DM20 Protocol

Instructions

Implementation Reference

• src/dm20_protocol/storage.py:574-631 (handler)

  The `delete_campaign` method within `DnDStorage` class handles the deletion of campaigns by detecting the storage format (monolithic vs split) and removing the corresponding file or directory, and resetting the active campaign state if necessary.

  def delete_campaign(self, name: str) -> str:
      """Delete a campaign from storage.
  
      Supports both monolithic (single JSON file) and split (directory) formats.
      If the deleted campaign is the currently active one, all state is cleared.
  
      Args:
          name: The name of the campaign to delete
  
      Returns:
          The name of the deleted campaign
  
      Raises:
          FileNotFoundError: If the campaign does not exist
      """
      storage_format = self._detect_campaign_format(name)
  
      if storage_format == StorageFormat.NOT_FOUND:
          raise FileNotFoundError(f"Campaign '{name}' not found")
  
      safe_name = "".join(c for c in name if c.isalnum() or c in (' ', '-', '_', "'")).rstrip()
  
      if storage_format == StorageFormat.MONOLITHIC:
          file_path = self._get_campaign_file(name)
          file_path.unlink()
          logger.info(f"🗑️ Deleted monolithic campaign file: {file_path}")
      elif storage_format == StorageFormat.SPLIT:
          dir_path = self.data_dir / "campaigns" / safe_name
          # Safety check: path must be under campaigns directory
          campaigns_dir = (self.data_dir / "campaigns").resolve()
          if not dir_path.resolve().is_relative_to(campaigns_dir):
              raise ValueError(f"Unsafe path detected: {dir_path}")
          try:
              shutil.rmtree(dir_path)
          except OSError:
              # Retry: macOS race condition with file watchers / .DS_Store
              import time
              time.sleep(0.3)
              shutil.rmtree(dir_path)
          logger.info(f"🗑️ Deleted split campaign directory: {dir_path}")
  
      # If deleting the active campaign, clear all state
      if self._current_campaign and self._current_campaign.name == name:
          self._current_campaign = None
          self._current_format = StorageFormat.NOT_FOUND
          self._character_id_index.clear()
          self._player_name_index.clear()
          self._campaign_hash = ""
          self._rulebook_manager = None
          self._rules_version = "2024"
          self._interaction_mode = "classic"
          self._library_bindings = None
          self._discovery_tracker = None
          if hasattr(self, '_split_backend'):
              self._split_backend._current_campaign = None
          logger.info(f"🧹 Cleared active campaign state (was: '{name}')")
  
      return name