Extract queues from data_handler and modem.

Eliminates a cyclical import identified by pylint.

tnc/data_handler.py

@@ -8,7 +8,6 @@ Created on Sun Dec 27 20:43:40 2020
 # pylint: disable=import-outside-toplevel, attribute-defined-outside-init
 
 import base64
-import queue
 import sys
 import threading
 import time
@@ -26,13 +25,11 @@ import structlog
 import ujson as json
 from codec2 import FREEDV_MODE
 from exceptions import NoCallsign
+from queues import DATA_QUEUE_RECEIVED, DATA_QUEUE_TRANSMIT
 from static import FRAME_TYPE as FR_TYPE
 
 TESTMODE = False
 
-DATA_QUEUE_TRANSMIT = queue.Queue()
-DATA_QUEUE_RECEIVED = queue.Queue()
-
 
 class DATA:
     """Terminal Node Controller for FreeDATA"""

tnc/modem.py

@@ -11,28 +11,24 @@ Created on Wed Dec 23 07:04:24 2020
 import atexit
 import ctypes
 import os
-import queue
 import sys
 import threading
 import time
 from collections import deque
 
 import codec2
-import data_handler
 import numpy as np
 import sock
 import sounddevice as sd
 import static
 import structlog
 import ujson as json
+from queues import DATA_QUEUE_RECEIVED, MODEM_RECEIVED_QUEUE, MODEM_TRANSMIT_QUEUE
 
 TESTMODE = False
 RXCHANNEL = ""
 TXCHANNEL = ""
 
-# Initialize FIFO queue to store received frames
-MODEM_RECEIVED_QUEUE = queue.Queue()
-MODEM_TRANSMIT_QUEUE = queue.Queue()
 static.TRANSMITTING = False
 
 # Receive only specific modes to reduce CPU load
@@ -690,7 +686,7 @@ class RF:
             # data[0] = bytes_out
             # data[1] = freedv session
             # data[2] = bytes_per_frame
-            data_handler.DATA_QUEUE_RECEIVED.put([data[0], data[1], data[2]])
+            DATA_QUEUE_RECEIVED.put([data[0], data[1], data[2]])
             self.modem_received_queue.task_done()
 
     def get_frequency_offset(self, freedv: ctypes.c_void_p) -> float:

tnc/queues.py

@@ -0,0 +1,11 @@
+"""
+Hold queues used by more than one module to eliminate cyclic imports.
+"""
+import queue
+
+DATA_QUEUE_TRANSMIT = queue.Queue()
+DATA_QUEUE_RECEIVED = queue.Queue()
+
+# Initialize FIFO queue to store received frames
+MODEM_RECEIVED_QUEUE = queue.Queue()
+MODEM_TRANSMIT_QUEUE = queue.Queue()

tnc/sock.py

@@ -25,12 +25,12 @@ import sys
 import threading
 import time
 
-import data_handler
 import helpers
 import static
 import structlog
 import ujson as json
 from exceptions import NoCallsign
+from queues import DATA_QUEUE_TRANSMIT
 
 SOCKET_QUEUE = queue.Queue()
 DAEMON_QUEUE = queue.Queue()
@@ -227,7 +227,7 @@ def process_tnc_commands(data):
             and received_json["command"] == "send_test_frame"
         ):
             try:
-                data_handler.DATA_QUEUE_TRANSMIT.put(["SEND_TEST_FRAME"])
+                DATA_QUEUE_TRANSMIT.put(["SEND_TEST_FRAME"])
                 command_response("send_test_frame", True)
             except Exception as err:
                 command_response("send_test_frame", False)
@@ -240,7 +240,7 @@ def process_tnc_commands(data):
         # CQ CQ CQ -----------------------------------------------------
         if received_json["command"] == "cqcqcq":
             try:
-                data_handler.DATA_QUEUE_TRANSMIT.put(["CQ"])
+                DATA_QUEUE_TRANSMIT.put(["CQ"])
                 command_response("cqcqcq", True)
 
             except Exception as err:
@@ -254,7 +254,7 @@ def process_tnc_commands(data):
             try:
                 static.BEACON_STATE = True
                 interval = int(received_json["parameter"])
-                data_handler.DATA_QUEUE_TRANSMIT.put(["BEACON", interval, True])
+                DATA_QUEUE_TRANSMIT.put(["BEACON", interval, True])
                 command_response("start_beacon", True)
             except Exception as err:
                 command_response("start_beacon", False)
@@ -269,7 +269,7 @@ def process_tnc_commands(data):
             try:
                 log.warning("[SCK] Stopping beacon!")
                 static.BEACON_STATE = False
-                data_handler.DATA_QUEUE_TRANSMIT.put(["BEACON", None, False])
+                DATA_QUEUE_TRANSMIT.put(["BEACON", None, False])
                 command_response("stop_beacon", True)
             except Exception as err:
                 command_response("stop_beacon", False)
@@ -293,7 +293,7 @@ def process_tnc_commands(data):
                 dxcallsign = helpers.callsign_to_bytes(dxcallsign)
                 dxcallsign = helpers.bytes_to_callsign(dxcallsign)
 
-                data_handler.DATA_QUEUE_TRANSMIT.put(["PING", dxcallsign])
+                DATA_QUEUE_TRANSMIT.put(["PING", dxcallsign])
                 command_response("ping", True)
             except NoCallsign:
                 command_response("ping", False)
@@ -320,7 +320,7 @@ def process_tnc_commands(data):
                 static.DXCALLSIGN = dxcallsign
                 static.DXCALLSIGN_CRC = helpers.get_crc_24(static.DXCALLSIGN)
 
-                data_handler.DATA_QUEUE_TRANSMIT.put(["CONNECT", dxcallsign])
+                DATA_QUEUE_TRANSMIT.put(["CONNECT", dxcallsign])
                 command_response("connect", True)
             except Exception as err:
                 command_response("connect", False)
@@ -334,7 +334,7 @@ def process_tnc_commands(data):
         if received_json["type"] == "arq" and received_json["command"] == "disconnect":
             # send ping frame and wait for ACK
             try:
-                data_handler.DATA_QUEUE_TRANSMIT.put(["DISCONNECT"])
+                DATA_QUEUE_TRANSMIT.put(["DISCONNECT"])
                 command_response("disconnect", True)
             except Exception as err:
                 command_response("disconnect", False)
@@ -383,7 +383,7 @@ def process_tnc_commands(data):
 
                 binarydata = base64.b64decode(base64data)
 
-                data_handler.DATA_QUEUE_TRANSMIT.put(
+                DATA_QUEUE_TRANSMIT.put(
                     ["ARQ_RAW", binarydata, mode, n_frames, arq_uuid, mycallsign]
                 )
 
@@ -402,7 +402,7 @@ def process_tnc_commands(data):
         ):
             try:
                 if static.TNC_STATE == "BUSY" or static.ARQ_STATE:
-                    data_handler.DATA_QUEUE_TRANSMIT.put(["STOP"])
+                    DATA_QUEUE_TRANSMIT.put(["STOP"])
                 log.warning("[SCK] Stopping transmission!")
                 static.TNC_STATE = "IDLE"
                 static.ARQ_STATE = False