Make setup.py OS-agnostic and replace fcntl with an OS-agnostic alternative

[Andrew-S-Rosen]

What should we add?

Setting aside some potential UI challenges, if you want to make Covalent Electron objects compatible with Windows (e.g. to use as regular functions), I don't think it's all that difficult.

---

The first change is to modify open("README.md").read() to be open("README.md", encoding="utf8").read() below so the Windows user can pip install covalent.

covalent/setup.py

Line 209 in 90d1560

"long_description": open("README.md").read(),

Edit: This was merged in #1685.

---

The second change is to use an OS-agnostic locking mechanism in place of fcntl below so the config file can be properly written. Portalocker is one such option, which is basically a drop-in replacement of fcntl.lockf(f, fcntl.LOCK_EX) with portalocker.lock(f, portalocker.LOCK_EX).

covalent/covalent/_shared_files/config.py

Lines 112 to 148 in 90d1560

	with open(self.config_file, "r+") as f:
	fcntl.lockf(f, fcntl.LOCK_EX)
	file_config = toml.load(f)
	update_nested_dict(self.config_data, file_config)
	if new_entries:
	update_nested_dict(self.config_data, new_entries, override_existing)
	# Writing it back to the file
	self.write_config()
	def read_config(self) -> None:
	"""
	Read the configuration from file.
	Args:
	None
	Returns:
	None
	"""
	self.config_data = toml.load(self.config_file)
	def write_config(self) -> None:
	"""
	Write the configuration to file.
	Args:
	None
	Returns:
	None
	"""
	with open(self.config_file, "w") as f:
	fcntl.lockf(f, fcntl.LOCK_EX)
	toml.dump(self.config_data, f)

---

Once those two changes are made, you can import/use Electron objects as normal functions on Windows.

Describe alternatives you've considered.

No response

[sgbaird]

covalent start on Windows 11 for me results in:

Traceback (most recent call last):
  File "<frozen runpy>", line 198, in _run_module_as_main
  File "<frozen runpy>", line 88, in _run_code
  File "C:\Users\sterg\miniconda3\envs\self-driving-lab-demo\Scripts\covalent.exe\__main__.py", line 4, in <module>
  File "C:\Users\sterg\miniconda3\envs\self-driving-lab-demo\Lib\site-packages\covalent_dispatcher\__init__.py", line 17, in <module>    
    from .entry_point import cancel_running_dispatch, run_dispatcher
  File "C:\Users\sterg\miniconda3\envs\self-driving-lab-demo\Lib\site-packages\covalent_dispatcher\entry_point.py", line 24, in <module> 
    from covalent._shared_files import logger
  File "C:\Users\sterg\miniconda3\envs\self-driving-lab-demo\Lib\site-packages\covalent\__init__.py", line 22, in <module>
    from . import executor, leptons  # nopycln: import
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\sterg\miniconda3\envs\self-driving-lab-demo\Lib\site-packages\covalent\executor\__init__.py", line 32, in <module>      
    from .._shared_files import logger
  File "C:\Users\sterg\miniconda3\envs\self-driving-lab-demo\Lib\site-packages\covalent\_shared_files\logger.py", line 24, in <module>   
    from .config import get_config
  File "C:\Users\sterg\miniconda3\envs\self-driving-lab-demo\Lib\site-packages\covalent\_shared_files\config.py", line 199, in <module>  
    _config_manager = ConfigManager()
                      ^^^^^^^^^^^^^^^
  File "C:\Users\sterg\miniconda3\envs\self-driving-lab-demo\Lib\site-packages\covalent\_shared_files\config.py", line 42, in __init__   
    DEFAULT_CONFIG = asdict(DefaultConfig())
                            ^^^^^^^^^^^^^^^
  File "<string>", line 3, in __init__
  File "C:\Users\sterg\miniconda3\envs\self-driving-lab-demo\Lib\site-packages\covalent\_shared_files\defaults.py", line 45, in get_default_sdk_config
    or (os.environ["HOME"] + "/.config/covalent")
        ~~~~~~~~~~^^^^^^^^
  File "<frozen os>", line 679, in __getitem__
KeyError: 'HOME'

where a possible fix would be:

from os import path
home_dir = os.environ.get('HOME') or os.environ.get('USERPROFILE')
path.join(home_dir, ".config/covalent")

A workaround is:

You can set the HOME environment variable to be the same as USERPROFILE in PowerShell with the following command:

[Environment]::SetEnvironmentVariable("HOME", $env:USERPROFILE, "User")

This command sets the HOME environment variable for the current user. The change will take effect in new PowerShell sessions. If you want the change to be visible in the current session as well, you can also set it directly in the session:

$env:HOME = $env:USERPROFILE

Please note that these changes are temporary and will not persist across sessions. If you want to make a permanent change, you would need to set the environment variable at the system level, which typically requires administrative privileges.

I realize Windows isn't officially supported, but wanted to leave this here for provenance.