gallery-dl doesn't work with lua subprocess

[phanirithvij]

OS: Windows 10

[gallery-dl][debug] Version 1.13.2
[gallery-dl][debug] Python 3.8.0 - Windows-10-10.0.18362-SP0
[gallery-dl][debug] requests 2.23.0 - urllib3 1.25.6

Gallery-dl.exe is in my PATH.

This call works when called from python

python py.py "https://imgur.com/a/7AtGJJg" 

# file py.py
import sys
import subprocess

result = subprocess.check_output(["gallery-dl", "-g", sys.argv[1]])
print(result.decode('utf8').strip())

Output

https://i.imgur.com/sUWPlCL.png
https://i.imgur.com/MsXOF90.png
https://i.imgur.com/aHFeZJe.png
https://i.imgur.com/HHyTd7i.png
https://i.imgur.com/8B95XmK.png
https://i.imgur.com/3kS88XJ.png
https://i.imgur.com/twleH7a.png
https://i.imgur.com/HlTMB9U.png
https://i.imgur.com/u6uGJsY.png
https://i.imgur.com/9ML4Csl.png
https://i.imgur.com/c8vj8Na.png
https://i.imgur.com/thrIFE5.png
https://i.imgur.com/vgjUCdt.png
https://i.imgur.com/AqWAj4u.png
https://i.imgur.com/04pmPk1.png
https://i.imgur.com/tzigNb7.png
https://i.imgur.com/zDfW42L.png

But when executing it in lua.

url = "https://imgur.com/a/7AtGJJg" 
file = assert(io.popen("gallery-dl -g " .. url, 'r'))
-- file = assert(io.popen("bash -c gallery-dl -g " .. url, 'r'))
output = file:read('*all')
file:close()
print(output)

The error is this

Traceback (most recent call last):
  File "c:\users\rithvij\appdata\local\programs\python\python38\lib\runpy.py", line 192, in _run_module_as_main
    return _run_code(code, main_globals, None,
  File "c:\users\rithvij\appdata\local\programs\python\python38\lib\runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "C:\Users\Rithvij\AppData\Local\Programs\Python\Python38\Scripts\gallery-dl.exe\__main__.py", line 7, in <module>
  File "c:\users\rithvij\appdata\local\programs\python\python38\lib\site-packages\gallery_dl\__init__.py", line 112, in main
    output.replace_std_streams()
  File "c:\users\rithvij\appdata\local\programs\python\python38\lib\site-packages\gallery_dl\output.py", line 153, in replace_std_streams
    stream.buffer,
AttributeError: 'NoneType' object has no attribute 'buffer'

[mikf]

sys.stdout, .stderr, or .stdin can be None when the underlying file descriptors are closed at process start, and I didn't anticipate that. Should be fixed with 4bc161c

[phanirithvij]

Please add a test for the subprocess if possible. I don't see how it can be done in python as it worked before this fix. Guess python subprocess module calls the program attached to a shell. But Lua doesn't.

This can be marked as resolved. I was able to call gallery-dl from Lua's subprocess. Thank you.

[mikf]

Guess python subprocess module calls the program attached to a shell. But Lua doesn't.

Running your lua script works just fine on my machine, even with a gallery-dl version before 4bc161c, so there is probably something else going on, but at least it now also works for you.

$ git checkout v1.13.0
$ lua -v
Lua 5.3.5  Copyright (C) 1994-2018 Lua.org, PUC-Rio
$ lua /tmp/script.lua 
https://i.imgur.com/sUWPlCL.png
https://i.imgur.com/MsXOF90.png
https://i.imgur.com/aHFeZJe.png
...