maaszaxxs / local_env Goto Github PK

In this project, you will learn how to deploy a simple flask application to a docker container. When running the container will supply a url for displaying hello world.

You will find a Makefile, with instructions to setup a virtual environment venv and install the dependencies from the requirements.txt. The flask package will be installed. The Makefile helps use run the make commands that bundle commands together.

Use the command make setup to run python3 -m venv venv that creates a virtual environment venv. To activate the virtual environment run source venv/bin/activate, the terminal should change to (venv) meaning that you are inside the virtual environment. Install the dependencies using the make install command that runs pip install --upgrade pip &&\ pip install -r requirements.txt. The first pip install upgrades pip (the package installer for python) and the second pip install installs the packages mentioned in requirements.txt.

Build the docker image using the Dockerfile. It contains the docker image pull in the FROM python:3.7.13-alpine3.16 that loads an alpine 3.16 image. The WORKDIR /app sets the working directory. The COPY . /flask_app/app.py /app/ copies app.py from flask_app directory to the working directory. The RUN installs dependencies for upgrading pip and from requirements.txt. EXPOSE 8080 exposes port 8080 to the external environment. The CMD ["python", "app.py"] runs app.py when the container is running with a python interpreter.

Run the command docker build -t [tag_name] . to build a docker image. Replace the tag_name with a suitable tag for the image. Verify that your image is created with a docker image ls command that list docker images.

Run the command docker run -it [tag_name] to start the container. It should display:

* Serving Flask app 'app' (lazy loading)
* Environment: production
  WARNING: This is a development server. Do not use it in a production deployment.
  Use a production WSGI server instead.
* Debug mode: on
* Running on all addresses (0.0.0.0)
  WARNING: This is a development server. Do not use it in a production deployment.
* Running on http://127.0.0.1:8080
* Running on http://172.17.0.2:8080 (Press CTRL+C to quit)
* Restarting with stat
* Debugger is active!
* Debugger PIN: 112-478-073

Use the second url starting with 172, when you test on a browse it should display Hello, World!