Step-by-Step Guide to Building and Running a Flask Server on Docker

"Setting Up a Backend Server with Flask in a Docker Environment"

"Creating a Docker Image for Flask Application"

"Step-by-Step Guide to Building and Running a Flask Server on Docker"

"Easy Backend Server Setup with Flask and Docker"

"How to Deploy a Flask Server using Docker for Development"

 

Today, I'll try to set up a backend server using Flask in a Docker environment, and I'll make it easy for you to follow along. For this, I'll be using VS Code and the terminal for my practical work.

 

 

Create Flask App.py

from flask import Flask

app = Flask(__name__)

@app.route('/')
def hello():
    return 'Hello Flask World'
    
if __name__ == '__main__':
    app.run()

Please create an app.py file in the parent directory with the following content.

 

Please write a Dockerfile

 

This file is used to build a Docker image

FROM python:3.9

COPY requirements.txt requirements.txt
RUN pip install -r requirements.txt

COPY . /app

WORKDIR /app

CMD ["python3", "-m", "flask", "run", "--host=0.0.0.0"]

Create a new file called Dockerfile and include the following content:

To briefly explain the contents of the script:

• FROM python:3.9 : specifies which virtual environment engine to use when Docker runs as a container
• COPY : copies local resources to the resources Docker will upload (similar to the cp command in Linux)
• RUN : executes commands during Docker build
• WORKDIR : sets the directory path when the Docker virtual environment is launched
• CMD : specifies the command to be executed when the Docker virtual environment is launched

This file creates a Docker image based on Python 3.9. The image is configured to work in the /app directory, and the requirements.txt file with the necessary libraries is copied. Then, app.py is executed to start the Flask server.

 

 

Write a requirements.txt file

docker build -t flask-server .

Save the image with the name 'flask-server'

 

Run the Docker container

 

docker run -p 5000:5000 flask-server

Run the built Docker and check if it's properly uploaded at the address 127.0.0.1:5000.

That's it for today's tutorial!