App Engine

Google App Engine⚑

Deploy a Fastapi App in Google App engine⚑

This guide will help you deploy a FastAPI application on Google App Engine.

Prerequisites⚑

• A Google Cloud account
• Google Cloud SDK installed on your machine
• A FastAPI application

Step 1: Prepare Your FastAPI Application⚑

Your FastAPI application is ready to go. Here's the main.py for reference:

from fastapi import FastAPI
import uvicorn

app = FastAPI()

@app.get('/')
async def root():
    return {'message': 'Hello Duke'}

@app.get('/add/{num1}/{num2}')
async def add(num1: int, num2: int):
    '''Add two numbers together'''

    total = num1 + num2
    return {'total': total}

if __name__ == '__main__':
    uvicorn.run(app, port=8080, host='0.0.0.0')

Step 2: Create app.yaml File⚑

Next, you'll need to create an app.yaml file in the root directory of your project. This file configures your App Engine application's settings.

Here's an example app.yaml file:

runtime: python39  # Use the Python 3.9 runtime
instance_class: F2  # Choose a class with at least 256MB to run FastAPI and Uvicorn
entrypoint: uvicorn main:app --host 0.0.0.0 --port $PORT
automatic_scaling:
  target_cpu_utilization: 0.65
  min_instances: 1
  max_instances: 10

Step 3: Create a requirements.txt File⚑

Create a requirements.txt file in the root directory of your project and add the necessary dependencies:

fastapi==0.68.1
uvicorn[standard]==0.15.0

Step 4: Deploy Your Application⚑

Before you deploy, make sure you're authenticated to Google Cloud:

gcloud auth login

Next, set your project ID:

gcloud config set project your-project-id

Finally, deploy your app:

gcloud app deploy

Your FastAPI application should now be deployed to Google App Engine!

Bonus: Deploy with github actions⚑

To deploy your FastAPI application on Google App Engine using GitHub Actions, you'll first need to create a service account in your Google Cloud Project. This service account should have the 'App Engine Deployer' and 'Storage Admin' roles to allow it to deploy applications and upload to the Cloud Storage bucket. Download the JSON key file for this service account and store it as a secret (let's say GCP_SA_KEY) in your GitHub repository.

Here's a simple GitHub Actions workflow that can be used for deployment. Create a new file under .github/workflows in your repository named deploy.yml and add the following content:

name: Deploy to Google App Engine

on:
  push:
    branches:
      - main  # Trigger the workflow on push to main branch

jobs:
  deploy:
    runs-on: ubuntu-latest

    steps:
    - name: Checkout code
      uses: actions/checkout@v2

    - name: Set up Python 3.9
      uses: actions/setup-python@v2
      with:
        python-version: 3.9

    - name: Install dependencies
      run: |
        python -m pip install --upgrade pip
        pip install -r requirements.txt

    - name: Setup gcloud CLI
      uses: google-github-actions/setup-gcloud@master
      with:
        service_account_key: ${{ secrets.GCP_SA_KEY }}
        project_id: your-gcp-project-id
        export_default_credentials: true

    - name: Deploy to App Engine
      run: gcloud app deploy --quiet

Conclusion⚑

Google App Engine is a powerful platform for deploying Python web applications. With it, you can focus on building your FastAPI application and leave the infrastructure management to Google.

References⚑

• Fastapi
• Github Actions