Source code for swh.core.api.classes

# Copyright (C) 2020  The Software Heritage developers
# See the AUTHORS file at the top-level directory of this distribution
# License: GNU General Public License version 3, or any later version
# See top-level LICENSE file for more information

from dataclasses import dataclass, field
import itertools
from typing import Callable, Generic, Iterable, List, Optional, TypeVar

TResult = TypeVar("TResult")
TToken = TypeVar("TToken")


[docs]@dataclass(eq=True) class PagedResult(Generic[TResult, TToken]): """Represents a page of results; with a token to get the next page""" results: List[TResult] = field(default_factory=list) next_page_token: Optional[TToken] = field(default=None)
def _stream_results(f, *args, page_token, **kwargs): """Helper for stream_results() and stream_results_optional()""" while True: page_result = f(*args, page_token=page_token, **kwargs) yield from page_result.results page_token = page_result.next_page_token if page_token is None: break
[docs]def stream_results( f: Callable[..., PagedResult[TResult, TToken]], *args, **kwargs ) -> Iterable[TResult]: """Consume the paginated result and stream the page results """ if "page_token" in kwargs: raise TypeError('stream_results has no argument "page_token".') yield from _stream_results(f, *args, page_token=None, **kwargs)
[docs]def stream_results_optional( f: Callable[..., Optional[PagedResult[TResult, TToken]]], *args, **kwargs ) -> Optional[Iterable[TResult]]: """Like stream_results(), but for functions ``f`` that return an Optional. """ if "page_token" in kwargs: raise TypeError('stream_results_optional has no argument "page_token".') res = f(*args, page_token=None, **kwargs) if res is None: return None else: if res.next_page_token is None: return iter(res.results) else: return itertools.chain( res.results, _stream_results(f, *args, page_token=res.next_page_token, **kwargs), )