Docker Python CLI App

Python simple CLI app in Docker container.

Run the Application

1. Build the Docker image:

   docker build -t goodbuy-app .

2. Run the Docker container:

    docker run goodbuy-app

Docker Python CLI Tutorial

Certainly! Creating a simple Dockerized Python CLI application involves a few steps. Below, I'll guide you through creating the Python app goodbuy.py and setting up a Docker container using a Python Alpine image for a lightweight deployment. Here's how you can do it:

1. Create Your Python Application

First, let's create the Python CLI application you mentioned, goodbuy.py. This script will be very basic, but you can customize it as needed later.

goodbuy.py:

#!/usr/bin/env python3

def main():
    print("Goodbye! Have a great day!")

if __name__ == "__main__":
    main()

This script simply prints a farewell message when executed.

2. Write the Dockerfile

Next, you will create a Dockerfile that specifies how to build the Docker image for your application. Using the Python Alpine image is a great choice for keeping the image size small.

Dockerfile:

# Use an official Python runtime as a parent image
FROM python:3.9-alpine

# Set the working directory in the container
WORKDIR /usr/src/app

# Copy the current directory contents into the container at /usr/src/app
COPY . .

# Make the script executable
RUN chmod +x goodbuy.py

# Define the command to run your script
CMD [ "python", "./goodbuy.py" ]

This Dockerfile does the following:

• Starts with the Python 3.9 image based on Alpine Linux for a minimal footprint.
• Sets the working directory inside the container to /usr/src/app.
• Copies everything from your project directory (where the Dockerfile is located) into the container.
• Makes your goodbuy.py script executable.
• Specifies the command to run your script when the container starts.

3. Build and Run Your Docker Container

With your goodbuy.py and Dockerfile ready, you can now build and run your Docker container. First, ensure Docker is installed and running on your system.

Open a terminal and navigate to the directory containing your Dockerfile and goodbuy.py script. Then, execute the following commands:

# Build your Docker image
docker build -t goodbuy-app .

# Run your Docker container
docker run goodbuy-app

The docker build command builds the Docker image from your Dockerfile, tagging it (-t) with the name goodbuy-app. The docker run command then starts a container based on this image. When the container runs, it should execute your Python script and print the farewell message.

This setup provides a basic foundation for a Dockerized Python CLI application. You can expand your Python script with more functionality and adjust the Dockerfile as needed for additional dependencies or configuration.