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.

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()
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()

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
LOG_IN_ENDPOINT = 11
VEHICLE_DATA_IN_ENDPOINT = 2
read(timeout=None)
read_logs(timeout=None)
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