src/utils/google_drive_service.py

# src/utils/google_drive_service.py
from google.oauth2 import service_account
from googleapiclient.discovery import build
from googleapiclient.http import MediaIoBaseDownload
import io
import os

class GoogleDriveService:
    def __init__(self, credentials_path: str):
        """
        Initialize Google Drive service
        
        Args:
            credentials_path (str): Path to service account credentials file
        """
        self.credentials = service_account.Credentials.from_service_account_file(
            credentials_path,
            scopes=['https://www.googleapis.com/auth/drive.readonly']
        )
        self.service = build('drive', 'v3', credentials=self.credentials)

    def get_folder_contents(self, folder_id: str):
        """
        Get contents of a Drive folder
        
        Args:
            folder_id (str): ID of the folder to process
            
        Returns:
            List[Dict]: List of file metadata
        """
        query = f"'{folder_id}' in parents and trashed=false"
        results = self.service.files().list(
            q=query,
            fields="files(id, name, mimeType,modifiedTime)",
            supportsAllDrives=True,
            includeItemsFromAllDrives=True
        ).execute()
        return results.get('files', [])

    def download_file(self, file_id: str) -> bytes:
        """
        Download a file from Drive
        
        Args:
            file_id (str): ID of the file to download
            
        Returns:
            bytes: File content
        """
        request = self.service.files().get_media(fileId=file_id)
        content = io.BytesIO()
        downloader = MediaIoBaseDownload(content, request)
        
        done = False
        while not done:
            _, done = downloader.next_chunk()
            
        content.seek(0)
        return content.read()

    def export_file(self, file_id: str, mime_type: str) -> bytes:
        """
        Export a Google Workspace file to a different format
        
        Args:
            file_id (str): ID of the file to export
            mime_type (str): MIME type to export to
            
        Returns:
            bytes: Exported file content
        """
        request = self.service.files().export_media(
            fileId=file_id,
            mimeType=mime_type
        )
        content = io.BytesIO()
        downloader = MediaIoBaseDownload(content, request)
        
        done = False
        while not done:
            _, done = downloader.next_chunk()
            
        content.seek(0)
        return content.read()