FastAPI Integration for Oauth2 authentication

Easily integrate OAuth2 authentication into your FastAPI project using Omni-Authify library. This guide will walk you through configuration, setting up API views, updating URLs, and best practices.

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⚙️ Configure .env file

To use Omni-Authify in to your FastAPI project, You have to store provider-related credentials in an .env file to include Facebook, GitHub, Google and/or any other OAuth providers.

.env file

OMNI_AUTHIFY_ENABLED_PROVIDERS=facebook,linkedin

FACEBOOK_CLIENT_ID=your-facebook-client-id
FACEBOOK_CLIENT_SECRET=your-facebook-client-secret
FACEBOOK_REDIRECT_URI=https:/localhost:8000/facebook/callback
FACEBOOK_STATE='your_strong_state'
FACEBOOK_SCOPE='email,public_profile'
FACEBOOK_FIELDS='id,name,email,picture'

GITHUB_CLIENT_ID=your-github-client-id
GITHUB_CLIENT_SECRET=your-github-client-secret
GITHUB_REDIRECT_URI=https://localhost:8000/github/callback
GITHUB_SCOPE=user,repo

GOOGLE_CLIENT_ID=your-google-client-id
GOOGLE_CLIENT_SECRET=your-google-client-secret
GOOGLE_REDIRECT_URI=https://localhost:8000/google/callback
GOOGLE_STATE=your-strong-state
GOOGLE_SCOPES='openid profile email https://www.googleapis.com/auth/contacts.readonly' # Don't seperate the fields with commas

LINKEDIN_CLIENT_ID=your-linkedin-client-id
LINKEDIN_CLIENT_SECRET=your-linkedin-client-id
LINKEDIN_REDIRECT_URI=http://localhost:8000/linkedin/callback
LINKEDIN_SCOPE=openid,profile,w_member_social,email

Go and take a look at the Providers SetUP Guide to get Provider related credentials!

• Supported Providers and Frameworks

RestAPI Views

Learn how to create API views to handle Provider login and callback in your FastAPI application.

📝 Prerequisites

• Installation: Install Omni-Authify with FastAPI framework support using the following command:

  pip install omni-authify[fastapi]
• FastAPI version: 0.115.0 or higher

• FastAPI installed

• Omni-Authify installed and configured (see Installation Guide)

🚀 Setting Up API Views

Create API views to handle the login and callback processes.

# Omni-Authify Integration with FastAPI

from fastapi import FastAPI, Request, HTTPException
from fastapi.responses import RedirectResponse
from pydantic import BaseModel
from typing import Optional

from omni_authify.frameworks.fastapi import OmniAuthifyFastAPI

app = FastAPI()

# ======== Facebook Login ========
@app.get("/facebook/login")
def facebook_login():
    try:
        auth = OmniAuthifyFastAPI(provider_name="facebook")
        auth_url = auth.get_auth_url()
        return RedirectResponse(auth_url)
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Error initiating Facebook login: {str(e)}")

@app.get("/facebook/callback")
def facebook_callback(request: Request):
    code = request.query_params.get("code")
    if not code:
        raise HTTPException(status_code=400, detail="No code provided")

    try:
        auth = OmniAuthifyFastAPI(provider_name="facebook")
        user_info = auth.get_user_info(code)
        print(f"User Info: {user_info}")
        
        # TODO: Authenticate/login the user and save the user_info
        return {"message": "User authenticated successfully", "user_info": user_info}
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Error processing Facebook callback: {str(e)}")

# ======== GitHub Login ========
@app.get("/github/login")
def github_login():
    try:
        auth = OmniAuthifyFastAPI(provider_name="github")
        auth_url = auth.get_auth_url()
        return RedirectResponse(auth_url)
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Error initiating GitHub login: {str(e)}")

@app.get("/github/callback")
def github_callback(request: Request):
    code = request.query_params.get("code")
    if not code:
        raise HTTPException(status_code=400, detail="No code provided")

    try:
        auth = OmniAuthifyFastAPI(provider_name="github")
        user_info = auth.get_user_info(code)
        print(f"User Info: {user_info}")
        
        # TODO: Authenticate/login the user and save the user_info
        return {"message": "User authenticated successfully", "user_info": user_info}
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Error processing GitHub callback: {str(e)}")


# ======== Google Login ========
@app.get("/google/login")
def google_login():
    try:
        auth = OmniAuthifyFastAPI(provider_name="google")
        auth_url = auth.get_auth_url()
        return RedirectResponse(auth_url)
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Error initiating Google login: {str(e)}")

@app.get("/google/callback")
def google_callback(request: Request):
    code = request.query_params.get("code")
    if not code:
        raise HTTPException(status_code=400, detail="No code provided")

    try:
        auth = OmniAuthifyFastAPI(provider_name="google")
        user_info = auth.get_user_info(code)
        print(f"User Info: {user_info}")
        
        # TODO: Authenticate/login the user and save the user_info
        return {"message": "User authenticated successfully", "user_info": user_info}
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Error processing Google callback: {str(e)}")


# ======== LinkedIn Login ========
@app.get("/linkedin/login")
def linkedin_login():
    try:
        auth = OmniAuthifyFastAPI(provider_name="linkedin")
        auth_url = auth.get_auth_url()
        return RedirectResponse(auth_url)
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Error initiating LinkedIn login: {str(e)}")

@app.get("/google/callback")
def linkedin_callback(request: Request):
    code = request.query_params.get("code")
    if not code:
        raise HTTPException(status_code=400, detail="No code provided")

    try:
        auth = OmniAuthifyFastAPI(provider_name="linkedin")
        user_info = auth.get_user_info(code)
        print(f"User Info: {user_info}")
        
        # TODO: Authenticate/login the user and save the user_info
        return {"message": "User authenticated successfully", "user_info": user_info}
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Error processing LinkedIn callback: {str(e)}")

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✅ Best Practices

• 🔒 Use Environment Variables: Always use environment variables to store important information like client_id and client_secret. This helps keep your credentials safe 🛡️.

• 🔗 Match Redirect URI: Make sure the redirect_uri is consistent between your Provider App settings and your code to avoid errors 🚫.

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Omni-Authify makes adding Oauth2 authentication to your RESTAPI app straightforward and blazingly fast. Follow these steps and best practices to provide your users with a seamless login experience. 🚀✨