test_socketlevel.py

# TODO: Break this module up into pieces. Maybe group by functionality tested
# rather than the socket level-ness of it.
from urllib3 import HTTPConnectionPool, HTTPSConnectionPool
from urllib3.poolmanager import proxy_from_url
from urllib3.exceptions import (
    MaxRetryError,
    ProxyError,
    ReadTimeoutError,
    SSLError,
    ProtocolError,
)
from urllib3.packages.six.moves import http_client as httplib
from urllib3 import util
from urllib3.util import ssl_wrap_socket
from urllib3.util import ssl_
from urllib3.util.timeout import Timeout
from urllib3.util.retry import Retry
from urllib3._collections import HTTPHeaderDict

from dummyserver.testcase import SocketDummyServerTestCase, consume_socket
from dummyserver.server import (
    DEFAULT_CERTS,
    DEFAULT_CA,
    get_unreachable_address,
    encrypt_key_pem,
)

from .. import onlyPy3, LogRecorder

try:
    from mimetools import Message as MimeToolMessage
except ImportError:

    class MimeToolMessage(object):
        pass


from collections import OrderedDict
import os.path
from threading import Event
import os
import select
import socket
import shutil
import ssl
import tempfile
import mock

import pytest
import trustme

from test import (
    requires_ssl_context_keyfile_password,
    SHORT_TIMEOUT,
    LONG_TIMEOUT,
    notPyPy2,
    notSecureTransport,
    resolvesLocalhostFQDN,
)

# Retry failed tests
pytestmark = pytest.mark.flaky


class TestCookies(SocketDummyServerTestCase):
    def test_multi_setcookie(self):
        def multicookie_response_handler(listener):
            sock = listener.accept()[0]

            buf = b""
            while not buf.endswith(b"\r\n\r\n"):
                buf += sock.recv(65536)

            sock.send(
                b"HTTP/1.1 200 OK\r\n"
                b"Set-Cookie: foo=1\r\n"
                b"Set-Cookie: bar=1\r\n"
                b"\r\n"
            )
            sock.close()

        self._start_server(multicookie_response_handler)
        with HTTPConnectionPool(self.host, self.port) as pool:
            r = pool.request("GET", "/", retries=0)
            assert r.headers == {"set-cookie": "foo=1, bar=1"}
            assert r.headers.getlist("set-cookie") == ["foo=1", "bar=1"]


class TestSNI(SocketDummyServerTestCase):
    def test_hostname_in_first_request_packet(self):
        if not util.HAS_SNI:
            pytest.skip("SNI-support not available")
        done_receiving = Event()
        self.buf = b""

        def socket_handler(listener):
            sock = listener.accept()[0]

            self.buf = sock.recv(65536)  # We only accept one packet
            done_receiving.set()  # let the test know it can proceed
            sock.close()

        self._start_server(socket_handler)
        with HTTPSConnectionPool(self.host, self.port) as pool:
            try:
                pool.request("GET", "/", retries=0)
            except MaxRetryError:  # We are violating the protocol
                pass
            successful = done_receiving.wait(LONG_TIMEOUT)
            assert successful, "Timed out waiting for connection accept"
            assert (
                self.host.encode("ascii") in self.buf
            ), "missing hostname in SSL handshake"


class TestALPN(SocketDummyServerTestCase):
    def test_alpn_protocol_in_first_request_packet(self):
        if not util.has_alpn(util.SSLContext(util.PROTOCOL_TLS)):
            pytest.skip("ALPN-support not available")

        done_receiving = Event()
        self.buf = b""

        def socket_handler(listener):
            sock = listener.accept()[0]

            self.buf = sock.recv(65536)  # We only accept one packet
            done_receiving.set()  # let the test know it can proceed
            sock.close()

        self._start_server(socket_handler)
        with HTTPSConnectionPool(self.host, self.port) as pool:
            try:
                pool.request("GET", "/", retries=0)
            except MaxRetryError:  # We are violating the protocol
                pass
            successful = done_receiving.wait(LONG_TIMEOUT)
            assert successful, "Timed out waiting for connection accept"
            for protocol in util.ALPN_PROTOCOLS:
                assert (
                    protocol.encode("ascii") in self.buf
                ), "missing ALPN protocol in SSL handshake"


class TestClientCerts(SocketDummyServerTestCase):
    """
    Tests for client certificate support.
    """

    @classmethod
    def setup_class(cls):
        cls.tmpdir = tempfile.mkdtemp()
        ca = trustme.CA()
        cert = ca.issue_cert(u"localhost")
        encrypted_key = encrypt_key_pem(cert.private_key_pem, b"letmein")

        cls.ca_path = os.path.join(cls.tmpdir, "ca.pem")
        cls.cert_combined_path = os.path.join(cls.tmpdir, "server.combined.pem")
        cls.cert_path = os.path.join(cls.tmpdir, "server.pem")
        cls.key_path = os.path.join(cls.tmpdir, "key.pem")
        cls.password_key_path = os.path.join(cls.tmpdir, "password_key.pem")

        ca.cert_pem.write_to_path(cls.ca_path)
        cert.private_key_and_cert_chain_pem.write_to_path(cls.cert_combined_path)
        cert.cert_chain_pems[0].write_to_path(cls.cert_path)
        cert.private_key_pem.write_to_path(cls.key_path)
        encrypted_key.write_to_path(cls.password_key_path)

    def teardown_class(cls):
        shutil.rmtree(cls.tmpdir)

    def _wrap_in_ssl(self, sock):
        """
        Given a single socket, wraps it in TLS.
        """
        return ssl.wrap_socket(
            sock,
            ssl_version=ssl.PROTOCOL_SSLv23,
            cert_reqs=ssl.CERT_REQUIRED,
            ca_certs=self.ca_path,
            certfile=self.cert_path,
            keyfile=self.key_path,
            server_side=True,
        )

    def test_client_certs_two_files(self):
        """
        Having a client cert in a separate file to its associated key works
        properly.
        """
        done_receiving = Event()
        client_certs = []

        def socket_handler(listener):
            sock = listener.accept()[0]
            sock = self._wrap_in_ssl(sock)

            client_certs.append(sock.getpeercert())

            data = b""
            while not data.endswith(b"\r\n\r\n"):
                data += sock.recv(8192)

            sock.sendall(
                b"HTTP/1.1 200 OK\r\n"
                b"Server: testsocket\r\n"
                b"Connection: close\r\n"
                b"Content-Length: 6\r\n"
                b"\r\n"
                b"Valid!"
            )

            done_receiving.wait(5)
            sock.close()

        self._start_server(socket_handler)
        with HTTPSConnectionPool(
            self.host,
            self.port,
            cert_file=self.cert_path,
            key_file=self.key_path,
            cert_reqs="REQUIRED",
            ca_certs=self.ca_path,
        ) as pool:
            pool.request("GET", "/", retries=0)
            done_receiving.set()

            assert len(client_certs) == 1

    def test_client_certs_one_file(self):
        """
        Having a client cert and its associated private key in just one file
        works properly.
        """
        done_receiving = Event()
        client_certs = []

        def socket_handler(listener):
            sock = listener.accept()[0]
            sock = self._wrap_in_ssl(sock)

            client_certs.append(sock.getpeercert())

            data = b""
            while not data.endswith(b"\r\n\r\n"):
                data += sock.recv(8192)

            sock.sendall(
                b"HTTP/1.1 200 OK\r\n"
                b"Server: testsocket\r\n"
                b"Connection: close\r\n"
                b"Content-Length: 6\r\n"
                b"\r\n"
                b"Valid!"
            )

            done_receiving.wait(5)
            sock.close()

        self._start_server(socket_handler)
        with HTTPSConnectionPool(
            self.host,
            self.port,
            cert_file=self.cert_combined_path,
            cert_reqs="REQUIRED",
            ca_certs=self.ca_path,
        ) as pool:
            pool.request("GET", "/", retries=0)
            done_receiving.set()

            assert len(client_certs) == 1

    def test_missing_client_certs_raises_error(self):
        """
        Having client certs not be present causes an error.
        """
        done_receiving = Event()

        def socket_handler(listener):
            sock = listener.accept()[0]

            try:
                self._wrap_in_ssl(sock)
            except ssl.SSLError:
                pass

            done_receiving.wait(5)
            sock.close()

        self._start_server(socket_handler)
        with HTTPSConnectionPool(
            self.host, self.port, cert_reqs="REQUIRED", ca_certs=self.ca_path
        ) as pool:
            with pytest.raises(MaxRetryError):
                pool.request("GET", "/", retries=0)
                done_receiving.set()
            done_receiving.set()

    @requires_ssl_context_keyfile_password
    def test_client_cert_with_string_password(self):
        self.run_client_cert_with_password_test(u"letmein")

    @requires_ssl_context_keyfile_password
    def test_client_cert_with_bytes_password(self):
        self.run_client_cert_with_password_test(b"letmein")

    def run_client_cert_with_password_test(self, password):
        """
        Tests client certificate password functionality
        """
        done_receiving = Event()
        client_certs = []

        def socket_handler(listener):
            sock = listener.accept()[0]
            sock = self._wrap_in_ssl(sock)

            client_certs.append(sock.getpeercert())

            data = b""
            while not data.endswith(b"\r\n\r\n"):
                data += sock.recv(8192)

            sock.sendall(
                b"HTTP/1.1 200 OK\r\n"
                b"Server: testsocket\r\n"
                b"Connection: close\r\n"
                b"Content-Length: 6\r\n"
                b"\r\n"
                b"Valid!"
            )

            done_receiving.wait(5)
            sock.close()

        self._start_server(socket_handler)
        ssl_context = ssl_.SSLContext(ssl_.PROTOCOL_SSLv23)
        ssl_context.load_cert_chain(
            certfile=self.cert_path, keyfile=self.password_key_path, password=password
        )

        with HTTPSConnectionPool(
            self.host,
            self.port,
            ssl_context=ssl_context,
            cert_reqs="REQUIRED",
            ca_certs=self.ca_path,
        ) as pool:
            pool.request("GET", "/", retries=0)
            done_receiving.set()

            assert len(client_certs) == 1

    @requires_ssl_context_keyfile_password
    def test_load_keyfile_with_invalid_password(self):
        context = ssl_.SSLContext(ssl_.PROTOCOL_SSLv23)

        # Different error is raised depending on context.
        if ssl_.IS_PYOPENSSL:
            from OpenSSL.SSL import Error

            expected_error = Error
        else:
            expected_error = ssl.SSLError

        with pytest.raises(expected_error):
            context.load_cert_chain(
                certfile=self.cert_path,
                keyfile=self.password_key_path,
                password=b"letmei",
            )


class TestSocketClosing(SocketDummyServerTestCase):
    def test_recovery_when_server_closes_connection(self):
        # Does the pool work seamlessly if an open connection in the
        # connection pool gets hung up on by the server, then reaches
        # the front of the queue again?

        done_closing = Event()

        def socket_handler(listener):
            for i in 0, 1:
                sock = listener.accept()[0]

                buf = b""
                while not buf.endswith(b"\r\n\r\n"):
                    buf = sock.recv(65536)

                body = "Response %d" % i
                sock.send(
                    (
                        "HTTP/1.1 200 OK\r\n"
                        "Content-Type: text/plain\r\n"
                        "Content-Length: %d\r\n"
                        "\r\n"
                        "%s" % (len(body), body)
                    ).encode("utf-8")
                )

                sock.close()  # simulate a server timing out, closing socket
                done_closing.set()  # let the test know it can proceed

        self._start_server(socket_handler)
        with HTTPConnectionPool(self.host, self.port) as pool:
            response = pool.request("GET", "/", retries=0)
            assert response.status == 200
            assert response.data == b"Response 0"

            done_closing.wait()  # wait until the socket in our pool gets closed

            response = pool.request("GET", "/", retries=0)
            assert response.status == 200
            assert response.data == b"Response 1"

    def test_connection_refused(self):
        # Does the pool retry if there is no listener on the port?
        host, port = get_unreachable_address()
        with HTTPConnectionPool(host, port, maxsize=3, block=True) as http:
            with pytest.raises(MaxRetryError):
                http.request("GET", "/", retries=0, release_conn=False)
            assert http.pool.qsize() == http.pool.maxsize

    def test_connection_read_timeout(self):
        timed_out = Event()

        def socket_handler(listener):
            sock = listener.accept()[0]
            while not sock.recv(65536).endswith(b"\r\n\r\n"):
                pass

            timed_out.wait()
            sock.close()

        self._start_server(socket_handler)
        with HTTPConnectionPool(
            self.host,
            self.port,
            timeout=SHORT_TIMEOUT,
            retries=False,
            maxsize=3,
            block=True,
        ) as http:
            try:
                with pytest.raises(ReadTimeoutError):
                    http.request("GET", "/", release_conn=False)
            finally:
                timed_out.set()

            assert http.pool.qsize() == http.pool.maxsize

    def test_read_timeout_dont_retry_method_not_in_whitelist(self):
        timed_out = Event()

        def socket_handler(listener):
            sock = listener.accept()[0]
            sock.recv(65536)
            timed_out.wait()
            sock.close()

        self._start_server(socket_handler)
        with HTTPConnectionPool(
            self.host, self.port, timeout=SHORT_TIMEOUT, retries=True
        ) as pool:
            try:
                with pytest.raises(ReadTimeoutError):
                    pool.request("POST", "/")
            finally:
                timed_out.set()

    def test_https_connection_read_timeout(self):
        """ Handshake timeouts should fail with a Timeout"""
        timed_out = Event()

        def socket_handler(listener):
            sock = listener.accept()[0]
            while not sock.recv(65536):
                pass

            timed_out.wait()
            sock.close()

        self._start_server(socket_handler)
        with HTTPSConnectionPool(
            self.host, self.port, timeout=SHORT_TIMEOUT, retries=False
        ) as pool:
            try:
                with pytest.raises(ReadTimeoutError):
                    pool.request("GET", "/")
            finally:
                timed_out.set()

    def test_timeout_errors_cause_retries(self):
        def socket_handler(listener):
            sock_timeout = listener.accept()[0]

            # Wait for a second request before closing the first socket.
            sock = listener.accept()[0]
            sock_timeout.close()

            # Second request.
            buf = b""
            while not buf.endswith(b"\r\n\r\n"):
                buf += sock.recv(65536)

            # Now respond immediately.
            body = "Response 2"
            sock.send(
                (
                    "HTTP/1.1 200 OK\r\n"
                    "Content-Type: text/plain\r\n"
                    "Content-Length: %d\r\n"
                    "\r\n"
                    "%s" % (len(body), body)
                ).encode("utf-8")
            )

            sock.close()

        # In situations where the main thread throws an exception, the server
        # thread can hang on an accept() call. This ensures everything times
        # out within 1 second. This should be long enough for any socket
        # operations in the test suite to complete
        default_timeout = socket.getdefaulttimeout()
        socket.setdefaulttimeout(1)

        try:
            self._start_server(socket_handler)
            t = Timeout(connect=LONG_TIMEOUT, read=LONG_TIMEOUT)
            with HTTPConnectionPool(self.host, self.port, timeout=t) as pool:
                response = pool.request("GET", "/", retries=1)
                assert response.status == 200
                assert response.data == b"Response 2"
        finally:
            socket.setdefaulttimeout(default_timeout)

    def test_delayed_body_read_timeout(self):
        timed_out = Event()

        def socket_handler(listener):
            sock = listener.accept()[0]
            buf = b""
            body = "Hi"
            while not buf.endswith(b"\r\n\r\n"):
                buf = sock.recv(65536)
            sock.send(
                (
                    "HTTP/1.1 200 OK\r\n"
                    "Content-Type: text/plain\r\n"
                    "Content-Length: %d\r\n"
                    "\r\n" % len(body)
                ).encode("utf-8")
            )

            timed_out.wait()
            sock.send(body.encode("utf-8"))
            sock.close()

        self._start_server(socket_handler)
        with HTTPConnectionPool(self.host, self.port) as pool:
            response = pool.urlopen(
                "GET",
                "/",
                retries=0,
                preload_content=False,
                timeout=Timeout(connect=1, read=LONG_TIMEOUT),
            )
            try:
                with pytest.raises(ReadTimeoutError):
                    response.read()
            finally:
                timed_out.set()

    def test_delayed_body_read_timeout_with_preload(self):
        timed_out = Event()

        def socket_handler(listener):
            sock = listener.accept()[0]
            buf = b""
            body = "Hi"
            while not buf.endswith(b"\r\n\r\n"):
                buf += sock.recv(65536)
            sock.send(
                (
                    "HTTP/1.1 200 OK\r\n"
                    "Content-Type: text/plain\r\n"
                    "Content-Length: %d\r\n"
                    "\r\n" % len(body)
                ).encode("utf-8")
            )

            timed_out.wait(5)
            sock.close()

        self._start_server(socket_handler)
        with HTTPConnectionPool(self.host, self.port) as pool:
            try:
                with pytest.raises(ReadTimeoutError):
                    timeout = Timeout(connect=LONG_TIMEOUT, read=SHORT_TIMEOUT)
                    pool.urlopen("GET", "/", retries=False, timeout=timeout)
            finally:
                timed_out.set()

    def test_incomplete_response(self):
        body = "Response"
        partial_body = body[:2]

        def socket_handler(listener):
            sock = listener.accept()[0]

            # Consume request
            buf = b""
            while not buf.endswith(b"\r\n\r\n"):
                buf = sock.recv(65536)

            # Send partial response and close socket.
            sock.send(
                (
                    "HTTP/1.1 200 OK\r\n"
                    "Content-Type: text/plain\r\n"
                    "Content-Length: %d\r\n"
                    "\r\n"
                    "%s" % (len(body), partial_body)
                ).encode("utf-8")
            )
            sock.close()

        self._start_server(socket_handler)
        with HTTPConnectionPool(self.host, self.port) as pool:
            response = pool.request("GET", "/", retries=0, preload_content=False)
            with pytest.raises(ProtocolError):
                response.read()

    def test_retry_weird_http_version(self):
        """ Retry class should handle httplib.BadStatusLine errors properly """

        def socket_handler(listener):
            sock = listener.accept()[0]
            # First request.
            # Pause before responding so the first request times out.
            buf = b""
            while not buf.endswith(b"\r\n\r\n"):
                buf += sock.recv(65536)

            # send unknown http protocol
            body = "bad http 0.5 response"
            sock.send(
                (
                    "HTTP/0.5 200 OK\r\n"
                    "Content-Type: text/plain\r\n"
                    "Content-Length: %d\r\n"
                    "\r\n"
                    "%s" % (len(body), body)
                ).encode("utf-8")
            )
            sock.close()

            # Second request.
            sock = listener.accept()[0]
            buf = b""
            while not buf.endswith(b"\r\n\r\n"):
                buf += sock.recv(65536)

            # Now respond immediately.
            sock.send(
                (
                    "HTTP/1.1 200 OK\r\n"
                    "Content-Type: text/plain\r\n"
                    "Content-Length: %d\r\n"
                    "\r\n"
                    "foo" % (len("foo"))
                ).encode("utf-8")
            )

            sock.close()  # Close the socket.

        self._start_server(socket_handler)
        with HTTPConnectionPool(self.host, self.port) as pool:
            retry = Retry(read=1)
            response = pool.request("GET", "/", retries=retry)
            assert response.status == 200
            assert response.data == b"foo"

    def test_connection_cleanup_on_read_timeout(self):
        timed_out = Event()

        def socket_handler(listener):
            sock = listener.accept()[0]
            buf = b""
            body = "Hi"
            while not buf.endswith(b"\r\n\r\n"):
                buf = sock.recv(65536)
            sock.send(
                (
                    "HTTP/1.1 200 OK\r\n"
                    "Content-Type: text/plain\r\n"
                    "Content-Length: %d\r\n"
                    "\r\n" % len(body)
                ).encode("utf-8")
            )

            timed_out.wait()
            sock.close()

        self._start_server(socket_handler)
        with HTTPConnectionPool(self.host, self.port) as pool:
            poolsize = pool.pool.qsize()
            timeout = Timeout(connect=LONG_TIMEOUT, read=SHORT_TIMEOUT)
            response = pool.urlopen(
                "GET", "/", retries=0, preload_content=False, timeout=timeout
            )
            try:
                with pytest.raises(ReadTimeoutError):
                    response.read()
                assert poolsize == pool.pool.qsize()
            finally:
                timed_out.set()

    def test_connection_cleanup_on_protocol_error_during_read(self):
        body = "Response"
        partial_body = body[:2]

        def socket_handler(listener):
            sock = listener.accept()[0]

            # Consume request
            buf = b""
            while not buf.endswith(b"\r\n\r\n"):
                buf = sock.recv(65536)

            # Send partial response and close socket.
            sock.send(
                (
                    "HTTP/1.1 200 OK\r\n"
                    "Content-Type: text/plain\r\n"
                    "Content-Length: %d\r\n"
                    "\r\n"
                    "%s" % (len(body), partial_body)
                ).encode("utf-8")
            )
            sock.close()

        self._start_server(socket_handler)
        with HTTPConnectionPool(self.host, self.port) as pool:
            poolsize = pool.pool.qsize()
            response = pool.request("GET", "/", retries=0, preload_content=False)

            with pytest.raises(ProtocolError):
                response.read()
            assert poolsize == pool.pool.qsize()

    def test_connection_closed_on_read_timeout_preload_false(self):
        timed_out = Event()

        def socket_handler(listener):
            sock = listener.accept()[0]

            # Consume request
            buf = b""
            while not buf.endswith(b"\r\n\r\n"):
                buf = sock.recv(65535)

            # Send partial chunked response and then hang.
            sock.send(
                (
                    "HTTP/1.1 200 OK\r\n"
                    "Content-Type: text/plain\r\n"
                    "Transfer-Encoding: chunked\r\n"
                    "\r\n"
                    "8\r\n"
                    "12345678\r\n"
                ).encode("utf-8")
            )
            timed_out.wait(5)

            # Expect a new request, but keep hold of the old socket to avoid
            # leaking it. Because we don't want to hang this thread, we
            # actually use select.select to confirm that a new request is
            # coming in: this lets us time the thread out.
            rlist, _, _ = select.select([listener], [], [], 1)
            assert rlist
            new_sock = listener.accept()[0]

            # Consume request
            buf = b""
            while not buf.endswith(b"\r\n\r\n"):
                buf = new_sock.recv(65535)

            # Send complete chunked response.
            new_sock.send(
                (
                    "HTTP/1.1 200 OK\r\n"
                    "Content-Type: text/plain\r\n"
                    "Transfer-Encoding: chunked\r\n"
                    "\r\n"
                    "8\r\n"
                    "12345678\r\n"
                    "0\r\n\r\n"
                ).encode("utf-8")
            )

            new_sock.close()
            sock.close()

        self._start_server(socket_handler)
        with HTTPConnectionPool(self.host, self.port) as pool:
            # First request should fail.
            response = pool.urlopen(
                "GET", "/", retries=0, preload_content=False, timeout=LONG_TIMEOUT
            )
            try:
                with pytest.raises(ReadTimeoutError):
                    response.read()
            finally:
                timed_out.set()

            # Second should succeed.
            response = pool.urlopen(
                "GET", "/", retries=0, preload_content=False, timeout=LONG_TIMEOUT
            )
            assert len(response.read()) == 8

    def test_closing_response_actually_closes_connection(self):
        done_closing = Event()
        complete = Event()

        def socket_handler(listener):
            sock = listener.accept()[0]

            buf = b""
            while not buf.endswith(b"\r\n\r\n"):
                buf = sock.recv(65536)

            sock.send(
                (
                    "HTTP/1.1 200 OK\r\n"
                    "Content-Type: text/plain\r\n"
                    "Content-Length: 0\r\n"
                    "\r\n"
                ).encode("utf-8")
            )

            # Wait for the socket to close.
            done_closing.wait(timeout=LONG_TIMEOUT)

            # Look for the empty string to show that the connection got closed.
            # Don't get stuck in a timeout.
            sock.settimeout(LONG_TIMEOUT)
            new_data = sock.recv(65536)
            assert not new_data
            sock.close()
            complete.set()

        self._start_server(socket_handler)
        with HTTPConnectionPool(self.host, self.port) as pool:
            response = pool.request("GET", "/", retries=0, preload_content=False)
            assert response.status == 200
            response.close()

            done_closing.set()  # wait until the socket in our pool gets closed
            successful = complete.wait(timeout=LONG_TIMEOUT)
            assert successful, "Timed out waiting for connection close"

    def test_release_conn_param_is_respected_after_timeout_retry(self):
        """For successful ```urlopen(release_conn=False)```,
        the connection isn't released, even after a retry.

        This test allows a retry: one request fails, the next request succeeds.

        This is a regression test for issue #651 [1], where the connection
        would be released if the initial request failed, even if a retry
        succeeded.

        [1] <https://github.com/urllib3/urllib3/issues/651>
        """

        def socket_handler(listener):
            sock = listener.accept()[0]
            consume_socket(sock)

            # Close the connection, without sending any response (not even the
            # HTTP status line). This will trigger a `Timeout` on the client,
            # inside `urlopen()`.
            sock.close()

            # Expect a new request. Because we don't want to hang this thread,
            # we actually use select.select to confirm that a new request is
            # coming in: this lets us time the thread out.
            rlist, _, _ = select.select([listener], [], [], 5)
            assert rlist
            sock = listener.accept()[0]
            consume_socket(sock)

            # Send complete chunked response.
            sock.send(
                (
                    "HTTP/1.1 200 OK\r\n"
                    "Content-Type: text/plain\r\n"
                    "Transfer-Encoding: chunked\r\n"
                    "\r\n"
                    "8\r\n"
                    "12345678\r\n"
                    "0\r\n\r\n"
                ).encode("utf-8")
            )

            sock.close()

        self._start_server(socket_handler)
        with HTTPConnectionPool(self.host, self.port, maxsize=1) as pool:
            # First request should fail, but the timeout and `retries=1` should
            # save it.
            response = pool.urlopen(
                "GET",
                "/",
                retries=1,
                release_conn=False,
                preload_content=False,
                timeout=Timeout(connect=LONG_TIMEOUT, read=SHORT_TIMEOUT),
            )

            # The connection should still be on the response object, and none
            # should be in the pool. We opened two though.
            assert pool.num_connections == 2
            assert pool.pool.qsize() == 0
            assert response.connection is not None

            # Consume the data. This should put the connection back.
            response.read()
            assert pool.pool.qsize() == 1
            assert response.connection is None


class TestProxyManager(SocketDummyServerTestCase):
    def test_simple(self):
        def echo_socket_handler(listener):
            sock = listener.accept()[0]

            buf = b""
            while not buf.endswith(b"\r\n\r\n"):
                buf += sock.recv(65536)

            sock.send(
                (
                    "HTTP/1.1 200 OK\r\n"
                    "Content-Type: text/plain\r\n"
                    "Content-Length: %d\r\n"
                    "\r\n"
                    "%s" % (len(buf), buf.decode("utf-8"))
                ).encode("utf-8")
            )
            sock.close()

        self._start_server(echo_socket_handler)
        base_url = "http://%s:%d" % (self.host, self.port)
        with proxy_from_url(base_url) as proxy:
            r = proxy.request("GET", "http://google.com/")

            assert r.status == 200
            # FIXME: The order of the headers is not predictable right now. We
            # should fix that someday (maybe when we migrate to
            # OrderedDict/MultiDict).
            assert sorted(r.data.split(b"\r\n")) == sorted(
                [
                    b"GET http://google.com/ HTTP/1.1",
                    b"Host: google.com",
                    b"Accept-Encoding: identity",
                    b"Accept: */*",
                    b"",
                    b"",
                ]
            )

    def test_headers(self):
        def echo_socket_handler(listener):
            sock = listener.accept()[0]

            buf = b""
            while not buf.endswith(b"\r\n\r\n"):
                buf += sock.recv(65536)

            sock.send(
                (
                    "HTTP/1.1 200 OK\r\n"
                    "Content-Type: text/plain\r\n"
                    "Content-Length: %d\r\n"
                    "\r\n"
                    "%s" % (len(buf), buf.decode("utf-8"))
                ).encode("utf-8")
            )
            sock.close()

        self._start_server(echo_socket_handler)
        base_url = "http://%s:%d" % (self.host, self.port)

        # Define some proxy headers.
        proxy_headers = HTTPHeaderDict({"For The Proxy": "YEAH!"})
        with proxy_from_url(base_url, proxy_headers=proxy_headers) as proxy:
            conn = proxy.connection_from_url("http://www.google.com/")

            r = conn.urlopen("GET", "http://www.google.com/", assert_same_host=False)

            assert r.status == 200
            # FIXME: The order of the headers is not predictable right now. We
            # should fix that someday (maybe when we migrate to
            # OrderedDict/MultiDict).
            assert b"For The Proxy: YEAH!\r\n" in r.data

    def test_retries(self):
        close_event = Event()

        def echo_socket_handler(listener):
            sock = listener.accept()[0]
            # First request, which should fail
            sock.close()

            # Second request
            sock = listener.accept()[0]

            buf = b""
            while not buf.endswith(b"\r\n\r\n"):
                buf += sock.recv(65536)

            sock.send(
                (
                    "HTTP/1.1 200 OK\r\n"
                    "Content-Type: text/plain\r\n"
                    "Content-Length: %d\r\n"
                    "\r\n"
                    "%s" % (len(buf), buf.decode("utf-8"))
                ).encode("utf-8")
            )
            sock.close()
            close_event.set()

        self._start_server(echo_socket_handler)
        base_url = "http://%s:%d" % (self.host, self.port)

        with proxy_from_url(base_url) as proxy:
            conn = proxy.connection_from_url("http://www.google.com")

            r = conn.urlopen(
                "GET", "http://www.google.com", assert_same_host=False, retries=1
            )
            assert r.status == 200

            close_event.wait(timeout=LONG_TIMEOUT)
            with pytest.raises(ProxyError):
                conn.urlopen(
                    "GET",
                    "http://www.google.com",
                    assert_same_host=False,
                    retries=False,
                )

    def test_connect_reconn(self):
        def proxy_ssl_one(listener):
            sock = listener.accept()[0]

            buf = b""
            while not buf.endswith(b"\r\n\r\n"):
                buf += sock.recv(65536)
            s = buf.decode("utf-8")
            if not s.startswith("CONNECT "):
                sock.send(
                    (
                        "HTTP/1.1 405 Method not allowed\r\nAllow: CONNECT\r\n\r\n"
                    ).encode("utf-8")
                )
                sock.close()
                return

            if not s.startswith("CONNECT %s:443" % (self.host,)):
                sock.send(("HTTP/1.1 403 Forbidden\r\n\r\n").encode("utf-8"))
                sock.close()
                return

            sock.send(("HTTP/1.1 200 Connection Established\r\n\r\n").encode("utf-8"))
            ssl_sock = ssl.wrap_socket(
                sock,
                server_side=True,
                keyfile=DEFAULT_CERTS["keyfile"],
                certfile=DEFAULT_CERTS["certfile"],
                ca_certs=DEFAULT_CA,
            )

            buf = b""
            while not buf.endswith(b"\r\n\r\n"):
                buf += ssl_sock.recv(65536)

            ssl_sock.send(
                (
                    "HTTP/1.1 200 OK\r\n"
                    "Content-Type: text/plain\r\n"
                    "Content-Length: 2\r\n"
                    "Connection: close\r\n"
                    "\r\n"
                    "Hi"
                ).encode("utf-8")
            )
            ssl_sock.close()

        def echo_socket_handler(listener):
            proxy_ssl_one(listener)
            proxy_ssl_one(listener)

        self._start_server(echo_socket_handler)
        base_url = "http://%s:%d" % (self.host, self.port)

        with proxy_from_url(base_url, ca_certs=DEFAULT_CA) as proxy:
            url = "https://{0}".format(self.host)
            conn = proxy.connection_from_url(url)
            r = conn.urlopen("GET", url, retries=0)
            assert r.status == 200
            r = conn.urlopen("GET", url, retries=0)
            assert r.status == 200

    def test_connect_ipv6_addr(self):
        ipv6_addr = "2001:4998:c:a06::2:4008"

        def echo_socket_handler(listener):
            sock = listener.accept()[0]

            buf = b""
            while not buf.endswith(b"\r\n\r\n"):
                buf += sock.recv(65536)
            s = buf.decode("utf-8")

            if s.startswith("CONNECT [%s]:443" % (ipv6_addr,)):
                sock.send(b"HTTP/1.1 200 Connection Established\r\n\r\n")
                ssl_sock = ssl.wrap_socket(
                    sock,
                    server_side=True,
                    keyfile=DEFAULT_CERTS["keyfile"],
                    certfile=DEFAULT_CERTS["certfile"],
                )
                buf = b""
                while not buf.endswith(b"\r\n\r\n"):
                    buf += ssl_sock.recv(65536)

                ssl_sock.send(
                    b"HTTP/1.1 200 OK\r\n"
                    b"Content-Type: text/plain\r\n"
                    b"Content-Length: 2\r\n"
                    b"Connection: close\r\n"
                    b"\r\n"
                    b"Hi"
                )
                ssl_sock.close()
            else:
                sock.close()

        self._start_server(echo_socket_handler)
        base_url = "http://%s:%d" % (self.host, self.port)

        with proxy_from_url(base_url, cert_reqs="NONE") as proxy:
            url = "https://[{0}]".format(ipv6_addr)
            conn = proxy.connection_from_url(url)
            try:
                r = conn.urlopen("GET", url, retries=0)
                assert r.status == 200
            except MaxRetryError:
                self.fail("Invalid IPv6 format in HTTP CONNECT request")


class TestSSL(SocketDummyServerTestCase):
    def test_ssl_failure_midway_through_conn(self):
        def socket_handler(listener):
            sock = listener.accept()[0]
            sock2 = sock.dup()
            ssl_sock = ssl.wrap_socket(
                sock,
                server_side=True,
                keyfile=DEFAULT_CERTS["keyfile"],
                certfile=DEFAULT_CERTS["certfile"],
                ca_certs=DEFAULT_CA,
            )

            buf = b""
            while not buf.endswith(b"\r\n\r\n"):
                buf += ssl_sock.recv(65536)

            # Deliberately send from the non-SSL socket.
            sock2.send(
                (
                    "HTTP/1.1 200 OK\r\n"
                    "Content-Type: text/plain\r\n"
                    "Content-Length: 2\r\n"
                    "\r\n"
                    "Hi"
                ).encode("utf-8")
            )
            sock2.close()
            ssl_sock.close()

        self._start_server(socket_handler)
        with HTTPSConnectionPool(self.host, self.port) as pool:
            with pytest.raises(MaxRetryError) as cm:
                pool.request("GET", "/", retries=0)
            assert isinstance(cm.value.reason, SSLError)

    @notSecureTransport
    def test_ssl_read_timeout(self):
        timed_out = Event()

        def socket_handler(listener):
            sock = listener.accept()[0]
            ssl_sock = ssl.wrap_socket(
                sock,
                server_side=True,
                keyfile=DEFAULT_CERTS["keyfile"],
                certfile=DEFAULT_CERTS["certfile"],
            )

            buf = b""
            while not buf.endswith(b"\r\n\r\n"):
                buf += ssl_sock.recv(65536)

            # Send incomplete message (note Content-Length)
            ssl_sock.send(
                (
                    "HTTP/1.1 200 OK\r\n"
                    "Content-Type: text/plain\r\n"
                    "Content-Length: 10\r\n"
                    "\r\n"
                    "Hi-"
                ).encode("utf-8")
            )
            timed_out.wait()

            sock.close()
            ssl_sock.close()

        self._start_server(socket_handler)
        with HTTPSConnectionPool(self.host, self.port, ca_certs=DEFAULT_CA) as pool:
            response = pool.urlopen(
                "GET", "/", retries=0, preload_content=False, timeout=LONG_TIMEOUT
            )
            try:
                with pytest.raises(ReadTimeoutError):
                    response.read()
            finally:
                timed_out.set()

    def test_ssl_failed_fingerprint_verification(self):
        def socket_handler(listener):
            for i in range(2):
                sock = listener.accept()[0]
                ssl_sock = ssl.wrap_socket(
                    sock,
                    server_side=True,
                    keyfile=DEFAULT_CERTS["keyfile"],
                    certfile=DEFAULT_CERTS["certfile"],
                    ca_certs=DEFAULT_CA,
                )

                ssl_sock.send(
                    b"HTTP/1.1 200 OK\r\n"
                    b"Content-Type: text/plain\r\n"
                    b"Content-Length: 5\r\n\r\n"
                    b"Hello"
                )

                ssl_sock.close()
                sock.close()

        self._start_server(socket_handler)
        # GitHub's fingerprint. Valid, but not matching.
        fingerprint = "A0:C4:A7:46:00:ED:A7:2D:C0:BE:CB:9A:8C:B6:07:CA:58:EE:74:5E"

        def request():
            pool = HTTPSConnectionPool(
                self.host, self.port, assert_fingerprint=fingerprint
            )
            try:
                timeout = Timeout(connect=LONG_TIMEOUT, read=SHORT_TIMEOUT)
                response = pool.urlopen(
                    "GET", "/", preload_content=False, retries=0, timeout=timeout
                )
                response.read()
            finally:
                pool.close()

        with pytest.raises(MaxRetryError) as cm:
            request()
        assert isinstance(cm.value.reason, SSLError)
        # Should not hang, see https://github.com/urllib3/urllib3/issues/529
        with pytest.raises(MaxRetryError):
            request()

    def test_retry_ssl_error(self):
        def socket_handler(listener):
            # first request, trigger an SSLError
            sock = listener.accept()[0]
            sock2 = sock.dup()
            ssl_sock = ssl.wrap_socket(
                sock,
                server_side=True,
                keyfile=DEFAULT_CERTS["keyfile"],
                certfile=DEFAULT_CERTS["certfile"],
            )
            buf = b""
            while not buf.endswith(b"\r\n\r\n"):
                buf += ssl_sock.recv(65536)

            # Deliberately send from the non-SSL socket to trigger an SSLError
            sock2.send(
                (
                    "HTTP/1.1 200 OK\r\n"
                    "Content-Type: text/plain\r\n"
                    "Content-Length: 4\r\n"
                    "\r\n"
                    "Fail"
                ).encode("utf-8")
            )
            sock2.close()
            ssl_sock.close()

            # retried request
            sock = listener.accept()[0]
            ssl_sock = ssl.wrap_socket(
                sock,
                server_side=True,
                keyfile=DEFAULT_CERTS["keyfile"],
                certfile=DEFAULT_CERTS["certfile"],
            )
            buf = b""
            while not buf.endswith(b"\r\n\r\n"):
                buf += ssl_sock.recv(65536)
            ssl_sock.send(
                b"HTTP/1.1 200 OK\r\n"
                b"Content-Type: text/plain\r\n"
                b"Content-Length: 7\r\n\r\n"
                b"Success"
            )
            ssl_sock.close()

        self._start_server(socket_handler)

        with HTTPSConnectionPool(self.host, self.port, ca_certs=DEFAULT_CA) as pool:
            response = pool.urlopen("GET", "/", retries=1)
            assert response.data == b"Success"

    def test_ssl_load_default_certs_when_empty(self):
        def socket_handler(listener):
            sock = listener.accept()[0]
            ssl_sock = ssl.wrap_socket(
                sock,
                server_side=True,
                keyfile=DEFAULT_CERTS["keyfile"],
                certfile=DEFAULT_CERTS["certfile"],
                ca_certs=DEFAULT_CA,
            )

            buf = b""
            while not buf.endswith(b"\r\n\r\n"):
                buf += ssl_sock.recv(65536)

            ssl_sock.send(
                b"HTTP/1.1 200 OK\r\n"
                b"Content-Type: text/plain\r\n"
                b"Content-Length: 5\r\n\r\n"
                b"Hello"
            )

            ssl_sock.close()
            sock.close()

        context = mock.create_autospec(ssl_.SSLContext)
        context.load_default_certs = mock.Mock()
        context.options = 0

        with mock.patch("urllib3.util.ssl_.SSLContext", lambda *_, **__: context):
            self._start_server(socket_handler)
            with HTTPSConnectionPool(self.host, self.port) as pool:
                with pytest.raises(MaxRetryError):
                    pool.request("GET", "/", timeout=SHORT_TIMEOUT)
                context.load_default_certs.assert_called_with()

    @notPyPy2
    def test_ssl_dont_load_default_certs_when_given(self):
        def socket_handler(listener):
            sock = listener.accept()[0]
            ssl_sock = ssl.wrap_socket(
                sock,
                server_side=True,
                keyfile=DEFAULT_CERTS["keyfile"],
                certfile=DEFAULT_CERTS["certfile"],
                ca_certs=DEFAULT_CA,
            )

            buf = b""
            while not buf.endswith(b"\r\n\r\n"):
                buf += ssl_sock.recv(65536)

            ssl_sock.send(
                b"HTTP/1.1 200 OK\r\n"
                b"Content-Type: text/plain\r\n"
                b"Content-Length: 5\r\n\r\n"
                b"Hello"
            )

            ssl_sock.close()
            sock.close()

        context = mock.create_autospec(ssl_.SSLContext)
        context.load_default_certs = mock.Mock()
        context.options = 0

        with mock.patch("urllib3.util.ssl_.SSLContext", lambda *_, **__: context):
            for kwargs in [
                {"ca_certs": "/a"},
                {"ca_cert_dir": "/a"},
                {"ca_certs": "a", "ca_cert_dir": "a"},
                {"ssl_context": context},
            ]:

                self._start_server(socket_handler)

                with HTTPSConnectionPool(self.host, self.port, **kwargs) as pool:
                    with pytest.raises(MaxRetryError):
                        pool.request("GET", "/", timeout=SHORT_TIMEOUT)
                    context.load_default_certs.assert_not_called()

    def test_load_verify_locations_exception(self):
        """
        Ensure that load_verify_locations raises SSLError for all backends
        """
        with pytest.raises(SSLError):
            ssl_wrap_socket(None, ca_certs="/tmp/fake-file")


class TestErrorWrapping(SocketDummyServerTestCase):
    def test_bad_statusline(self):
        self.start_response_handler(
            b"HTTP/1.1 Omg What Is This?\r\n" b"Content-Length: 0\r\n" b"\r\n"
        )
        with HTTPConnectionPool(self.host, self.port, retries=False) as pool:
            with pytest.raises(ProtocolError):
                pool.request("GET", "/")

    def test_unknown_protocol(self):
        self.start_response_handler(
            b"HTTP/1000 200 OK\r\n" b"Content-Length: 0\r\n" b"\r\n"
        )
        with HTTPConnectionPool(self.host, self.port, retries=False) as pool:
            with pytest.raises(ProtocolError):
                pool.request("GET", "/")


class TestHeaders(SocketDummyServerTestCase):
    @onlyPy3
    def test_httplib_headers_case_insensitive(self):
        self.start_response_handler(
            b"HTTP/1.1 200 OK\r\n"
            b"Content-Length: 0\r\n"
            b"Content-type: text/plain\r\n"
            b"\r\n"
        )
        with HTTPConnectionPool(self.host, self.port, retries=False) as pool:
            HEADERS = {"Content-Length": "0", "Content-type": "text/plain"}
            r = pool.request("GET", "/")
            assert HEADERS == dict(r.headers.items())  # to preserve case sensitivity

    def test_headers_are_sent_with_the_original_case(self):
        headers = {"foo": "bar", "bAz": "quux"}
        parsed_headers = {}

        def socket_handler(listener):
            sock = listener.accept()[0]

            buf = b""
            while not buf.endswith(b"\r\n\r\n"):
                buf += sock.recv(65536)

            headers_list = [header for header in buf.split(b"\r\n")[1:] if header]

            for header in headers_list:
                (key, value) = header.split(b": ")
                parsed_headers[key.decode("ascii")] = value.decode("ascii")

            sock.send(
                ("HTTP/1.1 204 No Content\r\nContent-Length: 0\r\n\r\n").encode("utf-8")
            )

            sock.close()

        self._start_server(socket_handler)
        expected_headers = {
            "Accept-Encoding": "identity",
            "Host": "{0}:{1}".format(self.host, self.port),
        }
        expected_headers.update(headers)

        with HTTPConnectionPool(self.host, self.port, retries=False) as pool:
            pool.request("GET", "/", headers=HTTPHeaderDict(headers))
            assert expected_headers == parsed_headers

    def test_request_headers_are_sent_in_the_original_order(self):
        # NOTE: Probability this test gives a false negative is 1/(K!)
        K = 16
        # NOTE: Provide headers in non-sorted order (i.e. reversed)
        #       so that if the internal implementation tries to sort them,
        #       a change will be detected.
        expected_request_headers = [
            (u"X-Header-%d" % i, str(i)) for i in reversed(range(K))
        ]

        actual_request_headers = []

        def socket_handler(listener):
            sock = listener.accept()[0]

            buf = b""
            while not buf.endswith(b"\r\n\r\n"):
                buf += sock.recv(65536)

            headers_list = [header for header in buf.split(b"\r\n")[1:] if header]

            for header in headers_list:
                (key, value) = header.split(b": ")
                if not key.decode("ascii").startswith(u"X-Header-"):
                    continue
                actual_request_headers.append(
                    (key.decode("ascii"), value.decode("ascii"))
                )

            sock.send(
                (u"HTTP/1.1 204 No Content\r\nContent-Length: 0\r\n\r\n").encode(
                    "ascii"
                )
            )

            sock.close()

        self._start_server(socket_handler)

        with HTTPConnectionPool(self.host, self.port, retries=False) as pool:
            pool.request("GET", "/", headers=OrderedDict(expected_request_headers))
            assert expected_request_headers == actual_request_headers

    @resolvesLocalhostFQDN
    def test_request_host_header_ignores_fqdn_dot(self):

        received_headers = []

        def socket_handler(listener):
            sock = listener.accept()[0]

            buf = b""
            while not buf.endswith(b"\r\n\r\n"):
                buf += sock.recv(65536)

            for header in buf.split(b"\r\n")[1:]:
                if header:
                    received_headers.append(header)

            sock.send(
                (u"HTTP/1.1 204 No Content\r\nContent-Length: 0\r\n\r\n").encode(
                    "ascii"
                )
            )

            sock.close()

        self._start_server(socket_handler)

        with HTTPConnectionPool(self.host + ".", self.port, retries=False) as pool:
            pool.request("GET", "/")
            self.assert_header_received(
                received_headers, "Host", "%s:%s" % (self.host, self.port)
            )

    def test_response_headers_are_returned_in_the_original_order(self):
        # NOTE: Probability this test gives a false negative is 1/(K!)
        K = 16
        # NOTE: Provide headers in non-sorted order (i.e. reversed)
        #       so that if the internal implementation tries to sort them,
        #       a change will be detected.
        expected_response_headers = [
            ("X-Header-%d" % i, str(i)) for i in reversed(range(K))
        ]

        def socket_handler(listener):
            sock = listener.accept()[0]

            buf = b""
            while not buf.endswith(b"\r\n\r\n"):
                buf += sock.recv(65536)

            sock.send(
                b"HTTP/1.1 200 OK\r\n"
                + b"\r\n".join(
                    [
                        (k.encode("utf8") + b": " + v.encode("utf8"))
                        for (k, v) in expected_response_headers
                    ]
                )
                + b"\r\n"
            )
            sock.close()

        self._start_server(socket_handler)
        with HTTPConnectionPool(self.host, self.port) as pool:
            r = pool.request("GET", "/", retries=0)
            actual_response_headers = [
                (k, v) for (k, v) in r.headers.items() if k.startswith("X-Header-")
            ]
            assert expected_response_headers == actual_response_headers


@pytest.mark.skipif(
    issubclass(httplib.HTTPMessage, MimeToolMessage),
    reason="Header parsing errors not available",
)
class TestBrokenHeaders(SocketDummyServerTestCase):
    def _test_broken_header_parsing(self, headers, unparsed_data_check=None):
        self.start_response_handler(
            (
                b"HTTP/1.1 200 OK\r\n"
                b"Content-Length: 0\r\n"
                b"Content-type: text/plain\r\n"
            )
            + b"\r\n".join(headers)
            + b"\r\n\r\n"
        )

        with HTTPConnectionPool(self.host, self.port, retries=False) as pool:
            with LogRecorder() as logs:
                pool.request("GET", "/")

            for record in logs:
                if (
                    "Failed to parse headers" in record.msg
                    and pool._absolute_url("/") == record.args[0]
                ):
                    if (
                        unparsed_data_check is None
                        or unparsed_data_check in record.getMessage()
                    ):
                        return
            self.fail("Missing log about unparsed headers")

    def test_header_without_name(self):
        self._test_broken_header_parsing([b": Value", b"Another: Header"])

    def test_header_without_name_or_value(self):
        self._test_broken_header_parsing([b":", b"Another: Header"])

    def test_header_without_colon_or_value(self):
        self._test_broken_header_parsing(
            [b"Broken Header", b"Another: Header"], "Broken Header"
        )


class TestHeaderParsingContentType(SocketDummyServerTestCase):
    def _test_okay_header_parsing(self, header):
        self.start_response_handler(
            (b"HTTP/1.1 200 OK\r\n" b"Content-Length: 0\r\n") + header + b"\r\n\r\n"
        )

        with HTTPConnectionPool(self.host, self.port, retries=False) as pool:
            with LogRecorder() as logs:
                pool.request("GET", "/")

            for record in logs:
                assert "Failed to parse headers" not in record.msg

    def test_header_text_plain(self):
        self._test_okay_header_parsing(b"Content-type: text/plain")

    def test_header_message_rfc822(self):
        self._test_okay_header_parsing(b"Content-type: message/rfc822")


class TestHEAD(SocketDummyServerTestCase):
    def test_chunked_head_response_does_not_hang(self):
        self.start_response_handler(
            b"HTTP/1.1 200 OK\r\n"
            b"Transfer-Encoding: chunked\r\n"
            b"Content-type: text/plain\r\n"
            b"\r\n"
        )
        with HTTPConnectionPool(self.host, self.port, retries=False) as pool:
            r = pool.request("HEAD", "/", timeout=LONG_TIMEOUT, preload_content=False)

            # stream will use the read_chunked method here.
            assert [] == list(r.stream())

    def test_empty_head_response_does_not_hang(self):
        self.start_response_handler(
            b"HTTP/1.1 200 OK\r\n"
            b"Content-Length: 256\r\n"
            b"Content-type: text/plain\r\n"
            b"\r\n"
        )
        with HTTPConnectionPool(self.host, self.port, retries=False) as pool:
            r = pool.request("HEAD", "/", timeout=LONG_TIMEOUT, preload_content=False)

            # stream will use the read method here.
            assert [] == list(r.stream())


class TestStream(SocketDummyServerTestCase):
    def test_stream_none_unchunked_response_does_not_hang(self):
        done_event = Event()

        def socket_handler(listener):
            sock = listener.accept()[0]

            buf = b""
            while not buf.endswith(b"\r\n\r\n"):
                buf += sock.recv(65536)

            sock.send(
                b"HTTP/1.1 200 OK\r\n"
                b"Content-Length: 12\r\n"
                b"Content-type: text/plain\r\n"
                b"\r\n"
                b"hello, world"
            )
            done_event.wait(5)
            sock.close()

        self._start_server(socket_handler)
        with HTTPConnectionPool(self.host, self.port, retries=False) as pool:
            r = pool.request("GET", "/", timeout=LONG_TIMEOUT, preload_content=False)

            # Stream should read to the end.
            assert [b"hello, world"] == list(r.stream(None))

            done_event.set()


class TestBadContentLength(SocketDummyServerTestCase):
    def test_enforce_content_length_get(self):
        done_event = Event()

        def socket_handler(listener):
            sock = listener.accept()[0]

            buf = b""
            while not buf.endswith(b"\r\n\r\n"):
                buf += sock.recv(65536)

            sock.send(
                b"HTTP/1.1 200 OK\r\n"
                b"Content-Length: 22\r\n"
                b"Content-type: text/plain\r\n"
                b"\r\n"
                b"hello, world"
            )
            done_event.wait(LONG_TIMEOUT)
            sock.close()

        self._start_server(socket_handler)
        with HTTPConnectionPool(self.host, self.port, maxsize=1) as conn:
            # Test stream read when content length less than headers claim
            get_response = conn.request(
                "GET", url="/", preload_content=False, enforce_content_length=True
            )
            data = get_response.stream(100)
            # Read "good" data before we try to read again.
            # This won't trigger till generator is exhausted.
            next(data)
            try:
                next(data)
                assert False
            except ProtocolError as e:
                assert "12 bytes read, 10 more expected" in str(e)

            done_event.set()

    def test_enforce_content_length_no_body(self):
        done_event = Event()

        def socket_handler(listener):
            sock = listener.accept()[0]

            buf = b""
            while not buf.endswith(b"\r\n\r\n"):
                buf += sock.recv(65536)

            sock.send(
                b"HTTP/1.1 200 OK\r\n"
                b"Content-Length: 22\r\n"
                b"Content-type: text/plain\r\n"
                b"\r\n"
            )
            done_event.wait(1)
            sock.close()

        self._start_server(socket_handler)
        with HTTPConnectionPool(self.host, self.port, maxsize=1) as conn:
            # Test stream on 0 length body
            head_response = conn.request(
                "HEAD", url="/", preload_content=False, enforce_content_length=True
            )
            data = [chunk for chunk in head_response.stream(1)]
            assert len(data) == 0

            done_event.set()


class TestRetryPoolSizeDrainFail(SocketDummyServerTestCase):
    def test_pool_size_retry_drain_fail(self):
        def socket_handler(listener):
            for _ in range(2):
                sock = listener.accept()[0]
                while not sock.recv(65536).endswith(b"\r\n\r\n"):
                    pass

                # send a response with an invalid content length -- this causes
                # a ProtocolError to raise when trying to drain the connection
                sock.send(
                    b"HTTP/1.1 404 NOT FOUND\r\n"
                    b"Content-Length: 1000\r\n"
                    b"Content-Type: text/plain\r\n"
                    b"\r\n"
                )
                sock.close()

        self._start_server(socket_handler)
        retries = Retry(total=1, raise_on_status=False, status_forcelist=[404])
        with HTTPConnectionPool(
            self.host, self.port, maxsize=10, retries=retries, block=True
        ) as pool:
            pool.urlopen("GET", "/not_found", preload_content=False)
            assert pool.num_connections == 1