PartFile.py 文件源码

def total_len(o):
    # Stolen from requests_toolbelt and modified
    if hasattr(o, '__len__'):
        return len(o)

    if hasattr(o, 'len'):
        return o.len

    if hasattr(o, 'fileno'):
        try:
            fileno = o.fileno()
        except io.UnsupportedOperation:
            pass
        else:
            return os.fstat(fileno).st_size

    if hasattr(o, 'getvalue'):
        # e.g. BytesIO, cStringIO.StringIO
        return len(o.getvalue())

    try:
        current_pos = o.tell()
        length = o.seek(0, 2)
        o.seek(current_pos, 0)
        return length
    except IOError:
        pass