Install Numpy Requirement in a Dockerfile. Results in error

Question

I am attempting to install a numpy dependancy inside a docker container. (My code heavily uses it). On building the container the numpy library simply does not install and the build fails. This is on OS raspbian-buster\/stretch. This does however work when building the container on MAC OS.

FROM python:3.6
ENV PYTHONUNBUFFERED 1
ENV APP /app
RUN ln -snf /usr/share/zoneinfo/$TZ /etc/localtime && echo $TZ > /etc/timezone
RUN mkdir $APP
WORKDIR $APP
ADD requirements.txt .
RUN pip install -r requirements.txt
COPY . .

Answer 1

To use Numpy on python3 here, we first head over to the official documentation to find what dependencies are required to build Numpy.

Mainly these 5 packages + their dependencies must be installed:

1. Python3 - 70 mb
2. Python3-dev - 25 mb
3. gfortran - 20 mb
4. gcc - 70 mb
5. musl-dev -10 mb (used for tracking unexpected behaviour/debugging)

An POC setup would look something like this -

Dockerfile:

FROM gliderlabs/alpine
ADD repositories.txt /etc/apk/repositories

RUN apk add --no-cache --update \
    python3 python3-dev gcc \
    gfortran musl-dev

ADD requirements-pip.txt .
RUN pip3 install --upgrade pip setuptools && \
    pip3 install -r requirements-pip.txt

ADD . /app
WORKDIR /app
ENV PYTHONPATH=/app/
ENTRYPOINT python3 testscript.py

repositories.txt

http://dl-5.alpinelinux.org/alpine/v3.4/main

requirements-pip.txt

numpy

testscript.py

import numpy as np

def random_array(a, b):
    return np.random.random((a, b))

a = random_array(2,2)
b = random_array(2,2)
print(np.dot(a,b))

To run this - clone alpine , build it using "docker build -t gliderlabs/alpine ."

Build and Run your Dockerfile

docker build -t minidocker .
docker run minidocker

Output should be something like this-

[[ 0.03573961 0.45351115]
[ 0.28302967 0.62914049]]

Here's the git link , if you want to test it out

Answer 2

From the error logs, it does not seems that it from numpy. but you can install numpy before the requirment.txt and verify if it's working.

FROM python:3.6
RUN pip install numpy==1.14.3

Build

docker build -t numpy .

Run and Test

docker run numpy bash -c "echo import numpy as np > test.py ; python test.py"

So you will see no error on import.

or You can try numpy as an alpine package

FROM python:3-alpine3.9
RUN apk add --no-cache py3-numpy

Or better to post the requirement.txt.

Answer 3

I had lot of trouble with this issue using FROM python:3.9-buster and pandas.

My requirements.txt had the python-dev-tools, numpy and pandas, along with other packages.

I always got something like this when attempting to build :

preluded by:

and by:

Following hints by Adiii in this thread, I did some debug and found out that this actually works and builds a perfectly running container:

RUN pip3 install NumPy==1.18.0

RUN pip3 install python-dev-tools

RUN pip3 install pandas

RUN pip3 install -r requirements.txt

So, giving a specific RUN layer to the pip3 installing pandas solved the problem!

Answer 4

FROM python:slim
CMD pip install numpy