feat: add session sharing support

Author: Simpleyyt

backend/app/application/errors/exceptions.py

@@ -32,5 +32,5 @@ def __init__(self, msg: str = "Internal server error"):
 
 
 class UnauthorizedError(AppException):
-    def __init__(self, msg: str = "Unauthorized"):
+    def __init__(self, msg: str = "Authentication required"):
         super().__init__(code=401, msg=msg, status_code=401) 

backend/app/application/services/agent_service.py

@@ -99,10 +99,13 @@ async def chat(
             yield event
         logger.info(f"Chat with session {session_id} completed")
 
-    async def get_session(self, session_id: str, user_id: str) -> Optional[Session]:
+    async def get_session(self, session_id: str, user_id: Optional[str] = None) -> Optional[Session]:
         """Get a session by ID, ensuring it belongs to the user"""
         logger.info(f"Getting session {session_id} for user {user_id}")
-        session = await self._session_repository.find_by_id_and_user_id(session_id, user_id)
+        if not user_id:
+            session = await self._session_repository.find_by_id(session_id)
+        else:
+            session = await self._session_repository.find_by_id_and_user_id(session_id, user_id)
         if not session:
             logger.error(f"Session {session_id} not found for user {user_id}")
         return session
@@ -209,12 +212,60 @@ async def file_view(self, session_id: str, file_path: str, user_id: str) -> File
             return FileViewResponse(**result.data)
         else:
             raise RuntimeError(f"Failed to read file: {result.message}")
+    
+    async def is_session_shared(self, session_id: str) -> bool:
+        """Check if a session is shared"""
+        logger.info(f"Checking if session {session_id} is shared")
+        session = await self._session_repository.find_by_id(session_id)
+        if not session:
+            logger.error(f"Session {session_id} not found")
+            raise RuntimeError("Session not found")
+        return session.is_shared
 
-    async def get_session_files(self, session_id: str, user_id: str) -> List[FileInfo]:
+    async def get_session_files(self, session_id: str, user_id: Optional[str] = None) -> List[FileInfo]:
         """Get files for a session, ensuring it belongs to the user"""
         logger.info(f"Getting files for session {session_id} for user {user_id}")
+        session = await self.get_session(session_id, user_id)
+        return session.files
+    
+    async def get_shared_session_files(self, session_id: str) -> List[FileInfo]:
+        """Get files for a shared session"""
+        logger.info(f"Getting files for shared session {session_id}")
+        session = await self._session_repository.find_by_id(session_id)
+        if not session or not session.is_shared:
+            logger.error(f"Shared session {session_id} not found or not shared")
+            raise RuntimeError("Session not found")
+        return session.files
+
+    async def share_session(self, session_id: str, user_id: str) -> None:
+        """Share a session, ensuring it belongs to the user"""
+        logger.info(f"Sharing session {session_id} for user {user_id}")
+        # First verify the session belongs to the user
         session = await self._session_repository.find_by_id_and_user_id(session_id, user_id)
         if not session:
             logger.error(f"Session {session_id} not found for user {user_id}")
             raise RuntimeError("Session not found")
-        return session.files
+        
+        await self._session_repository.update_shared_status(session_id, True)
+        logger.info(f"Session {session_id} shared successfully")
+
+    async def unshare_session(self, session_id: str, user_id: str) -> None:
+        """Unshare a session, ensuring it belongs to the user"""
+        logger.info(f"Unsharing session {session_id} for user {user_id}")
+        # First verify the session belongs to the user
+        session = await self._session_repository.find_by_id_and_user_id(session_id, user_id)
+        if not session:
+            logger.error(f"Session {session_id} not found for user {user_id}")
+            raise RuntimeError("Session not found")
+        
+        await self._session_repository.update_shared_status(session_id, False)
+        logger.info(f"Session {session_id} unshared successfully")
+
+    async def get_shared_session(self, session_id: str) -> Optional[Session]:
+        """Get a shared session by ID (no user authentication required)"""
+        logger.info(f"Getting shared session {session_id}")
+        session = await self._session_repository.find_by_id(session_id)
+        if not session or not session.is_shared:
+            logger.error(f"Shared session {session_id} not found or not shared")
+            return None
+        return session

backend/app/application/services/file_service.py

@@ -2,13 +2,15 @@
 import logging
 from app.domain.external.file import FileStorage
 from app.domain.models.file import FileInfo
+from app.application.services.token_service import TokenService
 
 # Set up logger
 logger = logging.getLogger(__name__)
 
 class FileService:
-    def __init__(self, file_storage: Optional[FileStorage] = None):
+    def __init__(self, file_storage: Optional[FileStorage] = None, token_service: Optional[TokenService] = None):
         self._file_storage = file_storage
+        self._token_service = token_service
 
     async def upload_file(self, file_data: BinaryIO, filename: str, user_id: str, content_type: Optional[str] = None, metadata: Optional[Dict[str, Any]] = None) -> FileInfo:
         """Upload file"""
@@ -58,7 +60,7 @@ async def delete_file(self, file_id: str, user_id: str) -> bool:
             logger.error(f"Failed to delete file {file_id} for user {user_id}: {str(e)}")
             raise
 
-    async def get_file_info(self, file_id: str, user_id: str) -> Optional[FileInfo]:
+    async def get_file_info(self, file_id: str, user_id: Optional[str] = None) -> Optional[FileInfo]:
         """Get file information"""
         logger.info(f"Get file info request: file_id={file_id}, user_id={user_id}")
         if not self._file_storage:
@@ -75,3 +77,44 @@ async def get_file_info(self, file_id: str, user_id: str) -> Optional[FileInfo]:
         except Exception as e:
             logger.error(f"Failed to get file info {file_id} for user {user_id}: {str(e)}")
             raise
+    
+    async def enrich_with_file_url(self, file_info: FileInfo) -> FileInfo:
+        """Enrich file information with file URL"""
+        logger.info(f"Enrich file info request: file_info={file_info}")
+        
+        try:
+            signed_url = await self.create_signed_url(file_info.file_id, file_info.user_id)
+            file_info.file_url = signed_url
+            return file_info
+        except Exception as e:
+            logger.error(f"Failed to enrich file info {file_info.file_id} with file URL: {str(e)}")
+            raise
+
+    async def create_signed_url(self, file_id: str, user_id: Optional[str] = None, expire_minutes: int = 30) -> str:
+        """Create signed URL for file download"""
+        logger.info(f"Create signed URL request: file_id={file_id}, user_id={user_id}, expire_minutes={expire_minutes}")
+        
+        if not self._token_service:
+            logger.error("Token service not available")
+            raise RuntimeError("Token service not available")
+        
+        # Validate expiration time (max 15 minutes)
+        if expire_minutes > 30:
+            expire_minutes = 30
+        
+        # Check if file exists and user has access
+        file_info = await self.get_file_info(file_id, user_id)
+        if not file_info:
+            logger.warning(f"File not found or access denied for signed URL: file_id={file_id}, user_id={user_id}")
+            raise FileNotFoundError("File not found")
+        
+        # Create signed URL for file download
+        base_url = f"/api/v1/files/{file_id}"
+        signed_url = self._token_service.create_signed_url(
+            base_url=base_url,
+            expire_minutes=expire_minutes
+        )
+        
+        logger.info(f"Created signed URL for file download for user {user_id}, file {file_id}")
+        
+        return signed_url

backend/app/domain/external/file.py

@@ -63,7 +63,7 @@ async def delete_file(
     async def get_file_info(
         self,
         file_id: str,
-        user_id: str
+        user_id: Optional[str] = None
     ) -> Optional[FileInfo]:
         """Get file metadata from storage
         

backend/app/domain/models/file.py

@@ -12,3 +12,4 @@ class FileInfo(BaseModel):
     upload_date: Optional[datetime] = None
     metadata: Optional[Dict[str, Any]] = None
     user_id: Optional[str] = None
+    file_url: Optional[str] = None

backend/app/domain/models/session.py

@@ -32,6 +32,7 @@ class Session(BaseModel):
     events: List[AgentEvent] = []
     files: List[FileInfo] = []
     status: SessionStatus = SessionStatus.PENDING
+    is_shared: bool = False  # Whether this session is shared publicly
 
     def get_last_plan(self) -> Optional[Plan]:
         """Get the last plan from the events"""

backend/app/domain/repositories/session_repository.py

@@ -63,6 +63,10 @@ async def decrement_unread_message_count(self, session_id: str) -> None:
         """Decrement the unread message count of a session"""
         ...
 
+    async def update_shared_status(self, session_id: str, is_shared: bool) -> None:
+        """Update the shared status of a session"""
+        ...
+    
     async def delete(self, session_id: str) -> None:
         """Delete a session"""
         ...

backend/app/infrastructure/external/file/gridfsfile.py

@@ -177,7 +177,7 @@ async def delete_file(self, file_id: str, user_id: str) -> bool:
             logger.error(f"Failed to delete file {file_id} for user {user_id}: {str(e)}")
             return False
 
-    async def get_file_info(self, file_id: str, user_id: str) -> Optional[FileInfo]:
+    async def get_file_info(self, file_id: str, user_id: Optional[str] = None) -> Optional[FileInfo]:
         """Get file information"""
         try:
             files_collection = self._get_files_collection()
@@ -195,7 +195,7 @@ async def get_file_info(self, file_id: str, user_id: str) -> Optional[FileInfo]:
 
             # Check if file belongs to the user
             file_user_id = file_info.get('metadata', {}).get('user_id')
-            if file_user_id != user_id:
+            if user_id is not None and file_user_id != user_id:
                 logger.warning(f"Access denied: file {file_id} does not belong to user {user_id}")
                 return None
 

backend/app/infrastructure/models/documents.py

@@ -96,6 +96,7 @@ class SessionDocument(BaseDocument[Session], id_field="session_id", domain_model
     events: List[AgentEvent]
     status: SessionStatus
     files: List[FileInfo] = []
+    is_shared: Optional[bool] = False
     class Settings:
         name = "sessions"
         indexes = [

backend/app/infrastructure/repositories/mongo_session_repository.py

@@ -167,3 +167,13 @@ async def decrement_unread_message_count(self, session_id: str) -> None:
         if not result:
             raise ValueError(f"Session {session_id} not found")
 
+    async def update_shared_status(self, session_id: str, is_shared: bool) -> None:
+        """Update the shared status of a session"""
+        result = await SessionDocument.find_one(
+            SessionDocument.session_id == session_id
+        ).update(
+            {"$set": {"is_shared": is_shared, "updated_at": datetime.now(UTC)}}
+        )
+        if not result:
+            raise ValueError(f"Session {session_id} not found")
+