/azure-fastapi-app-service

sample app

Primary LanguageBicepMIT LicenseMIT

Azure FastAPI App Service Sample

Note: This is currently a work in progress. The project is being developed to demonstrate the deployment of a FastAPI application on Azure App Service with various features and configurations, and is not yet complete nor fully deployable.

A Python FastAPI application that displays environment variables in an HTML table format, deployed as a Linux container on Azure App Service. The application is secured with Azure Entra ID authentication and integrates with Azure Monitor for logging.

Project Overview

This application provides a simple web interface to view all environment variables available to the running container. It includes:

  • HTML table display of all environment variables
  • Parsing of FEATURE_FLAGS environment variable as a comma-delimited list
  • Health check endpoint
  • Environment-specific logging configuration
  • Azure Key Vault integration using Managed Identity
  • Azure Monitor integration for logging and monitoring

Local Development Setup

Prerequisites

  • Docker and Docker Compose
  • Python 3.x (for local development outside of Docker)
  • Azure CLI (for deployment)

Running Locally

  1. Clone this repository:

    git clone <repository-url>
cd azure-fastapi-app-service

  2. Create a .env file for local environment variables:

    echo "FEATURE_FLAGS=local_dev,debug" > .env

  3. Run the application using Docker Compose:

    docker-compose up

  4. Access the application:

Deployment

Prerequisites

  • Azure subscription
  • Azure CLI installed and logged in
  • Docker installed

Deployment Steps

  1. Initialize the infrastructure:

    make init

  2. Deploy to the desired environment:

    # For development
make deploy-dev

# For staging
make deploy-staging

# For production
make deploy-prod

  3. To deploy with custom feature flags:

    make deploy ENV=<environment> FEATURE_FLAGS="flag1,flag2,flag3"

  4. To update dependencies to latest versions:

    make update-deps

  5. To clean up resources:

    make clean

Project Structure

/
├── src/               # Application source code
│   ├── main.py        # FastAPI application
│   ├── requirements.txt # Python dependencies
│   └── templates/     # HTML templates
├── infra/             # Bicep templates
│   ├── main.bicep     # Main infrastructure template
│   └── modules/       # Modularized Bicep components
├── Dockerfile         # Container definition
├── docker-compose.yml # Local development setup
├── Makefile           # Deployment automation
├── README.md          # This file
└── spec.md            # Technical specification

Configuration

Environment Variables

Variable Description Default
FEATURE_FLAGS Comma-delimited list of feature flags ""
LOG_LEVEL Logging level (DEBUG, INFO, WARNING) Based on environment
AZURE_KEY_VAULT_URI URI of Azure Key Vault Set by App Service
APPINSIGHTS_INSTRUMENTATIONKEY Azure Application Insights key Set by App Service

Environment-specific Settings

  • Development: DEBUG logging, feature flags: "dev_mode,debug_api"
  • Staging: INFO logging, feature flags: "metrics,api_logging"
  • Production: WARNING logging, no default feature flags

Authentication

Authentication is handled by Azure App Service using Entra ID. The Bicep templates configure the App Service to require authentication with specific tenant ID and user role settings.

Key Vault Integration

The application uses the Managed Identity assigned to the App Service to access secrets in Key Vault. No credentials are stored in the application code or configuration.

Makefile Commands

  • make help - Display available commands
  • make init - Create resource group and ACR
  • make build - Build Docker container
  • make push - Push container to ACR
  • make deploy-infra - Deploy Azure resources with Bicep
  • make deploy-app - Configure App Service to use the container
  • make deploy - Full deployment process
  • make deploy-dev - Deploy to development environment
  • make deploy-staging - Deploy to staging environment
  • make deploy-prod - Deploy to production environment
  • make update-deps - Update dependencies in requirements.txt
  • make clean - Remove resource group and all resources