def check(self, value):
     self.assertEqual(format_timestamp(value), self.EXPECTED)
    def __init__(self, url, method="GET", headers=None, body=None,
                 auth_username=None, auth_password=None, auth_mode=None,
                 connect_timeout=None, request_timeout=None,
                 if_modified_since=None, follow_redirects=None,
                 max_redirects=None, user_agent=None, use_gzip=None,
                 network_interface=None, streaming_callback=None,
                 header_callback=None, prepare_curl_callback=None,
                 proxy_host=None, proxy_port=None, proxy_username=None,
                 proxy_password=None, allow_nonstandard_methods=None,
                 validate_cert=None, ca_certs=None,
                 allow_ipv6=None,
                 client_key=None, client_cert=None):
        r"""All parameters except ``url`` are optional.

        :arg string url: URL to fetch
        :arg string method: HTTP method, e.g. "GET" or "POST"
        :arg headers: Additional HTTP headers to pass on the request
        :arg body: HTTP body to pass on the request
        :type headers: `~webalchemy.tornado.httputil.HTTPHeaders` or `dict`
        :arg string auth_username: Username for HTTP authentication
        :arg string auth_password: Password for HTTP authentication
        :arg string auth_mode: Authentication mode; default is "basic".
           Allowed values are implementation-defined; ``curl_httpclient``
           supports "basic" and "digest"; ``simple_httpclient`` only supports
           "basic"
        :arg float connect_timeout: Timeout for initial connection in seconds
        :arg float request_timeout: Timeout for entire request in seconds
        :arg if_modified_since: Timestamp for ``If-Modified-Since`` header
        :type if_modified_since: `datetime` or `float`
        :arg bool follow_redirects: Should redirects be followed automatically
           or return the 3xx response?
        :arg int max_redirects: Limit for ``follow_redirects``
        :arg string user_agent: String to send as ``User-Agent`` header
        :arg bool use_gzip: Request gzip encoding from the server
        :arg string network_interface: Network interface to use for request.
           ``curl_httpclient`` only; see note below.
        :arg callable streaming_callback: If set, ``streaming_callback`` will
           be run with each chunk of data as it is received, and
           ``HTTPResponse.body`` and ``HTTPResponse.buffer`` will be empty in
           the final response.
        :arg callable header_callback: If set, ``header_callback`` will
           be run with each header line as it is received (including the
           first line, e.g. ``HTTP/1.0 200 OK\r\n``, and a final line
           containing only ``\r\n``.  All lines include the trailing newline
           characters).  ``HTTPResponse.headers`` will be empty in the final
           response.  This is most useful in conjunction with
           ``streaming_callback``, because it's the only way to get access to
           header data while the request is in progress.
        :arg callable prepare_curl_callback: If set, will be called with
           a ``pycurl.Curl`` object to allow the application to make additional
           ``setopt`` calls.
        :arg string proxy_host: HTTP proxy hostname.  To use proxies,
           ``proxy_host`` and ``proxy_port`` must be set; ``proxy_username`` and
           ``proxy_pass`` are optional.  Proxies are currently only supported
           with ``curl_httpclient``.
        :arg int proxy_port: HTTP proxy port
        :arg string proxy_username: HTTP proxy username
        :arg string proxy_password: HTTP proxy password
        :arg bool allow_nonstandard_methods: Allow unknown values for ``method``
           argument?
        :arg bool validate_cert: For HTTPS requests, validate the server's
           certificate?
        :arg string ca_certs: filename of CA certificates in PEM format,
           or None to use defaults.  See note below when used with
           ``curl_httpclient``.
        :arg bool allow_ipv6: Use IPv6 when available?  Default is false in
           ``simple_httpclient`` and true in ``curl_httpclient``
        :arg string client_key: Filename for client SSL key, if any.  See
           note below when used with ``curl_httpclient``.
        :arg string client_cert: Filename for client SSL certificate, if any.
           See note below when used with ``curl_httpclient``.

        .. note::

            When using ``curl_httpclient`` certain options may be
            inherited by subsequent fetches because ``pycurl`` does
            not allow them to be cleanly reset.  This applies to the
            ``ca_certs``, ``client_key``, ``client_cert``, and
            ``network_interface`` arguments.  If you use these
            options, you should pass them on every request (you don't
            have to always use the same values, but it's not possible
            to mix requests that specify these options with ones that
            use the defaults).

        .. versionadded:: 3.1
           The ``auth_mode`` argument.
        """
        # Note that some of these attributes go through property setters
        # defined below.
        self.headers = headers
        if if_modified_since:
            self.headers["If-Modified-Since"] = httputil.format_timestamp(
                if_modified_since)
        self.proxy_host = proxy_host
        self.proxy_port = proxy_port
        self.proxy_username = proxy_username
        self.proxy_password = proxy_password
        self.url = url
        self.method = method
        self.body = body
        self.auth_username = auth_username
        self.auth_password = auth_password
        self.auth_mode = auth_mode
        self.connect_timeout = connect_timeout
        self.request_timeout = request_timeout
        self.follow_redirects = follow_redirects
        self.max_redirects = max_redirects
        self.user_agent = user_agent
        self.use_gzip = use_gzip
        self.network_interface = network_interface
        self.streaming_callback = streaming_callback
        self.header_callback = header_callback
        self.prepare_curl_callback = prepare_curl_callback
        self.allow_nonstandard_methods = allow_nonstandard_methods
        self.validate_cert = validate_cert
        self.ca_certs = ca_certs
        self.allow_ipv6 = allow_ipv6
        self.client_key = client_key
        self.client_cert = client_cert
        self.start_time = time.time()