Pythonista 1.6 Beta

wradcliffe

I was able to use the Bluetooth LE module to talk to a LightBlue Bean and enumerate all of its services and characteristics.

I also tried reading all the values for each characteristic and ran into one problem. The values returned may or may not be text strings and if you simply assume they are and print them to the console you can get the module to throw an exception

TypeError: must be string without null bytes, not str

Trace back says it happened at line 73 in cb.py

After that you can recover but you can also crash completely or leave the module in a bad state and unable to talk to the peripheral.

Here is my code:

import cb
import sound
import time
import struct

class LightBlueBean (object):
	def __init__(self):
		self.peripheral = None

	def did_discover_peripheral(self, p):
		print 'Discovered:', p.name
		if p.name and 'Bean' in p.name and not self.peripheral:
			self.peripheral = p
			print 'Connecting to Bean...'
			cb.connect_peripheral(p)

	def did_connect_peripheral(self, p):
		print 'Connected:', p.name
		print 'Discovering services...'
		p.discover_services()

	def did_fail_to_connect_peripheral(self, p, error):
		print 'Failed to connect: %s' % (error,)

	def did_disconnect_peripheral(self, p, error):
		print 'Disconnected, error: %s' % (error,)
		self.peripheral = None

	def did_discover_services(self, p, error):
		print 'Did discover services...'
		for s in p.services:
			print 'Service:', s.uuid
			if True: # s.uuid == '180D'
				print 'Discovering characteristics...'
				p.discover_characteristics(s)

	def did_discover_characteristics(self, s, error):
		print 'Did discover characteristics...'
		for c in s.characteristics:
			print 'Characteristic:', c.uuid, ' Value:', c.value
			#if c.uuid == '2A37':
			#	self.peripheral.set_notify_value(c, True)
			self.peripheral.read_characteristic_value(c)

	def did_update_value(self, c, error):
		#somevalue = struct.unpack('<B', c.value[1])[0]
		#self.values.append(somevalue)
		#print 'Value: %i' % somevalue
		print 'Update to a value...'
		print 'Characteristic:', c.uuid, ' Value:', c.value

mngr = LightBlueBean()
cb.set_central_delegate(mngr)
print 'Scanning for peripherals...'
cb.scan_for_peripherals()

try:
	while True: pass
except KeyboardInterrupt:
	print 'keyboard interrupt - resetting'
	cb.reset()

Here is the console output:

Scanning for peripherals...
Discovered: Bean
Connecting to Bean...
Connected: Bean
Discovering services...
Disconnected, error: (10, u'The connection has failed unexpectedly.')
keyboard interrupt - resetting
Scanning for peripherals...
Discovered: Bean
Connecting to Bean...
Connected: Bean
Discovering services...
Did discover services...
Service: F000FFC0-0451-4000-B000-000000000000
Discovering characteristics...
Service: 180A
Discovering characteristics...
Service: A495FF10-C5B1-4B44-B512-1370F02D74DE
Discovering characteristics...
Service: A495FF20-C5B1-4B44-B512-1370F02D74DE
Discovering characteristics...
Service: 180F
Discovering characteristics...
Did discover characteristics...
Characteristic: F000FFC1-0451-4000-B000-000000000000  Value: None
Characteristic: F000FFC2-0451-4000-B000-000000000000  Value: None
Did discover characteristics...
Characteristic: 2A23  Value: None
Characteristic: 2A24  Value: None
Characteristic: 2A25  Value: None
Characteristic: 2A26  Value: None
Characteristic: 2A27  Value: None
Characteristic: 2A28  Value: None
Characteristic: 2A29  Value: None
Characteristic: 2A2A  Value: None
Characteristic: 2A50  Value: None
Did discover characteristics...
Characteristic: A495FF11-C5B1-4B44-B512-1370F02D74DE  Value: None
Did discover characteristics...
Characteristic: A495FF21-C5B1-4B44-B512-1370F02D74DE  Value: None
Characteristic: A495FF22-C5B1-4B44-B512-1370F02D74DE  Value: None
Characteristic: A495FF23-C5B1-4B44-B512-1370F02D74DE  Value: None
Characteristic: A495FF24-C5B1-4B44-B512-1370F02D74DE  Value: None
Characteristic: A495FF25-C5B1-4B44-B512-1370F02D74DE  Value: None
Did discover characteristics...
Characteristic: 2A19  Value: None
Update to a value...
Characteristic: F000FFC1-0451-4000-B000-000000000000  Value: None
Update to a value...
Characteristic: F000FFC2-0451-4000-B000-000000000000  Value: None
Update to a value...
Characteristic: 2A23  Value: Update to a value...
Characteristic: 2A24  Value: Bean
Update to a value...
Characteristic: 2A25  Value: Serial Number
Update to a value...
Characteristic: 2A26  Value: 201409080001 Img-B
Update to a value...
Characteristic: 2A27  Value: E
Update to a value...
Characteristic: 2A28  Value: Software Revision
Update to a value...
Characteristic: 2A29  Value: Punch Through Design
Update to a value...
Characteristic: 2A2A  Value: Update to a value...
Characteristic: 2A50  Value: Update to a value...
Characteristic: A495FF11-C5B1-4B44-B512-1370F02D74DE  Value: Update to a value...
Characteristic: A495FF21-C5B1-4B44-B512-1370F02D74DE  Value: 
Update to a value...
Characteristic: A495FF22-C5B1-4B44-B512-1370F02D74DE  Value: 
Update to a value...
Characteristic: A495FF23-C5B1-4B44-B512-1370F02D74DE  Value: 
Update to a value...
Characteristic: A495FF24-C5B1-4B44-B512-1370F02D74DE  Value: 
Update to a value...
Characteristic: A495FF25-C5B1-4B44-B512-1370F02D74DE  Value: 
Update to a value...
Characteristic: 2A19  Value: 1
keyboard interrupt - resetting

dgelessus

Instead of a plain print(data), try using print(data.replace("\x00", "")), with data being the value received from the peripheral. This simply removes any null bytes from the string to stop print from complaining. For debugging purposes you might want to replace null bytes with something like "NULL" so you can find them in the printed text.

userista

Is it new in this version that the various console.alert "types" now return the button number (as an int)? It broke a couple of my scipts...

omz

@wradcliffe

Most strings you're dealing with will probably be binary data, so I'd recommend encoding them as hex before printing (print c.value.encode('hex')). Nevertheless, there are definitely some stability issues when you encounter exceptions in any of the callbacks. I might change this to disconnect when an exception is thrown in a callback, which might make it more likely to recover successfully.

@hyshai

Is it new in this version that the various console.alert "types" now return the button number (as an int)? It broke a couple of my scipts...

The standard alert() function always did this, but I assume you're referring to other alert types? There are definitely some bugs with those right now, looking into it.

@the_buch

for reminders.get_reminders(completed=TRUE) is there currently, or could there be in a future version, a way to filter completed reminders with completion date.

Right now, it's not possible, but I will at the very least add a completion_date attribute to the Reminder class, so you could filter them manually.

@Moe

I assume the appex module you teased on Twitter is not integrated/activated in this Beta?

No, this won't be in 1.6.

@dgelessus

The Pythonista.app bundle is now fully moved out of the "Data" folder and no longer easily accessible (sad face)

That's an iOS 8 thing, nothing I can do about it, though it is still accessible if you have the correct path. Right now, you could do this with scene.get_image_path (which will return a path that is within the app bundle, you'd have to walk up the hierarchy a bit to get the root directory of the app).

omz

@the_buch

Also would like to see this module in Editorial eventually. Better than using url schemes in all these reminder workflows.

Yes, the reminders module will definitely be in the next update of Editorial as well, same goes for twitter and probably dialogs. I don't plan to integrate cb in Editorial though.

wradcliffe

I have been working with the dialogs form_dialog and this test code:

import dialogs
import datetime

dt = datetime.datetime.now()
fields = [
  {'key' : 'the_key0', 'type' : 'switch', 'value' : 'the_value'},
  {'key' : 'the_key1', 'type' : 'text', 'value' : 'the_value'},
  {'key' : 'the_key2', 'type' : 'url', 'value' : 'the_value'},
  {'key' : 'the_key3', 'type' : 'email', 'value' : 'the_value'},
  {'key' : 'the_key4', 'type' : 'password', 'value' : 'the_value'},
  {'key' : 'the_key5', 'type' : 'number', 'value' : '100' },
  {'key' : 'the_key6', 'type' : 'check', 'value' : 'the_value'},
  {'key' : 'the_key7', 'type' : 'datetime', 'value' : dt},
  {'key' : 'the_key8', 'type' : 'date', 'value' : dt},
  {'key' : 'the_key9', 'type' : 'time', 'value' : dt}
]
result=dialogs.form_dialog(title='look at all this stuff', fields=fields)
print 'text:', result

When I look at this, I can't help thinking that all the field data should be aligned right and that there should be labels on each one. Should there be a 'label' key added? How is the user suppose to know what each field represents?

I suppose you could use sections to implement labels, but that seems wrong. Section as a way of breaking up and labeling combinations of like fields is good.

sections = [
  ('switch section', [{'key' : 'the_key0', 'type' : 'switch', 'value' : 'the_value'}]),
  ('text section', [{'key' : 'the_key1', 'type' : 'text', 'value' : 'the_value'}])
]
result=dialogs.form_dialog(title='look at all this stuff', sections=sections)
print 'text:', result

Also - datetime requires/returns a datetime and date and time do as well. Should date and time require and return date and time objects?

Also, Also - email, url, number don't seem to do anything different then text. Shouldn't they be enforcing formatting or something?

omz

How is the user suppose to know what each field represents?

There's a 'title' key you can use, the documentation is a little incomplete right now with regards to the supported keys.

Also - datetime requires/returns a datetime and date and time do as well. Should date and time require and return date and time objects?

Maybe, it was a bit easier to implement this way, and you can easily convert it to a date or time object by calling datetime.date() or datetime.time().

Also, Also - email, url, number don't seem to do anything different then text. Shouldn't they be enforcing formatting or something?

The keyboard for URL and email fields is different (e.g. the email keyboard has an additional '@' key), and they have autocorrection disabled by default.

techteej

text = dialogs.text_dialog(title='Name Your Reminder', autocapitalization=ui.AUTOCAPITALIZE_SENTENCES, spellchecking=None)
r = reminders.Reminder()
r.title = text
r.save()

Gives me a excepted string error.

omz

@techteej Did you use the Done button in the text dialog? If you cancel the dialog (via 'x'), it'll return None.

techteej

It shows up while the dialog is up

omz

@techteej Is that really your entire code?

wradcliffe

There's a 'title' key you can use ...

The title key works perfectly. I noticed that the text color defaults to black except for the checkbox case where it is blue (or same as check color).

Looking forward to more keys assuming now that you are going to have color, font, etc. to really allow full control.

What about field validation? Popping up a special keyboard is nice, but a delegate function called on each keystroke would nail it. I used to work on named entity extraction in text and you can do a lot with simple regex matching, but you need to run code to do credit card numbers (for the checksum). I think mapping field types to entities would be super cool.

techteej

@omz Here is my entire code.

# coding: utf-8
import dialogs
import reminders
import ui

class Data (ui.ListDataSource):
	def __init__(self, items=None):
		ui.ListDataSource.__init__(self, items)

	def tableview_cell_for_row(self, tableview, section, row):
		cell = ui.TableViewCell()
		cell.text_label.text = str(self.items[row])
		return cell

v = ui.load_view('reminders')

def button_action(sender):
	if segment.selected_index == 0:
		todo = reminders.get_reminders(completed=False)
		for r in todo:
			full = r.title
			reminders_table.data_source = Data(items=[full])
			reminders_table.reload()
	elif segment.selected_index == 1:
		done = reminders.get_reminders(completed=True)
		for r in done:
			full = r.title
			reminders_table.data_source = Data(items=[full])
			reminders_table.reload()

def but_action(sender):
	text = dialogs.text_dialog(title='Name Your Reminder', autocapitalization=ui.AUTOCAPITALIZE_SENTENCES, spellchecking=None)
	r = reminders.Reminder()
	r.title = text
	r.save()

segment = v['segmentedcontrol1']
segment.action = button_action
reminders_table = v['reminders']

create_button = ui.ButtonItem()
create_button.image = ui.Image.named('ionicons-ios7-plus-empty-32')
create_button.action = but_action

v.right_button_items = [create_button]
v.present('sheet')

omz

@techteej Similar to console alerts, dialogs don't work from the main UI thread (allowing this would essentially lead to a deadlock). Try decorating your but_action function with @ui.in_background.

techteej

Found a bug. In the UI Editor when delete enabled is off, you can still delete rows in a table.

TutorialDoctor

Will dialogs allow me to create tables with cells (rows and columns)?

This would be most useful, otherwise I don't see an advantage to dialogs over UI.

Pinch to zoom in the UI editor would be nice too, as well as saving UI control presets.

andymitchhank2

The beta doesn't seem to ask for permission to use Location Services when using the location module for the first time.

I thought it might be for all required permissions, but the Reminders seems to work fine.

Anyone have any ideas on this?

omz

Found a bug. In the UI Editor when delete enabled is off, you can still delete rows in a table.

I can't reproduce this. Note however that the "delete enabled" attribute only applies to the default ListDataSource that gets created as a convenience when loading a TableView from a pyui file. If you set a different data source after loading the view, it doesn't have an effect.

Will dialogs allow me to create tables with cells (rows and columns)?
This would be most useful, otherwise I don't see an advantage to dialogs over UI.

No. For the most part, dialogs doesn't really let you do things you couldn't do with the ui module, but things like form_dialog would require a lot more code when done with ui directly. There are also some things that you couldn't do otherwise, like dialogs.import_file() or dialogs.share().

The beta doesn't seem to ask for permission to use Location Services when using the location module for the first time.

Are you sure that you didn't give permission with the previous version? The beta would inherit those permissions (it's the same app after all).

andymitchhank2

I uninstalled the beta, installed the current App Store version and ran a simple get location script. It prompted for Location permissions and retrieved my location.

I then uninstalled the App Store version, installed the beta again and ran the script.

The script prints out the value of location.get_location(). It is currently printing out None in the beta with no prompt to allow access to Location Services.

zencuke

Bluetooth LE? Bless you! I'd love to beta test that. Sending email as soon as I track down your email address ;-)

-steve (aka zencuke)