Tornado 测试——通过备选 IP 访问 localhost

Question

我发现龙卷风发生了一些非常奇怪的事情


from tornado.web import Application
from tornado.testing import AsyncHTTPTestCase
import requests
import tornado
from tornado.ioloop import IOLoop

class MyTest(AsyncHTTPTestCase):
    def get_app(self):
        return Application()

    @tornado.testing.gen_test(timeout=30)
    async def test_pass(self):

        response = await IOLoop.current().run_in_executor(None, requests.get,"http://127.0.0.1:" + str(self.get_http_port()) + "/foo")
        print(response)

    @tornado.testing.gen_test(timeout=30)
    async def test_fail(self):
        response = await IOLoop.current().run_in_executor(None, requests.get,"http://192.168.2.1:" + str(self.get_http_port()) + "/foo")
        print(response)

第一个测试通过，而第二个测试失败

_____________________________________________________________ MyTest.test_fail _____________________________________________________________

self = <urllib3.connection.HTTPConnection object at 0x7fea40367e50>

    def _new_conn(self):
        """Establish a socket connection and set nodelay settings on it.
    
        :return: New socket connection.
        """
        extra_kw = {}
        if self.source_address:
            extra_kw["source_address"] = self.source_address
    
        if self.socket_options:
            extra_kw["socket_options"] = self.socket_options
    
        try:
            conn = connection.create_connection(
>               (self._dns_host, self.port), self.timeout, **extra_kw
            )

../.virtualenvs/creative-preview/lib/python3.7/site-packages/urllib3/connection.py:170: 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 

address = ('192.168.2.1', 41809), timeout = None, source_address = None, socket_options = [(6, 1, 1)]

    def create_connection(
        address,
        timeout=socket._GLOBAL_DEFAULT_TIMEOUT,
        source_address=None,
        socket_options=None,
    ):
        """Connect to *address* and return the socket object.
    
        Convenience function.  Connect to *address* (a 2-tuple ``(host,
        port)``) and return the socket object.  Passing the optional
        *timeout* parameter will set the timeout on the socket instance
        before attempting to connect.  If no *timeout* is supplied, the
        global default timeout setting returned by :func:`socket.getdefaulttimeout`
        is used.  If *source_address* is set it must be a tuple of (host, port)
        for the socket to bind as a source address before making the connection.
        An host of '' or port 0 tells the OS to use the default.
        """
    
        host, port = address
        if host.startswith("["):
            host = host.strip("[]")
        err = None
    
        # Using the value from allowed_gai_family() in the context of getaddrinfo lets
        # us select whether to work with IPv4 DNS records, IPv6 records, or both.
        # The original create_connection function always returns all records.
        family = allowed_gai_family()
    
        try:
            host.encode("idna")
        except UnicodeError:
            return six.raise_from(
                LocationParseError(u"'%s', label empty or too long" % host), None
            )
    
        for res in socket.getaddrinfo(host, port, family, socket.SOCK_STREAM):
            af, socktype, proto, canonname, sa = res
            sock = None
            try:
                sock = socket.socket(af, socktype, proto)
    
                # If provided, set socket level options before connecting.
                _set_socket_options(sock, socket_options)
    
                if timeout is not socket._GLOBAL_DEFAULT_TIMEOUT:
                    sock.settimeout(timeout)
                if source_address:
                    sock.bind(source_address)
                sock.connect(sa)
                return sock
    
            except socket.error as e:
                err = e
                if sock is not None:
                    sock.close()
                    sock = None
    
        if err is not None:
>           raise err

../.virtualenvs/creative-preview/lib/python3.7/site-packages/urllib3/util/connection.py:96: 

...

During handling of the above exception, another exception occurred:

self = <my_test.MyTest testMethod=test_fail>

    @tornado.testing.gen_test(timeout=30)
    async def test_fail(self):
>       response = await IOLoop.current().run_in_executor(None, requests.get,"http://192.168.2.1:" + str(self.get_http_port()) + "/foo")

my_test.py:18: 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
/usr/lib/python3.7/concurrent/futures/thread.py:57: in run
    result = self.fn(*self.args, **self.kwargs)
../.virtualenvs/creative-preview/lib/python3.7/site-packages/requests/api.py:76: in get
    return request('get', url, params=params, **kwargs)
../.virtualenvs/creative-preview/lib/python3.7/site-packages/requests/api.py:61: in request
    return session.request(method=method, url=url, **kwargs)
../.virtualenvs/creative-preview/lib/python3.7/site-packages/requests/sessions.py:542: in request
    resp = self.send(prep, **send_kwargs)
../.virtualenvs/creative-preview/lib/python3.7/site-packages/requests/sessions.py:655: in send
    r = adapter.send(request, **kwargs)
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 

self = <requests.adapters.HTTPAdapter object at 0x7fea4034dbd0>, request = <PreparedRequest [GET]>, stream = False
timeout = Timeout(connect=None, read=None, total=None), verify = True, cert = None, proxies = OrderedDict()

    def send(self, request, stream=False, timeout=None, verify=True, cert=None, proxies=None):
        """Sends PreparedRequest object. Returns Response object.
    
        :param request: The :class:`PreparedRequest <PreparedRequest>` being sent.
        :param stream: (optional) Whether to stream the request content.
        :param timeout: (optional) How long to wait for the server to send
            data before giving up, as a float, or a :ref:`(connect timeout,
            read timeout) <timeouts>` tuple.
        :type timeout: float or tuple or urllib3 Timeout object
        :param verify: (optional) Either a boolean, in which case it controls whether
            we verify the server's TLS certificate, or a string, in which case it
            must be a path to a CA bundle to use
        :param cert: (optional) Any user-provided SSL certificate to be trusted.
        :param proxies: (optional) The proxies dictionary to apply to the request.
        :rtype: requests.Response
        """
    
        try:
            conn = self.get_connection(request.url, proxies)
        except LocationValueError as e:
            raise InvalidURL(e, request=request)
    
        self.cert_verify(conn, request.url, verify, cert)
        url = self.request_url(request, proxies)
        self.add_headers(request, stream=stream, timeout=timeout, verify=verify, cert=cert, proxies=proxies)
    
        chunked = not (request.body is None or 'Content-Length' in request.headers)
    
        if isinstance(timeout, tuple):
            try:
                connect, read = timeout
                timeout = TimeoutSauce(connect=connect, read=read)
            except ValueError as e:
                # this may raise a string formatting error.
                err = ("Invalid timeout {}. Pass a (connect, read) "
                       "timeout tuple, or a single float to set "
                       "both timeouts to the same value".format(timeout))
                raise ValueError(err)
        elif isinstance(timeout, TimeoutSauce):
            pass
        else:
            timeout = TimeoutSauce(connect=timeout, read=timeout)
    
        try:
            if not chunked:
                resp = conn.urlopen(
                    method=request.method,
                    url=url,
                    body=request.body,
                    headers=request.headers,
                    redirect=False,
                    assert_same_host=False,
                    preload_content=False,
                    decode_content=False,
                    retries=self.max_retries,
                    timeout=timeout
                )
    
            # Send the request.
            else:
                if hasattr(conn, 'proxy_pool'):
                    conn = conn.proxy_pool
    
                low_conn = conn._get_conn(timeout=DEFAULT_POOL_TIMEOUT)
    
                try:
                    low_conn.putrequest(request.method,
                                        url,
                                        skip_accept_encoding=True)
    
                    for header, value in request.headers.items():
                        low_conn.putheader(header, value)
    
                    low_conn.endheaders()
    
                    for i in request.body:
                        low_conn.send(hex(len(i))[2:].encode('utf-8'))
                        low_conn.send(b'\r\n')
                        low_conn.send(i)
                        low_conn.send(b'\r\n')
                    low_conn.send(b'0\r\n\r\n')
    
                    # Receive the response from the server
                    try:
                        # For Python 2.7, use buffering of HTTP responses
                        r = low_conn.getresponse(buffering=True)
                    except TypeError:
                        # For compatibility with Python 3.3+
                        r = low_conn.getresponse()
    
                    resp = HTTPResponse.from_httplib(
                        r,
                        pool=conn,
                        connection=low_conn,
                        preload_content=False,
                        decode_content=False
                    )
                except:
                    # If we hit any problems here, clean up the connection.
                    # Then, reraise so that we can handle the actual exception.
                    low_conn.close()
                    raise
    
        except (ProtocolError, socket.error) as err:
            raise ConnectionError(err, request=request)
    
        except MaxRetryError as e:
            if isinstance(e.reason, ConnectTimeoutError):
                # TODO: Remove this in 3.0.0: see #2811
                if not isinstance(e.reason, NewConnectionError):
                    raise ConnectTimeout(e, request=request)
    
            if isinstance(e.reason, ResponseError):
                raise RetryError(e, request=request)
    
            if isinstance(e.reason, _ProxyError):
                raise ProxyError(e, request=request)
    
            if isinstance(e.reason, _SSLError):
                # This branch is for urllib3 v1.22 and later.
                raise SSLError(e, request=request)
    
>           raise ConnectionError(e, request=request)
E           requests.exceptions.ConnectionError: HTTPConnectionPool(host='192.168.2.1', port=41809): Max retries exceeded with url: /foo (Caused by NewConnectionError('<urllib3.connection.HTTPConnection object at 0x7fea40367e50>: Failed to establish a new connection: [Errno 111] Connection refused'))

../.virtualenvs/creative-preview/lib/python3.7/site-packages/requests/adapters.py:516: ConnectionError
==================================================== 1 failed, 1 passed in 0.22 seconds ==================================================

192.168.2.1 也是本地主机（通过 docker0 接口）。奇怪的是，如果我运行一个简单的 http 服务器 python -m http.server 然后 curl 127.0.0.1:8000 和 curl 192.168.2.1:8000 both 工作，所以它不这似乎是一个 docker 相关的问题。所以我真的不知道怎么回事

Answer 1

您可以尝试 curl -v 192.168.2.1:8000（详细）并检查输出吗？也许您被重定向到本地主机，而您的代码中并未发生这种情况。

您的应用监听主机是什么？本地主机或 0.0.0.0?

如果您希望能够从本地计算机连接，您需要确保您正在收听 0.0.0.0。

Tornado 测试——通过备选 IP 访问 localhost

Tornado test - access localhost through alternative IP

python

tornado

docker