel, \
     ModemStatus, CellularAssociationIndicationStatus, WiFiAssociationIndicationStatus, AssociationIndicationStatus,\
     NetworkDiscoveryStatus
-from digi.xbee.packets import factory
 from digi.xbee.packets.aft import ApiFrameType
 from digi.xbee.packets.common import ATCommPacket, TransmitPacket, RemoteATCommandPacket, ExplicitAddressingPacket
 from digi.xbee.packets.network import TXIPv4Packet
@@ -108,6 +106,8 @@ def __init__(self, local_xbee_device=None, serial_port=None, sync_ops_timeout=_D
         self._protocol = None
         self._node_id = None
 
+        self._packet_listener = None
+
         self._log.addHandler(logging.NullHandler())
 
         self.__generic_lock = threading.Lock()
@@ -1055,13 +1055,14 @@ def _get_packet_by_id(self, frame_id):
             ValueError: if ``frame_id`` is less than 0 or greater than 255.
             TimeoutException: if there was not any XBee packet matching the provided frame ID that could be read.
         """
-        operating_mode = OperatingMode.API_MODE if self.is_remote() else self._operating_mode
         if not (0 <= frame_id <= 255):
             raise ValueError("Frame ID must be between 0 and 255.")
-        packet_read = factory.build_frame(self.__read_next_packet(), operating_mode)
-        while not packet_read.needs_id() or packet_read.frame_id != frame_id:
-            packet_read = factory.build_frame(self.__read_next_packet(), operating_mode)
-        return packet_read
+
+        queue = self._packet_listener.get_queue()
+
+        packet = queue.get_by_id(frame_id, XBeeDevice.TIMEOUT_READ_PACKET)
+
+        return packet
 
     @staticmethod
     def __is_api_packet(xbee_packet):
@@ -1079,31 +1080,6 @@ def __is_api_packet(xbee_packet):
             return False
         return True
 
-    def __read_next_packet(self):
-        """
-        Reads the next XBee packet. Starts to read when finds the start delimiter.
-        The last byte read is the checksum.
-        
-        If there is something in the COM port buffer before the
-        start delimiter, this method discards it.
-        
-        Returns:
-            :class:XBeePacket: the next XBee packet read.
-            
-        Raises:
-            TimeoutException: if it could not read any new XBee packet.
-        """
-        xbee_packet = bytearray(1)
-        xbee_packet[0] = self._serial_port.read_byte()
-        while xbee_packet[0] != SpecialByte.HEADER_BYTE.code:
-            xbee_packet[0] = self._serial_port.read_byte()
-        packet_length = self._serial_port.read_bytes(2)
-        xbee_packet += packet_length
-        length = utils.length_to_int(packet_length)
-        xbee_packet += self._serial_port.read_bytes(length)
-        xbee_packet.append(self._serial_port.read_byte())
-        return xbee_packet
-
     def __get_log(self):
         """
         Returns the XBee device log.
@@ -1147,7 +1123,7 @@ class XBeeDevice(AbstractXBeeDevice):
     Timeout to wait when resetting the module.
     """
 
-    _TIMEOUT_READ_PACKET = 3  # seconds
+    TIMEOUT_READ_PACKET = 3  # seconds
     """
     Timeout to read packets.
     """
@@ -1203,7 +1179,6 @@ def __init__(self, port, baud_rate, data_bits=serial.EIGHTBITS, stop_bits=serial
 
         self._network = XBeeNetwork(self)
 
-        self._packet_listener = None
         self.__packet_queue = None
         self.__data_queue = None
         self.__explicit_queue = None
@@ -2463,7 +2438,7 @@ def send_packet(self, packet, sync=False):
         
         This method can be synchronous or asynchronous.
         
-        If is synchronous, this method  will discards all response
+        If is synchronous, this method  will discard all response
         packets until it finds the one that has the appropriate frame ID,
         that is, the sent packet's frame ID.
         
@@ -3481,7 +3456,7 @@ def send_ip_data_broadcast(self, dest_port, data):
         return self.send_ip_data(IPv4Address(self.BROADCAST_IP), dest_port, IPProtocol.UDP, data)
 
     @AbstractXBeeDevice._before_send_method
-    def read_ip_data(self, timeout=XBeeDevice._TIMEOUT_READ_PACKET):
+    def read_ip_data(self, timeout=XBeeDevice.TIMEOUT_READ_PACKET):
         """
         Reads new IP data received by this XBee device during the
         provided timeout.
@@ -3512,7 +3487,7 @@ def read_ip_data(self, timeout=XBeeDevice._TIMEOUT_READ_PACKET):
         return self.__read_ip_data_packet(timeout)
 
     @AbstractXBeeDevice._before_send_method
-    def read_ip_data_from(self, ip_addr, timeout=XBeeDevice._TIMEOUT_READ_PACKET):
+    def read_ip_data_from(self, ip_addr, timeout=XBeeDevice.TIMEOUT_READ_PACKET):
         """
         Reads new IP data received from the given IP address during the
         provided timeout.

digi/xbee/packets/base.py

@@ -1,4 +1,4 @@
-# Copyright 2017, Digi International Inc.
+# Copyright 2017, 2018, Digi International Inc.
 #
 # This Source Code Form is subject to the terms of the Mozilla Public
 # License, v. 2.0. If a copy of the MPL was not distributed with this
@@ -229,7 +229,7 @@ def _escape_data(data):
         return esc_data
 
     @staticmethod
-    def _unescape_data(data):
+    def unescape_data(data):
         """
         Un-escapes the provided bytearray data.
 
@@ -482,15 +482,13 @@ def create_packet(raw, operating_mode=OperatingMode.API_MODE):
         if operating_mode != OperatingMode.ESCAPED_API_MODE and operating_mode != OperatingMode.API_MODE:
             raise InvalidOperatingModeException(operating_mode + " is not supported.")
 
-        unesc_raw = XBeeAPIPacket._unescape_data(raw) if operating_mode == OperatingMode.ESCAPED_API_MODE else raw
+        XBeeAPIPacket._check_api_packet(raw, min_length=GenericXBeePacket.__MIN_PACKET_LENGTH)
 
-        XBeeAPIPacket._check_api_packet(unesc_raw, min_length=GenericXBeePacket.__MIN_PACKET_LENGTH)
-
-        if unesc_raw[3] != ApiFrameType.GENERIC.code:
+        if raw[3] != ApiFrameType.GENERIC.code:
             raise InvalidPacketException("Wrong frame type, expected: " + ApiFrameType.GENERIC.description +
                                          ". Value: " + ApiFrameType.GENERIC.code)
 
-        return GenericXBeePacket(unesc_raw[4:-1])
+        return GenericXBeePacket(raw[4:-1])
 
     def _get_api_packet_spec_data(self):
         """

digi/xbee/packets/cellular.py

@@ -1,4 +1,4 @@
-# Copyright 2017, Digi International Inc.
+# Copyright 2017, 2018, Digi International Inc.
 #
 # This Source Code Form is subject to the terms of the Mozilla Public
 # License, v. 2.0. If a copy of the MPL was not distributed with this
@@ -83,13 +83,12 @@ def create_packet(raw, operating_mode):
         if operating_mode != OperatingMode.ESCAPED_API_MODE and operating_mode != OperatingMode.API_MODE:
             raise InvalidOperatingModeException(operating_mode.name + " is not supported.")
 
-        _raw = XBeeAPIPacket._unescape_data(raw) if operating_mode == OperatingMode.ESCAPED_API_MODE else raw
-        
-        XBeeAPIPacket._check_api_packet(_raw, min_length=RXSMSPacket.__MIN_PACKET_LENGTH)
-        if _raw[3] != ApiFrameType.RX_SMS.code:
+        XBeeAPIPacket._check_api_packet(raw, min_length=RXSMSPacket.__MIN_PACKET_LENGTH)
+
+        if raw[3] != ApiFrameType.RX_SMS.code:
             raise InvalidPacketException("This packet is not an RXSMSPacket")
 
-        return RXSMSPacket(_raw[4:23].decode("utf8").replace("\0", ""), _raw[24:-1].decode("utf8"))
+        return RXSMSPacket(raw[4:23].decode("utf8").replace("\0", ""), raw[24:-1].decode("utf8"))
 
     def needs_id(self):
         """
@@ -252,13 +251,12 @@ def create_packet(raw, operating_mode):
         if operating_mode != OperatingMode.ESCAPED_API_MODE and operating_mode != OperatingMode.API_MODE:
             raise InvalidOperatingModeException(operating_mode.name + " is not supported.")
 
-        _raw = XBeeAPIPacket._unescape_data(raw) if operating_mode == OperatingMode.ESCAPED_API_MODE else raw
-        
         XBeeAPIPacket._check_api_packet(raw, min_length=TXSMSPacket.__MIN_PACKET_LENGTH)
-        if _raw[3] != ApiFrameType.TX_SMS.code:
+
+        if raw[3] != ApiFrameType.TX_SMS.code:
             raise InvalidPacketException("This packet is not a TXSMSPacket")
 
-        return TXSMSPacket(_raw[4], _raw[6:25].decode("utf8").replace("\0", ""), _raw[26:-1].decode("utf8"))
+        return TXSMSPacket(raw[4], raw[6:25].decode("utf8").replace("\0", ""), raw[26:-1].decode("utf8"))
 
     def needs_id(self):
         """

digi/xbee/packets/common.py

@@ -1,4 +1,4 @@
-# Copyright 2017, Digi International Inc.
+# Copyright 2017, 2018, Digi International Inc.
 #
 # This Source Code Form is subject to the terms of the Mozilla Public
 # License, v. 2.0. If a copy of the MPL was not distributed with this
@@ -91,7 +91,6 @@ def create_packet(raw, operating_mode):
         if operating_mode != OperatingMode.ESCAPED_API_MODE and operating_mode != OperatingMode.API_MODE:
             raise InvalidOperatingModeException(operating_mode.name + " is not supported.")
 
-        raw = XBeeAPIPacket._unescape_data(raw) if operating_mode == OperatingMode.ESCAPED_API_MODE else raw
         XBeeAPIPacket._check_api_packet(raw, min_length=ATCommPacket.__MIN_PACKET_LENGTH)
 
         if raw[3] != ApiFrameType.AT_COMMAND.code:
@@ -253,8 +252,6 @@ def create_packet(raw, operating_mode):
         if operating_mode != OperatingMode.ESCAPED_API_MODE and operating_mode != OperatingMode.API_MODE:
             raise InvalidOperatingModeException(operating_mode.name + " is not supported.")
 
-        raw = XBeeAPIPacket._unescape_data(raw) if operating_mode == OperatingMode.ESCAPED_API_MODE else raw
-
         XBeeAPIPacket._check_api_packet(raw, min_length=ATCommResponsePacket.__MIN_PACKET_LENGTH)
 
         if raw[3] != ApiFrameType.AT_COMMAND_RESPONSE.code:
@@ -441,8 +438,6 @@ def create_packet(raw, operating_mode):
         if operating_mode != OperatingMode.ESCAPED_API_MODE and operating_mode != OperatingMode.API_MODE:
             raise InvalidOperatingModeException(operating_mode.name + " is not supported.")
 
-        raw = XBeeAPIPacket._unescape_data(raw) if operating_mode == OperatingMode.ESCAPED_API_MODE else raw
-
         XBeeAPIPacket._check_api_packet(raw, min_length=ReceivePacket.__MIN_PACKET_LENGTH)
 
         if raw[3] != ApiFrameType.RECEIVE_PACKET.code:
@@ -678,8 +673,6 @@ def create_packet(raw, operating_mode):
         if operating_mode != OperatingMode.ESCAPED_API_MODE and operating_mode != OperatingMode.API_MODE:
             raise InvalidOperatingModeException(operating_mode.name + " is not supported.")
 
-        raw = XBeeAPIPacket._unescape_data(raw) if operating_mode == OperatingMode.ESCAPED_API_MODE else raw
-
         XBeeAPIPacket._check_api_packet(raw, min_length=RemoteATCommandPacket.__MIN_PACKET_LENGTH)
 
         if raw[3] != ApiFrameType.REMOTE_AT_COMMAND_REQUEST.code:
@@ -937,8 +930,6 @@ def create_packet(raw, operating_mode):
         if operating_mode != OperatingMode.ESCAPED_API_MODE and operating_mode != OperatingMode.API_MODE:
             raise InvalidOperatingModeException(operating_mode.name + " is not supported.")
 
-        raw = XBeeAPIPacket._unescape_data(raw) if operating_mode == OperatingMode.ESCAPED_API_MODE else raw
-
         XBeeAPIPacket._check_api_packet(raw, min_length=RemoteATCommandResponsePacket.__MIN_PACKET_LENGTH)
 
         if raw[3] != ApiFrameType.REMOTE_AT_COMMAND_RESPONSE.code:
@@ -1211,8 +1202,6 @@ def create_packet(raw, operating_mode):
         if operating_mode != OperatingMode.ESCAPED_API_MODE and operating_mode != OperatingMode.API_MODE:
             raise InvalidOperatingModeException(operating_mode.name + " is not supported.")
 
-        raw = XBeeAPIPacket._unescape_data(raw) if operating_mode == OperatingMode.ESCAPED_API_MODE else raw
-
         XBeeAPIPacket._check_api_packet(raw, min_length=TransmitPacket.__MIN_PACKET_LENGTH)
 
         if raw[3] != ApiFrameType.TRANSMIT_REQUEST.code:
@@ -1463,8 +1452,6 @@ def create_packet(raw, operating_mode):
         if operating_mode != OperatingMode.ESCAPED_API_MODE and operating_mode != OperatingMode.API_MODE:
             raise InvalidOperatingModeException(operating_mode.name + " is not supported.")
 
-        raw = XBeeAPIPacket._unescape_data(raw) if operating_mode == OperatingMode.ESCAPED_API_MODE else raw
-
         XBeeAPIPacket._check_api_packet(raw, min_length=TransmitStatusPacket.__MIN_PACKET_LENGTH)
 
         if raw[3] != ApiFrameType.TRANSMIT_STATUS.code:
@@ -1663,8 +1650,6 @@ def create_packet(raw, operating_mode):
         if operating_mode != OperatingMode.ESCAPED_API_MODE and operating_mode != OperatingMode.API_MODE:
             raise InvalidOperatingModeException(operating_mode.name + " is not supported.")
 
-        raw = XBeeAPIPacket._unescape_data(raw) if operating_mode == OperatingMode.ESCAPED_API_MODE else raw
-
         XBeeAPIPacket._check_api_packet(raw, min_length=ModemStatusPacket.__MIN_PACKET_LENGTH)
 
         if raw[3] != ApiFrameType.MODEM_STATUS.code:
@@ -1799,8 +1784,6 @@ def create_packet(raw, operating_mode):
         if operating_mode != OperatingMode.ESCAPED_API_MODE and operating_mode != OperatingMode.API_MODE:
             raise InvalidOperatingModeException(operating_mode.name + " is not supported.")
 
-        raw = XBeeAPIPacket._unescape_data(raw) if operating_mode == OperatingMode.ESCAPED_API_MODE else raw
-
         XBeeAPIPacket._check_api_packet(raw, min_length=IODataSampleRxIndicatorPacket.__MIN_PACKET_LENGTH)
 
         if raw[3] != ApiFrameType.IO_DATA_SAMPLE_RX_INDICATOR.code:
@@ -2150,7 +2133,6 @@ def create_packet(raw, operating_mode):
         if operating_mode != OperatingMode.ESCAPED_API_MODE and operating_mode != OperatingMode.API_MODE:
             raise InvalidOperatingModeException(operating_mode.name + " is not supported.")
 
-        raw = XBeeAPIPacket._unescape_data(raw) if operating_mode == OperatingMode.ESCAPED_API_MODE else raw
         XBeeAPIPacket._check_api_packet(raw, min_length=ExplicitAddressingPacket.__MIN_PACKET_LENGTH)
 
         if raw[3] != ApiFrameType.EXPLICIT_ADDRESSING.code:
@@ -2511,7 +2493,6 @@ def create_packet(raw, operating_mode):
         if operating_mode != OperatingMode.ESCAPED_API_MODE and operating_mode != OperatingMode.API_MODE:
             raise InvalidOperatingModeException(operating_mode.name + " is not supported.")
 
-        raw = XBeeAPIPacket._unescape_data(raw) if operating_mode == OperatingMode.ESCAPED_API_MODE else raw
         XBeeAPIPacket._check_api_packet(raw, min_length=ExplicitRXIndicatorPacket.__MIN_PACKET_LENGTH)
 
         if raw[3] != ApiFrameType.EXPLICIT_RX_INDICATOR.code:

digi/xbee/packets/devicecloud.py

@@ -1,4 +1,4 @@
-# Copyright 2017, Digi International Inc.
+# Copyright 2017, 2018, Digi International Inc.
 #
 # This Source Code Form is subject to the terms of the Mozilla Public
 # License, v. 2.0. If a copy of the MPL was not distributed with this
@@ -90,7 +90,6 @@ def create_packet(raw, operating_mode):
         if operating_mode != OperatingMode.ESCAPED_API_MODE and operating_mode != OperatingMode.API_MODE:
             raise InvalidOperatingModeException(operating_mode.name + " is not supported.")
 
-        raw = XBeeAPIPacket._unescape_data(raw) if operating_mode == OperatingMode.ESCAPED_API_MODE else raw
         XBeeAPIPacket._check_api_packet(raw, min_length=DeviceRequestPacket.__MIN_PACKET_LENGTH)
 
         if raw[3] != ApiFrameType.DEVICE_REQUEST.code:
@@ -312,7 +311,6 @@ def create_packet(raw, operating_mode):
         if operating_mode != OperatingMode.ESCAPED_API_MODE and operating_mode != OperatingMode.API_MODE:
             raise InvalidOperatingModeException(operating_mode.name + " is not supported.")
 
-        raw = XBeeAPIPacket._unescape_data(raw) if operating_mode == OperatingMode.ESCAPED_API_MODE else raw
         XBeeAPIPacket._check_api_packet(raw, min_length=DeviceResponsePacket.__MIN_PACKET_LENGTH)
 
         if raw[3] != ApiFrameType.DEVICE_RESPONSE.code:
@@ -469,7 +467,6 @@ def create_packet(raw, operating_mode):
         if operating_mode != OperatingMode.ESCAPED_API_MODE and operating_mode != OperatingMode.API_MODE:
             raise InvalidOperatingModeException(operating_mode.name + " is not supported.")
 
-        raw = XBeeAPIPacket._unescape_data(raw) if operating_mode == OperatingMode.ESCAPED_API_MODE else raw
         XBeeAPIPacket._check_api_packet(raw, min_length=DeviceResponseStatusPacket.__MIN_PACKET_LENGTH)
 
         if raw[3] != ApiFrameType.DEVICE_RESPONSE_STATUS.code:
@@ -585,7 +582,6 @@ def create_packet(raw, operating_mode):
         if operating_mode != OperatingMode.ESCAPED_API_MODE and operating_mode != OperatingMode.API_MODE:
             raise InvalidOperatingModeException(operating_mode.name + " is not supported.")
 
-        raw = XBeeAPIPacket._unescape_data(raw) if operating_mode == OperatingMode.ESCAPED_API_MODE else raw
         XBeeAPIPacket._check_api_packet(raw, min_length=FrameErrorPacket.__MIN_PACKET_LENGTH)
 
         if raw[3] != ApiFrameType.FRAME_ERROR.code:
@@ -719,7 +715,6 @@ def create_packet(raw, operating_mode):
         if operating_mode != OperatingMode.ESCAPED_API_MODE and operating_mode != OperatingMode.API_MODE:
             raise InvalidOperatingModeException(operating_mode.name + " is not supported.")
 
-        raw = XBeeAPIPacket._unescape_data(raw) if operating_mode == OperatingMode.ESCAPED_API_MODE else raw
         XBeeAPIPacket._check_api_packet(raw, min_length=SendDataRequestPacket.__MIN_PACKET_LENGTH)
 
         if raw[3] != ApiFrameType.SEND_DATA_REQUEST.code:
@@ -939,7 +934,6 @@ def create_packet(raw, operating_mode):
         if operating_mode != OperatingMode.ESCAPED_API_MODE and operating_mode != OperatingMode.API_MODE:
             raise InvalidOperatingModeException(operating_mode.name + " is not supported.")
 
-        raw = XBeeAPIPacket._unescape_data(raw) if operating_mode == OperatingMode.ESCAPED_API_MODE else raw
         XBeeAPIPacket._check_api_packet(raw, min_length=SendDataResponsePacket.__MIN_PACKET_LENGTH)
 
         if raw[3] != ApiFrameType.SEND_DATA_RESPONSE.code: