How to provide sys.path in python script to docker file - python-2.7

Question

I have added sys.path
sys.path.append("C:\\Program Files\\FME\\fmeobjects\\python27")
in python script which works well when I run the script. I am not trying to dockerize the script. My docker script is
FROM python:2.7-alpine
ADD test1.py /
CMD [ "python", "./test1.py" ]
it builds the image but while running the image it gives error
Traceback (most recent call last):
File "./test1.py", line 17, in <module>
import fmeobjects
ImportError: No module named fmeobjects

Answer 1

It seems like your script cannot import fmeobjects because it is outside the container. Try adding the import for fmeobjects in the directory you ADD.

Answer 2

What does test1.py do?
If fmeobjects is a package / module, you need to add as mentioned above to the environment of the image.
You can also set up a distutils for it and you can pip install it in the image.
Effectively, as currently constructed, you're trying to import a package in your script that does not exist because it has not been installed.

Answer 3

Even for small standalone applications, using the standard distribution tools streamlines this process significantly. This is doubly true if you have colleagues that might have different usernames, directory layouts, or even operating systems. Don't manually edit sys.path in your script.
You should write a setup.py file that uses the setuptools library. Complete documentation is here but a minimal example might look like:
#!/usr/bin/env python
from setuptools import setup, find_packages
setup(
name="fmeobjects",
version="0.1",
packages=find_packages(),
entry_points={
'console_scripts': [
'fmeobjects = fmeobjects.main:main'
]
}
)
For development use, create a virtual environment and install your package in it.
virtualenv vpy
. vpy/bin/activate
pip install -e .
The . activate line sets some additional environment variables for you, including adding the virtual environment to your $PATH. (source is an equivalent vendor extension that works in some shells; . is part of the standard and works even in minimal shells like what you get in Alpine or Busybox installations.) You can now run fmeobjects at the shell prompt, which will call the main() function in fmeobjects/main.py (see the entry_points declaration).
You have a couple of options of how to install this in Docker. Probably the most straightforward is to simply import your source tree and install it. Since Docker containers provide isolated filesystems and generally do only one thing, there's not much point in supporting an isolated Python installation within that; just install your package into the global Python.
FROM python:2.7
WORKDIR /usr/src/app
COPY . .
RUN pip install .
CMD ["fmeobjects"]
(If your virtual environment is in your source tree, you can add vpy to a .dockerignore file to cause it to not be copied, saving time and space.)