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Why can't docker compose find uvicorn module

I am new to docker and was trying to dockerize my fastapi application.
I built a Dockerfile shown below
# syntax=docker/dockerfile:1
FROM python:3.8-slim-buster
WORKDIR /app
COPY requirements.txt requirements.txt
RUN apt-get update
RUN apt-get -y install libpq-dev gcc
RUN apt-get -y install libnss3-tools
RUN apt-get -y install curl
RUN curl -LJO https://github.com/FiloSottile/mkcert/releases/download/v1.4.4/mkcert-v1.4.4-linux-amd64
RUN mv mkcert-v1.4.4-linux-amd64 mkcert
RUN chmod +x mkcert
RUN ./mkcert -install
RUN ./mkcert -cert-file cert.pem -key-file key.pem 0.0.0.0 localhost 127.0.0.1 ::1
RUN pip3 install -r requirements.txt
COPY . .
CMD ["python3.8", "-m", "uvicorn", "main:app", "--host=0.0.0.0", "--ssl-keyfile=./key.pem", "--ssl-certfile=./cert.pem"]
and ran the containers and they all worked. But when I try to combine the containers with docker compose its tells me can't find uvicorn module even when it's in the requirements.txt file .
Here is a snippet of my docker compose file containing the server service.
services:
server:
container_name: server
image: python:3.8-slim-buster
command: ["python3.8", "-m", "uvicorn", "main:app", "--host=0.0.0.0", "--ssl-keyfile=./key.pem", "--ssl-certfile=./cert.pem"]
ports:
- 8000:8000
working_dir: /app
I have tried using changing the command part of the server service in docker compose to
command: bash "python3.8 -m uvicorn main:app --host=0.0.0.0 --ssl-keyfile=./key.pem --ssl-certfile=./cert.pem"
didn't work.
changed it to
command: sh -c "python3.8 -m uvicorn main:app --host=0.0.0.0 --ssl-keyfile=./key.pem --ssl-certfile=./cert.pem"
didn't work.
I removed the command totally it still didn't work, keeps showing
server | /usr/local/bin/python3.8: No module named uvicorn
server exited with code 1

The image you use in the docker compose is not the one previously built in the Dockerfile but a basic Python image.
You could build the image from your Dockerfile
docker build . -t fastapi
then modify your docker-compose.yml file with something like this
services:
api:
image: fastapi
ports:
- "8000:8000"
then run docker compose
docker-compose -f docker-compose.yml up

Docker Max retries exceeded with url: /assets

I'm a bit new to docker and I'm messing around with it. I currently have a server being ran on port 5000 in another container. This server is being ran with express and uses JavaScript. I'm trying to send requests to that server with python. I tried using both localhost:5000 and 127.0.0.1:5000 but neither of these seems to work. What can I do? I noticed if I run the python code without docker it works perfectly fine.
Python Docker File:
FROM ubuntu:latest
RUN apt update
RUN apt install python3 -y
RUN apt-get install -y python3-pip
WORKDIR /usr/app/src
COPY . .
RUN pip install discum
RUN pip install python-dotenv
EXPOSE 5000
CMD ["python3", "./src/index.py"]
JavaScript Docker File:
FROM node:latest
WORKDIR /usr/src/app
COPY package.json ./
RUN npm install
COPY . .
CMD ["npm", "start"]

You could create a network between the to containers using --net look at this answer How to get Docker containers to talk to each other while running on my local host?
Another way, and my preferred way, is to use docker-compose and create networks between your containers.

Use Service Name and Port is always the best.
So if you have a docker file like the below you could use the URL http://client:5000
version: 3.8
services:
client:
image: blah
ports:
- 5000:5000

gunicorn: command not found with Docker and Dash Python

I've recently developped a Dash Python Dashboard web app using Docker and I want to deploy it. (it's working perfectly in development).
Since Flask is not stable for deployment, I decided to use gunicorn instead.
I've added gunicorn in the requirements.txt.
I've replaced python app.py by gunicorn app:server in the initial script. And I've rebuilt the docker-compose to install the new image.
But I get the error gunicorn: command not found.
It seems that there is an issue with the path of gunicorn but I don't know how to solve it.
Here is the Dockerfile of the container named container_api:
FROM archlinux:latest
COPY api/requirements.txt ./
RUN pacman-db-upgrade \
&& pacman -Syyu --noconfirm \
&& pacman -S python --noconfirm \
&& pacman -S python-pip --noconfirm \
&& pip install --no-cache-dir -r requirements.txt
WORKDIR /app
CMD chmod a+x entrypoint.sh && ./entrypoint.sh
Here is the entrypoint.sh:
#!/bin/bash
gunicorn app:server
I specify that I have a shared volume named app between the host and the container. So entrypoint.sh is accessible by the container.
The log of the container is displaying:
container_api | ./entrypoint.sh: line 3: gunicorn: command not found
I also add the docker-compose file to see how the containers are built:
version: "3"
services:
worker:
build:
dockerfile: ./worker/Dockerfile
container_name: container_worker
environment:
- PYTHONUNBUFFERED=1
volumes:
- ./api:/app/
- ./worker:/app2/
api:
build:
dockerfile: ./api/Dockerfile
container_name: container_api
volumes:
- ./api:/app/
- /var/run/docker.sock:/var/run/docker.sock
ports:
- "${API_PORT}:8050"
depends_on:
- worker
What is weird is that when I was using Flask as development server, I had no problem using the packages installed via requirement.txt in my Dash app. It seems that using a package outside the Dash app (in the entrypoint script) is making problem. Do you know why?
I hope I was clear in my explanations. Thank you for your help,

Ok it seems I discovered why I have this problem.
My development machine is a distant server and I'm developping on it via Vscode on my local machine with remote-ssh extension. I checked the Path and it's actually something weird with some vscode elements inside.
So I tried launching the docker without Vscode and it's working. I really don't know how to fix this issue but I will find out on vscode posts.
Thank you very much for your help

Can't open localhost in the browser on port given in docker-compose

I am trying to build and run django application with docker and docker-compose.
docker-compose build example_app and docker-compose run example_app run without errors, but when I go to http://127.0.0.1:8000/ page doesn't open, I'm just getting "page is unavailable" error in the browser.
Here is my Dockeffile, docker-compose.yml and project structure
Dockerfile
FROM python:3.9-buster
RUN mkdir app
WORKDIR /app
COPY ./requirements.txt /app/requirements.txt
COPY ./requirements_dev.txt /app/requirements_dev.txt
RUN pip install --upgrade pip
RUN pip install -r /app/requirements.txt
docker-compose.yml
version: '3'
services:
example_app:
image: example_app
build:
context: ../
dockerfile: ./docker/Dockerfile
command: bash -c "cd app_examples/drf_example && python manage.py runserver"
volumes:
- ..:/app
ports:
- 8000:8000
project structure:
──app
──app_examples/drf_example/
────manage.py
────api
────drf_example
──requirements.txt
──requirements_dev.txt
──docker/
────docker-compose.yml
────Dockerfile

By default, Django apps bind to 127.0.0.1 meaning that they'll only accept connections from the local machine. In a container context, the local machine is the container, so your app won't accept connections from outside the container.
To get it to accept connections from anywhere, you add the bind address to the runserver command. In your case, you'd change the command in your docker-compose.yml file to
command: bash -c "cd app_examples/drf_example && python manage.py runserver 0.0.0.0:8000"

you need to expose port 8000 in your Docker file
FROM python:3.9-buster
EXPOSE 8000
RUN mkdir app
WORKDIR /app
COPY ./requirements.txt /app/requirements.txt
COPY ./requirements_dev.txt /app/requirements_dev.txt
RUN pip install --upgrade pip
RUN pip install -r /app/requirements.txt

Unable to run Flask App using Docker in Windows-10

I've installed and configured docker (as per documentation) and I am trying to build a flask application using tiangolo/uwsgi-nginx-flask:python3.8. I've built a hello-world application, and have tested it locally by running python manage.py and the application runs successfully. Link to full Code-File.
My docker version and installation is as below:
Dockerfile:
FROM tiangolo/uwsgi-nginx-flask:python3.8
ENV INSTALL_PATH /usr/src/helloworld
RUN mkdir -p $INSTALL_PATH
# install net-tools
RUN apt-get update \
&& DEBIAN_FRONTEND=noninteractive apt-get install -y \
net-tools \
&& apt-get clean \
&& rm -rf /var/lib/apt/lists/*
# set working directory
WORKDIR $INSTALL_PATH
# setup flask environment
# install all requirements
COPY requirements.txt requirements.txt
RUN pip install -r requirements.txt
# copy all files and folder to docker
COPY . .
# run the application in docker environment
CMD [ "python", "./manage.py" ]
I built the application with docker build --tag hello-world:test . and running the application as: docker run -d -p 5000:5000 hello-world:test successfully.
However, I'm unable to open the application in localhost:5000 or 0.0.0.0:5000 or any other port. The application is running, as I can see it from the CLI:
But, from browser the page is not reachable:
The question mentions to check the IP address:
docker inspect -f "{{ .NetworkSettings.Networks.nat.IPAddress }}" hungry_engelbart
>> <no value>
Found another solution at this link, but docker-machine is currently deprecated.
I'm new to docker, but I have tried to run the same thing following this tutorial, but faced similar issues.

Finally, I am able to solve this. I had to configure a new inbound rules under Windows Firewall > Advanced Settings > Inbound Rules > New Inbound Rules. Create a new rule that will allow a range of local IP addresses, which in my case was 198.168.0.1:198.168.0.100. Finally, you need to run the application at 0.0.0.0 as pointed by #tentative in the comments. :)