Get python-dotenv "OSError: Starting path not found" in a python package install using `setup.py install`

Question

Problem description

When working with environment vars, a .env file is used for development via python-dotenv. When the app is distributed (and so installed using setuptools), the env vars are provided by an other way of course.

The problem is after installing in a virtual env via setup.py install, launching a script that uses load_dotenv raises the error OSError: Starting path not found:

Traceback (most recent call last):
  File "/home/dev/testpkg/venv/bin/run", line 11, in <module>
    load_entry_point('testpkg==0.0.1', 'console_scripts', 'run')()
  File "/home/dev/testpkg/venv/lib/python3.8/site-packages/pkg_resources/__init__.py", line 489, in load_entry_point
    return get_distribution(dist).load_entry_point(group, name)
  File "/home/dev/testpkg/venv/lib/python3.8/site-packages/pkg_resources/__init__.py", line 2852, in load_entry_point
    return ep.load()
  File "/home/dev/testpkg/venv/lib/python3.8/site-packages/pkg_resources/__init__.py", line 2443, in load
    return self.resolve()
  File "/home/dev/testpkg/venv/lib/python3.8/site-packages/pkg_resources/__init__.py", line 2449, in resolve
    module = __import__(self.module_name, fromlist=['__name__'], level=0)
  File "/home/dev/testpkg/venv/bin/run.py", line 4, in <module>
    __import__('pkg_resources').run_script('testpkg==0.0.1', 'run.py')
  File "/home/dev/testpkg/venv/lib/python3.8/site-packages/pkg_resources/__init__.py", line 666, in run_script
    self.require(requires)[0].run_script(script_name, ns)
  File "/home/dev/testpkg/venv/lib/python3.8/site-packages/pkg_resources/__init__.py", line 1469, in run_script
    exec(script_code, namespace, namespace)
  File "/home/dev/testpkg/venv/lib/python3.8/site-packages/testpkg-0.0.1-py3.8.egg/EGG-INFO/scripts/run.py", line 7, in <module>
  File "/home/dev/testpkg/venv/lib/python3.8/site-packages/dotenv/main.py", line 336, in load_dotenv
    dotenv_path = find_dotenv()
  File "/home/dev/testpkg/venv/lib/python3.8/site-packages/dotenv/main.py", line 300, in find_dotenv
    for dirname in _walk_to_root(path):
  File "/home/dev/testpkg/venv/lib/python3.8/site-packages/dotenv/main.py", line 257, in _walk_to_root
    raise IOError('Starting path not found')
OSError: Starting path not found

The solution to this problem would be to use pip install . which works fine.

I know that eggs are deprecated, but I would like to know if there is a solution to make this work using setup.py install?

Full example

There's a minimal project to reproduce the error.

A fresh project installed in a virtual environment using Python 3.8 and a src-layout model.

The project tree

root_project_dir/
 |--- .env
 |--- setup.py
 |--- src/
       |--- run.py
       |--- pkg/
             |--- __init__.py
             |--- mod.py

Of course the .env is only for local testing and is not aimed to be distributed.

The run.py script's main() function is the entry point of the app.

setup.py content

from setuptools import setup, find_namespace_packages

setup(
    name='testpkg',
    version='0.0.1',
    install_requires=["python-dotenv"],
    packages=find_namespace_packages(where='src'),
    package_dir={"": "src"},
    scripts=['src/run.py'],
    entry_points={
        'console_scripts': [
            'run = run:main',
        ]
    }
)

run.py content

import os

from dotenv import load_dotenv

from pkg.mod import Mod

load_dotenv()

VAR = os.getenv('VAR')


def main():
    m = Mod(VAR)
    m.run()


if __name__ == "__main__":
    main()

mod.py content

class Mod(object):
    def __init__(self, var):
        print("init with var:", var)

    def run(self):
        print("Ok I ran!")

.env content

VAR=some text

Reproduce the problem

Install and run

Create and activate a virtual env:

python3 -m venv venv
source ./venv/bin/activate

test locally

Run locally works with the .env retrieved:

(venv) root_project_dir/$ pip install python-dotenv
(venv) root_project_dir/$ python src/run.py
init with var: some text
Ok I ran!

install the package and run

First install:

(venv) root_project_dir/$ python setup.py install
...
Using /home/dev/testpkg/venv/lib/python3.8/site-packages
Finished processing dependencies for testpkg==0.0.1

Then run the entry point generates the error:

(venv) root_project_dir/$ run
Traceback (most recent call last):
  File "/home/dev/testpkg/venv/bin/run", line 11, in <module>
...
  File "/home/dev/testpkg/venv/lib/python3.8/site-packages/dotenv/main.py", line 300, in find_dotenv
    for dirname in _walk_to_root(path):
  File "/home/dev/testpkg/venv/lib/python3.8/site-packages/dotenv/main.py", line 257, in _walk_to_root
    raise IOError('Starting path not found')
OSError: Starting path not found

At line 300, path value is /home/dev/testpkg/venv/lib/python3.8/site-packages/testpkg-0.0.1-py3.8.egg/EGG-INFO/scripts whereas /home/dev/testpkg/venv/lib/python3.8/site-packages/testpkg-0.0.1-py3.8.egg is of course a file.

Again, the solution to this problem would be to use pip install . which works fine.

I know that eggs are deprecated, but I would like to know if there is a solution to make this work using setup.py install?

Answer 1

Removing .pytest_cache and __pycache__ folders might help. The problem occured to me after I renamed parent folder.

Answer 2

If other users have the same issue and just want to make it working, as I said, a way to solve this problem is to use pip instead of python setup.py install:

(venv) pip install .

And voilà!

As you can see in this answer, eggs are deprecated and replaced by using pip/wheels.