Data Sources

Abstract base interface for vehicle data sources.

class openxc.sources.base.BytestreamDataSource(**kwargs)

A source that receives data is a series of bytes, with discrete messages separated by a newline character.

Subclasses of this class need only to implement the read method.

parse_messages()

run()

Continuously read data from the source and attempt to parse a valid message from the buffer of bytes. When a message is parsed, passes it off to the callback if one is set.

class openxc.sources.base.DataSource(callback=None, log_mode=None, payload_format=None)

Interface for all vehicle data sources. This inherits from Thread and when a source is added to a vehicle it attempts to call the start() method if it exists. If an implementer of DataSource needs some background process to read data, it’s just a matter of defining a run() method.

A data source requires a callback method to be specified. Whenever new data is received, it will pass it to that callback.

Construct a new DataSource.

By default, DataSource threads are marked as daemon threads, so they will die as soon as all other non-daemon threads in the process have quit.

Kwargs:

callback - function to call with any new data received

bytes_received

format

formatter

read(timeout=None)

Read data from the source.

Kwargs:

timeout (float) - if the source implementation could potentially

block, timeout after this number of seconds.

read_logs(timeout=None)

Read log data from the source.

Kwargs:

timeout (float) - if the source implementation could potentially

block, timeout after this number of seconds.

start()

Start the thread’s activity.

It must be called at most once per thread object. It arranges for the object’s run() method to be invoked in a separate thread of control.

This method will raise a RuntimeError if called more than once on the same thread object.

stop()

streamer

exception openxc.sources.base.DataSourceError

exception openxc.sources.base.MissingPayloadFormatError

class openxc.sources.base.SourceLogger(source, mode='off')

FILENAME_TEMPLATE = '%d-%m-%Y.%H-%M-%S'

record(message)

run()

Continuously read data from the source and attempt to parse a valid message from the buffer of bytes. When a message is parsed, passes it off to the callback if one is set.

stop()

A virtual serial port data source.

class openxc.sources.serial.SerialDataSource(port=None, baudrate=None, **kwargs)

A data source reading from a serial port, which could be implemented with a USB to Serial or Bluetooth adapter.

Initialize a connection to the serial device.

Kwargs:

port - optionally override the default virtual COM port baudrate - optionally override the default baudrate

Raises:

DataSourceError if the serial device cannot be opened.

DEFAULT_BAUDRATE = 230400

DEFAULT_PORT = '/dev/ttyUSB0'

read()

Read data from the source.

Kwargs:

timeout (float) - if the source implementation could potentially

block, timeout after this number of seconds.

A USB vehicle interface data source.

class openxc.sources.usb.UsbDataSource(vendor_id=None, product_id=None, **kwargs)

A source to receive data from an OpenXC vehicle interface via USB.

Initialize a connection to the USB device’s IN endpoint.

Kwargs:

vendor_id (str or int) - optionally override the USB device vendor

ID we will attempt to connect to, if not using the OpenXC hardware.

product_id (str or int) - optionally override the USB device product

ID we will attempt to connect to, if not using the OpenXC hardware.

log_mode - optionally record or print logs from the USB device, which

are on a separate channel.

Raises:

DataSourceError if the USB device with the given vendor ID is not connected.

DEFAULT_INTERFACE_NUMBER = 0

DEFAULT_PRODUCT_ID = 1

DEFAULT_READ_REQUEST_SIZE = 512

DEFAULT_READ_TIMEOUT = 200

DEFAULT_VENDOR_ID = 7108

LIBUSB0_TIMEOUT_CODE = -116

LIBUSB1_TIMEOUT_CODE = -7

LOG_IN_ENDPOINT = 11

OPENUSB_TIMEOUT_CODE = -62

VEHICLE_DATA_IN_ENDPOINT = 2

read(timeout=None)

Read data from the source.

Kwargs:

timeout (float) - if the source implementation could potentially

block, timeout after this number of seconds.

read_logs(timeout=None)

Read log data from the source.

Kwargs:

timeout (float) - if the source implementation could potentially

block, timeout after this number of seconds.

stop()

A data source for reading from pre-recorded OpenXC trace files.

class openxc.sources.trace.TraceDataSource(filename=None, realtime=True, loop=True, **kwargs)

A class to replay a previously recorded OpenXC vehicle data trace file. For details on the trace file format, see http://openxcplatform.com/android/testing.html.

Construct the source and attempt to open the trace file.

filename - the full absolute path to the trace file

realtime - if True, the trace will be replayed at approximately the same cadence as it was recorded. Otherwise, the trace file will be replayed as fast as possible (likely much faster than any vehicle).

loop - if True, the trace file will be looped and will provide data until the process exist or the source is stopped.

read()

Read a line of data from the input source at a time.

A network socket data source.

class openxc.sources.network.NetworkDataSource(host=None, port=None, **kwargs)

A data source reading from a network socket, as implemented in the openxc-vehicle-simulator .

Initialize a connection to the network socket.

Kwargs:

host - optionally override the default network host (default is local machine) port - optionally override the default network port (default is 50001) log_mode - optionally record or print logs from the network source

Raises:

DataSourceError if the socket connection cannot be opened.

DEFAULT_PORT = 50001