Taiga MCP Bridge

Instructions

Implementation Reference

• src/server.py:989-996 (handler)

  The main handler function for the 'unassign_epic_from_user' tool, registered via the @mcp.tool decorator. It authenticates the session, logs the action, and delegates to the update_epic helper by passing assigned_to=None to unassign the epic.

  @mcp.tool("unassign_epic_from_user", description="Unassigns a specific epic (sets assigned user to null).")
  def unassign_epic_from_user(session_id: str, epic_id: int) -> Dict[str, Any]:
      """Unassigns an epic."""
      logger.info(
          f"Executing unassign_epic_from_user: Epic {epic_id}, session {session_id[:8]}...")
      # Delegate to update_epic
      return update_epic(session_id, epic_id, assigned_to=None)

• src/server.py:923-957 (helper)

  Supporting helper function 'update_epic' that performs the core logic of updating an epic via the Taiga API (api.epics.edit), including version handling and error management. Called by unassign_epic_from_user with assigned_to=None.

  @mcp.tool("update_epic", description="Updates details of an existing epic.")
  def update_epic(session_id: str, epic_id: int, **kwargs) -> Dict[str, Any]:
      """Updates an epic. Pass fields to update as keyword arguments (e.g., subject, description, status_id, assigned_to, color)."""
      logger.info(
          f"Executing update_epic ID {epic_id} for session {session_id[:8]} with data: {kwargs}")
      taiga_client_wrapper = _get_authenticated_client(session_id) # Use wrapper variable name
      try:
          # Use pytaigaclient edit pattern for partial updates
          if not kwargs:
               logger.info(f"No fields provided for update on epic {epic_id}")
               return taiga_client_wrapper.api.epics.get(epic_id)
  
          # Get current epic data to retrieve version
          current_epic = taiga_client_wrapper.api.epics.get(epic_id)
          version = current_epic.get('version')
          if not version:
              raise ValueError(f"Could not determine version for epic {epic_id}")
              
          # Use edit method for partial updates with keyword arguments
          updated_epic = taiga_client_wrapper.api.epics.edit(
              epic_id=epic_id,
              version=version,
              **kwargs
          )
          logger.info(f"Epic {epic_id} update request sent.")
          return updated_epic
      except TaigaException as e:
          logger.error(
              f"Taiga API error updating epic {epic_id}: {e}", exc_info=False)
          raise e
      except Exception as e:
          logger.error(
              f"Unexpected error updating epic {epic_id}: {e}", exc_info=True)
          raise RuntimeError(f"Server error updating epic: {e}")

• src/server.py:39-52 (helper)

  Helper function to retrieve and validate the authenticated TaigaClientWrapper from the session store, used by all authenticated tools including unassign_epic_from_user.

  def _get_authenticated_client(session_id: str) -> TaigaClientWrapper:
      """
      Retrieves the authenticated TaigaClientWrapper for a given session ID.
      Raises PermissionError if the session is invalid or not found.
      """
      client = active_sessions.get(session_id)
      # Also check if the client object itself exists and is authenticated
      if not client or not client.is_authenticated:
          logger.warning(f"Invalid or expired session ID provided: {session_id}")
          # Raise PermissionError - FastMCP will map this to an appropriate error response
          raise PermissionError(
              f"Invalid or expired session ID: '{session_id}'. Please login again.")
      logger.debug(f"Retrieved valid client for session ID: {session_id}")
      return client

• src/taiga_client.py:15-29 (helper)

  The TaigaClientWrapper class provides the API client instance (self.api.epics.edit is ultimately called) and authentication management used by the tools.

  class TaigaClientWrapper:
      """
      A wrapper around the pytaiga-client library to manage API instance
      and authentication state.
      """
  
      def __init__(self, host: str):
          if not host:
              raise ValueError("Taiga host URL cannot be empty.")
          # Store host, but initialize client later during login/token auth
          self.host = host
          # Use the new client type
          self.api: Optional[TaigaClient] = None
          logger.info(f"TaigaClientWrapper initialized for host: {self.host}")