Deploy a FastAPI App

FastAPI is a modern, fast (high-performance), web framework for building APIs with Python based on standard Python type hints.

This guide covers how to deploy a FastAPI app on Railway in four ways:

  1. One-click deploy from a template.
  2. From a GitHub repository.
  3. Using the CLI.
  4. Using a Dockerfile.

One-Click Deploy From a Template

Deploy on Railway

We highly recommend that you eject from the template after deployment to create a copy of the repo on your GitHub account.

Note: You can also choose from a variety of FastAPI app templates created by the community.

Deploy From a GitHub Repo

To deploy a FastAPI app on Railway directly from GitHub, follow the steps below:

  1. Fork the basic FastAPI GitHub repo.
    • If you already have a GitHub repo you want to deploy, you can skip this step.
  2. Create a New Project.
  3. Click Deploy from GitHub repo.
  4. Select the fastapi or your own GitHub repo.
    • Railway requires a valid GitHub account to be linked. If your Railway account isn't associated with one, you will be prompted to link it.
  5. Click Deploy Now.

Once the deployment is successful, a Railway service will be created for you. By default, this service will not be publicly accessible.

To set up a publicly accessible URL for the service, navigate to the Networking section in the Settings tab of your new service and click on Generate Domain.

screenshot of the deployed fastapi service showing a hello world API response on a browser

The FastAPI app is run via a Hypercorn server as defined by the startCommand in the railway.json file in the GitHub repository.

Railway makes it easy to define deployment configurations for your services directly in your project using a railway.toml or railway.json file, alongside your code.

Deploy From the CLI

  1. Install and authenticate with the CLI.
  2. Clone the forked fastapi GitHub repo and cd into the directory.
    • You can skip this step if you already have an app directory or repo on your machine that you want to deploy.
  3. Run railway init within the app directory to create a new project.
  4. Run railway up to deploy.
    • The CLI will now scan, compress and upload our fastapi app files to Railway's backend for deployment.

Use a Dockerfile

Note: If you already have an app directory or repo on your machine that you want to deploy, you can skip the first two steps.

  1. Clone the forked fastapi repo and cd into the directory.
  2. Delete the railway.json file.
  3. Create a Dockerfile in the fastapi or app's root directory.
  4. Add the content below to the Dockerfile:
    # Use the Python 3 alpine official image
    # https://hub.docker.com/_/python
    FROM python:3-alpine
    
    # Create and change to the app directory.
    WORKDIR /app
    
    # Copy local code to the container image.
    COPY . .
    
    # Install project dependencies
    RUN pip install --no-cache-dir -r requirements.txt
    
    # Run the web service on container startup.
    CMD ["hypercorn", "main:app", "--bind", "::"]
  5. Either deploy via the CLI or from GitHub.

Railway automatically detects the Dockerfile, and uses it to build and deploy the app.

Note: Railway supports also deployment from public and private Docker images.

Next Steps

Explore these resources to learn how you can maximize your experience with Railway:


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