List files and folders from a shared link in Dropbox

dropbox-shared-link-contents.py

import json
import logging
import os
from argparse import ArgumentParser
from logging import INFO
from pathlib import Path
from typing import Any, Dict, List, Optional

from dropbox import Dropbox
from dropbox.files import FileMetadata, FolderMetadata, Metadata, SharedLink


def main():
    logging.basicConfig(format='[%(levelname)s] %(message)s', level=INFO)
    logger = logging.getLogger()

    parser = ArgumentParser(
        description='List files and folders from a shared link in Dropbox.',
        epilog='Requires `$DROPBOX_ACCESS_TOKEN` with `files.metadata.read`'
               'permission and `sharing.read` permission. And it outputs '
               'contents from a given shared link as a JSON. A `null` value '
               'means it is a file.',
    )
    parser.add_argument('url', help='shared link URL')
    parser.add_argument('-o', '--output', type=Path,
                        help='write output to FILE instead of stdout',
                        metavar='FILE')
    args = parser.parse_args()
    url: str = args.url
    output: Optional[Path] = args.output

    dbx = Dropbox(get_access_token())

    tree: Dict[str, Any] = {}
    stack = []

    for entry in list_folder(dbx, url, ''):
        if not isinstance(entry, FolderMetadata):
            raise RuntimeError(type(entry))
        tree[entry.name] = {}
        stack.append([entry.name])

    while stack:
        path = stack.pop()

        logger.info(f'Requesting /{"/".join(path)}')

        cur = tree
        for segment in path:
            cur = cur[segment]

        for entry in list_folder(dbx, url, f'/{"/".join(path)}'):
            if isinstance(entry, FileMetadata):
                cur[entry.name] = None
            elif isinstance(entry, FolderMetadata):
                cur[entry.name] = {}
                stack.append([*path, entry.name])
            else:
                raise RuntimeError(type(entry))

    content = json.dumps(tree)

    if output is None:
        print(content, end='')
    else:
        with open(output, 'w') as file:
            file.write(content)


def get_access_token() -> str:
    if 'DROPBOX_ACCESS_TOKEN' not in os.environ:
        raise RuntimeError('missing `$DROPBOX_ACCESS_TOKEN`')
    return os.environ['DROPBOX_ACCESS_TOKEN']


def list_folder(dbx: Dropbox, url: str, path: str) -> List[Metadata]:
    result = dbx.files_list_folder(path, shared_link=SharedLink(url=url))
    ret = result.entries
    while result.has_more:
        result = dbx.files_list_folder_continue(result.cursor)
        ret.extend(result.entries)
    return ret


if __name__ == '__main__':
    main()