Getting Started with Docker and Flask

Last update: Oct 08, 2021

Overview

Getting-Started-with-Docker-and-Flask

Introduction

Docker makes it easier, simpler and safer to build, deploy and manage applications in a docker container. This article will help you get a detailed understanding of;

What is docker?
Why use Docker?
What is a docker image?
What is a docker container?
Dockerizing a flask application

What is Docker?

Docker is an open source containerization platform for developing, shipping and running applications.

Docker packages software into standardized units called containers. Containers have everything the software needs to run including libraries, system tools, code, and runtime.

More about what docker is

Why use Docker?

Responsive deployment and scaling.
Faster And Consistent Delivery Of Applications.

Docker image.

Image is a read-only template with instruction for creating containers. Docker images can be considered as the blueprint of the entire application environment that you create.

Docker container.

A Docker container is a virtualized run-time environment where users can isolate applications from the underlying system.
Containers are compact, portable units in which you can start up an application quickly and easily.
Docker containers contains all the essential things required to run an application like code, runtime, system tools, system libraries, and settings.

Dockerizing a flask application

File structure and setup

\-- dockerExample
    |-- app.py
    |-- Dockerfile
    |-- requirements.txt
   \-- templates
        |-- index.html

First I created a simple Flask application and added the following code to app.py.

from flask import Flask,render_template
app=Flask(__name__)

@app.route('/')
def home():
    return render_template('index.html')

if __name__==('__main__'):
    app.run(debug=True)

Check how to create a simple flask application

Add the following code to index.html

>
<html>
<head>
<title>Getting started with Dockertitle>
head>
<body>
<p>This is my Dockerfilep>

body>

Now we need to dockerize the flask application by creating a Dockerfile Dockerfileis a text document that contains all the commands a user could call on the command line to assemble an image.

Add the following code to docker;

FROM python:3.9.6
COPY . /doc
COPY ./requirements.txt /doc/requirements.txt
WORKDIR /doc
EXPOSE 5000:5000
RUN pip install -r requirements.txt
CMD ["python","app.py"]

FROM keyword is used to specify the base image to be used. We'll be making use of a python base image.
WORKDIR defines the main directory of operations.
EXPOSE informs Docker that the container listens on the specified network ports at runtime.
RUN is used to install the project’s dependencies.
CMD provide defaults for an executing container.

We can now build our image with the docker build command as shown below;

docker image build -t docker_example .

Once the build process is done, we can run the application with the docker run command as shown below;

docker run -p 5000:5000 docker_example

Getting Started with Docker and Flask

Related tags

Overview

Getting-Started-with-Docker-and-Flask

Introduction

What is Docker?

Why use Docker?

Docker image.

Docker container.

Dockerizing a flask application

File structure and setup

Owner

Phylis Jepchumba

A simple web application built using python flask. It can be used to scan SMEVai accounts for broken pages.

Curso Desenvolvimento avançado Python com Flask e REST API

Forum written for learning purposes in flask and sqlalchemy

A simple application builder. Made with python.

Small and simple gravatar usage in Flask.

Small flask based opds catalog designed to serve a directory via OPDS

Making a simple app using React, Flask and MySQL.

Source code for backpainfree.org - a Q&A platform similar to StackOverFlow

WebSocket support for Flask

Flask Application Structure with MongoDB

A Flask extension that enables or disables features based on configuration.

This repo contains the Flask API to expose model and get predictions.

Flask app + (html+css+ajax) contain ability add employee and place where employee work - plant or salon

An python flask app with webserver example

A python package for integrating ripozo with Flask

Map Matching & Weight Completion service - Java (Springboot) & Python(Flask)

This is a simple python flask web app that implements geometric calculations for three shapes given the user's input for radius and height. It is recommended this app be run using a python virtual environment, but not necessary for success. Unit tests are also included.

Sample Dockerized flask app deployed on Kubernetes on Azure using AKS

Flask-app scaffold, generate flask restful backend

Flask Sitemapper is a small Python 3 package that generates XML sitemaps for Flask applications.