The can package provides controller area network support for Python developers

Brian Thorne

Last update: Dec 29, 2022

Related tags

Networking python can-bus

Overview

python-can

The Controller Area Network is a bus standard designed to allow microcontrollers and devices to communicate with each other. It has priority based bus arbitration and reliable deterministic communication. It is used in cars, trucks, boats, wheelchairs and more.

The can package provides controller area network support for Python developers; providing common abstractions to different hardware devices, and a suite of utilities for sending and receiving messages on a can bus.

The library currently supports Python 3.6+ as well as PyPy 3 and runs on Mac, Linux and Windows.

Library Version	Python
2.x	2.6+, 3.4+
3.x	2.7+, 3.5+
4.x (currently on develop)	3.6+

Features

common abstractions for CAN communication
support for many different backends (see the docs)
receiving, sending, and periodically sending messages
normal and extended arbitration IDs
CAN FD support
many different loggers and readers supporting playback: ASC (CANalyzer format), BLF (Binary Logging Format by Vector), CSV, SQLite and Canutils log
efficient in-kernel or in-hardware filtering of messages on supported interfaces
bus configuration reading from a file or from environment variables
command line tools for working with CAN buses (see the docs)
more

Example usage

# import the library
import can

# create a bus instance
# many other interfaces are supported as well (see below)
bus = can.Bus(interface='socketcan',
              channel='vcan0',
              receive_own_messages=True)

# send a message
message = can.Message(arbitration_id=123, is_extended_id=True,
                      data=[0x11, 0x22, 0x33])
bus.send(message, timeout=0.2)

# iterate over received messages
for msg in bus:
    print("{:X}: {}".format(msg.arbitration_id, msg.data))

# or use an asynchronous notifier
notifier = can.Notifier(bus, [can.Logger("recorded.log"), can.Printer()])

You can find more information in the documentation, online at python-can.readthedocs.org.

Discussion

If you run into bugs, you can file them in our issue tracker on GitHub.

There is also a python-can mailing list for development discussion.

Stackoverflow has several questions and answers tagged with python+can.

Wherever we interact, we strive to follow the Python Community Code of Conduct.

Contributing

See doc/development.rst for getting started.

Comments

Dropped CAN frames using Socketcan on Raspberry Pi

I'm using this library for logging data sent on a CAN-Bus running at 500 kbit/s. The data is sent roughly at 1 kHz.

I have set up a CAN Notifier to receive the data in a thread and the data is then written to a queue in a listener:

class LoggerBufferedListener(can.Listener):
    def __init__(self, log_opened_event: Event):
        self._log_opened_event = log_opened_event
        self._buffer = Queue()
        self._lock = Lock()
        self._closed = False

    def set_closed(self, closed):
        with self._lock:
            self._closed = closed

    def is_closed(self):
        with self._lock:
            return self._closed

    def on_message_received(self, msg: can.Message):
        # Only put the CAN-Bus message into the buffer if it is a close/open command or we are currently logging data
        # and the arbitration ID matches any of the logger IDs
        if msg.arbitration_id == CANLogger.ID_CLOSE_OPEN or \
                (self._log_opened_event.is_set() and
                 msg.arbitration_id in [logger['id'] for logger in CANLogger.Loggers]):
            self.put_nowait(msg)

    def get(self):
        return self._buffer.get()

    def get_nowait(self):
        try:
            return self._buffer.get_nowait()
        except queue.Empty:
            return None

    def put(self, item, force=False):
        if not force:
            if self.is_closed():
                return  # Return if the reader is closed

        self._buffer.put(item)

    def put_nowait(self, item):
        if self.is_closed():
            return  # Return if the reader is closed

        try:
            self._buffer.put_nowait(item)
        except queue.Full:
            Logger.exception('LoggerBufferedListener: Buffer is full')

Another thread is doing nothing else than calling the get() method, the messages are then unpacked and converted to SI-units similar to how I did it in the viewer program:

https://github.com/hardbyte/python-can/blob/9f6f9188ff4ad78b0162925781d24625ca65ac50/can/viewer.py#L135-L159

The data is then written to RAM. After the logged is closed the data is then stored in an Influx database.

However it seems that messages are dropped somewhere, as the data often has gaps in it.

I'm using a MCP2515 and have enabled it using the following overlays in /boot/config.txt:

dtoverlay=mcp2515-can0,oscillator=16000000,interrupt=12
dtoverlay=spi0-hw-cs

My question is basically if anyone has any experience using Socketcan on a Raspberry Pi. Do you guys believe it's a hardware or software issue? I've considered using a different CAN tranceiver than the MCP2515 just to check if that is the culprit. If that does not work I might try to implement the logging in C instead, but would prefer to use Python, as that makes all the parsing of data and writing to the database much easier.

opened by Lauszus 40

socketcan Exchanging data between 2 bus - Time limited

I am trying to exchange data between 2 bus - sending data from bus 1 to bus 2 - quit simple would you say? It all starts fine sending all message from bus 1 to bus 2 and the other way around, but then after about 500ms and 150 frames sent. The exchange stops....is there any reason why the code below would do so?

from multiprocessing import Process
import can

bus1 = can.interface.Bus(bustype='socketcan', channel='can0', bitrate=500000)
bus2 = can.interface.Bus(bustype='socketcan', channel='can2', bitrate=500000)
#

    
def loop_a():
    for msg in bus2:
            bus1.send(msg,timeout=None)


def loop_b():
    for msg in bus1:
            bus2.send(msg,timeout=None)

if __name__ == '__main__':
        Process(target=loop_a).start()
        Process(target=loop_b).start()

question minor

opened by Bobet21 37

Trc file support

With this i added basic support for the TRC file format as logging for can messages. There is only a very basic support at the moment but comments are welcome on what file versions might be relevant and if the basic code looks good

opened by pkess 32
Version bump CI tools

The automated static analysis tools are updated to their most recent version.

EDIT: I basically updated the tools in requirements-lint.txt and some images in Travis CI. Then I and re-ran the formatter, which causes much of the diff. I also removed the formatting job from Travis as it was already done by Github actions. I removed the normal testing from Travis, as it is much easier to specify in Github actions (and we now also test more platforms, like properly test on macOS!). We now also test on newer versions of Python as well (currently up to 3.10.0-alpha.4) and on Pypy on all platforms (also new).
enhancement QA

opened by felixdivo 26
Do you use python-can? Tell us!

This is not an issue so much as a lightweight way of gathering information on who is using python-can. This is mostly to satisfy our curiosity, but might also help us decide how to evolve the project.

So, if you use python-can, please post here and tell us more!
question

opened by hardbyte 26

Broken Install - PyPI Release 3.2.0

Related to #520

Looks like a similar issue has come up in the latest release?

$ sudo chroot /tmp/make_image.26839.root /usr/local/bin/pip2 install python-can evdev
Requirement already satisfied: python-can in /usr/local/lib/python2.7/dist-packages
Collecting evdev
  Using cached https://files.pythonhosted.org/packages/fe/6e/3fa84a43571dec4d00dc26befccc9867b6b3263651531cbc1345f718860f/evdev-1.2.0.tar.gz
Requirement already satisfied: typing in /usr/local/lib/python2.7/dist-packages (from python-can)
Collecting windows-curses (from python-can)
  Could not find a version that satisfies the requirement windows-curses (from python-can) (from versions: )
No matching distribution found for windows-curses (from python-can)
You are using pip version 9.0.1, however version 19.1.1 is available.
You should consider upgrading via the 'pip install --upgrade pip' command.

bug critical os:windows

opened by phil-marble 25

What to do in 2020 - Python 2 EOL

Being the last of the 2.x series, 2.7 will have an extended period of maintenance. Specifically, 2.7 will receive bugfix support until January 1, 2020. After the last release, 2.7 will receive no support.

It's no secret that Python 2 is reaching its end of life.

What do we do from then on? Should we just document which version was the last to support Python 2 + 3 and then do a (possibly incremental) cleanup of the code and only support Python 3 from then on? We could do that in a major version bump (like maybe 4.0).

I would vote for exactly that. Do we all agree on that?
question major

opened by felixdivo 25

Assertion error when trying to parse a legit CANoe generated BLF file

I'm trying to parse a BLF using this approach:

import can
from pprint import pprint as pp

filename = "logfile.blf"
logging = can.BLFReader(filename)
logging = list(logging)
pp(logging)

and get

Traceback (most recent call last):
  File "D:\eclipse-workspace\blf2csv\pythoncan_blf2csv.py", line 7, in <module>
    logging = list(logging)
  File "C:\Users\my_user_name\AppData\Local\Python\Python36\lib\site-packages\can\io\blf.py", line 129, in __iter__
    assert header[0] == b"LOBJ", "Parse error"
AssertionError: Parse error

The file is legit (I can convert it to CSV using Vector CANoe Tool >> Log File Conversion dialog (so I can convert a single file but looked at python-can as a means to do a batch conversion of multiple log files)).

bug

opened by z33kz33k 24

implemented FD for Pcan
I have implemented FD support for PCAN (solving #507). This code has been tested manually on PCAN-FD hardware.

Points to be discussed:

Parameters for the bit rate are passed as keyword args. Should this be switched to be a single string? (this is what the Pcan API accepts). The benefit to switching would be a simpler interface.

Messages with a non standard message size are padded right now with zeros. Should we allow for an option to configure the padding? What should the default padding be?

enhancement backend:pcan
opened by bmeisels 22
New location for scripts

This PR moved the scripts to a new location. For that, I had to change how pytest is configured to still include the scripts in the coverage data.

Preparation for Lauszus/python_can_viewer#2.
minor api docs testing

opened by felixdivo 22
Add interprocess virtual bus
This PR adds a virtual interface, that allows multiple processes to exchange can data. This is done by wrapping the CAN frames in IPv6/4 packets and sending them to a multicast group. The wrapping is done using MessagePack as proposed by @windelbouwman. That theoretically allows processes running other software than this one to interoperate with python-can, though I doubt it will used as that much. The TTL of the IP packets is set to one by default, disallowing the packet to escape the localhost. It is configurable however, and would allow the communicating processes to run on different machines as well. However this has not been tested.

Things to discuss before this can be merged:

[x] How shall it be called? virtual_interprocess, can_over_ip? Other suggestions? -> I would opt for can_over_ip.

[x] How does this relate to the current virtual interface? Is it a replacement, or an addition? In principle, it is at feature-rich as the current virtual interface, but might be a bit slower and requires an external library. I would suggest that it is a addition. Shall msgpack be added as a general required package? -> added to the required ones as it is tiny and does not have any transitive dependencies

[x] Do we want to provide the MessagePack wrapping of the CAN frames to other interfaces or the user as well? It might be useful beyond this interface at some point and is fairly general. -> Can still be done

Things for me to do

[x] implement receive_own_messages -> raise warning if used for now

[x] add tests

[x] add docs/examples

[x] register as an interface

Closes #530.
enhancement api backend:virtual os:linux os:macOS
opened by felixdivo 20
Functionalities of send_periodic()

Hello! Sorry if this has already been discussed somewhere else but: I need to send multiple periodic messages that also need to be modified in the long run, the trigger event is a user input in order to try and make test bench power up. In the docs I read:

The task will be active until one of the following conditions are met: - the (optional) duration expires - the Bus instance goes out of scope - the Bus instance is shutdown - :meth:stop_all_periodic_tasks is called - the task's :meth:~can.broadcastmanager.CyclicTask.stop method is called.

Also when i perform a send_periodic() a new task is returned, just a clarification: does the task need to stay on scope or is it the can.interface.Bus instance? Should I keep a dictionary { 'can0': { arb_id: taks } 'can1': { arb_id: taks } }

And simply update the task data at occurance?

opened by questberna 0
Update PCAN Basic to 4.6.2.753

@lumagi Since you have a PEAK device, could you check whether "channel": channel.device_name + str(channel.controller_number) is correct?

It is used in can.detect_available_configs("pcan")
backend:pcan

opened by zariiii9003 1
CI skips some of the SocketCAN unit tests
Describe the bug

The SocketCAN tests are only executed when the environment variable TEST_SOCKETCAN is present. The variable was likely introduced in the Travis CI environment and passed into test execution via tox. I noticed that it is no longer present in the current GitHub Workflow CI environment. This causes several of the SocketCAN tests to be skipped.

Updating the pipeline would include two things:

Executing test/open_vcan.sh on Linux machines

Adding the environment variable TEST_SOCKETCAN or removing it and simply executing these tests for all Linux systems

I know that workflow scripts have root permission on the GitHub runners. But I wasn't able to check if they also have capability NET_ADMIN to open vcan interfaces. Additionally, I wasn't sure if I could and didn't want to open a PR and mess with the workflow pipeline before opening an issue first. @zariiii9003 was the variable removed on purpose? If not, I can volunteer a patch, but I wanted to ask for some feedback first.
bug
opened by lumagi 9
Unify bit timings with separate class for CAN FD
This is a continuation of #614 and #615. I would like to hear your opinions before i waste my time on writing tests and docs.

I made the following changes:

Create a separate class for CANFD. In my opinion the bit timing requirements for CAN2.0 and CANFD are just too different to use the same class for both.

Validate bit timings in __init__ method

Add multiple constructors to avoid too many optional parameters. It is now possible to create an instance though BitTiming(**kwargs), BitTiming.from_registers(**kwargs) and BitTiming.from_sample_point(**kwargs)

The bit timing classes inherit from typing.Mapping. Now the user can call dict(timing) to get a dictionary of the bit timing parameters. This should make it easier to save the parameters to a config file.

Solve the configuration loading problems of #1460

Interface implementations should add a single parameter like timing: Union[BitTiming, BitTimingFd]. It would take precedence over other parameters and provide a simple API for the user. The docstring of the parameter should tell the users which values for f_clock are accepted.
enhancement api
opened by zariiii9003 4

Releases(v4.1.0)

v4.1.0(Nov 24, 2022)
Installation

Available on PyPi https://pypi.org/project/python-can/4.1.0/

pip install python-can==4.1.0

Changes

Breaking Changes

windows-curses was moved to optional dependencies (#1395). Use pip install python-can[viewer] if you are using the can.viewer script on Windows.

The attributes of can.interfaces.vector.VectorChannelConfig were renamed from camelCase to snake_case (#1422).

Features

IO

The canutils logger preserves message direction (#1244) and uses common interface names (e.g. can0) instead of just channel numbers (#1271).

The can.logger script accepts the -a, --append option to add new data to an existing log file (#1326, #1327, #1361). Currently only the blf-, canutils- and csv-formats are supported.

All CLI extra_args are passed to the bus, logger and player initialisation (#1366).

Initial support for TRC files (#1217)

Type Annotations

python-can now includes the py.typed marker to support type checking according to PEP 561 (#1344).

Interface Improvements

The gs_usb interface can be selected by device index instead of USB bus/address. Loopback frames are now correctly marked with the is_rx flag (#1270).

The PCAN interface can be selected by its device ID instead of just the channel name (#1346).

The PCAN Bus implementation supports auto bus-off reset (#1345).

SocketCAN: Make find_available_interfaces() find slcanX interfaces (#1369).

Vector: Add xlGetReceiveQueueLevel, xlGenerateSyncPulse and xlFlushReceiveQueue to xldriver (#1387).

Vector: Raise a CanInitializationError, if the CAN settings can not be applied according to the arguments of VectorBus.__init__ (#1426).

Ixxat bus now implements BusState api and detects errors (#1141)

Bug Fixes

Improve robustness of USB2CAN serial number detection (#1129).

Fix channel2int conversion (#1268, #1269).

Fix BLF timestamp conversion (#1266, #1273).

Fix timestamp handling in udp_multicast on macOS (#1275, #1278).

Fix failure to initiate the Neousys DLL (#1281).

Fix AttributeError in IscanError (#1292, #1293).

Add missing vector devices (#1296).

Fix error for DLC > 8 in ASCReader (#1299, #1301).

Set default mode for FileIOMessageWriter to wt instead of rt (#1303).

Fix conversion for port number from config file (#1309).

Fix fileno error on Windows (#1312, #1313, #1333).

Remove redundant writer.stop() call that throws error (#1316, #1317).

Detect and cast types of CLI extra_args (#1280, #1328).

Fix ASC/CANoe incompatibility due to timestamp format (#1315, #1362).

Fix MessageSync timings (#1372, #1374).

Fix file name for compressed files in SizedRotatingLogger (#1382, #1683).

Fix memory leak in neoVI bus where message_receipts grows with no limit (#1427).

Raise ValueError if gzip is used with incompatible log formats (#1429).

Allow restarting of transmission tasks for socketcan (#1440)

Miscellaneous

Allow ICSApiError to be pickled and un-pickled (#1341)

Sort interface names in CLI API to make documentation reproducible (#1342)

Exclude repository-configuration from git-archive (#1343)

Improve documentation (#1397, #1401, #1405, #1420, #1421, #1434)

Officially support Python 3.11 (#1423)

Migrate code coverage reporting from Codecov to Coveralls (#1430)

Migrate building docs and publishing releases to PyPi from Travis-CI to GitHub Actions (#1433)

Source code(tar.gz)
Source code(zip)
v4.1.0a2(Nov 18, 2022)

Source code(tar.gz)
Source code(zip)
4.1.0-alpha1(Nov 16, 2022)

Test of whether Github actions will upload to pypi
Source code(tar.gz)
Source code(zip)
4.1.0-alpha0(Nov 15, 2022)
What's Changed

Fix guaranteed crash when using usb2can by @felixdivo in https://github.com/hardbyte/python-can/pull/1249

Update history & contributors by @hardbyte in https://github.com/hardbyte/python-can/pull/1251

If parsed data has shortened, overwrite end of line with spaces by @simonkerscher in https://github.com/hardbyte/python-can/pull/1201

Pass flags instead of flags_t type for USB2CAN by @jacobian91 in https://github.com/hardbyte/python-can/pull/1252

[IO][ASC]: fix data length by @jazi007 in https://github.com/hardbyte/python-can/pull/1246

ASCReader bugfix by @zariiii9003 in https://github.com/hardbyte/python-can/pull/1257

[IO][canutils]: add direction support by @jazi007 in https://github.com/hardbyte/python-can/pull/1244

Fix BLF timestamp conversion by @zariiii9003 in https://github.com/hardbyte/python-can/pull/1273

Fix channel2int conversion by @zariiii9003 in https://github.com/hardbyte/python-can/pull/1269

Update the black formatter to stable release by @felixdivo in https://github.com/hardbyte/python-can/pull/1279

[IO][canutils]: use common CAN interface names in generated logfile by @hartkopp in https://github.com/hardbyte/python-can/pull/1271

%d format is for a number, not str by @pierreluctg in https://github.com/hardbyte/python-can/pull/1281

Fix AttributeError in IscanError by @zariiii9003 in https://github.com/hardbyte/python-can/pull/1293

add missing vector devices by @chrisoro in https://github.com/hardbyte/python-can/pull/1296

Fix timestamp handling in udp_multicast on macOS by @felixdivo in https://github.com/hardbyte/python-can/pull/1278

Test python 3.11 in CI by @zariiii9003 in https://github.com/hardbyte/python-can/pull/1302

Default mode for FileIOMessageWriter should be wt by @pierreluctg in https://github.com/hardbyte/python-can/pull/1303

Fix fileno error on Windows (robotell bus) by @gribera in https://github.com/hardbyte/python-can/pull/1313

Improve gs_usb usability and fix loopback frames by @chemicstry in https://github.com/hardbyte/python-can/pull/1270

Remove redundant writer.stop call that throws error by @j-c-cook in https://github.com/hardbyte/python-can/pull/1317

Clean up comment after !1302 by @felixdivo in https://github.com/hardbyte/python-can/pull/1322

ASCReader: Fix error for DLC > 8 by @zariiii9003 in https://github.com/hardbyte/python-can/pull/1301

Enhance can.logger to consider the append option by @j-c-cook in https://github.com/hardbyte/python-can/pull/1327

Fix fileno error on Windows (Serial bus) by @MattWoodhead in https://github.com/hardbyte/python-can/pull/1333

fix typing in add_listener and remove_listener by @tamenol in https://github.com/hardbyte/python-can/pull/1335

Allow ICSApiError to be pickled and un-pickled by @pierreluctg in https://github.com/hardbyte/python-can/pull/1341

Sort interface names, to make documentation reproducible by @umlaeute in https://github.com/hardbyte/python-can/pull/1342

Exclude repository-configuration from git-archive by @umlaeute in https://github.com/hardbyte/python-can/pull/1343

Add py.typed file and distribute it upon installation by @felixdivo in https://github.com/hardbyte/python-can/pull/1344

Add device_id parameter to PcanBus constructor by @lumagi in https://github.com/hardbyte/python-can/pull/1346

Detect types in _parse_additonal_config by @zariiii9003 in https://github.com/hardbyte/python-can/pull/1328

Finds USB2CAN Serial Number by USB Name by @melloa in https://github.com/hardbyte/python-can/pull/1129

Raise appropriate error message when append is not possible by @j-c-cook in https://github.com/hardbyte/python-can/pull/1361

Add file_size() function to FileIOMessageWriter by @zariiii9003 in https://github.com/hardbyte/python-can/pull/1367

Fix race condition in back2back_test for UDP multicast bus by @lumagi in https://github.com/hardbyte/python-can/pull/1349

Refactor for mypy friendly version checks by @zariiii9003 in https://github.com/hardbyte/python-can/pull/1371

Write 3 ms digits to ascii to resolve CANoe bug by @j-c-cook in https://github.com/hardbyte/python-can/pull/1362

Pass CLI extra_args to Logger initialisation by @zariiii9003 in https://github.com/hardbyte/python-can/pull/1366

Add Parameter for Enabling PCAN Auto Bus-Off Reset by @1atabey1 in https://github.com/hardbyte/python-can/pull/1345

fix: conversion for port number by @Thepowa753 in https://github.com/hardbyte/python-can/pull/1309

Replace socket.error with OSError by @zariiii9003 in https://github.com/hardbyte/python-can/pull/1373

Improve MessageSync timings by @zariiii9003 in https://github.com/hardbyte/python-can/pull/1374

Fix _default_name for compressed files by @j-c-cook in https://github.com/hardbyte/python-can/pull/1383

socketcan: Make find_available_interfaces() find slcanX interfaces by @msalau in https://github.com/hardbyte/python-can/pull/1369

Extend XL api wrapper by @zariiii9003 in https://github.com/hardbyte/python-can/pull/1387

Vector init refactor by @zariiii9003 in https://github.com/hardbyte/python-can/pull/1389

Test on vector virtual bus if XL API is available by @zariiii9003 in https://github.com/hardbyte/python-can/pull/1390

Provide meaningful error message for xlGetApplConfig error by @zariiii9003 in https://github.com/hardbyte/python-can/pull/1392

Pass file mode to compress function by @j-c-cook in https://github.com/hardbyte/python-can/pull/1384

Update BufferedReader.get_message docstring by @barbacbd in https://github.com/hardbyte/python-can/pull/1397

Move windows-curses dependency to an optional extra by @Hnasar in https://github.com/hardbyte/python-can/pull/1395

Test load_config() by @nertpinx in https://github.com/hardbyte/python-can/pull/1396

Modify file_size help doc string by @j-c-cook in https://github.com/hardbyte/python-can/pull/1401

Fix Sphinx warnings by @zariiii9003 in https://github.com/hardbyte/python-can/pull/1405

Explicitly set supported file formats by @zariiii9003 in https://github.com/hardbyte/python-can/pull/1406

setup.cfg: Use license_files instead of license_file by @nertpinx in https://github.com/hardbyte/python-can/pull/1408

Update github actions by @zariiii9003 in https://github.com/hardbyte/python-can/pull/1409

Improve vector documentation by @zariiii9003 in https://github.com/hardbyte/python-can/pull/1420

Update docs and examples by @zariiii9003 in https://github.com/hardbyte/python-can/pull/1421

Add bus_params and use snake case for VectorChannelConfig by @zariiii9003 in https://github.com/hardbyte/python-can/pull/1422

Add python 3.11 to supported versions by @zariiii9003 in https://github.com/hardbyte/python-can/pull/1423

Fix #1376 by @zariiii9003 in https://github.com/hardbyte/python-can/pull/1412

Fix 1424 by @zariiii9003 in https://github.com/hardbyte/python-can/pull/1425

VectorBus: check whether CAN settings were correctly applied by @zariiii9003 in https://github.com/hardbyte/python-can/pull/1426

Fixing memory leak in neoVI bus where message_receipts grows with no limit by @pierreluctg in https://github.com/hardbyte/python-can/pull/1427

Add gzip check to compress method by @j-c-cook in https://github.com/hardbyte/python-can/pull/1429

Update CHANGELOG for v4.1.0 release by @zariiii9003 in https://github.com/hardbyte/python-can/pull/1363

Ixxat bus state and hardware errors detection by @cowo78 in https://github.com/hardbyte/python-can/pull/1141

Switch from codecov to coveralls by @hardbyte in https://github.com/hardbyte/python-can/pull/1430

Trc file support by @pkess in https://github.com/hardbyte/python-can/pull/1217

Source code(tar.gz)
Source code(zip)
4.0.0(Feb 19, 2022)
TL;DR: This release includes a ton of improvements from 2.5 years of development! 🎉 Test thoroughly after switching.

For more than two years, there was no major release of python-can. However, development was very much active over most of this time, and many parts were switched out and improved. Over this time, over 530 issues and PRs have been resolved or merged, and discussions took place in even more. Statistics of the final diff: About 200 files changed due to ~22k additions and ~7k deletions from more than thirty contributors.

This changelog diligently lists the major changes but does not promise to be the complete list of changes. Therefore, users are strongly advised to thoroughly test their programs against this new version. Re-reading the documentation for your interfaces might be helpful too as limitations and capabilities might have changed or are more explicit. While we did try to avoid breaking changes, in some cases it was not feasible and in particular, many implementation details have changed.

A massive thank you to Felix Divo for preparing this release, and to the many many contributors.

Major features

Type hints for the core library and some interfaces (#652 and many others)

Support for Python 3.7-3.10+ only (dropped support for Python 2.* and 3.5-3.6) (#528 and many others)

Granular and unified exceptions (#356, #562, #1025; overview in #1046)

Support for automatic configuration detection in most interfaces (#303, #640, #641, #811, #1077, #1085)

Better alignment of interfaces and IO to common conventions and semantics

New interfaces

udp_multicast (#644)

robotell (#731)

cantact (#853)

gs_usb (#905)

nixnet (#968, #1154)

neousys (#980, #1076)

socketcand (#1140)

etas (#1144)

Improved interfaces

socketcan

Support for multiple Cyclic Messages in Tasks (#610)

Socketcan crash when attempting to stop CyclicSendTask with same arbitration ID (#605, #638, #720)

Relax restriction of arbitration ID uniqueness for CyclicSendTask (#721, #785, #930)

Add nanosecond resolution time stamping to socketcan (#938, #1015)

Add support for changing the loopback flag (#960)

Socketcan timestamps are missing sub-second precision (#1021, #1029)

Add parameter to ignore CAN error frames (#1128)

socketcan_ctypes

Removed and replaced by socketcan after deprecation period

socketcan_native

Removed and replaced by socketcan after deprecation period

vector

Add chip state API (#635)

Add methods to handle non message events (#708)

Implement XLbusParams (#718)

Add support for VN8900 xlGetChannelTime function (#732, #733)

Add vector hardware config popup (#774)

Fix Vector CANlib treatment of empty app name (#796, #814)

Make VectorError pickleable (#848)

Add methods get_application_config(), set_application_config() and set_timer_rate() to VectorBus (#849)

Interface arguments are now lowercase (#858)

Fix errors using multiple Vector devices (#898, #971, #977)

Add more interface information to channel config (#917)

Improve timestamp accuracy on Windows (#934, #936)

Fix error with VN8900 (#1184)

Add static typing (#1229)

PCAN

Do not incorrectly reset CANMsg.MSGTYPE on remote frame (#659, #681)

Add support for error frames (#711)

Added keycheck for windows platform for better error message (#724)

Added status_string method to return simple status strings (#725)

Fix timestamp timezone offset (#777, #778)

Add Cygwin support (#840)

Update PCAN basic Python file to February 7, 2020 (#929)

Fix compatibility with the latest macOS SDK (#947, #948, #957, #976)

Allow numerical channel specifier (#981, #982)

macOS: Try to find libPCBUSB.dylib before loading it (#983, #984)

Disable command PCAN_ALLOW_ERROR_FRAMES on macOS (#985)

Force english error messages (#986, #993, #994)

Add set/get device number (#987)

Timestamps are silently incorrect on Windows without uptime installed (#1053, #1093)

Implement check for minimum version of pcan library (#1065, #1188)

Handle case where uptime is imported successfully but returns None (#1102, #1103)

slcan

Fix bitrate setting (#691)

Fix fileno crash on Windows (#924)

ics_neovi

Filter out Tx error messages (#854)

Adding support for send timeout (#855)

Raising more precise API error when set bitrate fails (#865)

Avoid flooding the logger with many errors when they are the same (#1125)

Omit the transmit exception cause for brevity (#1086)

Raise ValueError if message data is over max frame length (#1177, #1181)

Setting is_error_frame message property (#1189)

ixxat

Raise exception on busoff in recv() (#856)

Add support for 666 kbit/s bitrate (#911)

Add function to list hwids of available devices (#926)

Add CAN FD support (#1119)

seeed

Fix fileno crash on Windows (#902)

kvaser

Improve timestamp accuracy on Windows (#934, #936)

usb2can

Fix "Error 8" on Windows and provide better error messages (#989)

serial

Fix "TypeError: cannot unpack non-iterable NoneType" and more robust error handling (#1000, #1010)

canalystii

Fix is_extended_id (#1006)

Fix transmitting onto a busy bus (#1114)

Replace binary library with python driver (#726, #1127)

Other API changes and improvements

CAN FD frame support is pretty complete (#963)

ASCWriter (#604) and ASCReader (#741)

Canutils reader and writer (#1042)

Logger, viewer and player tools can handle CAN FD (#632)

Many bugfixes and more testing coverage

IO

Log rotation (#648, #874, #881, #1147)

Transparent (de)compression of gzip files for all formats (#1221)

Add plugin support to can.io Reader/Writer (#783)

ASCReader/Writer enhancements like increased robustness (#820, #1223)

Adding absolute timestamps to ASC reader (#761)

Support other base number (radix) at ASCReader (#764)

Add logconvert script (#1072, #1194)

Adding support for gzipped ASC logging file (.asc.gz) (#1138)

Improve IO class hierarchy (#1147)

An overview over various "virtual" interfaces (#644)

Make ThreadBasedCyclicSendTask event based & improve timing accuracy (#656)

Ignore error frames in can.player by default, add --error-frames option (#690)

Add an error callback to ThreadBasedCyclicSendTask (#743, #781)

Add direction to CAN messages (#773, #779, #780, #852, #966)

Notifier no longer raises handled exceptions in rx_thread (#775, #789) but does so if no listener handles them (#1039, #1040)

Changes to serial device number decoding (#869)

Add a default fileno function to the BusABC (#877)

Disallow Messages to simultaneously be "FD" and "remote" (#1049)

Speed up interface plugin imports by avoiding pkg_resources (#1110)

Allowing for extra config arguments in can.logger (#1142, #1170)

Add changed byte highlighting to viewer.py (#1159)

Change DLC to DL in Message.__str__() (#1212)

Other Bugfixes

BLF PDU padding (#459)

stop_all_periodic_tasks skipping every other task (#634, #637, #645)

Preserve capitalization when reading config files (#702, #1062)

ASCReader: Skip J1939Tp messages (#701)

Fix crash in Canutils Log Reader when parsing RTR frames (#713)

Various problems with the installation of the library

ASCWriter: Fix date format to show correct day of month (#754)

Fixes that some BLF files can't be read ( #763, #765)

Seek for start of object instead of calculating it (#786, #803, #806)

Only import winreg when on Windows (#800, #802)

Find the correct Reader/Writer independently of the file extension case (#895)

RecursionError when unpickling message object (#804, #885, #904)

Move "filelock" to neovi dependencies (#943)

Bus() with "fd" parameter as type bool always resolved to fd-enabled configuration (#954, #956)

Asyncio code hits error due to deprecated loop parameter (#1005, #1013)

Catch time before 1970 in ASCReader (#1034)

Fix a bug where error handlers were not called correctly (#1116)

Improved user interface of viewer script (#1118)

Correct app_name argument in logger (#1151)

Calling stop_all_periodic_tasks() in BusABC.shutdown() and all interfaces call it on shutdown (#1174)

Timing configurations do not allow int (#1175)

Some smaller bugfixes are not listed here since the problems were never part of a proper release

Behind the scenes & Quality assurance

We publish both source distributions (sdist) and binary wheels (bdist_wheel) (#1059, #1071)

Many interfaces were partly rewritten to modernize the code or to better handle errors

Performance improvements

Dependencies have changed

Derive type information in Sphinx docs directly from type hints (#654)

Better documentation in many, many places; This includes the examples, README and python-can developer resources

Add issue templates (#1008, #1017, #1018, #1178)

Many continuous integration (CI) discussions & improvements (for example: #951, #940, #1032)

Use the mypy static type checker (#598, #651)

Use tox for testing (#582, #833, #870)

Use Mergify (#821, #835, #937)

Switch between various CI providers, abandoned AppVeyor (#1009) and partly Travis CI, ended up with mostly GitHub Actions (#827, #1224)

Use the black auto-formatter (#950)

Good test coverage for all but the interfaces

Testing: Many of the new features directly added tests, and coverage of existing code was improved too (for example: #1031, #581, #585, #586, #942, #1196, #1198)

Source code(tar.gz)
Source code(zip)
python_can-4.0.0-py3-none-any.whl(230.31 KB)
python_can-4.0.0-py3-none-any.whl.asc(833 bytes)
python_can-4.0.0-py3.7.egg(510.93 KB)
python_can-4.0.0-py3.8.egg(513.77 KB)
python_can-4.0.0-py3.9.egg(513.54 KB)
4.0.0rc0(Feb 4, 2022)

This is the first release candidate for version 4.0.0. It includes a ton of improvements from 2.5 years of development! :tada:

Test thoroughly after switching and please report any issues that you experience while testing this pre-release.

Also, have a look at the complete CHANGELOG.

The documentation of the develop branch can be viewed here.
Source code(tar.gz)
Source code(zip)
4.0.0-dev.2(Apr 23, 2021)

Development release of python-can 4.0.0.
Source code(tar.gz)
Source code(zip)
4.0.0-dev.1(Apr 20, 2021)

Development release of python-can 4.0.0.

Note: This was not released to PyPI.
Source code(tar.gz)
Source code(zip)
3.3.5-dev.0(Oct 11, 2020)

Test release to fix https://github.com/hardbyte/python-can/issues/520
Source code(tar.gz)
Source code(zip)
3.3.4(Oct 4, 2020)
Last planned release with Python2 support! :fireworks:

#916 Vector: Skip channels without CAN support

#846 Use inter-process mutex to prevent concurrent neoVI device open.

#901 Fix iteration in Bus.stop_all_periodic_tasks

#850 Fix socket.error is a deprecated alias of OSError used on Python versions lower than 3.3.

#879 Updating incorrect api documentation.

#885 Fix recursion message in Message.getattr

#845 Fix socketcan issue

Source code(tar.gz)
Source code(zip)
3.3.4-beta.0(Aug 6, 2020)
Last call for Python2 support.

#850 Fix socket.error is a deprecated alias of OSError used on Python versions lower than 3.3.

#846 Use inter-process mutex to prevent concurrent neoVI device open.

#879 Updating incorrect api documentation.

#885 Fix recursion message in Message.getattr

#845 Fix socketcan issue

Source code(tar.gz)
Source code(zip)
4.0.0-dev.0(Jul 16, 2020)

Development release of python-can 4.0.0.
Source code(tar.gz)
Source code(zip)
3.3.3(May 22, 2020)
Backported fixes from 4.x development branch which targets Python 3.

#798 Backport caching msg.data value in neovi interface.

#796 Fix Vector CANlib treatment of empty app name.

#771 Handle empty CSV file.

#741 ASCII reader can now handle FD frames.

#740 Exclude test packages from distribution.

#713 RTR crash fix in canutils log reader parsing RTR frames.

#701 Skip J1939 messages in ASC Reader.

#690 Exposes a configuration option to allow the CAN message player to send error frames (and sets the default to not send error frames).

#638 Fixes the semantics provided by periodic tasks in SocketCAN interface.

#628 Avoid padding CAN_FD_MESSAGE_64 objects to 4 bytes.

#617 Fixes the broken CANalyst-II interface.

#605 Socketcan BCM status fix.

Note you will need setuptools version 36.2.2 or later.
Source code(tar.gz)
Source code(zip)
3.3.3-alpha.3(May 6, 2020)

Source code(tar.gz)
Source code(zip)
3.3.3-alpha.2(Apr 21, 2020)

Source code(tar.gz)
Source code(zip)
3.3.3-alpha.1(Apr 19, 2020)

Source code(tar.gz)
Source code(zip)
3.3.3-alpha.0(Apr 19, 2020)
Backported fixes from Python 3 only 4.x development.

Exclude test packages from distribution. #740

RTR crash fix in canutils log reader parsing RTR frames. #713

Skip J1939 messages in ASC Reader. #701

Exposes a configuration option to allow the CAN message player to send error frames (and sets the default to not send error frames). #690

Fixes the semantics provided by periodic tasks in SocketCAN interface. #638

Avoid padding CAN_FD_MESSAGE_64 objects to 4 bytes. #628

Fixes the broken CANalyst-II interface. #617

Socketcan BCM status fix. #605

Source code(tar.gz)
Source code(zip)
3.3.2.final(Sep 10, 2019)

Minor bug fix release addressing issue in PCAN RTR.

Released with tag pointing at correct commit this time.
Source code(tar.gz)
Source code(zip)
3.3.2(Aug 17, 2019)

This release was unfortunately pointing at the wrong commit.
Source code(tar.gz)
Source code(zip)
3.3.1(Jul 24, 2019)

Minor fix to setup.py to only require pytest-runner when necessary.
Source code(tar.gz)
Source code(zip)
3.3.0(Jun 27, 2019)
Adding CAN FD 64 frame support to blf reader

Updates to installation instructions

Clean up bits generator in PCAN interface #588

Minor fix to use latest tools when building wheels on travis.

Source code(tar.gz)
Source code(zip)
3.2.1(May 17, 2019)
CAN FD 64 frame support to blf reader

Minor fix to use latest tools when building wheels on travis.

Updates links in documentation.

Source code(tar.gz)
Source code(zip)
3.2.0(May 16, 2019)
Major features

FD support added for Pcan by @bmeisels with input from @markuspi, @christiansandberg & @felixdivo in PR #537

Other notable changes

#532 Support has been removed for Python 3.4

#533 BusState is now an enum.

#535 This release should automatically be published to PyPi by travis.

#577 Travis-ci now uses stages instead of matrix build.

#548 A guide has been added for new io formats.

#550 Finish moving from nose to pytest.

#558 Fix installation on Windows.

#561 Tests for MessageSync added.

General fixes, cleanup and docs changes can be found here.

Pulls: #522, #526, #527, #536, #540, #546, #547, #548, #533, #559, #569, #571, #572, #575

Backend Specific Changes

pcan

FD support in PR #537

slcan

ability to set custom can speed instead of using predefined speed values. #553

socketcan

Bug fix to properly support 32bit systems. #573

usb2can

slightly better error handling

multiple serial devices can be found

support for the _detect_available_configs() API

Pulls #511, #535

vector

handle app_name. #525

Source code(tar.gz)
Source code(zip)
3.2.0-beta.0(May 12, 2019)
Major features

FD support added for Pcan by @bmeisels with input from @markupspi, @christiansandberg & @felixdivo in PR #537

Other notable changes

#532 Support has been removed for Python 3.4

#533 BusState is now an enum.

#535 This release should automatically be published to PyPi by travis.

#577 Travis-ci now uses stages instead of matrix build.

#548 A guide has been added for new io formats.

#550 Finish moving from nose to pytest.

#558 Fix installation on Windows.

#561 Tests for MessageSync added.

General fixes, cleanup and docs changes can be found here.

Pulls: #522, #526, #527, #536, #540, #546, #547, #548, #533, #559, #569, #571, #572, #575

Backend Specific Changes

pcan

FD support in PR #537

slcan

ability to set custom can speed instead of using predefined speed values. #553

socketcan

Bug fix to properly support 32bit systems. #573

usb2can

slightly better error handling

multiple serial devices can be found

support for the _detect_available_configs() API

Pulls #511, #535

vector

handle app_name. #525

Source code(tar.gz)
Source code(zip)
3.1.1(Feb 25, 2019)

Same as 3.1.0 but built with Python 3.7 and up dated setuptools, wheel etc
Source code(tar.gz)
Source code(zip)
v3.1.0(Feb 24, 2019)
Major features

Two new interfaces this release:

SYSTEC contributed by @idaniel86 in PR #466

CANalyst-II contributed by @smeng9 in PR #476

Other notable changes

#477 The kvaser interface now supports bus statistics via a custom bus method.

#434 neovi now supports receiving own messages

#490 Adding option to override the neovi library name

#488 Allow simultaneous access to IXXAT cards

#447 Improvements to serial interface:

to allow receiving partial messages

to fix issue with DLC of remote frames

addition of unit tests

#497 Small API changes to Message and added unit tests

#471 Fix CAN FD issue in kvaser interface

#462 Fix Notifier issue with asyncio

#481 Fix PCAN support on OSX

#455 Fix to Message initializer

Small bugfixes and improvements

Source code(tar.gz)
Source code(zip)
python-can-3.1.0.tar.gz(154.51 KB)
python-can-3.1.0.tar.gz.asc(833 bytes)
python_can-3.1.0-py2.py3-none-any.whl(149.05 KB)
python_can-3.1.0-py2.py3-none-any.whl.asc(833 bytes)
3.1.0-rc1(Jan 7, 2019)
New Interfaces

SYSTEC contributed by @idaniel86 in PR #466

CANalyst-II contributed by @smeng9 in PR #476

New Features

#477 kvaser interface now supports bus statistics via a custom bus method.

#471 fix CAN FD issue in kvaser interface

#434 neovi supports receiving own messages

#447 improvements to serial interface:

to allow receiving partial messages

to fix issue with DLC of remote frames

addition of unit tests

#462 Notifier issue with asyncio.

#481 - Fix PCAN support on OSX.

#455 minor fix to Message initializer.

See all the merged pull requests here.
Source code(tar.gz)
Source code(zip)
3.0.0(Oct 4, 2018)
Major features

Adds support for developing asyncio applications with python-can more easily. This can be useful when implementing protocols that handles simultaneous connections to many nodes since you can write synchronous looking code without handling multiple threads and locking mechanisms. #388

New can viewer terminal application. #390

More formally adds task management responsibility to the Bus. By default tasks created with bus.send_periodic will have a reference held by the bus - this means in many cases the user doesn't need to keep the task in scope for their periodic messages to continue being sent. If this behavior isn't desired pass store_task=False to the send_periodic method. Stop all tasks by calling the bus's new stop_all_periodic_tasks method. #412

Breaking changes

Interfaces should no longer override send_periodic and instead implement _send_periodic_internal #426

writing to closed writers is not supported any more (it was supported only for some)

the method Listener.on_message_received() is now abstract (using @abc.abstractmethod)

the file in the reader/writer is now always stored in the attribute uniformly called file, and not in something like fp, log_file or output_file. Changed the name of the first parameter of the read/writer constructors from filename to file.

Backend Specific Changes

3rd party interfaces

Deprecated python_can.interface entry point instead use can.interface. #389

neovi

Added support for CAN-FD #408

Fix issues checking if bus is open. #381

Adding multiple channels support. #415

nican

implements reset instead of custom flush_tx_buffer. #364

pcan

now supported on OSX. #365

serial

Removed TextIOWrapper from serial. #383

switch to serial_for_url enabling using remote ports via loop://, ``socket://andrfc2217://` URLs. #393

hardware handshake using rtscts kwarg #402

socketcan

socketcan tasks now reuse a bcm socket

socketcan bugfix to receive error frames #384

vector

Vector interface now implements _detect_available_configs. #362

Added support to select device by serial number. #387

Other notable changes

can.Message class updated #413

Addition of a Message.equals method.

Deprecate id_type in favor of is_extended_id

documentation, testing and example updates

Addition of support for various builtins: repr, slots, copy

IO module updates to bring consistency to the different CAN message writers and readers. #348

context manager support for all readers and writers

they share a common super class called BaseIOHandler

all file handles can now be closed with the stop() method

the table name in SqliteReader/SqliteWriter can be adjusted

append mode added in CSVWriter and CanutilsLogWriter

file-like and path-like objects can now be passed to the readers and writers (except to the Sqlite handlers)

add a __ne__() method to the Message class (this was required by the tests)

added a stop() method for BufferedReader

SqliteWriter: this now guarantees that all messages are being written, exposes some previously internal metrics and only buffers messages up to a certain limit before writing/committing to the database.

the unused header_line attribute from CSVReader has been removed

privatized some attributes that are only to be used internally in the classes

Start testing against Python 3.7 #380

All scripts have been moved into can/scripts. #370, #406

Added support for additional sections to the config #338

Code coverage reports added. #346, #374

Bug fix to thread safe bus. #397

General fixes, cleanup and docs changes: (#347, #348, #367, #368, #370, #371, #373, #420, #417, #419)

Documentation: https://python-can.readthedocs.io/en/3.0.0/

Installation

pip install python-can==3.0.0
Source code(tar.gz)
Source code(zip)
python-can-3.0.0.tar.gz(126.61 KB)
python_can-3.0.0-py2.py3-none-any.whl(120.74 KB)
2.2.1(Jul 12, 2018)
Bug fixes

Fix errors and warnings when importing library on Windows

Fix Vector backend raising ValueError when hardware is not connected

Installation

Get it from PyPi:

pip install -U python-can==2.2.1
Source code(tar.gz)
Source code(zip)
python-can-2.2.1.tar.gz(112.79 KB)
python_can-2.2.1-py2.py3-none-any.whl(133.75 KB)
2.2.0(Jul 3, 2018)
Major Features

Fallback message filtering implemented in Python for interfaces that don't offer better accelerated mechanism. #157, #277, #104

SocketCAN interfaces have been merged (socketcan_native and socketcan_ctypes), this is now completely transparent for the library user. #326

automatic detection of available configs/channels in supported interfaces (see #303)

Added synchronized (thread-safe) Bus variant. #315

context manager support for the Bus class. #283

added CSVReader. Improved testing of CSVReader/CSVWriter #270

Notifier supports multiple buses #332

Removals

Dropped support for Python 3.3 (officially reached end-of-life in Sept. 2017)

Deprecated the old CAN module, please use the newer can entry point (will be removed in version 2.4). #267

Interface Specific Changes

There were many changes and a lot of cleanup effort in the individual interfaces. Some of the highlights:

SocketCAN

Use socketcan in the future instead of socketcan_native or socketcan_ctypes

Cyclic improvements #323

Fix version selection. #293

Low level fixes. #296

VectorCAN

CAN FD support #311

Fix bug where messages were sent to only one virtual channel #302

Various fixes in #258:

Avoid polling by using Win32 events when possible

Support for receive_own_messages argument

PCAN

Use configured bitrate. #254

USB2CAN

Show stopping bug #219 has been fixed.

Minor Changes

Minor api change to the can.Notifier adding add_listener and remove_listener methods #266

SqlReader and SqlWriter have been renamed to SqliteReader and SqliteWriter. #263

readers/writers now support error frames correctly. #217, #247, #256

bug fixes

a lot of (CI) testing effort. #342

improved documentation

code cleanup. #309

Installation

Get it from PyPi:

pip install -U python-can==2.2.0
Source code(tar.gz)
Source code(zip)
python-can-2.2.0.tar.gz(101.70 KB)
python_can-2.2.0-py2.py3-none-any.whl(101.57 KB)