Dockerfile build image error: Distribution contains no modules or packages for namespace package

I’m trying to build a docker image of a python project. My project has one dependency package, "my_package" which needs to be install first. It’s a namespace package.

I’m having this error when building docker image of this python project. I can pretty much install everything with RUN pip install XYZ inside Dockerfile but I’m not sure what’s the proper way to install local python namespace packages, here, my_package, properly.

I followed this exact same steps on a normal python package that is NOT A NAMESPACE PACKAGE and it works absolutely fine. Any pointers to install python namespace packages in Docker?

Dockerfile:

ARG BASE_IMAGE=ubuntu:18.04

FROM ${BASE_IMAGE} AS compile-image
ARG BASE_IMAGE=ubuntu:18.04
ENV PYTHONUNBUFFERED TRUE

RUN --mount=type=cache,id=apt-dev,target=/var/cache/apt 
    apt-get update && 
    DEBIAN_FRONTEND=noninteractive apt-get install --no-install-recommends -y 
    ca-certificates 
    g++ 
    python3.8-dev 
    python3.8-distutils 
    python3.8-venv 
    openjdk-11-jre-headless 
    curl 
    && rm -rf /var/lib/apt/lists/* 
    && cd /tmp 
    && curl -O https://bootstrap.pypa.io/get-pip.py 
    && python3.8 get-pip.py

RUN python3.8 -m venv /home/venv

ENV PATH="/home/venv/bin:$PATH"

RUN update-alternatives --install /usr/bin/python python /usr/bin/python3.8 1
RUN update-alternatives --install /usr/local/bin/pip pip /usr/local/bin/pip3.8 1

COPY my_package/* /tmp/my_package/
WORKDIR /tmp/my_package/
RUN python setup.py install

Docker build command:

$ DOCKER_BUILDKIT=1 docker build --file Dockerfile .

Error:

[+] Building 0.6s (12/12) FINISHED                                                                                                                                                 
 => [internal] load build definition from Dockerfile                                                                                                                          0.0s
 => => transferring dockerfile: 907B                                                                                                                                          0.0s
 => [internal] load .dockerignore                                                                                                                                             0.0s
 => => transferring context: 2B                                                                                                                                               0.0s
 => [internal] load metadata for docker.io/library/ubuntu:18.04                                                                                                               0.1s
 => [internal] load build context                                                                                                                                             0.0s
 => => transferring context: 3.11kB                                                                                                                                           0.0s
 => [compile-image 1/8] FROM docker.io/library/ubuntu:18.04@sha256:4bc3ae6596938cb0d9e5ac51a1152ec9dcac2a1c50829c74abd9c4361e321b26                                           0.0s
 => CACHED [compile-image 2/8] RUN --mount=type=cache,id=apt-dev,target=/var/cache/apt     apt-get update &&     DEBIAN_FRONTEND=noninteractive apt-get install --no-install  0.0s
 => CACHED [compile-image 3/8] RUN python3.8 -m venv /home/venv                                                                                                               0.0s
 => CACHED [compile-image 4/8] RUN update-alternatives --install /usr/bin/python python /usr/bin/python3.8 1                                                                  0.0s
 => CACHED [compile-image 5/8] RUN update-alternatives --install /usr/local/bin/pip pip /usr/local/bin/pip3.8 1                                                               0.0s
 => [compile-image 6/8] COPY my_package/* /tmp/my_package/                                                                                                                        0.0s
 => [compile-image 7/8] WORKDIR /tmp/my_package/                                                                                                                                0.0s
 => ERROR [compile-image 8/8] RUN python setup.py install                                                                                                                     0.4s
------
 > [compile-image 8/8] RUN python setup.py install:
#12 0.370 error in my_package setup command: Distribution contains no modules or packages for namespace package 'my_package'
------
executor failed running [/bin/sh -c python setup.py install]: exit code: 1

my_package structure:

my_package
├── [4.0K]  my_package
│   └── [  56]  __init__.py
└── [ 162]  setup.py

setup.py:

from setuptools import setup, find_packages

setup(
    name='my_package',
    version='0.0.1',
    namespace_packages=['my_package'],
    packages=find_packages()
)

__init__.py file:

__import__('pkg_resources').declare_namespace(__name__)

Answer

In your Dockerfile, you need to put :

COPY my_package/. /tmp/my_package/