Library API

The main objects are the BusABC and the Message. A form of CAN interface is also required.

Hint

Check the backend specific documentation for any implementation specific details.

Utilities

Utilities and configuration file parsing.

can.util.choose_socketcan_implementation()[source]

Set the best version of SocketCAN for this system.

Parameters:config – The can.rc configuration dictionary
Raises:Exception – If the system doesn’t support SocketCAN
can.util.load_config(path=None, config=None)[source]

Returns a dict with configuration details which is loaded from (in this order):

  • config
  • can.rc
  • Environment variables CAN_INTERFACE, CAN_CHANNEL
  • Config files /etc/can.conf or ~/.can or ~/.canrc where the latter may add or replace values of the former.

Interface can be any of the strings from can.VALID_INTERFACES for example: kvaser, socketcan, pcan, usb2can, ixxat, nican, remote, virtual.

Note

If you pass "socketcan" this automatically selects between the native and ctypes version.

Parameters:
  • path – Optional path to config file.
  • config – A dict which may set the ‘interface’, and/or the ‘channel’, or neither.
Returns:

A config dictionary that should contain ‘interface’ & ‘channel’:

{
    'interface': 'python-can backend interface to use',
    'channel': 'default channel to use',
}

Note None will be used if all the options are exhausted without finding a value.

can.util.load_environment_config()[source]

Loads config dict from environmental variables (if set):

  • CAN_INTERFACE
  • CAN_CHANNEL
can.util.load_file_config(path=None)[source]

Loads configuration from file with following content:

[default]
interface = socketcan
channel = can0
Parameters:path – path to config file. If not specified, several sensible default locations are tried depending on platform.
can.util.set_logging_level(level_name=None)[source]

Set the logging level for the “can” logger. Expects one of: ‘critical’, ‘error’, ‘warning’, ‘info’, ‘debug’, ‘subdebug’

Notifier

The Notifier object is used as a message distributor for a bus.

class can.Notifier(bus, listeners, timeout=None)[source]

Bases: object

Manages the distribution of Messages from a given bus to a list of listeners.

Parameters:
  • bus – The Bus to listen too.
  • listeners – An iterable of Listeners
  • timeout – An optional maximum number of seconds to wait for any message.
exception = None

Exception raised in thread

stop()[source]

Stop notifying Listeners when new Message objects arrive and call stop() on each Listener.