[Refactor]: Changes to Github Authentication (#5371)

Co-authored-by: openhands <openhands@all-hands.dev>
Co-authored-by: sp.wack <83104063+amanape@users.noreply.github.com>
Co-authored-by: Engel Nyst <enyst@users.noreply.github.com>

openhands/server/types.py

@@ -0,0 +1,42 @@
+from abc import ABC, abstractmethod
+from enum import Enum
+from typing import ClassVar, Protocol
+
+
+class AppMode(Enum):
+    OSS = 'oss'
+    SAAS = 'saas'
+
+
+class SessionMiddlewareInterface(Protocol):
+    """Protocol for session middleware classes."""
+
+    pass
+
+
+class OpenhandsConfigInterface(ABC):
+    CONFIG_PATH: ClassVar[str | None]
+    APP_MODE: ClassVar[AppMode]
+    POSTHOG_CLIENT_KEY: ClassVar[str]
+    GITHUB_CLIENT_ID: ClassVar[str]
+    ATTACH_SESSION_MIDDLEWARE_PATH: ClassVar[str]
+
+    @abstractmethod
+    def verify_config(self) -> None:
+        """Verify configuration settings."""
+        raise NotImplementedError
+
+    @abstractmethod
+    async def verify_github_repo_list(self, installation_id: int | None) -> None:
+        """Verify that repo list is being called via user's profile or Github App installations."""
+        raise NotImplementedError
+
+    @abstractmethod
+    async def get_config(self) -> dict[str, str]:
+        """Configure attributes for frontend"""
+        raise NotImplementedError
+
+    @abstractmethod
+    async def github_auth(self, data: dict) -> None:
+        """Handle GitHub authentication."""
+        raise NotImplementedError