sensor.leap

class platypush.backend.sensor.leap.LeapFuture(seconds, listener, event)[source]
__init__(seconds, listener, event)[source]

This constructor should always be called with keyword arguments. Arguments are:

group should be None; reserved for future extension when a ThreadGroup class is implemented.

target is the callable object to be invoked by the run() method. Defaults to None, meaning nothing is called.

name is the thread name. By default, a unique name is constructed of the form “Thread-N” where N is a small decimal number.

args is the argument tuple for the target invocation. Defaults to ().

kwargs is a dictionary of keyword arguments for the target invocation. Defaults to {}.

If a subclass overrides the constructor, it must make sure to invoke the base class constructor (Thread.__init__()) before doing anything else to the thread.

cancel()

Stop the timer if it hasn’t finished yet.

property daemon

A boolean value indicating whether this thread is a daemon thread.

This must be set before start() is called, otherwise RuntimeError is raised. Its initial value is inherited from the creating thread; the main thread is not a daemon thread and therefore all threads created in the main thread default to daemon = False.

The entire Python program exits when only daemon threads are left.

property ident

Thread identifier of this thread or None if it has not been started.

This is a nonzero integer. See the get_ident() function. Thread identifiers may be recycled when a thread exits and another thread is created. The identifier is available even after the thread has exited.

is_alive()

Return whether the thread is alive.

This method returns True just before the run() method starts until just after the run() method terminates. See also the module function enumerate().

join(timeout=None)

Wait until the thread terminates.

This blocks the calling thread until the thread whose join() method is called terminates – either normally or through an unhandled exception or until the optional timeout occurs.

When the timeout argument is present and not None, it should be a floating point number specifying a timeout for the operation in seconds (or fractions thereof). As join() always returns None, you must call is_alive() after join() to decide whether a timeout happened – if the thread is still alive, the join() call timed out.

When the timeout argument is not present or None, the operation will block until the thread terminates.

A thread can be join()ed many times.

join() raises a RuntimeError if an attempt is made to join the current thread as that would cause a deadlock. It is also an error to join() a thread before it has been started and attempts to do so raises the same exception.

property name

A string used for identification purposes only.

It has no semantics. Multiple threads may be given the same name. The initial name is set by the constructor.

property native_id

Native integral thread ID of this thread, or None if it has not been started.

This is a non-negative integer. See the get_native_id() function. This represents the Thread ID as reported by the kernel.

run()

Method representing the thread’s activity.

You may override this method in a subclass. The standard run() method invokes the callable object passed to the object’s constructor as the target argument, if any, with sequential and keyword arguments taken from the args and kwargs arguments, respectively.

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.

class platypush.backend.sensor.leap.LeapListener(*args: Any, **kwargs: Any)[source]
__init__(position_ranges, position_tolerance, logger, frames_throttle_secs=None)[source]
class platypush.backend.sensor.leap.SensorLeapBackend(position_ranges=None, position_tolerance=0.0, frames_throttle_secs=None, *args, **kwargs)[source]

Backend for events generated using a Leap Motion device to track hands and gestures, https://www.leapmotion.com/

Note that the default SDK is not compatible with Python 3. Follow the instructions on https://github.com/BlackLight/leap-sdk-python3 to build the Python 3 module.

Also, you’ll need the Leap driver and utils installed on your OS (follow instructions at https://www.leapmotion.com/setup/) and the leapd daemon running to recognize your controller.

Requires:

Triggers:

__init__(position_ranges=None, position_tolerance=0.0, frames_throttle_secs=None, *args, **kwargs)[source]
Parameters

position_ranges – It specifies how wide the hand space (x, y and z axes) should be in millimiters.

Default:

[
    [-300.0, 300.0],  # x axis
    [25.0, 600.0],    # y axis
    [-300.0, 300.0],  # z axis
]
Parameters
  • position_tolerance (float) – % of change between a frame and the next to really consider the next frame as a new one (default: 0)

  • frames_throttle_secs (float) – If set, the frame events will be throttled and pushed to the main queue at the specified rate. Good to set if you want to connect Leap Motion events to actions that have a lower throughput (the Leap Motion can send a lot of frames per second). Default: None (no throttling)

property daemon

A boolean value indicating whether this thread is a daemon thread.

This must be set before start() is called, otherwise RuntimeError is raised. Its initial value is inherited from the creating thread; the main thread is not a daemon thread and therefore all threads created in the main thread default to daemon = False.

The entire Python program exits when only daemon threads are left.

property ident

Thread identifier of this thread or None if it has not been started.

This is a nonzero integer. See the get_ident() function. Thread identifiers may be recycled when a thread exits and another thread is created. The identifier is available even after the thread has exited.

is_alive()

Return whether the thread is alive.

This method returns True just before the run() method starts until just after the run() method terminates. See also the module function enumerate().

join(timeout=None)

Wait until the thread terminates.

This blocks the calling thread until the thread whose join() method is called terminates – either normally or through an unhandled exception or until the optional timeout occurs.

When the timeout argument is present and not None, it should be a floating point number specifying a timeout for the operation in seconds (or fractions thereof). As join() always returns None, you must call is_alive() after join() to decide whether a timeout happened – if the thread is still alive, the join() call timed out.

When the timeout argument is not present or None, the operation will block until the thread terminates.

A thread can be join()ed many times.

join() raises a RuntimeError if an attempt is made to join the current thread as that would cause a deadlock. It is also an error to join() a thread before it has been started and attempts to do so raises the same exception.

property name

A string used for identification purposes only.

It has no semantics. Multiple threads may be given the same name. The initial name is set by the constructor.

property native_id

Native integral thread ID of this thread, or None if it has not been started.

This is a non-negative integer. See the get_native_id() function. This represents the Thread ID as reported by the kernel.

on_message(msg)

Callback when a message is received on the backend. It parses and posts the message on the main bus. It should be called by the derived classes whenever a new message should be processed.

Parameters

msg – Received message. It can be either a key-value dictionary, a platypush.message.Message object, or a string/byte UTF-8 encoded string

on_stop()

Callback invoked when the process stops

register_service(port: Optional[int] = None, name: Optional[str] = None, srv_type: Optional[str] = None, srv_name: Optional[str] = None, udp: bool = False, properties: Optional[Dict] = None)

Initialize the Zeroconf service configuration for this backend.

Parameters
  • port – Service listen port (default: the backend port attribute if available, or None).

  • name – Service short name (default: backend name).

  • srv_type – Service type (default: _platypush-{name}._{proto}.local.).

  • srv_name – Full service name (default: {hostname or device_id}.{type}).

  • udp – Set to True if this is a UDP service.

  • properties

    Extra properties to be passed on the service. Default:

    {
        "name": "Platypush",
        "vendor": "Platypush",
        "version": "{platypush_version}"
    }
    

run()[source]

Starts the backend thread. To be implemented in the derived classes if the loop method isn’t defined.

send_event(event, **kwargs)

Send an event message on the backend.

Parameters

event – Event to send. It can be a dict, a string/bytes UTF-8 JSON, or a platypush.message.event.Event object.

send_message(msg, queue_name=None, **kwargs)

Sends a platypush.message.Message to a node. To be implemented in the derived classes. By default, if the Redis backend is configured then it will try to deliver the message to other consumers through the configured Redis main queue.

Parameters
  • msg – The message to send

  • queue_name – Send the message on a specific queue (default: the queue_name configured on the Redis backend)

send_request(request, on_response=None, response_timeout=5, **kwargs)

Send a request message on the backend.

Parameters
  • request – The request, either a dict, a string/bytes UTF-8 JSON, or a platypush.message.request.Request object.

  • on_response (function) – Optional callback that will be called when a response is received. If set, this method will synchronously wait for a response before exiting.

  • response_timeout (float) – If on_response is set, the backend will raise an exception if the response isn’t received within this number of seconds (default: None)

send_response(response, request, **kwargs)

Send a response message on the backend.

Parameters
  • response – The response, either a dict, a string/bytes UTF-8 JSON, or a platypush.message.response.Response object.

  • request – Associated request, used to set the response parameters that will link them

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()

Stops the backend thread by sending a STOP event on its bus

unregister_service()

Unregister the Zeroconf service configuration if available.