Function download_or_cache

tools/cache_zenodo_svg.py:7–46

Get bytes from the given url or local cache. Parameters ---------- url : str The url to download. sha : str The sha256 of the file. Returns ------- BytesIO The file loaded into memory.

(url, version)

def download_or_cache(url, version):
    """
    Get bytes from the given url or local cache.

    Parameters
    ----------
    url : str
        The url to download.
    sha : str
        The sha256 of the file.

    Returns
    -------
    BytesIO
        The file loaded into memory.
    """
    cache_dir = _get_xdg_cache_dir()

    if cache_dir is not None:  # Try to read from cache.
        try:
            data = (cache_dir / version).read_bytes()
        except OSError:
            pass
        else:
            return BytesIO(data)

    with urllib.request.urlopen(
        urllib.request.Request(url, headers={"User-Agent": ""})
    ) as req:
        data = req.read()

    if cache_dir is not None:  # Try to cache the downloaded file.
        try:
            cache_dir.mkdir(parents=True, exist_ok=True)
            with open(cache_dir / version, "xb") as fout:
                fout.write(data)
        except OSError:
            pass

    return BytesIO(data)


def _get_xdg_cache_dir():