Device iterator

python/sbp/client/handler.py

@@ -138,6 +138,8 @@ def run(self):
         if msg is not None:
           if msg.msg_type:
             self.call(msg)
+      except SystemExit:
+        break
       except:
         import traceback
         traceback.print_exc()

python/sbp/client/loggers/device_iterator.py

@@ -0,0 +1,88 @@
+# Copyright (C) 2015 Swift Navigation Inc.
+# Contact: Mark Fine <mark@swiftnav.com>
+#
+# This source is subject to the license found in the file 'LICENSE' which must
+# be be distributed together with this source. All other rights reserved.
+#
+# THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND,
+# EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED
+# WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A PARTICULAR PURPOSE.
+
+from base_logger import LogIterator
+from ...client.handler import Handler
+from ...table import dispatch
+import calendar
+import time
+from Queue import Queue, Empty
+
+class DeviceIterator(LogIterator):
+  """
+  LogIterator
+
+  The :class: `DeviceIterator` provides an abstract interface for reading
+  from a handle and appending messages to a queue, and reading the queue
+  in an iterable fashion
+
+  Parameters
+  ----------
+  handler : Handler
+    SBP handler
+  timeout : float
+    number of seconds to block when reading queue before
+    raising stop iteration
+
+  """
+
+  def _enqueue(self, msg):
+    """
+    Called with each receipt of the message
+    Note: dispatch is necessary but perhaps should be handled in handler
+    """
+    try:
+      data = self.dispatcher(msg)
+    except KeyError:
+      data = msg
+    self.queue.put(data, True)
+
+  def __init__(self, handler, timeout=0, maxsize=0, dispatcher=dispatch):
+
+    self.handler = handler
+    self.queue = Queue(maxsize)
+    self.handler.add_callback(self._enqueue)
+    self.timeout = timeout
+    self.base_time = time.time()
+    self.dispatcher = dispatcher
+
+  def __iter__(self):
+    return self
+
+  def delta(self):
+    return time.time() - self.base_time
+
+  def timestamp(self):
+    """
+    Timestamp generator.
+    """
+    return calendar.timegm(time.gmtime())
+
+  def next(self):
+    """Return the next record tuple from the log file. If an unknown SBP
+    message type is found, it'll return the raw SBP. If the queue is empty,
+    It throws the StopIteration exception
+
+    Returns
+    -------
+    (float, float, object)
+      (elapsed msec since beginning of log, UTC timestamp, msg)
+
+    """
+    try:
+      msg = self.queue.get(True, self.timeout)
+      return (self.delta(), self.timestamp(), msg)
+    except Empty:
+      raise StopIteration
+
+
+
+
+

python/sbp/client/loggers/pickle_logger.py

@@ -7,7 +7,7 @@
 # THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND,
 # EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED
 # WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A PARTICULAR PURPOSE.
-
+from ... import SBP
 from .base_logger import BaseLogger, LogIterator
 import cPickle as pickle
 

python/tests/sbp/client/test_logger.py

@@ -13,9 +13,12 @@
 from sbp.client.loggers.base_logger import LogIterator
 from sbp.client.loggers.json_logger import JSONLogIterator, MultiJSONLogIterator
 from sbp.client.loggers.pickle_logger import PickleLogIterator
+from sbp.client.loggers.device_iterator import DeviceIterator
 from sbp.logging import SBP_MSG_PRINT
+from sbp.acquisition import SBP_MSG_ACQ_RESULT, MsgAcqResult
 from sbp.table import _SBP_TABLE, dispatch
 from sbp.table import InvalidSBPMessageType
+from sbp.client.handler import Handler
 import pytest
 import warnings
 
@@ -151,3 +154,17 @@ def test_msg_print():
       assert len(w) == 1
       assert issubclass(w[0].category, RuntimeWarning)
       assert str(w[0].message).startswith('Bad message parsing for line')
+
+def test_device_iterator():
+  """
+  device iterator sanity tests.
+  """
+  log_datafile = "data/one_msg.bin"
+  handle = open(log_datafile, 'r')
+  myhandler = Handler(handle.read, None, verbose=True)
+  mydevice_iterator = DeviceIterator(myhandler, 0.5)
+  myhandler.start()
+  for delta, timestamp, msg in mydevice_iterator:
+    assert delta > 0
+    assert timestamp >0
+    assert type(msg) == MsgAcqResult