This Python web app is a simple restaurant review application built with the Flask framework. The web app stores application data in PostgreSQL with environment variables defining the connection info.
This repo was created to be built to a Docker image and run as a container instance in Azure Container Apps. For more information, see the tutorial [Deploy a Python web app on Azure Container Apps with GitHub Actions][https://learn.microsoft.com/azure/developer/python/tutorial-deploy-python-web-app-azure-container-apps-01].
This Python web app repo can also be used in other ways:
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You can run the web app locally in a virtual environment. Make sure to define .env file with environment settings.
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You can create a container locally and run it in Docker locally. You'll need Docker Desktop installed. For this scenario, set REMOTE_POSTGRESQL=1 in .env file to point to a PostgreSQL instance. See the .env.example file for details.
docker build --file Dockerfile --tag pythoncontainer:latest . docker run -it --env-file .env --publish 5000:5000/tcp pythoncontainer:latestIf you want to use PostgreSQL instance locally, add
--add-hostto the Docker command. For more information, see the Docker run command. For an example of how to do this with MongoDB, see Build and test a containerized Python web app locally. -
You can deploy the code (not a container) to App Service. For guidance on how to deploy code, see Quickstart: Deploy a Python (Django or Flask) web app to Azure App Service and Overview: Deploy a Python web app to Azure with managed identity.
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You can create a Docker image from this repo and host the container instance in Web Apps for Containers (App Service). See Overview: Containerized Python web app on Azure.
If you need an Azure account, you can create on for free.
A Django sample application with similar functionality is at https://github.com/Azure-Samples/msdocs-python-django-azure-container-apps.
The requirements.txt has the following packages:
| Package | Description |
|---|---|
| Flask | Web application framework. |
| SQLAlchemy | Provides a database abstraction layer to communicate with PostgreSQL. |
| Flask-SQLAlchemy | Adds SQLAlchemy support to Flask application by simplifying using SQLAlchemy. Requires SQLAlchemy. |
| Flask-Migrate | SQLAlchemy database migrations for Flask applications using Alembic. Allows functionality parity with Django version of this sample app. |
| pyscopg2-binary | PostgreSQL database adapter for Python. |
| gunicorn | WSGI HTTP Server for UNIX. Required for running containers locally in VS Code. |
| python-dotenv | Read key-value pairs from .env file and set them as environment variables. In this sample app, environment variables describe how to connect to the database and storage resources. Because managed identity is used no sensitive information is included in environment variables. Flask's dotenv support sets environment variables automatically from an .env file. |
| flask_wtf | Form rendering, validation, and CSRF protection for Flask with WTForms. Uses CSRFProtect extension. |
The steps to do this are covered more completely in the tutorial [Deploy a Python web app on Azure Container Apps with GitHub Actions][https://learn.microsoft.com/azure/developer/python/tutorial-deploy-python-web-app-azure-container-apps-01]. Briefly, here are the steps:
- Fork and then clone locally.
- Build a container image from the repo.
- Create a PostgreSQL Flexible Server instance.
- Create a database on the server.
- Deploy the web app container to Azure Container Apps.
- Configure continuous deployment.
See the create_resources.sh Bash script for automating the creation of these steps.