Integrating a FastAPI (Python) app within an Aspire application

Docs / Reference / Samples / Integrating a FastAPI (Python) app within an Aspire application

Integrating a FastAPI (Python) app within an Aspire application

Docs Reference Samples Integrating a FastAPI (Python) app within an Aspire application

Aspire sample

File-based AppHost

Clone, run, and explore this sample

This sample demonstrates integrating a FastAPI (Python) app and a JavaScript frontend using Aspire.

C#JavaScriptNode.jsPython

View on GitHub Browse all samples

AppHost

The entry point that composes every resource and dependency in this sample's distributed application.

View on GitHub

apphost.cs

#pragma warning disable ASPIREBROWSERLOGS001
#pragma warning disable ASPIREJAVASCRIPT001

#:sdk Aspire.AppHost.Sdk@13.4.0
#:package Aspire.Hosting.JavaScript@13.4.0
#:package Aspire.Hosting.Browsers@13.4.0-preview.1.26281.18
#:package Aspire.Hosting.Python@13.4.0
#:package Aspire.Hosting.Redis@13.4.0

var builder = DistributedApplication.CreateBuilder(args);

var cache = builder.AddRedis("cache");

var app = builder.AddUvicornApp("app", "./app", "main:app")
    .WithUv()
    .WithExternalHttpEndpoints()
    .WithReference(cache)
    .WaitFor(cache)
    .WithHttpHealthCheck("/health");

builder.AddViteApp("frontend", "./frontend")
    .WithReference(app)
    .WaitFor(app)
    .WithBrowserLogs()
    .PublishAsStaticWebsite("/api", app);

builder.Build().Run();

The sample consists of two apps:

• app: This is a simple FastAPI-based Python app that returns randomly generated weather forecast data.
• frontend: This is a Vite-based React app that renders the weather forecast data.

Prerequisites

• Aspire development environment
• Python - at least version 3.13
• Node.js - at least version 22.21.1
• .NET 10 SDK

Running the app

If using the Aspire CLI, run aspire run from this directory.

If using VS Code, open this directory as a workspace and launch the apphost.cs C# file using either the Aspire or C# debuggers.