Source code for

# coding: utf-8

This module contains handling for CSV (comma seperated values) files.

TODO: CAN FD messages are not yet supported.

TODO: This module could use
      to allow different delimiters for writing, special escape chars to circumvent
      the base64 encoding and use csv.Sniffer to automatically deduce the delimiters
      of a CSV file.

from __future__ import absolute_import

from base64 import b64encode, b64decode

from can.message import Message
from can.listener import Listener
from .generic import BaseIOHandler

[docs]class CSVWriter(BaseIOHandler, Listener): """Writes a comma separated text file with a line for each message. Includes a header line. The columns are as follows: ================ ======================= =============== name of column format description example ================ ======================= =============== timestamp decimal float 1483389946.197 arbitration_id hex 0x00dadada extended 1 == True, 0 == False 1 remote 1 == True, 0 == False 0 error 1 == True, 0 == False 0 dlc int 6 data base64 encoded WzQyLCA5XQ== ================ ======================= =============== Each line is terminated with a platform specific line seperator. """ def __init__(self, file, append=False): """ :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 bool append: if set to `True` messages are appended to the file and no header line is written, else the file is truncated and starts with a newly written header line """ mode = 'a' if append else 'w' super(CSVWriter, self).__init__(file, mode=mode) # Write a header row if not append: self.file.write("timestamp,arbitration_id,extended,remote,error,dlc,data\n")
[docs] def on_message_received(self, msg): row = ','.join([ repr(msg.timestamp), # cannot use str() here because that is rounding hex(msg.arbitration_id), '1' if msg.is_extended_id else '0', '1' if msg.is_remote_frame else '0', '1' if msg.is_error_frame else '0', str(msg.dlc), b64encode('utf8') ]) self.file.write(row) self.file.write('\n')
[docs]class CSVReader(BaseIOHandler): """Iterator over CAN messages from a .csv file that was generated by :class:`~can.CSVWriter` or that uses the same format as described there. Assumes that there is a header and thus skips the first line. Any line seperator is accepted. """ def __init__(self, file): """ :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. """ super(CSVReader, self).__init__(file, mode='r') def __iter__(self): # skip the header line next(self.file) for line in self.file: timestamp, arbitration_id, extended, remote, error, dlc, data = line.split(',') yield Message( timestamp=float(timestamp), is_remote_frame=(remote == '1'), extended_id=(extended == '1'), is_error_frame=(error == '1'), arbitration_id=int(arbitration_id, base=16), dlc=int(dlc), data=b64decode(data), ) self.stop()