Uploaded Test files

venv/Lib/site-packages/tornado/platform/twisted.py

@@ -0,0 +1,146 @@
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+"""Bridges between the Twisted package and Tornado.
+"""
+
+import socket
+import sys
+
+import twisted.internet.abstract  # type: ignore
+import twisted.internet.asyncioreactor  # type: ignore
+from twisted.internet.defer import Deferred  # type: ignore
+from twisted.python import failure  # type: ignore
+import twisted.names.cache  # type: ignore
+import twisted.names.client  # type: ignore
+import twisted.names.hosts  # type: ignore
+import twisted.names.resolve  # type: ignore
+
+
+from tornado.concurrent import Future, future_set_exc_info
+from tornado.escape import utf8
+from tornado import gen
+from tornado.netutil import Resolver
+
+import typing
+
+if typing.TYPE_CHECKING:
+    from typing import Generator, Any, List, Tuple  # noqa: F401
+
+
+class TwistedResolver(Resolver):
+    """Twisted-based asynchronous resolver.
+
+    This is a non-blocking and non-threaded resolver.  It is
+    recommended only when threads cannot be used, since it has
+    limitations compared to the standard ``getaddrinfo``-based
+    `~tornado.netutil.Resolver` and
+    `~tornado.netutil.DefaultExecutorResolver`.  Specifically, it returns at
+    most one result, and arguments other than ``host`` and ``family``
+    are ignored.  It may fail to resolve when ``family`` is not
+    ``socket.AF_UNSPEC``.
+
+    Requires Twisted 12.1 or newer.
+
+    .. versionchanged:: 5.0
+       The ``io_loop`` argument (deprecated since version 4.1) has been removed.
+    """
+
+    def initialize(self) -> None:
+        # partial copy of twisted.names.client.createResolver, which doesn't
+        # allow for a reactor to be passed in.
+        self.reactor = twisted.internet.asyncioreactor.AsyncioSelectorReactor()
+
+        host_resolver = twisted.names.hosts.Resolver("/etc/hosts")
+        cache_resolver = twisted.names.cache.CacheResolver(reactor=self.reactor)
+        real_resolver = twisted.names.client.Resolver(
+            "/etc/resolv.conf", reactor=self.reactor
+        )
+        self.resolver = twisted.names.resolve.ResolverChain(
+            [host_resolver, cache_resolver, real_resolver]
+        )
+
+    @gen.coroutine
+    def resolve(
+        self, host: str, port: int, family: int = 0
+    ) -> "Generator[Any, Any, List[Tuple[int, Any]]]":
+        # getHostByName doesn't accept IP addresses, so if the input
+        # looks like an IP address just return it immediately.
+        if twisted.internet.abstract.isIPAddress(host):
+            resolved = host
+            resolved_family = socket.AF_INET
+        elif twisted.internet.abstract.isIPv6Address(host):
+            resolved = host
+            resolved_family = socket.AF_INET6
+        else:
+            deferred = self.resolver.getHostByName(utf8(host))
+            fut = Future()  # type: Future[Any]
+            deferred.addBoth(fut.set_result)
+            resolved = yield fut
+            if isinstance(resolved, failure.Failure):
+                try:
+                    resolved.raiseException()
+                except twisted.names.error.DomainError as e:
+                    raise IOError(e)
+            elif twisted.internet.abstract.isIPAddress(resolved):
+                resolved_family = socket.AF_INET
+            elif twisted.internet.abstract.isIPv6Address(resolved):
+                resolved_family = socket.AF_INET6
+            else:
+                resolved_family = socket.AF_UNSPEC
+        if family != socket.AF_UNSPEC and family != resolved_family:
+            raise Exception(
+                "Requested socket family %d but got %d" % (family, resolved_family)
+            )
+        result = [(typing.cast(int, resolved_family), (resolved, port))]
+        return result
+
+
+def install() -> None:
+    """Install ``AsyncioSelectorReactor`` as the default Twisted reactor.
+
+    .. deprecated:: 5.1
+
+       This function is provided for backwards compatibility; code
+       that does not require compatibility with older versions of
+       Tornado should use
+       ``twisted.internet.asyncioreactor.install()`` directly.
+
+    .. versionchanged:: 6.0.3
+
+       In Tornado 5.x and before, this function installed a reactor
+       based on the Tornado ``IOLoop``. When that reactor
+       implementation was removed in Tornado 6.0.0, this function was
+       removed as well. It was restored in Tornado 6.0.3 using the
+       ``asyncio`` reactor instead.
+
+    """
+    from twisted.internet.asyncioreactor import install
+
+    install()
+
+
+if hasattr(gen.convert_yielded, "register"):
+
+    @gen.convert_yielded.register(Deferred)  # type: ignore
+    def _(d: Deferred) -> Future:
+        f = Future()  # type: Future[Any]
+
+        def errback(failure: failure.Failure) -> None:
+            try:
+                failure.raiseException()
+                # Should never happen, but just in case
+                raise Exception("errback called without error")
+            except:
+                future_set_exc_info(f, sys.exc_info())
+
+        d.addCallbacks(f.set_result, errback)
+        return f