Correct way to call Pythonista script from within a Shortcuts workflow?

[cvp]

@mikeno ok, I thought that calling the script from the shortcut did launch Pythonista even if iPad not awake. If you have Pyto, you could test because it runs really in background like a music player

[mikeno]

I don’t know PyTo but I will try, thx in any case

[cvp]

@mikeno not Py To but Pyto, I think there is a free test version

[mikeno]

I just downloaded it but my trial period already expired because I probably already tried it some times ago and since I don’t know if it works, I don’t want to buy it. If you’ve it, could you try if it runs when iPad is asleep?

[cvp]

@mikeno I'll do it and let it know

[cvp]

@mikeno I have tried a script which prints the time each second and closed my iPad cover during 200 seconds and when I have reopened it, the script was still running

[mikeno]

Thx, the question is now if Pyto can read the barometer sensor value, below a short code which runs fine under Pythonista:

from objc_util import ObjCInstance, ObjCClass, ObjCBlock, c_void_p

pressure = None

def get_pressure():
  
  def handler(_cmd, _data, _error):
    global pressure
    pressure = ObjCInstance(_data).pressure()

  handler_block = ObjCBlock(handler, restype=None, argtypes=[c_void_p, c_void_p, c_void_p])

  CMAltimeter = ObjCClass('CMAltimeter')
  NSOperationQueue = ObjCClass('NSOperationQueue')
  if not CMAltimeter.isRelativeAltitudeAvailable():
    print('This device has no barometer.')
    return
  altimeter = CMAltimeter.new()
  main_q = NSOperationQueue.mainQueue()
  altimeter.startRelativeAltitudeUpdatesToQueue_withHandler_(main_q, handler_block)
  try:
    while pressure is None:
      pass
  finally:
    altimeter.stopRelativeAltitudeUpdates()
    #print('Updates stopped.')
    return pressure.floatValue()*10

pressure = get_pressure()
print(pressure)

[cvp]

@mikeno I know this code but I'm new in Pyto and surely not (yet?) a specialist in ObjectiveC of Pyto.
I don't not yet know how to define an ObjcBlock in Pyto but I'll try.
But, obviously, I'll need some time

[cvp]

@mikeno Sorry, no idea how to define an ObjcBlock in rubicon (ObjectiveC in Pyto).
Hoping that @JonB will read this and be able to help, as usual.

# coding: utf-8
from rubicon.objc import *
from  ctypes import *

def handler(_cmd, _data, _error):
    print(ObjCInstance(_data))

handler_block = ObjCBlock(handler, None, [c_void_p, c_void_p, c_void_p])

def main():
    CMAltimeter = ObjCClass('CMAltimeter')
    NSOperationQueue = ObjCClass('NSOperationQueue')
    if not CMAltimeter.isRelativeAltitudeAvailable():
        print('This device has no barometer.')
        return
    altimeter = CMAltimeter.new()
    main_q = NSOperationQueue.mainQueue
    altimeter.startRelativeAltitudeUpdatesToQueue_withHandler_(main_q, handler_block)
    print('Started altitude updates.')
    try:
        while True:
            pass
    finally:
        altimeter.stopRelativeAltitudeUpdates()
        print('Updates stopped.')

if __name__ == '__main__':
    main()

Gives

Traceback (most recent call last):
  File "iCloud/barometer.py", line 8, in <module>
    handler_block = ObjCBlock(handler, None, [c_void_p, c_void_p, c_void_p])
  File "Pyto.app/Lib/rubicon/objc/api.py", line 1834, in __init__
    self.struct = cast(self.pointer, POINTER(ObjCBlockStruct))
  File "Pyto.app/site-packages/python3.10/ctypes/__init__.py", line 510, in cast
    return _cast(obj, obj, typ)
ctypes.ArgumentError: argument 1: <class 'TypeError'>: wrong type

[mikeno]

Thx for trying, I’ll wait!

[JonB]

@cvp I believe in Rubicon, the preferred usage is via type annotations and decorators. Also ObjCBlock wraps ObjC blocks so they can be called in python, while Block wraps python so it is calls me in objc-- so you want plain old Block.

I think the way you'd do it in Rubicon is:

(Edited)

@Block
def handler(altitudeData: ObjCInstance, err:NSError) -> None:
    print(altitudeData)

Or, I think you can skip the annotation on ObjCInstances:

@Block
def handler(altitudeData, err:NSError) -> None:
    print(altitudeData)

[cvp]

@JonB problems
1)

@Block
def handler(altitudeData , err:NSError) -> None:
    print(altitudeData)

handler_block = ObjCBlock(handler, None, [c_void_p, c_void_p])

Gives

Traceback (most recent call last):
  File "iCloud/barometer.py", line 6, in <module>
    def handler(altitudeData, err:NSError) -> None:
NameError: name 'NSError' is not defined. Did you mean 'OSError'?

@Block
def handler(altitudeData, err) -> None:
    print(altitudeData)

handler_block = ObjCBlock(handler, None, [c_void_p, c_void_p])

Gives

Traceback (most recent call last):
  File "iCloud/barometer.py", line 6, in <module>
    def handler(altitudeData, err) -> None:
  File "Pyto.app/Lib/rubicon/objc/api.py", line 1939, in __init__
    raise ValueError(
ValueError: Function has no argument type annotation for parameter 'altitudeData' - please add one, or
 pass return and argument types directly into Block

@Block
def handler(altitudeData:ObjCInstance, err:ObjCInstance) -> None:
   print(altitudeData)

handler_block = ObjCBlock(handler, None, [c_void_p, c_void_p])

Gives

Traceback (most recent call last):
  File "iCloud/barometer.py", line 9, in <module>
    handler_block = ObjCBlock(handler, None, [c_void_p, c_void_p])
  File "Pyto.app/Lib/rubicon/objc/api.py", line 1846, in __init__
    self.struct.contents.invoke.argtypes = (objc_id, ) + tuple(ctype_for_type(arg_type) for arg_type i
n argtypes)
  File "Pyto.app/Lib/rubicon/objc/api.py", line 1846, in <genexpr>
    self.struct.contents.invoke.argtypes = (objc_id, ) + tuple(ctype_for_type(arg_type) for arg_type i
n argtypes)
  File "Pyto.app/Lib/rubicon/objc/types.py", line 103, in ctype_for_type
    return _ctype_for_type_map.get(tp, tp)
TypeError: unhashable type: 'list'

@Block
def handler(altitudeData:ObjCInstance, err:ObjCInstance) :#-> None:
    print(altitudeData)

handler_block = ObjCBlock(handler, None)#, [c_void_p, c_void_p])

Gives

Traceback (most recent call last):
  File "iCloud/barometer.py", line 6, in <module>
    def handler(altitudeData:ObjCInstance, err:ObjCInstance) :#-> None:
  File "Pyto.app/Lib/rubicon/objc/api.py", line 1930, in __init__
    raise ValueError(
ValueError: Function has no return type annotation - please add one, or pass return and argument types
 directly into Block
Traceback (most recent call last):
  File "iCloud/barometer.py", line 6, in <module>
    def handler(altitudeData:ObjCInstance, err:ObjCInstance) :#-> None:
  File "Pyto.app/Lib/rubicon/objc/api.py", line 1930, in __init__
    raise ValueError(
ValueError: Function has no return type annotation - please add one, or pass return and argument types
 directly into Block

@Block
def handler(altitudeData:ObjCInstance, err:ObjCInstance) -> None:
    print(altitudeData)
    
handler_block = ObjCBlock(handler, None, (c_void_p, c_void_p))

Gives

Traceback (most recent call last):
  File "iCloud/barometer.py", line 10, in <module>
    handler_block = ObjCBlock(handler, None, (c_void_p, c_void_p))
  File "Pyto.app/Lib/rubicon/objc/api.py", line 1846, in __init__
    self.struct.contents.invoke.argtypes = (objc_id, ) + tuple(ctype_for_type(arg_type) for arg_type i
n argtypes)
TypeError: item 2 in _argtypes_ has no from_param method

[bosco]

@mikeno This code works for me with the latest version of pyto.

# coding: utf-8
from rubicon.objc import Block, ObjCClass, ObjCInstance, py_from_ns
from rubicon.objc.runtime import objc_id

pressure = None

def handler(_data) -> None:
    nspressure = ObjCInstance(_data).pressure
    global pressure
    pressure = py_from_ns(nspressure)

handler_block = Block(handler, None, (objc_id))

def get_pressure():
    CMAltimeter = ObjCClass('CMAltimeter')
    NSOperationQueue = ObjCClass('NSOperationQueue')
    if not CMAltimeter.isRelativeAltitudeAvailable():
        print('This device has no barometer.')
        return
    altimeter = CMAltimeter.new()
    main_q = NSOperationQueue.mainQueue
    altimeter.startRelativeAltitudeUpdatesToQueue_withHandler_(main_q, handler_block)
    print('Started altitude updates.')
    try:
        while pressure is None:
            pass
    finally:
        altimeter.stopRelativeAltitudeUpdates()
        print('Updates stopped.')
        return pressure

if __name__ == '__main__':
    result = get_pressure()
    print(result)
    del pressure

[cvp]

@bosco Thanks for him, and for me, so I don't have to test anymore.
Do you know why the handler does not have a 2nd parameter (error) like described in Apple doc?

[JonB]

@cvp, I think this one was correct:

@Block
def handler(altitudeData:ObjCInstance, err:ObjCInstance) -> None:
   print(altitudeData)

But then pass handler directly to ObjC -- don't call ObjCBlock on it. ObjCBlock makes an Objc block callable by python, which isn't needed here.

Or, to make no other changes:

@Block
def handler_block(altitudeData:ObjCInstance, err:ObjCInstance) -> None:
   print(altitudeData)

[cvp]

@mikeno With the barometer module of @bosco, where print lines are commented, this script works and continues to log the pressure even if I close the iPad cover. Not tested during a day.

import background as bg
import barometer

with bg.BackgroundTask() as b:
  while True:
    result = barometer.get_pressure()
    l= f"{b.execution_time()}:{result}\n"
    with open("/private/var/mobile/Library/Mobile Documents/iCloud~is~workflow~my~workflows/Documents/bg.txt", mode='at') as fil:
      fil.write(l)
    #print(b.execution_time(), result)
    b.wait(5)

[mikeno]

Hi everybody, thx for helping, I’ll buy Pyto and try.

[cvp]

@JonB said

But then pass handler directly to ObjC

how do I do that?

In the bosco solution, there is no @Block line

Édit: ok, understood, use the handler_block directly in

    altimeter.startRelativeAltitudeUpdatesToQueue_withHandler_(main_q, handler)

Thanks for your explanations

Edit2: but I need

@Block
def handler(altitudeData:ObjCInstance, err:ObjCInstance) -> None:
   print(ObjCInstance(altitudeData).pressure)

[bosco]

I dropped the 2nd parameter (error) because it caused an exception: "item 2 in argtypes has no from_param method", so I tried running without the error parameter.

After reading the last comment by @JonB I now understand the proper use of @Block witch can be called directly.

This works for me.

# coding: utf-8
from rubicon.objc import Block, ObjCClass, ObjCInstance, py_from_ns
from rubicon.objc.runtime import objc_id

pressure = None

@Block
def handler(altitudeData:ObjCInstance, err:ObjCInstance) -> None:
    nspressure = ObjCInstance(altitudeData).pressure
    global pressure
    pressure = py_from_ns(nspressure)

"""
def bhandler(_data) -> None:
    nspressure = ObjCInstance(_data).pressure
    global pressure
    pressure = py_from_ns(nspressure)

handler_block = Block(bhandler, None, (objc_id))
"""

def get_pressure():
    CMAltimeter = ObjCClass('CMAltimeter')
    NSOperationQueue = ObjCClass('NSOperationQueue')
    if not CMAltimeter.isRelativeAltitudeAvailable():
        print('This device has no barometer.')
        return
    altimeter = CMAltimeter.new()
    main_q = NSOperationQueue.mainQueue
    #altimeter.startRelativeAltitudeUpdatesToQueue_withHandler_(main_q, handler_block)
    altimeter.startRelativeAltitudeUpdatesToQueue_withHandler_(main_q, handler)
    print('Started altitude updates.')
    try:
        while pressure is None:
            pass
    finally:
        altimeter.stopRelativeAltitudeUpdates()
        print('Updates stopped.')
        return pressure

if __name__ == '__main__':
    result = get_pressure()
    print(result)
    del pressure

[cvp]

@bosco said

After reading the last comment by @JonB I now understand the proper use of @Block witch can be called directly.

Yes, this is what I had also found and explained in my last post