]> jfr.im git - yt-dlp.git/blobdiff - yt_dlp/utils.py
[cleanup] Misc cleanup
[yt-dlp.git] / yt_dlp / utils.py
index 3b75ab6b3cff2df96046b3fa527c8555380c9e78..8a9567de44087ced99b9030dd570f4b467419716 100644 (file)
@@ -737,8 +737,8 @@ def extract_basic_auth(url):
         parts.hostname if parts.port is None
         else '%s:%d' % (parts.hostname, parts.port))))
     auth_payload = base64.b64encode(
-        ('%s:%s' % (parts.username, parts.password or '')).encode('utf-8'))
-    return url, 'Basic ' + auth_payload.decode('utf-8')
+        ('%s:%s' % (parts.username, parts.password or '')).encode())
+    return url, f'Basic {auth_payload.decode()}'
 
 
 def sanitized_Request(url, *args, **kwargs):
@@ -917,6 +917,8 @@ def make_HTTPS_handler(params, **kwargs):
     context.check_hostname = opts_check_certificate
     if params.get('legacyserverconnect'):
         context.options |= 4  # SSL_OP_LEGACY_SERVER_CONNECT
+        # Allow use of weaker ciphers in Python 3.10+. See https://bugs.python.org/issue43998
+        context.set_ciphers('DEFAULT')
     context.verify_mode = ssl.CERT_REQUIRED if opts_check_certificate else ssl.CERT_NONE
     if opts_check_certificate:
         if has_certifi and 'no-certifi' not in params.get('compat_opts', []):
@@ -930,12 +932,17 @@ def make_HTTPS_handler(params, **kwargs):
             except ssl.SSLError:
                 # enum_certificates is not present in mingw python. See https://github.com/yt-dlp/yt-dlp/issues/1151
                 if sys.platform == 'win32' and hasattr(ssl, 'enum_certificates'):
-                    # Create a new context to discard any certificates that were already loaded
-                    context = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
-                    context.check_hostname, context.verify_mode = True, ssl.CERT_REQUIRED
                     for storename in ('CA', 'ROOT'):
                         _ssl_load_windows_store_certs(context, storename)
                 context.set_default_verify_paths()
+    client_certfile = params.get('client_certificate')
+    if client_certfile:
+        try:
+            context.load_cert_chain(
+                client_certfile, keyfile=params.get('client_certificate_key'),
+                password=params.get('client_certificate_password'))
+        except ssl.SSLError:
+            raise YoutubeDLError('Unable to load client certificate')
     return YoutubeDLHTTPSHandler(params, context=context, **kwargs)
 
 
@@ -1332,7 +1339,7 @@ def http_response(self, req, resp):
             location = resp.headers.get('Location')
             if location:
                 # As of RFC 2616 default charset is iso-8859-1 that is respected by python 3
-                location = location.encode('iso-8859-1').decode('utf-8')
+                location = location.encode('iso-8859-1').decode()
                 location_escaped = escape_url(location)
                 if location != location_escaped:
                     del resp.headers['Location']
@@ -1406,9 +1413,14 @@ def https_open(self, req):
             conn_class = make_socks_conn_class(conn_class, socks_proxy)
             del req.headers['Ytdl-socks-proxy']
 
-        return self.do_open(functools.partial(
-            _create_http_connection, self, conn_class, True),
-            req, **kwargs)
+        try:
+            return self.do_open(
+                functools.partial(_create_http_connection, self, conn_class, True), req, **kwargs)
+        except urllib.error.URLError as e:
+            if (isinstance(e.reason, ssl.SSLError)
+                    and getattr(e.reason, 'reason', None) == 'SSLV3_ALERT_HANDSHAKE_FAILURE'):
+                raise YoutubeDLError('SSLV3_ALERT_HANDSHAKE_FAILURE: Try using --legacy-server-connect')
+            raise
 
 
 class YoutubeDLCookieJar(compat_cookiejar.MozillaCookieJar):
@@ -1427,57 +1439,71 @@ class YoutubeDLCookieJar(compat_cookiejar.MozillaCookieJar):
         'CookieFileEntry',
         ('domain_name', 'include_subdomains', 'path', 'https_only', 'expires_at', 'name', 'value'))
 
-    def save(self, filename=None, ignore_discard=False, ignore_expires=False):
+    def __init__(self, filename=None, *args, **kwargs):
+        super().__init__(None, *args, **kwargs)
+        if self.is_path(filename):
+            filename = os.fspath(filename)
+        self.filename = filename
+
+    @staticmethod
+    def _true_or_false(cndn):
+        return 'TRUE' if cndn else 'FALSE'
+
+    @staticmethod
+    def is_path(file):
+        return isinstance(file, (str, bytes, os.PathLike))
+
+    @contextlib.contextmanager
+    def open(self, file, *, write=False):
+        if self.is_path(file):
+            with open(file, 'w' if write else 'r', encoding='utf-8') as f:
+                yield f
+        else:
+            if write:
+                file.truncate(0)
+            yield file
+
+    def _really_save(self, f, ignore_discard=False, ignore_expires=False):
+        now = time.time()
+        for cookie in self:
+            if (not ignore_discard and cookie.discard
+                    or not ignore_expires and cookie.is_expired(now)):
+                continue
+            name, value = cookie.name, cookie.value
+            if value is None:
+                # cookies.txt regards 'Set-Cookie: foo' as a cookie
+                # with no name, whereas http.cookiejar regards it as a
+                # cookie with no value.
+                name, value = '', name
+            f.write('%s\n' % '\t'.join((
+                cookie.domain,
+                self._true_or_false(cookie.domain.startswith('.')),
+                cookie.path,
+                self._true_or_false(cookie.secure),
+                str_or_none(cookie.expires, default=''),
+                name, value
+            )))
+
+    def save(self, filename=None, *args, **kwargs):
         """
         Save cookies to a file.
+        Code is taken from CPython 3.6
+        https://github.com/python/cpython/blob/8d999cbf4adea053be6dbb612b9844635c4dfb8e/Lib/http/cookiejar.py#L2091-L2117 """
 
-        Most of the code is taken from CPython 3.8 and slightly adapted
-        to support cookie files with UTF-8 in both python 2 and 3.
-        """
         if filename is None:
             if self.filename is not None:
                 filename = self.filename
             else:
                 raise ValueError(compat_cookiejar.MISSING_FILENAME_TEXT)
 
-        # Store session cookies with `expires` set to 0 instead of an empty
-        # string
+        # Store session cookies with `expires` set to 0 instead of an empty string
         for cookie in self:
             if cookie.expires is None:
                 cookie.expires = 0
 
-        with open(filename, 'w', encoding='utf-8') as f:
+        with self.open(filename, write=True) as f:
             f.write(self._HEADER)
-            now = time.time()
-            for cookie in self:
-                if not ignore_discard and cookie.discard:
-                    continue
-                if not ignore_expires and cookie.is_expired(now):
-                    continue
-                if cookie.secure:
-                    secure = 'TRUE'
-                else:
-                    secure = 'FALSE'
-                if cookie.domain.startswith('.'):
-                    initial_dot = 'TRUE'
-                else:
-                    initial_dot = 'FALSE'
-                if cookie.expires is not None:
-                    expires = compat_str(cookie.expires)
-                else:
-                    expires = ''
-                if cookie.value is None:
-                    # cookies.txt regards 'Set-Cookie: foo' as a cookie
-                    # with no name, whereas http.cookiejar regards it as a
-                    # cookie with no value.
-                    name = ''
-                    value = cookie.name
-                else:
-                    name = cookie.name
-                    value = cookie.value
-                f.write(
-                    '\t'.join([cookie.domain, initial_dot, cookie.path,
-                               secure, expires, name, value]) + '\n')
+            self._really_save(f, *args, **kwargs)
 
     def load(self, filename=None, ignore_discard=False, ignore_expires=False):
         """Load cookies from a file."""
@@ -1502,7 +1528,7 @@ def prepare_line(line):
             return line
 
         cf = io.StringIO()
-        with open(filename, encoding='utf-8') as f:
+        with self.open(filename) as f:
             for line in f:
                 try:
                     cf.write(prepare_line(line))
@@ -1587,9 +1613,21 @@ def redirect_request(self, req, fp, code, msg, headers, newurl):
         CONTENT_HEADERS = ("content-length", "content-type")
         # NB: don't use dict comprehension for python 2.6 compatibility
         newheaders = {k: v for k, v in req.headers.items() if k.lower() not in CONTENT_HEADERS}
+
+        # A 303 must either use GET or HEAD for subsequent request
+        # https://datatracker.ietf.org/doc/html/rfc7231#section-6.4.4
+        if code == 303 and m != 'HEAD':
+            m = 'GET'
+        # 301 and 302 redirects are commonly turned into a GET from a POST
+        # for subsequent requests by browsers, so we'll do the same.
+        # https://datatracker.ietf.org/doc/html/rfc7231#section-6.4.2
+        # https://datatracker.ietf.org/doc/html/rfc7231#section-6.4.3
+        if code in (301, 302) and m == 'POST':
+            m = 'GET'
+
         return compat_urllib_request.Request(
             newurl, headers=newheaders, origin_req_host=req.origin_req_host,
-            unverifiable=True)
+            unverifiable=True, method=m)
 
 
 def extract_timezone(date_str):
@@ -1712,14 +1750,14 @@ def subtitles_filename(filename, sub_lang, sub_format, expected_real_ext=None):
 
 
 def datetime_from_str(date_str, precision='auto', format='%Y%m%d'):
-    """
-    Return a datetime object from a string in the format YYYYMMDD or
-    (now|today|yesterday|date)[+-][0-9](microsecond|second|minute|hour|day|week|month|year)(s)?
-
-    format: string date format used to return datetime object from
-    precision: round the time portion of a datetime object.
-                auto|microsecond|second|minute|hour|day.
-                auto: round to the unit provided in date_str (if applicable).
+    R"""
+    Return a datetime object from a string.
+    Supported format:
+        (now|today|yesterday|DATE)([+-]\d+(microsecond|second|minute|hour|day|week|month|year)s?)?
+
+    @param format       strftime format of DATE
+    @param precision    Round the datetime object: auto|microsecond|second|minute|hour|day
+                        auto: round to the unit provided in date_str (if applicable).
     """
     auto_precision = False
     if precision == 'auto':
@@ -1731,7 +1769,7 @@ def datetime_from_str(date_str, precision='auto', format='%Y%m%d'):
     if date_str == 'yesterday':
         return today - datetime.timedelta(days=1)
     match = re.match(
-        r'(?P<start>.+)(?P<sign>[+-])(?P<time>\d+)(?P<unit>microsecond|second|minute|hour|day|week|month|year)(s)?',
+        r'(?P<start>.+)(?P<sign>[+-])(?P<time>\d+)(?P<unit>microsecond|second|minute|hour|day|week|month|year)s?',
         date_str)
     if match is not None:
         start_time = datetime_from_str(match.group('start'), precision, format)
@@ -1754,16 +1792,14 @@ def datetime_from_str(date_str, precision='auto', format='%Y%m%d'):
 
 
 def date_from_str(date_str, format='%Y%m%d', strict=False):
-    """
-    Return a datetime object from a string in the format YYYYMMDD or
-    (now|today|yesterday|date)[+-][0-9](microsecond|second|minute|hour|day|week|month|year)(s)?
-
-    If "strict", only (now|today)[+-][0-9](day|week|month|year)(s)? is allowed
+    R"""
+    Return a date object from a string using datetime_from_str
 
-    format: string date format used to return datetime object from
+    @param strict  Restrict allowed patterns to "YYYYMMDD" and
+                   (now|today|yesterday)(-\d+(day|week|month|year)s?)?
     """
-    if strict and not re.fullmatch(r'\d{8}|(now|today)[+-]\d+(day|week|month|year)(s)?', date_str):
-        raise ValueError(f'Invalid date format {date_str}')
+    if strict and not re.fullmatch(r'\d{8}|(now|today|yesterday)(-\d+(day|week|month|year)s?)?', date_str):
+        raise ValueError(f'Invalid date format "{date_str}"')
     return datetime_from_str(date_str, precision='microsecond', format=format).date()
 
 
@@ -1857,9 +1893,8 @@ def write_string(s, out=None, encoding=None):
     assert isinstance(s, str)
     out = out or sys.stderr
 
-    from .compat import WINDOWS_VT_MODE  # Must be imported locally
-    if WINDOWS_VT_MODE:
-        s = s.replace('\n', ' \n')
+    if compat_os_name == 'nt' and supports_terminal_sequences(out):
+        s = re.sub(r'([\r\n]+)', r' \1', s)
 
     if 'b' in getattr(out, 'mode', ''):
         byt = s.encode(encoding or preferredencoding(), 'ignore')
@@ -2011,7 +2046,11 @@ def __enter__(self):
             self.f.close()
             raise
         if 'w' in self.mode:
-            self.f.truncate()
+            try:
+                self.f.truncate()
+            except OSError as e:
+                if e.errno != 29:  # Illegal seek, expected when self.f is a FIFO
+                    raise e
         return self
 
     def unlock(self):
@@ -2281,7 +2320,7 @@ def setproctitle(title):
         # a bytestring, but since unicode_literals turns
         # every string into a unicode string, it fails.
         return
-    title_bytes = title.encode('utf-8')
+    title_bytes = title.encode()
     buf = ctypes.create_string_buffer(len(title_bytes))
     buf.value = title_bytes
     try:
@@ -2323,13 +2362,13 @@ def base_url(url):
 
 def urljoin(base, path):
     if isinstance(path, bytes):
-        path = path.decode('utf-8')
+        path = path.decode()
     if not isinstance(path, compat_str) or not path:
         return None
     if re.match(r'^(?:[a-zA-Z][a-zA-Z0-9+-.]*:)?//', path):
         return path
     if isinstance(base, bytes):
-        base = base.decode('utf-8')
+        base = base.decode()
     if not isinstance(base, compat_str) or not re.match(
             r'^(?:https?:)?//', base):
         return None
@@ -2529,49 +2568,48 @@ def get_exe_version(exe, args=['--version'],
 
 
 class LazyList(collections.abc.Sequence):
-    ''' Lazy immutable list from an iterable
-    Note that slices of a LazyList are lists and not LazyList'''
+    """Lazy immutable list from an iterable
+    Note that slices of a LazyList are lists and not LazyList"""
 
     class IndexError(IndexError):
         pass
 
     def __init__(self, iterable, *, reverse=False, _cache=None):
-        self.__iterable = iter(iterable)
-        self.__cache = [] if _cache is None else _cache
-        self.__reversed = reverse
+        self._iterable = iter(iterable)
+        self._cache = [] if _cache is None else _cache
+        self._reversed = reverse
 
     def __iter__(self):
-        if self.__reversed:
+        if self._reversed:
             # We need to consume the entire iterable to iterate in reverse
             yield from self.exhaust()
             return
-        yield from self.__cache
-        for item in self.__iterable:
-            self.__cache.append(item)
+        yield from self._cache
+        for item in self._iterable:
+            self._cache.append(item)
             yield item
 
-    def __exhaust(self):
-        self.__cache.extend(self.__iterable)
-        # Discard the emptied iterable to make it pickle-able
-        self.__iterable = []
-        return self.__cache
+    def _exhaust(self):
+        self._cache.extend(self._iterable)
+        self._iterable = []  # Discard the emptied iterable to make it pickle-able
+        return self._cache
 
     def exhaust(self):
-        ''' Evaluate the entire iterable '''
-        return self.__exhaust()[::-1 if self.__reversed else 1]
+        """Evaluate the entire iterable"""
+        return self._exhaust()[::-1 if self._reversed else 1]
 
     @staticmethod
-    def __reverse_index(x):
+    def _reverse_index(x):
         return None if x is None else -(x + 1)
 
     def __getitem__(self, idx):
         if isinstance(idx, slice):
-            if self.__reversed:
-                idx = slice(self.__reverse_index(idx.start), self.__reverse_index(idx.stop), -(idx.step or 1))
+            if self._reversed:
+                idx = slice(self._reverse_index(idx.start), self._reverse_index(idx.stop), -(idx.step or 1))
             start, stop, step = idx.start, idx.stop, idx.step or 1
         elif isinstance(idx, int):
-            if self.__reversed:
-                idx = self.__reverse_index(idx)
+            if self._reversed:
+                idx = self._reverse_index(idx)
             start, stop, step = idx, idx, 0
         else:
             raise TypeError('indices must be integers or slices')
@@ -2580,35 +2618,35 @@ def __getitem__(self, idx):
                 or (stop is None and step > 0)):
             # We need to consume the entire iterable to be able to slice from the end
             # Obviously, never use this with infinite iterables
-            self.__exhaust()
+            self._exhaust()
             try:
-                return self.__cache[idx]
+                return self._cache[idx]
             except IndexError as e:
                 raise self.IndexError(e) from e
-        n = max(start or 0, stop or 0) - len(self.__cache) + 1
+        n = max(start or 0, stop or 0) - len(self._cache) + 1
         if n > 0:
-            self.__cache.extend(itertools.islice(self.__iterable, n))
+            self._cache.extend(itertools.islice(self._iterable, n))
         try:
-            return self.__cache[idx]
+            return self._cache[idx]
         except IndexError as e:
             raise self.IndexError(e) from e
 
     def __bool__(self):
         try:
-            self[-1] if self.__reversed else self[0]
+            self[-1] if self._reversed else self[0]
         except self.IndexError:
             return False
         return True
 
     def __len__(self):
-        self.__exhaust()
-        return len(self.__cache)
+        self._exhaust()
+        return len(self._cache)
 
     def __reversed__(self):
-        return type(self)(self.__iterable, reverse=not self.__reversed, _cache=self.__cache)
+        return type(self)(self._iterable, reverse=not self._reversed, _cache=self._cache)
 
     def __copy__(self):
-        return type(self)(self.__iterable, reverse=self.__reversed, _cache=self.__cache)
+        return type(self)(self._iterable, reverse=self._reversed, _cache=self._cache)
 
     def __repr__(self):
         # repr and str should mimic a list. So we exhaust the iterable
@@ -2822,9 +2860,9 @@ def _multipart_encode_impl(data, boundary):
     for k, v in data.items():
         out += b'--' + boundary.encode('ascii') + b'\r\n'
         if isinstance(k, compat_str):
-            k = k.encode('utf-8')
+            k = k.encode()
         if isinstance(v, compat_str):
-            v = v.encode('utf-8')
+            v = v.encode()
         # RFC 2047 requires non-ASCII field names to be encoded, while RFC 7578
         # suggests sending UTF-8 directly. Firefox sends UTF-8, too
         content = b'Content-Disposition: form-data; name="' + k + b'"\r\n\r\n' + v + b'\r\n'
@@ -3177,7 +3215,7 @@ def parse_codecs(codecs_str):
         return {}
     split_codecs = list(filter(None, map(
         str.strip, codecs_str.strip().strip(',').split(','))))
-    vcodec, acodec, tcodec, hdr = None, None, None, None
+    vcodec, acodec, scodec, hdr = None, None, None, None
     for full_codec in split_codecs:
         parts = full_codec.split('.')
         codec = parts[0].replace('0', '')
@@ -3195,16 +3233,16 @@ def parse_codecs(codecs_str):
             if not acodec:
                 acodec = full_codec
         elif codec in ('stpp', 'wvtt',):
-            if not tcodec:
-                tcodec = full_codec
+            if not scodec:
+                scodec = full_codec
         else:
             write_string(f'WARNING: Unknown codec {full_codec}\n')
-    if vcodec or acodec or tcodec:
+    if vcodec or acodec or scodec:
         return {
             'vcodec': vcodec or 'none',
             'acodec': acodec or 'none',
             'dynamic_range': hdr,
-            **({'tcodec': tcodec} if tcodec is not None else {}),
+            **({'scodec': scodec} if scodec is not None else {}),
         }
     elif len(split_codecs) == 2:
         return {
@@ -4673,87 +4711,56 @@ def _get_pixel(idx):
 
 
 def write_xattr(path, key, value):
-    # This mess below finds the best xattr tool for the job
-    try:
-        # try the pyxattr module...
-        import xattr
-
-        if hasattr(xattr, 'set'):  # pyxattr
-            # Unicode arguments are not supported in python-pyxattr until
-            # version 0.5.0
-            # See https://github.com/ytdl-org/youtube-dl/issues/5498
-            pyxattr_required_version = '0.5.0'
-            if version_tuple(xattr.__version__) < version_tuple(pyxattr_required_version):
-                # TODO: fallback to CLI tools
-                raise XAttrUnavailableError(
-                    'python-pyxattr is detected but is too old. '
-                    'yt-dlp requires %s or above while your version is %s. '
-                    'Falling back to other xattr implementations' % (
-                        pyxattr_required_version, xattr.__version__))
-
-            setxattr = xattr.set
-        else:  # xattr
-            setxattr = xattr.setxattr
+    # Windows: Write xattrs to NTFS Alternate Data Streams:
+    # http://en.wikipedia.org/wiki/NTFS#Alternate_data_streams_.28ADS.29
+    if compat_os_name == 'nt':
+        assert ':' not in key
+        assert os.path.exists(path)
 
         try:
-            setxattr(path, key, value)
+            with open(f'{path}:{key}', 'wb') as f:
+                f.write(value)
         except OSError as e:
             raise XAttrMetadataError(e.errno, e.strerror)
+        return
 
-    except ImportError:
-        if compat_os_name == 'nt':
-            # Write xattrs to NTFS Alternate Data Streams:
-            # http://en.wikipedia.org/wiki/NTFS#Alternate_data_streams_.28ADS.29
-            assert ':' not in key
-            assert os.path.exists(path)
-
-            ads_fn = path + ':' + key
-            try:
-                with open(ads_fn, 'wb') as f:
-                    f.write(value)
-            except OSError as e:
-                raise XAttrMetadataError(e.errno, e.strerror)
-        else:
-            user_has_setfattr = check_executable('setfattr', ['--version'])
-            user_has_xattr = check_executable('xattr', ['-h'])
-
-            if user_has_setfattr or user_has_xattr:
+    # UNIX Method 1. Use xattrs/pyxattrs modules
+    from .dependencies import xattr
 
-                value = value.decode('utf-8')
-                if user_has_setfattr:
-                    executable = 'setfattr'
-                    opts = ['-n', key, '-v', value]
-                elif user_has_xattr:
-                    executable = 'xattr'
-                    opts = ['-w', key, value]
+    setxattr = None
+    if getattr(xattr, '_yt_dlp__identifier', None) == 'pyxattr':
+        # Unicode arguments are not supported in pyxattr until version 0.5.0
+        # See https://github.com/ytdl-org/youtube-dl/issues/5498
+        if version_tuple(xattr.__version__) >= (0, 5, 0):
+            setxattr = xattr.set
+    elif xattr:
+        setxattr = xattr.setxattr
 
-                cmd = ([encodeFilename(executable, True)]
-                       + [encodeArgument(o) for o in opts]
-                       + [encodeFilename(path, True)])
+    if setxattr:
+        try:
+            setxattr(path, key, value)
+        except OSError as e:
+            raise XAttrMetadataError(e.errno, e.strerror)
+        return
 
-                try:
-                    p = Popen(
-                        cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE, stdin=subprocess.PIPE)
-                except OSError as e:
-                    raise XAttrMetadataError(e.errno, e.strerror)
-                stdout, stderr = p.communicate_or_kill()
-                stderr = stderr.decode('utf-8', 'replace')
-                if p.returncode != 0:
-                    raise XAttrMetadataError(p.returncode, stderr)
+    # UNIX Method 2. Use setfattr/xattr executables
+    exe = ('setfattr' if check_executable('setfattr', ['--version'])
+           else 'xattr' if check_executable('xattr', ['-h']) else None)
+    if not exe:
+        raise XAttrUnavailableError(
+            'Couldn\'t find a tool to set the xattrs. Install either the python "xattr" or "pyxattr" modules or the '
+            + ('"xattr" binary' if sys.platform != 'linux' else 'GNU "attr" package (which contains the "setfattr" tool)'))
 
-            else:
-                # On Unix, and can't find pyxattr, setfattr, or xattr.
-                if sys.platform.startswith('linux'):
-                    raise XAttrUnavailableError(
-                        "Couldn't find a tool to set the xattrs. "
-                        "Install either the python 'pyxattr' or 'xattr' "
-                        "modules, or the GNU 'attr' package "
-                        "(which contains the 'setfattr' tool).")
-                else:
-                    raise XAttrUnavailableError(
-                        "Couldn't find a tool to set the xattrs. "
-                        "Install either the python 'xattr' module, "
-                        "or the 'xattr' binary.")
+    value = value.decode()
+    try:
+        p = Popen(
+            [exe, '-w', key, value, path] if exe == 'xattr' else [exe, '-n', key, '-v', value, path],
+            stdout=subprocess.PIPE, stderr=subprocess.PIPE, stdin=subprocess.PIPE)
+    except OSError as e:
+        raise XAttrMetadataError(e.errno, e.strerror)
+    stderr = p.communicate_or_kill()[1].decode('utf-8', 'replace')
+    if p.returncode:
+        raise XAttrMetadataError(p.returncode, stderr)
 
 
 def random_birthday(year_field, month_field, day_field):
@@ -4823,7 +4830,7 @@ def iri_to_uri(iri):
             net_location += ':' + urllib.parse.quote(iri_parts.password, safe=r"!$%&'()*+,~")
         net_location += '@'
 
-    net_location += iri_parts.hostname.encode('idna').decode('utf-8')  # Punycode for Unicode hostnames.
+    net_location += iri_parts.hostname.encode('idna').decode()  # Punycode for Unicode hostnames.
     # The 'idna' encoding produces ASCII text.
     if iri_parts.port is not None and iri_parts.port != 80:
         net_location += ':' + str(iri_parts.port)
@@ -5066,9 +5073,9 @@ def jwt_encode_hs256(payload_data, key, headers={}):
     }
     if headers:
         header_data.update(headers)
-    header_b64 = base64.b64encode(json.dumps(header_data).encode('utf-8'))
-    payload_b64 = base64.b64encode(json.dumps(payload_data).encode('utf-8'))
-    h = hmac.new(key.encode('utf-8'), header_b64 + b'.' + payload_b64, hashlib.sha256)
+    header_b64 = base64.b64encode(json.dumps(header_data).encode())
+    payload_b64 = base64.b64encode(json.dumps(payload_data).encode())
+    h = hmac.new(key.encode(), header_b64 + b'.' + payload_b64, hashlib.sha256)
     signature_b64 = base64.b64encode(h.digest())
     token = header_b64 + b'.' + payload_b64 + b'.' + signature_b64
     return token
@@ -5308,6 +5315,7 @@ def merge_headers(*dicts):
 
 class classproperty:
     def __init__(self, f):
+        functools.update_wrapper(self, f)
         self.f = f
 
     def __get__(self, _, cls):