def test_failed_conversion(self):
channel_type = "int32"
compression = None
endianness = "<"
value = 10
value_reader = get_value_reader(channel_type,
compression,
shape=None,
endianness=endianness)
result = value_reader(value.to_bytes(4, byteorder='little'))
self.assertEqual(value, result)
result = value_reader(value.to_bytes(3, byteorder='little'))
self.assertEqual(None, result)
def get_channel_reader(channel):
"""
Construct a value reader for the provided channel.
:param channel: Channel to construct the value reader for.
:return: Value reader.
"""
# If no channel type is specified, float64 is assumed.
channel_type = channel['type'].lower() if 'type' in channel else None
if channel_type is None:
_logger.warning(
"'type' channel field not found. Parse as 64-bit floating-point number float64 (default)."
)
channel_type = "float64"
name = channel['name']
compression = channel['compression'] if "compression" in channel else None
shape = channel['shape'] if "shape" in channel else None
endianness = channel['encoding']
value_reader = get_value_reader(channel_type, compression, shape,
endianness, name)
return value_reader
def receive(self, receiver):
# Receive main header
header = receiver.next(as_json=True)
changed = False
# We cannot process an empty Header.
if not header:
return None
message = Message()
message.pulse_id = header['pulse_id']
message.hash = header['hash']
if 'global_timestamp' in header:
if 'sec' in header['global_timestamp']:
message.global_timestamp = header['global_timestamp']['sec']
elif 'epoch' in header['global_timestamp']:
message.global_timestamp = header['global_timestamp']['epoch']
else:
raise RuntimeError(
"Invalid timestamp format in BSDATA header message {}".
format(message))
message.global_timestamp_offset = header['global_timestamp']['ns']
# Receiver data header, check if header has changed - and in this case recreate the channel definitions.
if receiver.has_more() and (self.data_header_hash != header['hash']):
changed = self.data_header_hash is not None
# Set the current header hash as the new hash.
self.data_header_hash = header['hash']
# Read the data header.
data_header_bytes = receiver.next()
data_header = json.loads(
get_value_reader("string",
header.get('dh_compression'),
value_name="data_header")(data_header_bytes))
# If a message with ho channel information is received,
# ignore it and return from function with no data.
if not data_header['channels']:
logging.warning("Received message without channels.")
while receiver.has_more():
# Drain rest of the messages - if entering this code there is actually something wrong
receiver.next()
return message
# TODO: Why do we need to pre-process the message? Source change?
for channel in data_header['channels']:
# Define endianness of data
# > - big endian
# < - little endian (default)
channel["encoding"] = '>' if channel.get(
"encoding") == "big" else '<'
# Construct the channel definitions.
self.channels_definitions = [(channel["name"], channel["encoding"],
get_channel_reader(channel))
for channel in data_header['channels']
]
# Signal that the format has changed.
message.format_changed = True
else:
# Skip second header - we already have the receive functions setup.
receiver.next()
# Receiving data
counter = 0
# Todo add some more error checking
while receiver.has_more():
channel_name, channel_endianness, channel_reader = self.channels_definitions[
counter]
raw_data = receiver.next()
channel_value = Value()
if raw_data:
channel_value.value = channel_reader(raw_data)
if receiver.has_more():
raw_timestamp = receiver.next()
if raw_timestamp:
timestamp_array = numpy.frombuffer(
raw_timestamp, dtype=channel_endianness + 'u8')
channel_value.timestamp = timestamp_array[
0] # Second past epoch
channel_value.timestamp_offset = timestamp_array[
1] # Nanoseconds offset
else:
# Consume empty timestamp message
if receiver.has_more():
receiver.next() # Read empty timestamp message
message.data[channel_name] = channel_value
counter += 1
if changed:
if self.data_change_callback is not None:
self.data_change_callback(data_header['channels'])
return message
def receive(self, receiver):
header = receiver.next(as_json=True)
# We cannot process an empty Header.
if not header:
return None
return_value = {}
data = []
timestamp = []
timestamp_offset = []
pulse_ids = []
pulse_id_array = [] # array of all pulse ids
pulse_id = header['pulse_id']
pulse_id_array.append(pulse_id)
if receiver.has_more() and (self.data_header_hash != header['hash']):
self.data_header_hash = header['hash']
# Read the data header.
data_header_bytes = receiver.next()
data_header = json.loads(
get_value_reader("string",
header.get('dh_compression'),
value_name="data_header")(data_header_bytes))
# If a message with ho channel information is received,
# ignore it and return from function with no data.
if not data_header['channels']:
logging.warning("Received message without channels.")
while receiver.has_more():
receiver.next()
return_value['header'] = header
return_value['pulse_id_array'] = pulse_id_array
return_value['data'] = 'No channel'
return_value['timestamp'] = None
return_value['timestamp_offset'] = None
return_value['pulse_ids'] = None
return return_value
# TODO: Why do we need to pre-process the message? Source change?
for channel in data_header['channels']:
# Define endianness of data
# > - big endian
# < - little endian (default)
channel["encoding"] = '>' if channel.get(
"encoding") == "big" else '<'
# Construct the channel definitions.
self.channels_definitions = [(channel["name"], channel["encoding"],
get_channel_reader(channel))
for channel in data_header['channels']
]
self.data_header = data_header
else:
# Skip second header
receiver.next()
# The data header should be added to every message.
return_value['data_header'] = self.data_header
# Receiving data
counter = 0
# msg_data_size = 0
while receiver.has_more():
channel_name, channel_endianness, channel_reader = self.channels_definitions[
counter]
raw_data = receiver.next()
if raw_data:
pulse_ids.append(pulse_id)
data.append(channel_reader(raw_data))
if receiver.has_more():
raw_timestamp = receiver.next()
if raw_timestamp:
timestamp_array = numpy.frombuffer(
raw_timestamp, dtype=channel_endianness + 'u8')
timestamp.append(
timestamp_array[0]) # Second past epoch
timestamp_offset.append(
timestamp_array[1]) # Nanoseconds offset
else:
if receiver.has_more():
receiver.next() # Read empty timestamp message
data.append(None)
timestamp.append(None)
timestamp_offset.append(None)
pulse_ids.append(None)
counter += 1
# Todo need to add some more error checking
return_value['header'] = header
return_value['pulse_id_array'] = pulse_id_array
return_value['data'] = data
return_value['timestamp'] = timestamp
return_value['timestamp_offset'] = timestamp_offset
return_value['pulse_ids'] = pulse_ids
# return_value['size'] = msg_data_size
return return_value