kanban-app/backend/app/services/storage/base.py

"""Abstract base class for storage adapters"""

from abc import ABC, abstractmethod
from io import BytesIO


class StorageAdapter(ABC):
    """Abstract base class for storage adapters"""

    @abstractmethod
    def upload_file(
        self,
        file_data: BytesIO,
        bucket_name: str,
        object_name: str,
        content_type: str,
    ) -> dict:
        """
        Upload a file to storage

        Args:
            file_data: File data as BytesIO
            bucket_name: Name of the bucket
            object_name: Name of the object in storage
            content_type: MIME type of the file

        Returns:
            dict: Upload result with metadata
        """
        pass

    @abstractmethod
    def download_file(self, bucket_name: str, object_name: str) -> BytesIO:
        """
        Download a file from storage

        Args:
            bucket_name: Name of the bucket
            object_name: Name of the object in storage

        Returns:
            BytesIO: File data
        """
        pass

    @abstractmethod
    def delete_file(self, bucket_name: str, object_name: str) -> bool:
        """
        Delete a file from storage

        Args:
            bucket_name: Name of the bucket
            object_name: Name of the object in storage

        Returns:
            bool: True if successful
        """
        pass

    @abstractmethod
    def generate_presigned_url(
        self, bucket_name: str, object_name: str, expires_in: int = 3600
    ) -> str:
        """
        Generate a presigned URL for file access

        Args:
            bucket_name: Name of the bucket
            object_name: Name of the object in storage
            expires_in: URL expiration time in seconds

        Returns:
            str: Presigned URL
        """
        pass

    @abstractmethod
    def file_exists(self, bucket_name: str, object_name: str) -> bool:
        """
        Check if a file exists in storage

        Args:
            bucket_name: Name of the bucket
            object_name: Name of the object in storage

        Returns:
            bool: True if file exists
        """
        pass

    @abstractmethod
    def get_file_info(self, bucket_name: str, object_name: str) -> dict:
        """
        Get file metadata

        Args:
            bucket_name: Name of the bucket
            object_name: Name of the object in storage

        Returns:
            dict: File metadata
        """
        pass

    @abstractmethod
    def ensure_bucket_exists(self, bucket_name: str) -> None:
        """
        Ensure a bucket exists, create if it doesn't

        Args:
            bucket_name: Name of the bucket
        """
        pass