added Seznam SSO provider (#194)

* add seznam example

* add info to README.md

* add SeznamSSO to test_providers

* add SeznamSSO

* add client_secret comment

* Organize imports (ruff)

README.md

@@ -76,6 +76,7 @@ I tend to process Pull Requests faster when properly caffeinated 😉.
 - Line (by Jimmy Yeh) - [jimmyyyeh](https://github.com/jimmyyyeh)
 - LinkedIn (by Alessandro Pischedda) - [Cereal84](https://github.com/Cereal84)
 - Yandex (by Akim Faskhutdinov) – [akimrx](https://github.com/akimrx)
+- Seznam (by Tomas Koutek) - [TomasKoutek](https://github.com/TomasKoutek)
 
 See [Contributing](#contributing) for a guide on how to contribute your own login provider.
 

examples/seznam.py

@@ -0,0 +1,39 @@
+"""Seznam Login Example"""
+
+import os
+import uvicorn
+from fastapi import FastAPI
+from fastapi import Request
+
+from fastapi_sso.sso.seznam import SeznamSSO
+
+CLIENT_ID = os.environ["CLIENT_ID"]
+CLIENT_SECRET = os.environ["CLIENT_SECRET"]
+
+app = FastAPI()
+
+sso = SeznamSSO(
+    client_id=CLIENT_ID,
+    client_secret=CLIENT_SECRET,
+    redirect_uri="http://localhost:5000/auth/callback",
+    allow_insecure_http=True,
+)
+
+
+@app.get("/auth/login")
+async def auth_init():
+    """Initialize auth and redirect"""
+    with sso:
+        return await sso.get_login_redirect()
+
+
+@app.get("/auth/callback")
+async def auth_callback(request: Request):
+    """Verify login"""
+    with sso:
+        user = await sso.verify_and_process(request, params={"client_secret": CLIENT_SECRET})  # <- "client_secret" parameter is needed!
+    return user
+
+
+if __name__ == "__main__":
+    uvicorn.run(app="examples.seznam:app", host="127.0.0.1", port=5000)

fastapi_sso/sso/seznam.py

@@ -0,0 +1,39 @@
+"""Seznam SSO Login Helper."""
+
+from typing import TYPE_CHECKING, ClassVar, Optional
+
+from fastapi_sso.sso.base import DiscoveryDocument, OpenID, SSOBase
+
+if TYPE_CHECKING:
+    import httpx  # pragma: no cover
+
+
+# https://vyvojari.seznam.cz/oauth/doc
+
+
+class SeznamSSO(SSOBase):
+    """Class providing login via Seznam OAuth."""
+
+    provider = "seznam"
+    base_url = "https://login.szn.cz/api/v1"
+    scope: ClassVar = ["identity", "avatar"]  # + ["contact-phone", "adulthood", "birthday", "gender"]
+
+    async def get_discovery_document(self) -> DiscoveryDocument:
+        """Get document containing handy urls."""
+        return {
+            "authorization_endpoint": f"{self.base_url}/oauth/auth",
+            "token_endpoint": f"{self.base_url}/oauth/token",
+            "userinfo_endpoint": f"{self.base_url}/user",
+        }
+
+    async def openid_from_response(self, response: dict, session: Optional["httpx.AsyncClient"] = None) -> OpenID:
+        """Return OpenID from user information provided by Seznam."""
+        return OpenID(
+            email=response.get("email"),
+            first_name=response.get("firstname"),
+            last_name=response.get("lastname"),
+            display_name=response.get("accountDisplayName"),
+            provider=self.provider,
+            id=response.get("oauth_user_id"),
+            picture=response.get("avatar_url"),
+        )

tests/test_providers.py

@@ -24,6 +24,7 @@
 from fastapi_sso.sso.linkedin import LinkedInSSO
 from fastapi_sso.sso.twitter import TwitterSSO
 from fastapi_sso.sso.yandex import YandexSSO
+from fastapi_sso.sso.seznam import SeznamSSO
 
 GenericProvider = create_provider(
     name="generic",
@@ -51,6 +52,7 @@
     LinkedInSSO,
     TwitterSSO,
     YandexSSO,
+    SeznamSSO,
 )
 
 # Run all tests for each of the listed providers