Question 343371 in Docker Question posted in
The official documentation can be found here.

ModuleNotFoundError: No module named 'flask' in docker run time error

type here

root@ip-172-31-40-102:~# docker logs 47821a8d780a
Traceback (most recent call last):
File "/app/app.py", line 1, in
from flask import Flask, render_template
ModuleNotFoundError: No module named ‘flask’

Use an official Python runtime as the base image

FROM python:3.9 AS backend-builder

Set the working directory in the container

WORKDIR /app

Copy the backend code into the container

COPY ./backend /app

Install Python dependencies, including Flask

RUN pip install -r requirements.txt

#——————Stage 1 Ends———————-
#——————Stage 2 Start———————
FROM python:3.9-slim-buster

Set the working directory in the container

WORKDIR /app

Copy the code from the backend-builder stage

COPY –from=backend-builder /app /app

Expose the port

EXPOSE 5000

Command to run the application

CMD ["python", "app.py"]

i want run the docker container but i not able to run contarinter i facing this error ModuleNotFoundError: No module named ‘flask’

please help to understand how to fix this issue

Tags:

2

Answers


  1. Chosen as BEST ANSWER
    0

    Use an official Python runtime as the base image

    FROM python:3.8 AS backend-builder

    Set the working directory in the container

    WORKDIR /app

    Copy the backend code into the container

    COPY ./backend /app

    Install Python dependencies, including Flask

    RUN pip install -r requirements.txt

    #------------------Stage 1 Ends---------------------- #------------------Stage 2 Start--------------------- FROM python:3.8-slim

    Set the working directory in the container

    WORKDIR /app

    Copy the code from the backend-builder stage

    COPY --from=backend-builder /app /app

    Expose the port

    EXPOSE 5000

    Command to run the application

    CMD ["python", "app.py"]

    I also change the Python versions but not working Please check my docker file it is correct or not


  2. 0

    You are only installing your requirements to the build stage, they are not available globally in the final stage.

    What you have in the final stage is only what you copy with this

    COPY --from=backend-builder /app /app

    and since you are not using a virtual env but installing requirements globally, you are not copying whatever you install with

    RUN pip install -r requirements.txt

    Solution 1

    A solution that would work for this particular Dockerfile would be to not do a multistage build, since you are not installing anything heavy in the build stage, basically only stuff that you need for the final stage anyway.

    So something like this should work:

    # Use an official Python runtime as the base image
FROM python:3.9-slim-buster

# Set the working directory in the container
WORKDIR /app

# Copy the backend code into the container
COPY ./backend /app

# Install Python dependencies, including Flask
RUN pip install -r requirements.txt

# Expose the port
EXPOSE 5000

# Command to run the application
CMD ["python", "app.py"]

    Solution 2

    If you have more stuff going on in the build stage that you don’t want in the final image, your solution needs a virtual env step so that requirements are installed locally.

    See for example https://stackoverflow.com/a/48562835/6845813.

    Login or Signup to reply.
Please signup or login to give your own answer.

Back To Top
Search