Move already_listening to plugins.util

docs/api/plugins/util.rst

@@ -0,0 +1,5 @@
+:mod:`letsencrypt.plugins.util`
+-------------------------------
+
+.. automodule:: letsencrypt.plugins.util
+   :members:

letsencrypt/plugins/standalone/authenticator.py

@@ -1,6 +1,5 @@
 """Standalone authenticator."""
 import os
-import psutil
 import signal
 import socket
 import sys
@@ -289,47 +288,6 @@ class StandaloneAuthenticator(common.Plugin):
             # should terminate via sys.exit().
             return self.do_child_process(port)
 
-    def already_listening(self, port):  # pylint: disable=no-self-use
-        """Check if a process is already listening on the port.
-
-        If so, also tell the user via a display notification.
-
-        .. warning::
-            On some operating systems, this function can only usefully be
-            run as root.
-
-        :param int port: The TCP port in question.
-        :returns: True or False."""
-
-        listeners = [conn.pid for conn in psutil.net_connections()
-                     if conn.status == 'LISTEN' and
-                     conn.type == socket.SOCK_STREAM and
-                     conn.laddr[1] == port]
-        try:
-            if listeners and listeners[0] is not None:
-                # conn.pid may be None if the current process doesn't have
-                # permission to identify the listening process!  Additionally,
-                # listeners may have more than one element if separate
-                # sockets have bound the same port on separate interfaces.
-                # We currently only have UI to notify the user about one
-                # of them at a time.
-                pid = listeners[0]
-                name = psutil.Process(pid).name()
-                display = zope.component.getUtility(interfaces.IDisplay)
-                display.notification(
-                    "The program {0} (process ID {1}) is already listening "
-                    "on TCP port {2}. This will prevent us from binding to "
-                    "that port. Please stop the {0} program temporarily "
-                    "and then try again.".format(name, pid, port))
-                return True
-        except (psutil.NoSuchProcess, psutil.AccessDenied):
-            # Perhaps the result of a race where the process could have
-            # exited or relinquished the port (NoSuchProcess), or the result
-            # of an OS policy where we're not allowed to look up the process
-            # name (AccessDenied).
-            pass
-        return False
-
     # IAuthenticator method implementations follow
 
     def get_chall_pref(self, unused_domain):  # pylint: disable=no-self-use
@@ -383,7 +341,7 @@ class StandaloneAuthenticator(common.Plugin):
         if not self.tasks:
             raise ValueError("nothing for .perform() to do")
 
-        if self.already_listening(self.config.dvsni_port):
+        if util.already_listening(self.config.dvsni_port):
             # If we know a process is already listening on this port,
             # tell the user, and don't even attempt to bind it.  (This
             # test is Linux-specific and won't indicate that the port

letsencrypt/plugins/standalone/tests/authenticator_test.py

@@ -187,109 +187,6 @@ class SubprocSignalHandlerTest(unittest.TestCase):
         mock_exit.assert_called_once_with(0)
 
 
-class AlreadyListeningTest(unittest.TestCase):
-    """Tests for already_listening() method."""
-    def setUp(self):
-        from letsencrypt.plugins.standalone.authenticator import \
-            StandaloneAuthenticator
-        self.authenticator = StandaloneAuthenticator(config=CONFIG, name=None)
-
-    @mock.patch("letsencrypt.plugins.standalone.authenticator.psutil."
-                "net_connections")
-    @mock.patch("letsencrypt.plugins.standalone.authenticator.psutil.Process")
-    @mock.patch("letsencrypt.plugins.standalone.authenticator."
-                "zope.component.getUtility")
-    def test_race_condition(self, mock_get_utility, mock_process, mock_net):
-        # This tests a race condition, or permission problem, or OS
-        # incompatibility in which, for some reason, no process name can be
-        # found to match the identified listening PID.
-        from psutil._common import sconn
-        conns = [
-            sconn(fd=-1, family=2, type=1, laddr=("0.0.0.0", 30),
-                  raddr=(), status="LISTEN", pid=None),
-            sconn(fd=3, family=2, type=1, laddr=("192.168.5.10", 32783),
-                  raddr=("20.40.60.80", 22), status="ESTABLISHED", pid=1234),
-            sconn(fd=-1, family=10, type=1, laddr=("::1", 54321),
-                  raddr=("::1", 111), status="CLOSE_WAIT", pid=None),
-            sconn(fd=3, family=2, type=1, laddr=("0.0.0.0", 17),
-                  raddr=(), status="LISTEN", pid=4416)]
-        mock_net.return_value = conns
-        mock_process.side_effect = psutil.NoSuchProcess("No such PID")
-        # We simulate being unable to find the process name of PID 4416,
-        # which results in returning False.
-        self.assertFalse(self.authenticator.already_listening(17))
-        self.assertEqual(mock_get_utility.generic_notification.call_count, 0)
-        mock_process.assert_called_once_with(4416)
-
-    @mock.patch("letsencrypt.plugins.standalone.authenticator.psutil."
-                "net_connections")
-    @mock.patch("letsencrypt.plugins.standalone.authenticator.psutil.Process")
-    @mock.patch("letsencrypt.plugins.standalone.authenticator."
-                "zope.component.getUtility")
-    def test_not_listening(self, mock_get_utility, mock_process, mock_net):
-        from psutil._common import sconn
-        conns = [
-            sconn(fd=-1, family=2, type=1, laddr=("0.0.0.0", 30),
-                  raddr=(), status="LISTEN", pid=None),
-            sconn(fd=3, family=2, type=1, laddr=("192.168.5.10", 32783),
-                  raddr=("20.40.60.80", 22), status="ESTABLISHED", pid=1234),
-            sconn(fd=-1, family=10, type=1, laddr=("::1", 54321),
-                  raddr=("::1", 111), status="CLOSE_WAIT", pid=None)]
-        mock_net.return_value = conns
-        mock_process.name.return_value = "inetd"
-        self.assertFalse(self.authenticator.already_listening(17))
-        self.assertEqual(mock_get_utility.generic_notification.call_count, 0)
-        self.assertEqual(mock_process.call_count, 0)
-
-    @mock.patch("letsencrypt.plugins.standalone.authenticator.psutil."
-                "net_connections")
-    @mock.patch("letsencrypt.plugins.standalone.authenticator.psutil.Process")
-    @mock.patch("letsencrypt.plugins.standalone.authenticator."
-                "zope.component.getUtility")
-    def test_listening_ipv4(self, mock_get_utility, mock_process, mock_net):
-        from psutil._common import sconn
-        conns = [
-            sconn(fd=-1, family=2, type=1, laddr=("0.0.0.0", 30),
-                  raddr=(), status="LISTEN", pid=None),
-            sconn(fd=3, family=2, type=1, laddr=("192.168.5.10", 32783),
-                  raddr=("20.40.60.80", 22), status="ESTABLISHED", pid=1234),
-            sconn(fd=-1, family=10, type=1, laddr=("::1", 54321),
-                  raddr=("::1", 111), status="CLOSE_WAIT", pid=None),
-            sconn(fd=3, family=2, type=1, laddr=("0.0.0.0", 17),
-                  raddr=(), status="LISTEN", pid=4416)]
-        mock_net.return_value = conns
-        mock_process.name.return_value = "inetd"
-        result = self.authenticator.already_listening(17)
-        self.assertTrue(result)
-        self.assertEqual(mock_get_utility.call_count, 1)
-        mock_process.assert_called_once_with(4416)
-
-    @mock.patch("letsencrypt.plugins.standalone.authenticator.psutil."
-                "net_connections")
-    @mock.patch("letsencrypt.plugins.standalone.authenticator.psutil.Process")
-    @mock.patch("letsencrypt.plugins.standalone.authenticator."
-                "zope.component.getUtility")
-    def test_listening_ipv6(self, mock_get_utility, mock_process, mock_net):
-        from psutil._common import sconn
-        conns = [
-            sconn(fd=-1, family=2, type=1, laddr=("0.0.0.0", 30),
-                  raddr=(), status="LISTEN", pid=None),
-            sconn(fd=3, family=2, type=1, laddr=("192.168.5.10", 32783),
-                  raddr=("20.40.60.80", 22), status="ESTABLISHED", pid=1234),
-            sconn(fd=-1, family=10, type=1, laddr=("::1", 54321),
-                  raddr=("::1", 111), status="CLOSE_WAIT", pid=None),
-            sconn(fd=3, family=10, type=1, laddr=("::", 12345), raddr=(),
-                  status="LISTEN", pid=4420),
-            sconn(fd=3, family=2, type=1, laddr=("0.0.0.0", 17),
-                  raddr=(), status="LISTEN", pid=4416)]
-        mock_net.return_value = conns
-        mock_process.name.return_value = "inetd"
-        result = self.authenticator.already_listening(12345)
-        self.assertTrue(result)
-        self.assertEqual(mock_get_utility.call_count, 1)
-        mock_process.assert_called_once_with(4420)
-
-
 class PerformTest(unittest.TestCase):
     """Tests for perform() method."""
     def setUp(self):

letsencrypt/plugins/util.py

@@ -0,0 +1,49 @@
+"""Plugin utilities."""
+import socket
+
+import psutil
+import zope.component
+
+from letsencrypt import interfaces
+
+
+def already_listening(port):
+    """Check if a process is already listening on the port.
+
+    If so, also tell the user via a display notification.
+
+    .. warning::
+        On some operating systems, this function can only usefully be
+        run as root.
+
+    :param int port: The TCP port in question.
+    :returns: True or False."""
+
+    listeners = [conn.pid for conn in psutil.net_connections()
+                 if conn.status == 'LISTEN' and
+                 conn.type == socket.SOCK_STREAM and
+                 conn.laddr[1] == port]
+    try:
+        if listeners and listeners[0] is not None:
+            # conn.pid may be None if the current process doesn't have
+            # permission to identify the listening process!  Additionally,
+            # listeners may have more than one element if separate
+            # sockets have bound the same port on separate interfaces.
+            # We currently only have UI to notify the user about one
+            # of them at a time.
+            pid = listeners[0]
+            name = psutil.Process(pid).name()
+            display = zope.component.getUtility(interfaces.IDisplay)
+            display.notification(
+                "The program {0} (process ID {1}) is already listening "
+                "on TCP port {2}. This will prevent us from binding to "
+                "that port. Please stop the {0} program temporarily "
+                "and then try again.".format(name, pid, port))
+            return True
+    except (psutil.NoSuchProcess, psutil.AccessDenied):
+        # Perhaps the result of a race where the process could have
+        # exited or relinquished the port (NoSuchProcess), or the result
+        # of an OS policy where we're not allowed to look up the process
+        # name (AccessDenied).
+        pass
+    return False

letsencrypt/plugins/util_test.py

@@ -0,0 +1,103 @@
+"""Tests for letsencrypt.plugins.util."""
+import unittest
+
+import mock
+import psutil
+
+
+class AlreadyListeningTest(unittest.TestCase):
+    """Tests for letsencrypt.plugins.already_listening."""
+    def _call(self, *args, **kwargs):
+        from letsencrypt.plugins.util import already_listening
+        return already_listening(*args, **kwargs)
+
+    @mock.patch("letsencrypt.plugins.util.psutil.net_connections")
+    @mock.patch("letsencrypt.plugins.util.psutil.Process")
+    @mock.patch("letsencrypt.plugins.util.zope.component.getUtility")
+    def test_race_condition(self, mock_get_utility, mock_process, mock_net):
+        # This tests a race condition, or permission problem, or OS
+        # incompatibility in which, for some reason, no process name can be
+        # found to match the identified listening PID.
+        from psutil._common import sconn
+        conns = [
+            sconn(fd=-1, family=2, type=1, laddr=("0.0.0.0", 30),
+                  raddr=(), status="LISTEN", pid=None),
+            sconn(fd=3, family=2, type=1, laddr=("192.168.5.10", 32783),
+                  raddr=("20.40.60.80", 22), status="ESTABLISHED", pid=1234),
+            sconn(fd=-1, family=10, type=1, laddr=("::1", 54321),
+                  raddr=("::1", 111), status="CLOSE_WAIT", pid=None),
+            sconn(fd=3, family=2, type=1, laddr=("0.0.0.0", 17),
+                  raddr=(), status="LISTEN", pid=4416)]
+        mock_net.return_value = conns
+        mock_process.side_effect = psutil.NoSuchProcess("No such PID")
+        # We simulate being unable to find the process name of PID 4416,
+        # which results in returning False.
+        self.assertFalse(self._call(17))
+        self.assertEqual(mock_get_utility.generic_notification.call_count, 0)
+        mock_process.assert_called_once_with(4416)
+
+    @mock.patch("letsencrypt.plugins.util.psutil.net_connections")
+    @mock.patch("letsencrypt.plugins.util.psutil.Process")
+    @mock.patch("letsencrypt.plugins.util.zope.component.getUtility")
+    def test_not_listening(self, mock_get_utility, mock_process, mock_net):
+        from psutil._common import sconn
+        conns = [
+            sconn(fd=-1, family=2, type=1, laddr=("0.0.0.0", 30),
+                  raddr=(), status="LISTEN", pid=None),
+            sconn(fd=3, family=2, type=1, laddr=("192.168.5.10", 32783),
+                  raddr=("20.40.60.80", 22), status="ESTABLISHED", pid=1234),
+            sconn(fd=-1, family=10, type=1, laddr=("::1", 54321),
+                  raddr=("::1", 111), status="CLOSE_WAIT", pid=None)]
+        mock_net.return_value = conns
+        mock_process.name.return_value = "inetd"
+        self.assertFalse(self._call(17))
+        self.assertEqual(mock_get_utility.generic_notification.call_count, 0)
+        self.assertEqual(mock_process.call_count, 0)
+
+    @mock.patch("letsencrypt.plugins.util.psutil.net_connections")
+    @mock.patch("letsencrypt.plugins.util.psutil.Process")
+    @mock.patch("letsencrypt.plugins.util.zope.component.getUtility")
+    def test_listening_ipv4(self, mock_get_utility, mock_process, mock_net):
+        from psutil._common import sconn
+        conns = [
+            sconn(fd=-1, family=2, type=1, laddr=("0.0.0.0", 30),
+                  raddr=(), status="LISTEN", pid=None),
+            sconn(fd=3, family=2, type=1, laddr=("192.168.5.10", 32783),
+                  raddr=("20.40.60.80", 22), status="ESTABLISHED", pid=1234),
+            sconn(fd=-1, family=10, type=1, laddr=("::1", 54321),
+                  raddr=("::1", 111), status="CLOSE_WAIT", pid=None),
+            sconn(fd=3, family=2, type=1, laddr=("0.0.0.0", 17),
+                  raddr=(), status="LISTEN", pid=4416)]
+        mock_net.return_value = conns
+        mock_process.name.return_value = "inetd"
+        result = self._call(17)
+        self.assertTrue(result)
+        self.assertEqual(mock_get_utility.call_count, 1)
+        mock_process.assert_called_once_with(4416)
+
+    @mock.patch("letsencrypt.plugins.util.psutil.net_connections")
+    @mock.patch("letsencrypt.plugins.util.psutil.Process")
+    @mock.patch("letsencrypt.plugins.util.zope.component.getUtility")
+    def test_listening_ipv6(self, mock_get_utility, mock_process, mock_net):
+        from psutil._common import sconn
+        conns = [
+            sconn(fd=-1, family=2, type=1, laddr=("0.0.0.0", 30),
+                  raddr=(), status="LISTEN", pid=None),
+            sconn(fd=3, family=2, type=1, laddr=("192.168.5.10", 32783),
+                  raddr=("20.40.60.80", 22), status="ESTABLISHED", pid=1234),
+            sconn(fd=-1, family=10, type=1, laddr=("::1", 54321),
+                  raddr=("::1", 111), status="CLOSE_WAIT", pid=None),
+            sconn(fd=3, family=10, type=1, laddr=("::", 12345), raddr=(),
+                  status="LISTEN", pid=4420),
+            sconn(fd=3, family=2, type=1, laddr=("0.0.0.0", 17),
+                  raddr=(), status="LISTEN", pid=4416)]
+        mock_net.return_value = conns
+        mock_process.name.return_value = "inetd"
+        result = self._call(12345)
+        self.assertTrue(result)
+        self.assertEqual(mock_get_utility.call_count, 1)
+        mock_process.assert_called_once_with(4420)
+
+
+if __name__ == "__main__":
+    unittest.main()  # pragma: no cover