Create and Run a Container for a Python Web Application.

Task: Create and Run a Docker Container for a Python Web Application

Description: You are tasked with creating and running a Docker container for a simple Python web application using Flask. The application should display a "Hello, Docker!" message when accessed through a web browser.

Steps:

1. Create a Directory Structure: Create a directory for your project and navigate into it:

   mkdir docker-python-app

   cd docker-python-appz

2. Create the Python Web Application: Create a Python file named app.py with the following code:

   from flask import Flask

   app = Flask(__name__)

   @app.route('/')

   def hello():

   return "Hello, Docker!"

   if __name__ == '__main__':

   app.run(host='0.0.0.0', port=8080)

3. Create a Dockerfile:

   Create a file named Dockerfile (without any file extension) in the same directory with the following content:

   # Use an official Python runtime as a parent image

   FROM python:3.8-slim

    

   # Set the working directory to /app

   WORKDIR /app

    

   # Copy the current directory contents into the container at /app

   COPY . /app

    

   # Install any needed packages specified in requirements.txt RUN pip install --no-cache-dir -r requirements.txt

   # Make port 8080 available to the world outside this container

   EXPOSE 8080

    

   # Define environment variable

   ENV NAME World

    

   # Run app.py when the container launches

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

4. Create a Requirements File: Create a file named requirements.txt with the following content:

   Flask==2.0.1

5. Build the Docker Image: Build the Docker image using the following command:

   docker build -t python-docker-app .

6. Run the Docker Container: Run the Docker container from the image you built:

   docker run -p 8080:8080 python-docker-app

7. Access the Web Application: Open a web browser and navigate to http://localhost:8080 to see the "Hello, Docker!" message.

Remember that this is a basic example, and there are many additional considerations and optimizations you can apply when working with Docker containers in real-world scenarios.