testnode: make killall support processes with changed title

testnode uses ProcessManager.killall to terminate all processes from a
path. To determine if a process is from a path, it looks at the command
line. This does not work for processes using setproctitle to change
their command line.

We can see in ps:

    $ ps -edf | grep nginx
    slapuse+ 115059  45574  0 16:14 ?        00:00:00 nginx: master process /srv/slapgrid/slappart46/t/cvt/i/0/tmp/shared/nginx/6d79cb0e7d81dce1be97eec8a5712f08/sbin/nginx -c /srv/slapgrid/slappart46/t/cvt/i/0/tmp/inst/T-0/etc/nginx-master-introspection.conf
    slapuse+ 115090 115059  0 16:14 ?        00:00:00 nginx: worker process

or by looking at cmdline, which is what psutil.Process.cmdline is using:

    $ cat /proc/115090/cmdline
    nginx: worker process

and that's why sometimes when cancelling a software release test while
it is running tests from a software using nginx, some processes are
leaked, they keep using the port and next test running on this testnode
fail.

In that case, killall is called with /srv/slapgrid/slappart46/t/cvt , we
can not find such process with cmdline, but we can extend this heuristic
to use the current working directory:

    $ ls -al /proc/115090/cwd
    lrwxrwxrwx 1 slapuser46 slapuser46 0 Oct 19 16:16 /proc/115090/cwd -> /srv/slapgrid/slappart46/t/cvt/i/0/tmp/inst/T-0

This also applies an optimization of only considering processes of the
current unix user.

erp5/tests/testProcessManager.py

+##############################################################################
+#
+# Copyright (c) 2023 Nexedi SA and Contributors. All Rights Reserved.
+#
+# WARNING: This program as such is intended to be used by professional
+# programmers who take the whole responsibility of assessing all potential
+# consequences resulting from its eventual inadequacies and bugs
+# End users who are looking for a ready-to-use solution with commercial
+# guarantees and support are strongly advised to contract a Free Software
+# Service Company
+#
+# This program is Free Software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 3
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+#
+##############################################################################
+
+import os
+import shutil
+import subprocess
+import tempfile
+import unittest
+import sys
+import time
+
+from erp5.util.testnode.ProcessManager import ProcessManager
+
+
+class TestProcessManagerKillAll(unittest.TestCase):
+  def setUp(self):
+    self.path = tempfile.mkdtemp()
+    self.addCleanup(shutil.rmtree, self.path)
+    self.script = os.path.join(self.path, 'script')
+    with open(self.script, 'w') as f:
+      f.write('#!/bin/sh\nsleep 30')
+    os.chmod(self.script, 0o700)
+    self.pm = ProcessManager()
+    self.start_time = time.time()
+
+  def tearDown(self):
+    self.assertLess(
+      time.time() - self.start_time,
+      29,
+      'Process did not stop in time',
+    )
+
+  def test_killall_script_in_path(self):
+    process = subprocess.Popen([self.script])
+    self.pm.killall(self.path)
+    process.communicate()
+    self.assertTrue(process.poll())
+
+  def test_killall_another_path(self):
+    process = subprocess.Popen([self.script])
+    self.pm.killall("another path")
+    self.assertIsNone(process.poll())
+    process.kill()
+    process.communicate()
+    process.wait()
+
+  def test_killall_proctitle_cwd(self):
+    with open(self.script, 'w') as f:
+      f.write('''if 1:
+      import setproctitle
+      setproctitle.setproctitle('hidden')
+      import time
+      time.sleep(30)
+      ''')
+    process = subprocess.Popen([sys.executable, self.script], cwd=self.path)
+    self.pm.killall(self.path)
+    process.communicate()
+    self.assertTrue(process.poll())

erp5/util/testnode/ProcessManager.py

@@ -24,13 +24,14 @@
 # Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 #
 ##############################################################################
+import getpass
 import os
 import psutil
 import re
-import subprocess
-import threading
 import signal
+import subprocess
 import sys
+import threading
 import time
 from . import logger
 
@@ -204,15 +205,18 @@ class ProcessManager(object):
         re.findall(br'^  (--\w+)', self.spawn(program_path, '--help')['stdout'], re.M))
 
   def killall(self, path):
-    """
-    Kill processes of given name, only if they're orphan or subprocesses of
-    the testnode.
+    """Kill all process from the user running in a given path
+
+    Processes from a given path are either executables contained in path or
+    executables running with current directory contained in path.
     """
     to_kill_list = []
-    pid = os.getpid()
-    for process in psutil.process_iter():
+    current_username = getpass.getuser()
+    for process in psutil.process_iter(['username']):
+      if process.info['username'] != current_username:
+        continue
       try:
-        if not(path in str(process.cmdline())):
+        if path not in str(process.cmdline()) and path not in process.cwd():
           continue
       except (psutil.AccessDenied, psutil.NoSuchProcess):
         continue

setup.py

@@ -60,6 +60,7 @@ setup(name=name,
         'test': [
           'mock; python_version < "3"',
           'psutil >= 0.5.0',
+          'setproctitle',
           'slapos.core',
           'xml_marshaller',
         ]