Source code for

Contains handling of ASC logging files.

Example .asc files:
    - under `test/data/logfile.asc`
import re
from typing import Any, Generator, List, Optional, Dict, Union, TextIO

from datetime import datetime
import time
import logging

from ..message import Message
from ..util import channel2int, len2dlc, dlc2len
from .generic import FileIOMessageWriter, MessageReader
from ..typechecking import StringPathLike

CAN_MSG_EXT = 0x80000000

logger = logging.getLogger("")

[docs]class ASCReader(MessageReader): """ Iterator of CAN messages from a ASC logging file. Meta data (comments, bus statistics, J1939 Transport Protocol messages) is ignored. """ file: TextIO def __init__( self, file: Union[StringPathLike, TextIO], base: str = "hex", relative_timestamp: bool = True, *args: Any, **kwargs: Any, ) -> None: """ :param file: a path-like object or as file-like object to read from If this is a file-like object, is has to opened in text read mode, not binary read mode. :param base: Select the base(hex or dec) of id and data. If the header of the asc file contains base information, this value will be overwritten. Default "hex". :param relative_timestamp: Select whether the timestamps are `relative` (starting at 0.0) or `absolute` (starting at the system time). Default `True = relative`. """ super().__init__(file, mode="r") if not self.file: raise ValueError("The given file cannot be None") self.base = base self._converted_base = self._check_base(base) self.relative_timestamp = relative_timestamp Optional[str] = None self.start_time = 0.0 # TODO - what is this used for? The ASC Writer only prints `absolute` self.timestamps_format: Optional[str] = None self.internal_events_logged = False def _extract_header(self) -> None: for line in self.file: line = line.strip() datetime_match = re.match( r"date\s+\w+\s+(?P<datetime_string>.+)", line, re.IGNORECASE ) base_match = re.match( r"base\s+(?P<base>hex|dec)(?:\s+timestamps\s+" r"(?P<timestamp_format>absolute|relative))?", line, re.IGNORECASE, ) comment_match = re.match(r"//.*", line) events_match = re.match( r"(?P<no_events>no)?\s*internal\s+events\s+logged", line, re.IGNORECASE ) if datetime_match: ="datetime_string") self.start_time = ( 0.0 if self.relative_timestamp else self._datetime_to_timestamp( ) continue elif base_match: base ="base") timestamp_format ="timestamp_format") self.base = base self._converted_base = self._check_base(self.base) self.timestamps_format = timestamp_format or "absolute" continue elif comment_match: continue elif events_match: self.internal_events_logged ="no_events") is None break else: break @staticmethod def _datetime_to_timestamp(datetime_string: str) -> float: # ugly locale independent solution month_map = { "Jan": 1, "Feb": 2, "Mar": 3, "Apr": 4, "May": 5, "Jun": 6, "Jul": 7, "Aug": 8, "Sep": 9, "Oct": 10, "Nov": 11, "Dec": 12, "Mär": 3, "Mai": 5, "Okt": 10, "Dez": 12, } for name, number in month_map.items(): datetime_string = datetime_string.replace(name, str(number).zfill(2)) datetime_formats = ( "%m %d %I:%M:%S.%f %p %Y", "%m %d %I:%M:%S %p %Y", "%m %d %H:%M:%S.%f %Y", "%m %d %H:%M:%S %Y", ) for format_str in datetime_formats: try: return datetime.strptime(datetime_string, format_str).timestamp() except ValueError: continue raise ValueError(f"Incompatible datetime string {datetime_string}") def _extract_can_id(self, str_can_id: str, msg_kwargs: Dict[str, Any]) -> None: if str_can_id[-1:].lower() == "x": msg_kwargs["is_extended_id"] = True can_id = int(str_can_id[0:-1], self._converted_base) else: msg_kwargs["is_extended_id"] = False can_id = int(str_can_id, self._converted_base) msg_kwargs["arbitration_id"] = can_id @staticmethod def _check_base(base: str) -> int: if base not in ["hex", "dec"]: raise ValueError('base should be either "hex" or "dec"') return BASE_DEC if base == "dec" else BASE_HEX def _process_data_string( self, data_str: str, data_length: int, msg_kwargs: Dict[str, Any] ) -> None: frame = bytearray() data = data_str.split() for byte in data[:data_length]: frame.append(int(byte, self._converted_base)) msg_kwargs["data"] = frame def _process_classic_can_frame( self, line: str, msg_kwargs: Dict[str, Any] ) -> Message: # CAN error frame if line.strip()[0:10].lower() == "errorframe": # Error Frame msg_kwargs["is_error_frame"] = True else: abr_id_str, direction, rest_of_message = line.split(None, 2) msg_kwargs["is_rx"] = direction == "Rx" self._extract_can_id(abr_id_str, msg_kwargs) if rest_of_message[0].lower() == "r": # CAN Remote Frame msg_kwargs["is_remote_frame"] = True remote_data = rest_of_message.split() if len(remote_data) > 1: dlc_str = remote_data[1] if dlc_str.isdigit(): msg_kwargs["dlc"] = int(dlc_str, self._converted_base) else: # Classic CAN Message try: # There is data after DLC _, dlc_str, data = rest_of_message.split(None, 2) except ValueError: # No data after DLC _, dlc_str = rest_of_message.split(None, 1) data = "" dlc = dlc2len(int(dlc_str, self._converted_base)) msg_kwargs["dlc"] = dlc self._process_data_string(data, min(8, dlc), msg_kwargs) return Message(**msg_kwargs) def _process_fd_can_frame(self, line: str, msg_kwargs: Dict[str, Any]) -> Message: channel, direction, rest_of_message = line.split(None, 2) # See ASCWriter msg_kwargs["channel"] = int(channel) - 1 msg_kwargs["is_rx"] = direction == "Rx" # CAN FD error frame if rest_of_message.strip()[:10].lower() == "errorframe": # Error Frame # TODO: maybe use regex to parse BRS, ESI, etc? msg_kwargs["is_error_frame"] = True else: can_id_str, frame_name_or_brs, rest_of_message = rest_of_message.split( None, 2 ) if frame_name_or_brs.isdigit(): brs = frame_name_or_brs esi, dlc_str, data_length_str, data = rest_of_message.split(None, 3) else: brs, esi, dlc_str, data_length_str, data = rest_of_message.split( None, 4 ) self._extract_can_id(can_id_str, msg_kwargs) msg_kwargs["bitrate_switch"] = brs == "1" msg_kwargs["error_state_indicator"] = esi == "1" dlc = int(dlc_str, self._converted_base) data_length = int(data_length_str) if data_length == 0: # CAN remote Frame msg_kwargs["is_remote_frame"] = True msg_kwargs["dlc"] = dlc else: if dlc2len(dlc) != data_length: logger.warning( "DLC vs Data Length mismatch %d[%d] != %d", dlc, dlc2len(dlc), data_length, ) msg_kwargs["dlc"] = data_length self._process_data_string(data, data_length, msg_kwargs) return Message(**msg_kwargs) def __iter__(self) -> Generator[Message, None, None]: self._extract_header() for line in self.file: line = line.strip() trigger_match = re.match( r"begin\s+triggerblock\s+\w+\s+(?P<datetime_string>.+)", line, re.IGNORECASE, ) if trigger_match: datetime_str ="datetime_string") self.start_time = ( 0.0 if self.relative_timestamp else self._datetime_to_timestamp(datetime_str) ) continue if not re.match( r"\d+\.\d+\s+(\d+\s+(\w+\s+(Tx|Rx)|ErrorFrame)|CANFD)", line, re.ASCII | re.IGNORECASE, ): # line might be a comment, chip status, # J1939 message or some other unsupported event continue msg_kwargs: Dict[str, Union[float, bool, int]] = {} try: _timestamp, channel, rest_of_message = line.split(None, 2) timestamp = float(_timestamp) + self.start_time msg_kwargs["timestamp"] = timestamp if channel == "CANFD": msg_kwargs["is_fd"] = True elif channel.isdigit(): # See ASCWriter msg_kwargs["channel"] = int(channel) - 1 else: # Not a CAN message. Possible values include "statistic", J1939TP continue except ValueError: # Some other unprocessed or unknown format continue if "is_fd" not in msg_kwargs: msg = self._process_classic_can_frame(rest_of_message, msg_kwargs) else: msg = self._process_fd_can_frame(rest_of_message, msg_kwargs) if msg is not None: yield msg self.stop()
[docs]class ASCWriter(FileIOMessageWriter): """Logs CAN data to an ASCII log file (.asc). The measurement starts with the timestamp of the first registered message. If a message has a timestamp smaller than the previous one or None, it gets assigned the timestamp that was written for the last message. It the first message does not have a timestamp, it is set to zero. """ file: TextIO FORMAT_MESSAGE = "{channel} {id:<15} {dir:<4} {dtype} {data}" FORMAT_MESSAGE_FD = " ".join( [ "CANFD", "{channel:>3}", "{dir:<4}", "{id:>8} {symbolic_name:>32}", "{brs}", "{esi}", "{dlc:x}", "{data_length:>2}", "{data}", "{message_duration:>8}", "{message_length:>4}", "{flags:>8X}", "{crc:>8}", "{bit_timing_conf_arb:>8}", "{bit_timing_conf_data:>8}", "{bit_timing_conf_ext_arb:>8}", "{bit_timing_conf_ext_data:>8}", ] ) FORMAT_START_OF_FILE_DATE = "%a %b %d %I:%M:%S.%f %p %Y" FORMAT_DATE = "%a %b %d %I:%M:%S.{} %p %Y" FORMAT_EVENT = "{timestamp: 9.6f} {message}\n" def __init__( self, file: Union[StringPathLike, TextIO], channel: int = 1, *args: Any, **kwargs: Any, ) -> None: """ :param file: a path-like object or as file-like object to write to If this is a file-like object, is has to opened in text write mode, not binary write mode. :param channel: a default channel to use when the message does not have a channel set """ if kwargs.get("append", False): raise ValueError( f"{self.__class__.__name__} is currently not equipped to " f"append messages to an existing file." ) super().__init__(file, mode="w") = channel # write start of file header now = # Note: CANoe requires that the microsecond field only have 3 digits idx = now.index(".") # Find the index in the string of the decimal # Keep decimal and first three ms digits (4), remove remaining digits now = now.replace(now[idx + 4 : now[idx:].index(" ") + idx], "") self.file.write(f"date {now}\n") self.file.write("base hex timestamps absolute\n") self.file.write("internal events logged\n") # the last part is written with the timestamp of the first message self.header_written = False self.last_timestamp = 0.0 self.started = 0.0
[docs] def stop(self) -> None: # This is guaranteed to not be None since we raise ValueError in __init__ if not self.file.closed: self.file.write("End TriggerBlock\n") super().stop()
[docs] def log_event(self, message: str, timestamp: Optional[float] = None) -> None: """Add a message to the log file. :param message: an arbitrary message :param timestamp: the absolute timestamp of the event """ if not message: # if empty or None logger.debug("ASCWriter: ignoring empty message") return # this is the case for the very first message: if not self.header_written: self.last_timestamp = timestamp or 0.0 self.started = self.last_timestamp mlsec = repr(self.last_timestamp).split(".")[1][:3] formatted_date = time.strftime( self.FORMAT_DATE.format(mlsec), time.localtime(self.last_timestamp) ) self.file.write(f"Begin Triggerblock {formatted_date}\n") self.header_written = True self.log_event("Start of measurement") # caution: this is a recursive call! # Use last known timestamp if unknown if timestamp is None: timestamp = self.last_timestamp # turn into relative timestamps if necessary if timestamp >= self.started: timestamp -= self.started line = self.FORMAT_EVENT.format(timestamp=timestamp, message=message) self.file.write(line)
[docs] def on_message_received(self, msg: Message) -> None: if msg.is_error_frame: self.log_event(f"{} ErrorFrame", msg.timestamp) return if msg.is_remote_frame: dtype = f"r {msg.dlc:x}" # New after v8.5 data: List[str] = [] else: dtype = f"d {msg.dlc:x}" data = [f"{byte:02X}" for byte in] arb_id = f"{msg.arbitration_id:X}" if msg.is_extended_id: arb_id += "x" channel = channel2int( if channel is None: channel = else: # Many interfaces start channel numbering at 0 which is invalid channel += 1 if msg.is_fd: flags = 0 flags |= 1 << 12 if msg.bitrate_switch: flags |= 1 << 13 if msg.error_state_indicator: flags |= 1 << 14 serialized = self.FORMAT_MESSAGE_FD.format( channel=channel, id=arb_id, dir="Rx" if msg.is_rx else "Tx", symbolic_name="", brs=1 if msg.bitrate_switch else 0, esi=1 if msg.error_state_indicator else 0, dlc=len2dlc(msg.dlc), data_length=len(, data=" ".join(data), message_duration=0, message_length=0, flags=flags, crc=0, bit_timing_conf_arb=0, bit_timing_conf_data=0, bit_timing_conf_ext_arb=0, bit_timing_conf_ext_data=0, ) else: serialized = self.FORMAT_MESSAGE.format( channel=channel, id=arb_id, dir="Rx" if msg.is_rx else "Tx", dtype=dtype, data=" ".join(data), ) self.log_event(serialized, msg.timestamp)