Xcode Template for Pythonista

omz

@mrcoxall I'm aware of this problem, as it's also been affecting the main Pythonista app for a while. The reason for the error seems to be a server-side change in the way code signatures are verified. In short, iTunes Connect seems to use the file utility to check for executables in the bundle, and it then treats every Python file as an executable that should be signed (which isn't actually possible, as far as I'm aware). Of course, this is pretty much an edge case, as most iOS apps don't contain any scripts.

In recent betas (when the problem started appearing), I've used a somewhat dirty hack to work around this: The file utility basically uses some heuristics to determine the type of file (text/executable...), and it's possible to trick it into recognizing Python files as something else. There are probably multiple ways to do this – the one I'm using is to prepend files with a line that contains #\input texinfo, which makes file think that it's a TeX document.

I'm using a script similar to this for automating the process:

# Change these:
pylib_path1 = '<something like ".../PythonistaKit.framework/pylib">'
pylib_path2 = '<something like ".../PythonistaKit.framework/pylib_ext">'

import shutil
import os
import subprocess

def check_is_executable(file_path):
	file_output = subprocess.check_output(['file', file_path])
	if 'executable' in file_output:
		return True, file_output
	return False, file_output

def fix_executable(file_path):
	with open(file_path, 'r') as f:
		source = f.read()
	with open(file_path, 'w') as f:
		f.write('#\input texinfo\n' + source)
	is_executable, out = check_is_executable(file_path)
	return not is_executable

def fix_pylib(pylib_path, dry_run=False):
	for path, dirs, files in os.walk(pylib_path):
		for filename in files:
			full_path = full_path = os.path.join(path, filename)
			is_executable, file_output = check_is_executable(full_path)
			if is_executable:
				extension = os.path.splitext(full_path)[1].lower()
				if extension == '.py' or extension == '.pym' or filename == 'command_template':
					if dry_run:
						print '### Executable found: %s' % (filename,)
					else:
						print 'Fixing %s...' % (filename,)
						fixed = fix_executable(full_path)
						if not fixed:
							print '### FIXING %s FAILED' % (full_path,)
						else:
							print 'Fixed'
				else:
					print '### Executable found, but does not seem to be Python code: %s' % (full_path,)

if __name__ == '__main__':
	fix_pylib(pylib_path1)
	fix_pylib(pylib_path2)

mrcoxall

@omz Thanks so much for getting back to me.
I will give it a try and see what happens.

By any chance do you have an update to the GitHub repo with the changes already made to the pylib and pylib_ext, so that I do not have to run the scrip and change anything?

Thanks again, Patrick

polymerchm

Trying to run my app via xcode and the current template. How do you force it to run the Python 3 interpretor?

mrcoxall

@omz I have used your script and changed all the files in pylib and pylib_ext. I even placed the header at the top of the files in "scripts". It still compiles OK to simulator and devices but I am still getting a code signing error.

error screenshot

Any ideas?
Here is my fork with the fix: https://github.com/Mr-Coxall/PythonistaAppTemplate

omz

@mrcoxall It looks like you're submitting the app directly from the Xcode organizer? Try exporting the archive first ("for App Store deployment"), and then submit it using the Application Loader tool (right-click Xcode in Dock -> Open Developer Tool...). Not sure if this will actually fix the error, but I've seen similar problems in the past that only happened with Xcode, and not with Application Loader.

polymerchm

@omz Based on my experiments, am I correct in assuming that the template only has the 2.7 interpretor? Any hope the the 3.5/3.6 template will be forthcoming? I am learning swift just in case.

mrcoxall

@omz I tried as you suggest and used the Application Loader. Same problem happening. Still getting code signing errors. Have tried using "Auto code signing" and even old school downloading the certificate myself and still getting the same messages.
Have you been able to get anything uploaded to the App Store?
Do you have a template that I could try?

Thanks

mrcoxall

Wondering if anyone has been able to submit an app successfully since Jan 1, 2017.
I still am getting signing errors and have no workaround that will work.
I have app waiting to get approved and need a solution.

Thanks

JonB

Have you tried the recommendations here?
http://stackoverflow.com/questions/39889093/itunes-software-service-authentication-error-domain-error-434

kyelewis

I know this is an older thread, but I just wanted to confirm that with the texinfo fix, I have successfully submitted and had an app approved in the last few days.

So the fix is required to get past the automatic filter, but submission is OK with the workaround.

marcus67

@omz Getting back to the question of @polymerchm : Is it possible to run python3 in Xcode? Using a she-bang line like "#! python3" does not work. sys.version still returns "2.7.5 (default, Feb 15 2016, 15:15:36)". Thanks!

omz

@marcus67 It's currently not possible, I'm afraid.

mrcoxall

@omz Thanks for getting back to me.

I was wondering if there is any explanation on why it is no longer possible?
I used Pythonista last year with my grade 11 programming course and got over a dozen apps published on the App Store. I have just started using it again with this years group and told them we will be doing the same thing. If there is anything I can do to help the process along, please let me know. We will not be starting to write the final apps until December.

Thanks

JonB

This post is deleted!

JonB

@mrcoxall Did youthe texinfo trick? Sounds like @kyelewis got something submitted in january or february.

TheRealBret

@JonB The texinfo trick continues to work. Had an app accepted just last week.

ccc

Would it be possible to create a repo or a page on Pythonista-Tools that could be a FAQ for using the template? It seems like there are several prereqs and then several steps to complete the process and it would be great to have a landing page for sharing all that tribal knowledge.

TheRealBret

I spoke too soon. I had to upgrade Xcode because of iOS11 compatibility, and now I'm back to getting the code signing errors for all the .py files, even if they have the texinfo header. Building apps for local distribution works fine, I just can't sign the code as part of the validation process for the App Store.

TheRealBret

Looks like the texinfo hack needs to be modified. The code signing process uses file(1) to check the type of file in the package, and file(1) identifies executable code by checking against different file types and scoring each file type. Apple modified the matching "magic" for python to look for python keywords like "def", "import", "try", "except", etc and each use gives a higher score to python. So for the tex info hack to work, it needs to occur more frequently than the python keywords. Some files just need a single texinfo line; other files need 400+ copies of the texinfo line (some of the python checks only examine the first 4096 characters of the file). Its easy to modify the script above to accomplish this, but hardly elegant.

Hopefully somebody will find this useful and find a simple fix.... like perhaps there's another file type that short-circuits the checking magic? Also, the Apple developer documentation say that script files could go into a specially named subfolder, which would be much simpler, but I've haven't gotten this to work.

JonB

out of curiosity, is file used locally, or on the server?
Couldn't you use th older file version for identifying text files?