util

@six.add_metaclass(_RetryMeta)
class Retry(object):
    """Retry configuration.

    Each retry attempt will create a new Retry object with updated values, so
    they can be safely reused.

    Retries can be defined as a default for a pool::

        retries = Retry(connect=5, read=2, redirect=5)
        http = PoolManager(retries=retries)
        response = http.request('GET', 'http://example.com/')

    Or per-request (which overrides the default for the pool)::

        response = http.request('GET', 'http://example.com/', retries=Retry(10))

    Retries can be disabled by passing ``False``::

        response = http.request('GET', 'http://example.com/', retries=False)

    Errors will be wrapped in :class:`~urllib3.exceptions.MaxRetryError` unless
    retries are disabled, in which case the causing exception will be raised.

    :param int total:
        Total number of retries to allow. Takes precedence over other counts.

        Set to ``None`` to remove this constraint and fall back on other
        counts.

        Set to ``0`` to fail on the first retry.

        Set to ``False`` to disable and imply ``raise_on_redirect=False``.

    :param int connect:
        How many connection-related errors to retry on.

        These are errors raised before the request is sent to the remote server,
        which we assume has not triggered the server to process the request.

        Set to ``0`` to fail on the first retry of this type.

    :param int read:
        How many times to retry on read errors.

        These errors are raised after the request was sent to the server, so the
        request may have side-effects.

        Set to ``0`` to fail on the first retry of this type.

    :param int redirect:
        How many redirects to perform. Limit this to avoid infinite redirect
        loops.

        A redirect is a HTTP response with a status code 301, 302, 303, 307 or
        308.

        Set to ``0`` to fail on the first retry of this type.

        Set to ``False`` to disable and imply ``raise_on_redirect=False``.

    :param int status:
        How many times to retry on bad status codes.

        These are retries made on responses, where status code matches
        ``status_forcelist``.

        Set to ``0`` to fail on the first retry of this type.

    :param int other:
        How many times to retry on other errors.

        Other errors are errors that are not connect, read, redirect or status errors.
        These errors might be raised after the request was sent to the server, so the
        request might have side-effects.

        Set to ``0`` to fail on the first retry of this type.

        If ``total`` is not set, it's a good idea to set this to 0 to account
        for unexpected edge cases and avoid infinite retry loops.

    :param iterable allowed_methods:
        Set of uppercased HTTP method verbs that we should retry on.

        By default, we only retry on methods which are considered to be
        idempotent (multiple requests with the same parameters end with the
        same state). See :attr:`Retry.DEFAULT_ALLOWED_METHODS`.

        Set to a ``False`` value to retry on any verb.

        .. warning::

            Previously this parameter was named ``method_whitelist``, that
            usage is deprecated in v1.26.0 and will be removed in v2.0.

    :param iterable status_forcelist:
        A set of integer HTTP status codes that we should force a retry on.
        A retry is initiated if the request method is in ``allowed_methods``
        and the response status code is in ``status_forcelist``.

        By default, this is disabled with ``None``.

    :param float backoff_factor:
        A backoff factor to apply between attempts after the second try
        (most errors are resolved immediately by a second try without a
        delay). urllib3 will sleep for::

            {backoff factor} * (2 ** ({number of total retries} - 1))

        seconds. If the backoff_factor is 0.1, then :func:`.sleep` will sleep
        for [0.0s, 0.2s, 0.4s, ...] between retries. It will never be longer
        than :attr:`Retry.BACKOFF_MAX`.

        By default, backoff is disabled (set to 0).

    :param bool raise_on_redirect: Whether, if the number of redirects is
        exhausted, to raise a MaxRetryError, or to return a response with a
        response code in the 3xx range.

    :param bool raise_on_status: Similar meaning to ``raise_on_redirect``:
        whether we should raise an exception, or return a response,
        if status falls in ``status_forcelist`` range and retries have
        been exhausted.

    :param tuple history: The history of the request encountered during
        each call to :meth:`~Retry.increment`. The list is in the order
        the requests occurred. Each list item is of class :class:`RequestHistory`.

    :param bool respect_retry_after_header:
        Whether to respect Retry-After header on status codes defined as
        :attr:`Retry.RETRY_AFTER_STATUS_CODES` or not.

    :param iterable remove_headers_on_redirect:
        Sequence of headers to remove from the request when a response
        indicating a redirect is returned before firing off the redirected
        request.
    """

    #: Default methods to be used for ``allowed_methods``
    DEFAULT_ALLOWED_METHODS = frozenset(
        ["HEAD", "GET", "PUT", "DELETE", "OPTIONS", "TRACE"]
    )

    #: Default status codes to be used for ``status_forcelist``
    RETRY_AFTER_STATUS_CODES = frozenset([413, 429, 503])

    #: Default headers to be used for ``remove_headers_on_redirect``
    DEFAULT_REMOVE_HEADERS_ON_REDIRECT = frozenset(["Authorization"])

    #: Maximum backoff time.
    BACKOFF_MAX = 120

    def __init__(
        self,
        total=10,
        connect=None,
        read=None,
        redirect=None,
        status=None,
        other=None,
        allowed_methods=_Default,
        status_forcelist=None,
        backoff_factor=0,
        raise_on_redirect=True,
        raise_on_status=True,
        history=None,
        respect_retry_after_header=True,
        remove_headers_on_redirect=_Default,
        # TODO: Deprecated, remove in v2.0
        method_whitelist=_Default,
    ):

        if method_whitelist is not _Default:
            if allowed_methods is not _Default:
                raise ValueError(
                    "Using both 'allowed_methods' and "
                    "'method_whitelist' together is not allowed. "
                    "Instead only use 'allowed_methods'"
                )
            warnings.warn(
                "Using 'method_whitelist' with Retry is deprecated and "
                "will be removed in v2.0. Use 'allowed_methods' instead",
                DeprecationWarning,
                stacklevel=2,
            )
            allowed_methods = method_whitelist
        if allowed_methods is _Default:
            allowed_methods = self.DEFAULT_ALLOWED_METHODS
        if remove_headers_on_redirect is _Default:
            remove_headers_on_redirect = self.DEFAULT_REMOVE_HEADERS_ON_REDIRECT

        self.total = total
        self.connect = connect
        self.read = read
        self.status = status
        self.other = other

        if redirect is False or total is False:
            redirect = 0
            raise_on_redirect = False

        self.redirect = redirect
        self.status_forcelist = status_forcelist or set()
        self.allowed_methods = allowed_methods
        self.backoff_factor = backoff_factor
        self.raise_on_redirect = raise_on_redirect
        self.raise_on_status = raise_on_status
        self.history = history or tuple()
        self.respect_retry_after_header = respect_retry_after_header
        self.remove_headers_on_redirect = frozenset(
            [h.lower() for h in remove_headers_on_redirect]
        )

    def new(self, **kw):
        params = dict(
            total=self.total,
            connect=self.connect,
            read=self.read,
            redirect=self.redirect,
            status=self.status,
            other=self.other,
            status_forcelist=self.status_forcelist,
            backoff_factor=self.backoff_factor,
            raise_on_redirect=self.raise_on_redirect,
            raise_on_status=self.raise_on_status,
            history=self.history,
            remove_headers_on_redirect=self.remove_headers_on_redirect,
            respect_retry_after_header=self.respect_retry_after_header,
        )

        # TODO: If already given in **kw we use what's given to us
        # If not given we need to figure out what to pass. We decide
        # based on whether our class has the 'method_whitelist' property
        # and if so we pass the deprecated 'method_whitelist' otherwise
        # we use 'allowed_methods'. Remove in v2.0
        if "method_whitelist" not in kw and "allowed_methods" not in kw:
            if "method_whitelist" in self.__dict__:
                warnings.warn(
                    "Using 'method_whitelist' with Retry is deprecated and "
                    "will be removed in v2.0. Use 'allowed_methods' instead",
                    DeprecationWarning,
                )
                params["method_whitelist"] = self.allowed_methods
            else:
                params["allowed_methods"] = self.allowed_methods

        params.update(kw)
        return type(self)(**params)

    @classmethod
    def from_int(cls, retries, redirect=True, default=None):
        """Backwards-compatibility for the old retries format."""
        if retries is None:
            retries = default if default is not None else cls.DEFAULT

        if isinstance(retries, Retry):
            return retries

        redirect = bool(redirect) and None
        new_retries = cls(retries, redirect=redirect)
        log.debug("Converted retries value: %r -> %r", retries, new_retries)
        return new_retries

    def get_backoff_time(self):
        """Formula for computing the current backoff

        :rtype: float
        """
        # We want to consider only the last consecutive errors sequence (Ignore redirects).
        consecutive_errors_len = len(
            list(
                takewhile(lambda x: x.redirect_location is None, reversed(self.history))
            )
        )
        if consecutive_errors_len <= 1:
            return 0

        backoff_value = self.backoff_factor * (2 ** (consecutive_errors_len - 1))
        return min(self.BACKOFF_MAX, backoff_value)

    def parse_retry_after(self, retry_after):
        # Whitespace: https://tools.ietf.org/html/rfc7230#section-3.2.4
        if re.match(r"^\s*[0-9]+\s*$", retry_after):
            seconds = int(retry_after)
        else:
            retry_date_tuple = email.utils.parsedate_tz(retry_after)
            if retry_date_tuple is None:
                raise InvalidHeader("Invalid Retry-After header: %s" % retry_after)
            if retry_date_tuple[9] is None:  # Python 2
                # Assume UTC if no timezone was specified
                # On Python2.7, parsedate_tz returns None for a timezone offset
                # instead of 0 if no timezone is given, where mktime_tz treats
                # a None timezone offset as local time.
                retry_date_tuple = retry_date_tuple[:9] + (0,) + retry_date_tuple[10:]

            retry_date = email.utils.mktime_tz(retry_date_tuple)
            seconds = retry_date - time.time()

        if seconds < 0:
            seconds = 0

        return seconds

    def get_retry_after(self, response):
        """Get the value of Retry-After in seconds."""

        retry_after = response.getheader("Retry-After")

        if retry_after is None:
            return None

        return self.parse_retry_after(retry_after)

    def sleep_for_retry(self, response=None):
        retry_after = self.get_retry_after(response)
        if retry_after:
            time.sleep(retry_after)
            return True

        return False

    def _sleep_backoff(self):
        backoff = self.get_backoff_time()
        if backoff <= 0:
            return
        time.sleep(backoff)

    def sleep(self, response=None):
        """Sleep between retry attempts.

        This method will respect a server's ``Retry-After`` response header
        and sleep the duration of the time requested. If that is not present, it
        will use an exponential backoff. By default, the backoff factor is 0 and
        this method will return immediately.
        """

        if self.respect_retry_after_header and response:
            slept = self.sleep_for_retry(response)
            if slept:
                return

        self._sleep_backoff()

    def _is_connection_error(self, err):
        """Errors when we're fairly sure that the server did not receive the
        request, so it should be safe to retry.
        """
        if isinstance(err, ProxyError):
            err = err.original_error
        return isinstance(err, ConnectTimeoutError)

    def _is_read_error(self, err):
        """Errors that occur after the request has been started, so we should
        assume that the server began processing it.
        """
        return isinstance(err, (ReadTimeoutError, ProtocolError))

    def _is_method_retryable(self, method):
        """Checks if a given HTTP method should be retried upon, depending if
        it is included in the allowed_methods
        """
        # TODO: For now favor if the Retry implementation sets its own method_whitelist
        # property outside of our constructor to avoid breaking custom implementations.
        if "method_whitelist" in self.__dict__:
            warnings.warn(
                "Using 'method_whitelist' with Retry is deprecated and "
                "will be removed in v2.0. Use 'allowed_methods' instead",
                DeprecationWarning,
            )
            allowed_methods = self.method_whitelist
        else:
            allowed_methods = self.allowed_methods

        if allowed_methods and method.upper() not in allowed_methods:
            return False
        return True

    def is_retry(self, method, status_code, has_retry_after=False):
        """Is this method/status code retryable? (Based on allowlists and control
        variables such as the number of total retries to allow, whether to
        respect the Retry-After header, whether this header is present, and
        whether the returned status code is on the list of status codes to
        be retried upon on the presence of the aforementioned header)
        """
        if not self._is_method_retryable(method):
            return False

        if self.status_forcelist and status_code in self.status_forcelist:
            return True

        return (
            self.total
            and self.respect_retry_after_header
            and has_retry_after
            and (status_code in self.RETRY_AFTER_STATUS_CODES)
        )

    def is_exhausted(self):
        """Are we out of retries?"""
        retry_counts = (
            self.total,
            self.connect,
            self.read,
            self.redirect,
            self.status,
            self.other,
        )
        retry_counts = list(filter(None, retry_counts))
        if not retry_counts:
            return False

        return min(retry_counts) < 0

    def increment(
        self,
        method=None,
        url=None,
        response=None,
        error=None,
        _pool=None,
        _stacktrace=None,
    ):
        """Return a new Retry object with incremented retry counters.

        :param response: A response object, or None, if the server did not
            return a response.
        :type response: :class:`~urllib3.response.HTTPResponse`
        :param Exception error: An error encountered during the request, or
            None if the response was received successfully.

        :return: A new ``Retry`` object.
        """
        if self.total is False and error:
            # Disabled, indicate to re-raise the error.
            raise six.reraise(type(error), error, _stacktrace)

        total = self.total
        if total is not None:
            total -= 1

        connect = self.connect
        read = self.read
        redirect = self.redirect
        status_count = self.status
        other = self.other
        cause = "unknown"
        status = None
        redirect_location = None

        if error and self._is_connection_error(error):
            # Connect retry?
            if connect is False:
                raise six.reraise(type(error), error, _stacktrace)
            elif connect is not None:
                connect -= 1

        elif error and self._is_read_error(error):
            # Read retry?
            if read is False or not self._is_method_retryable(method):
                raise six.reraise(type(error), error, _stacktrace)
            elif read is not None:
                read -= 1

        elif error:
            # Other retry?
            if other is not None:
                other -= 1

        elif response and response.get_redirect_location():
            # Redirect retry?
            if redirect is not None:
                redirect -= 1
            cause = "too many redirects"
            redirect_location = response.get_redirect_location()
            status = response.status

        else:
            # Incrementing because of a server error like a 500 in
            # status_forcelist and the given method is in the allowed_methods
            cause = ResponseError.GENERIC_ERROR
            if response and response.status:
                if status_count is not None:
                    status_count -= 1
                cause = ResponseError.SPECIFIC_ERROR.format(status_code=response.status)
                status = response.status

        history = self.history + (
            RequestHistory(method, url, error, status, redirect_location),
        )

        new_retry = self.new(
            total=total,
            connect=connect,
            read=read,
            redirect=redirect,
            status=status_count,
            other=other,
            history=history,
        )

        if new_retry.is_exhausted():
            raise MaxRetryError(_pool, url, error or ResponseError(cause))

        log.debug("Incremented Retry for (url='%s'): %r", url, new_retry)

        return new_retry

    def __repr__(self):
        return (
            "{cls.__name__}(total={self.total}, connect={self.connect}, "
            "read={self.read}, redirect={self.redirect}, status={self.status})"
        ).format(cls=type(self), self=self)

    def __getattr__(self, item):
        if item == "method_whitelist":
            # TODO: Remove this deprecated alias in v2.0
            warnings.warn(
                "Using 'method_whitelist' with Retry is deprecated and "
                "will be removed in v2.0. Use 'allowed_methods' instead",
                DeprecationWarning,
            )
            return self.allowed_methods
        try:
            return getattr(super(Retry, self), item)
        except AttributeError:
            return getattr(Retry, item)

class Timeout(object):
    """Timeout configuration.

    Timeouts can be defined as a default for a pool:

    .. code-block:: python

       timeout = Timeout(connect=2.0, read=7.0)
       http = PoolManager(timeout=timeout)
       response = http.request('GET', 'http://example.com/')

    Or per-request (which overrides the default for the pool):

    .. code-block:: python

       response = http.request('GET', 'http://example.com/', timeout=Timeout(10))

    Timeouts can be disabled by setting all the parameters to ``None``:

    .. code-block:: python

       no_timeout = Timeout(connect=None, read=None)
       response = http.request('GET', 'http://example.com/, timeout=no_timeout)


    :param total:
        This combines the connect and read timeouts into one; the read timeout
        will be set to the time leftover from the connect attempt. In the
        event that both a connect timeout and a total are specified, or a read
        timeout and a total are specified, the shorter timeout will be applied.

        Defaults to None.

    :type total: int, float, or None

    :param connect:
        The maximum amount of time (in seconds) to wait for a connection
        attempt to a server to succeed. Omitting the parameter will default the
        connect timeout to the system default, probably `the global default
        timeout in socket.py
        <http://hg.python.org/cpython/file/603b4d593758/Lib/socket.py#l535>`_.
        None will set an infinite timeout for connection attempts.

    :type connect: int, float, or None

    :param read:
        The maximum amount of time (in seconds) to wait between consecutive
        read operations for a response from the server. Omitting the parameter
        will default the read timeout to the system default, probably `the
        global default timeout in socket.py
        <http://hg.python.org/cpython/file/603b4d593758/Lib/socket.py#l535>`_.
        None will set an infinite timeout.

    :type read: int, float, or None

    .. note::

        Many factors can affect the total amount of time for urllib3 to return
        an HTTP response.

        For example, Python's DNS resolver does not obey the timeout specified
        on the socket. Other factors that can affect total request time include
        high CPU load, high swap, the program running at a low priority level,
        or other behaviors.

        In addition, the read and total timeouts only measure the time between
        read operations on the socket connecting the client and the server,
        not the total amount of time for the request to return a complete
        response. For most requests, the timeout is raised because the server
        has not sent the first byte in the specified time. This is not always
        the case; if a server streams one byte every fifteen seconds, a timeout
        of 20 seconds will not trigger, even though the request will take
        several minutes to complete.

        If your goal is to cut off any request after a set amount of wall clock
        time, consider having a second "watcher" thread to cut off a slow
        request.
    """

    #: A sentinel object representing the default timeout value
    DEFAULT_TIMEOUT = _GLOBAL_DEFAULT_TIMEOUT

    def __init__(self, total=None, connect=_Default, read=_Default):
        self._connect = self._validate_timeout(connect, "connect")
        self._read = self._validate_timeout(read, "read")
        self.total = self._validate_timeout(total, "total")
        self._start_connect = None

    def __repr__(self):
        return "%s(connect=%r, read=%r, total=%r)" % (
            type(self).__name__,
            self._connect,
            self._read,
            self.total,
        )

    # __str__ provided for backwards compatibility
    __str__ = __repr__

    @classmethod
    def _validate_timeout(cls, value, name):
        """Check that a timeout attribute is valid.

        :param value: The timeout value to validate
        :param name: The name of the timeout attribute to validate. This is
            used to specify in error messages.
        :return: The validated and casted version of the given value.
        :raises ValueError: If it is a numeric value less than or equal to
            zero, or the type is not an integer, float, or None.
        """
        if value is _Default:
            return cls.DEFAULT_TIMEOUT

        if value is None or value is cls.DEFAULT_TIMEOUT:
            return value

        if isinstance(value, bool):
            raise ValueError(
                "Timeout cannot be a boolean value. It must "
                "be an int, float or None."
            )
        try:
            float(value)
        except (TypeError, ValueError):
            raise ValueError(
                "Timeout value %s was %s, but it must be an "
                "int, float or None." % (name, value)
            )

        try:
            if value <= 0:
                raise ValueError(
                    "Attempted to set %s timeout to %s, but the "
                    "timeout cannot be set to a value less "
                    "than or equal to 0." % (name, value)
                )
        except TypeError:
            # Python 3
            raise ValueError(
                "Timeout value %s was %s, but it must be an "
                "int, float or None." % (name, value)
            )

        return value

    @classmethod
    def from_float(cls, timeout):
        """Create a new Timeout from a legacy timeout value.

        The timeout value used by httplib.py sets the same timeout on the
        connect(), and recv() socket requests. This creates a :class:`Timeout`
        object that sets the individual timeouts to the ``timeout`` value
        passed to this function.

        :param timeout: The legacy timeout value.
        :type timeout: integer, float, sentinel default object, or None
        :return: Timeout object
        :rtype: :class:`Timeout`
        """
        return Timeout(read=timeout, connect=timeout)

    def clone(self):
        """Create a copy of the timeout object

        Timeout properties are stored per-pool but each request needs a fresh
        Timeout object to ensure each one has its own start/stop configured.

        :return: a copy of the timeout object
        :rtype: :class:`Timeout`
        """
        # We can't use copy.deepcopy because that will also create a new object
        # for _GLOBAL_DEFAULT_TIMEOUT, which socket.py uses as a sentinel to
        # detect the user default.
        return Timeout(connect=self._connect, read=self._read, total=self.total)

    def start_connect(self):
        """Start the timeout clock, used during a connect() attempt

        :raises urllib3.exceptions.TimeoutStateError: if you attempt
            to start a timer that has been started already.
        """
        if self._start_connect is not None:
            raise TimeoutStateError("Timeout timer has already been started.")
        self._start_connect = current_time()
        return self._start_connect

    def get_connect_duration(self):
        """Gets the time elapsed since the call to :meth:`start_connect`.

        :return: Elapsed time in seconds.
        :rtype: float
        :raises urllib3.exceptions.TimeoutStateError: if you attempt
            to get duration for a timer that hasn't been started.
        """
        if self._start_connect is None:
            raise TimeoutStateError(
                "Can't get connect duration for timer that has not started."
            )
        return current_time() - self._start_connect

    @property
    def connect_timeout(self):
        """Get the value to use when setting a connection timeout.

        This will be a positive float or integer, the value None
        (never timeout), or the default system timeout.

        :return: Connect timeout.
        :rtype: int, float, :attr:`Timeout.DEFAULT_TIMEOUT` or None
        """
        if self.total is None:
            return self._connect

        if self._connect is None or self._connect is self.DEFAULT_TIMEOUT:
            return self.total

        return min(self._connect, self.total)

    @property
    def read_timeout(self):
        """Get the value for the read timeout.

        This assumes some time has elapsed in the connection timeout and
        computes the read timeout appropriately.

        If self.total is set, the read timeout is dependent on the amount of
        time taken by the connect timeout. If the connection time has not been
        established, a :exc:`~urllib3.exceptions.TimeoutStateError` will be
        raised.

        :return: Value to use for the read timeout.
        :rtype: int, float, :attr:`Timeout.DEFAULT_TIMEOUT` or None
        :raises urllib3.exceptions.TimeoutStateError: If :meth:`start_connect`
            has not yet been called on this object.
        """
        if (
            self.total is not None
            and self.total is not self.DEFAULT_TIMEOUT
            and self._read is not None
            and self._read is not self.DEFAULT_TIMEOUT
        ):
            # In case the connect timeout has not yet been established.
            if self._start_connect is None:
                return self._read
            return max(0, min(self.total - self.get_connect_duration(), self._read))
        elif self.total is not None and self.total is not self.DEFAULT_TIMEOUT:
            return max(0, self.total - self.get_connect_duration())
        else:
            return self._read

class Url(namedtuple("Url", url_attrs)):
    """
    Data structure for representing an HTTP URL. Used as a return value for
    :func:`parse_url`. Both the scheme and host are normalized as they are
    both case-insensitive according to RFC 3986.
    """

    __slots__ = ()

    def __new__(
        cls,
        scheme=None,
        auth=None,
        host=None,
        port=None,
        path=None,
        query=None,
        fragment=None,
    ):
        if path and not path.startswith("/"):
            path = "/" + path
        if scheme is not None:
            scheme = scheme.lower()
        return super(Url, cls).__new__(
            cls, scheme, auth, host, port, path, query, fragment
        )

    @property
    def hostname(self):
        """For backwards-compatibility with urlparse. We're nice like that."""
        return self.host

    @property
    def request_uri(self):
        """Absolute path including the query string."""
        uri = self.path or "/"

        if self.query is not None:
            uri += "?" + self.query

        return uri

    @property
    def netloc(self):
        """Network location including host and port"""
        if self.port:
            return "%s:%d" % (self.host, self.port)
        return self.host

    @property
    def url(self):
        """
        Convert self into a url

        This function should more or less round-trip with :func:`.parse_url`. The
        returned url may not be exactly the same as the url inputted to
        :func:`.parse_url`, but it should be equivalent by the RFC (e.g., urls
        with a blank port will have : removed).

        Example: ::

            >>> U = parse_url('http://google.com/mail/')
            >>> U.url
            'http://google.com/mail/'
            >>> Url('http', 'username:password', 'host.com', 80,
            ... '/path', 'query', 'fragment').url
            'http://username:password@host.com:80/path?query#fragment'
        """
        scheme, auth, host, port, path, query, fragment = self
        url = u""

        # We use "is not None" we want things to happen with empty strings (or 0 port)
        if scheme is not None:
            url += scheme + u"://"
        if auth is not None:
            url += auth + u"@"
        if host is not None:
            url += host
        if port is not None:
            url += u":" + str(port)
        if path is not None:
            url += path
        if query is not None:
            url += u"?" + query
        if fragment is not None:
            url += u"#" + fragment

        return url

    def __str__(self):
        return self.url