OAuth2 client library

Authenticate user with third-party OAuth2 provider for your Fastapi app

Description

The library automates recieving of user email from oauth2 provider. Two steps:

1. Redirect user to lib's endpoint and get token as a response.
2. Use the token to call lib's endpoint to get user's email

Example

1. Get token

Redirect user to backend lib's endpoint

Ex.:

    curl -X 'GET' \
    'http://127.0.0.1:8000/api/oauth/redirect?provider=google' \
    -H 'accept: application/json'

...and get token as response

Ex.:

    {
        "access_token": "TokenSomeStringValue"
    }

2. Get user email

Call userinfo endpoint

Ex.:

    curl --location 'http://127.0.0.1:8000/api/oauth/userinfo' \
    --header 'Authorization: Bearer TokenSomeStringValue'

...and get user's email as response

Ex.:

    {
        "email": "roadtoumba@gmail.com"
    }

How to integrate into your fastapi app

Backend

Import router

from oauth_client_lib import oauth_router

app = FastAPI()

app.include_router(oauth_router, prefix='/api')

Your fastapi app got new endpoints now:

Frontend

Add oauth2 providers' pics

Ex.:

Link providers' pics to router's endpoints

• for google: /api/oauth/authorize?provider=google
• for yandex: /api/oauth/authorize?provider=yandex

Settings

Environment

There must be variables in your environment (use .env file, for example):

• OAUTH_DB_URI - postgres db connection for oauth purposes (grants, tokens, etc..)
• API_HOST - you fastapi app host

Ex.:

OAUTH_DB_URI=postgresql://user:pwd123@localhost:5432/oauth
API_HOST=http://192.168.0.100

config.yaml

You can add custom oauth2 provider into oauth/providers:

oauth:
    providers:
        <provider_name>:
            scopes:
            - <scope1>
            - <scope2>
            - ...list of scopes enougth to request email
            urls:
                code: https://authorise-endpoint-that-returns-authorization-code
                token: https://token-request-endpoint
                userinfo: https://userinfo-endpoint

Use provider_name as a query param while redirecting user on step 1 of example