Fix unittest failures when stopping the server

isrgomez · isrgomez · commit 5d4967821c31 · 2018-06-20T16:38:10.000-05:00
The stopping server mechanism fails due to the wrong PID used to
stop the server, the PID used is the one from the process that
start the server, instead of the mysqld process itself.

This patch changes the wrong behavior to always get the PID from
the PID file to stop the server. In addition this patch adds new
logging entries to facilitate the debug of unittest that requires
to stop the server.
diff --git a/tests/mysqld.py b/tests/mysqld.py
@@ -106,7 +106,9 @@ def process_running(pid):
         for name, apid, _ in lines:
             name = name.decode('utf-8')
             if name == EXEC_MYSQLD and pid == int(apid):
+                LOGGER.debug("Process %d is running.", pid)
                 return True
+        LOGGER.debug("Process %d not running.", pid)
         return False
 
     # We are on a UNIX-like system
@@ -328,12 +330,11 @@ def _start_server(self):
         except (OSError, ValueError) as err:
             raise MySQLServerError(err)
 
-    def _stop_server(self):
+    def _stop_server(self, pid=None):
         """Stop the MySQL server"""
-        if not self._process:
-            return False
+        pid = pid if pid is not None else get_pid(self._pid_file)
         try:
-            process_terminate(self._process.pid)
+            process_terminate(pid)
         except (OSError, ValueError) as err:
             raise MySQLServerError(err)
 
@@ -646,6 +647,7 @@ def update_config(self, **kwargs):
             sys.exit(1)
 
     def start(self, **kwargs):
+        LOGGER.debug("Attempting to start MySQL server %s", self.name)
         if self.check_running():
             LOGGER.error("MySQL server '{name}' already running".format(
                 name=self.name))
@@ -691,23 +693,31 @@ def stop(self):
         """
         pid = get_pid(self._pid_file)
         if not pid:
+            LOGGER.error("Process id not found, unable to stop MySQL server.")
             return
-        try:
-            if not self._stop_server():
-                process_terminate(pid)
-        except (MySQLServerError, OSError) as err:
-            if self._debug is True:
-                raise
-            LOGGER.error("Failed stopping MySQL server '{name}': "
-                         "{error}".format(error=str(err), name=self._name))
-            sys.exit(1)
-        else:
-            time.sleep(3)
+        LOGGER.debug("Attempting to stop MySQL server %s (pid=%s).",
+                     self._name, pid)
+        tries = 5
+        while tries > 0:
+            try:
+                self._stop_server(pid)
+            except (MySQLServerError, OSError) as err:
+                LOGGER.error("Failed stopping MySQL server '{name}': "
+                             "{error}".format(error=str(err), name=self._name))
+                if self._debug is True:
+                    raise
+                sys.exit(1)
+            else:
+                LOGGER.debug("Waiting for MySQL server to stop...")
+                time.sleep(1)
+                if not self.check_running(pid):
+                    LOGGER.debug("MySQL server stopped '{name}' "
+                                 "(pid={pid})".format(pid=pid, name=self._name))
+                    return True
+            tries =- 1
 
-        if self.check_running(pid):
-            LOGGER.debug("MySQL server stopped '{name}' "
-                        "(pid={pid})".format(pid=pid, name=self._name))
-            return True
+        LOGGER.error("Failed stopping MySQL server '{name}': "
+                     "{error}".format(error=str(err), name=self._name))
 
         return False
 
@@ -734,7 +744,7 @@ def check_running(self, pid=None):
         """
         pid = pid or get_pid(self._pid_file)
         if pid:
-            LOGGER.debug("Got PID %d", pid)
+            LOGGER.debug("Checking PID %d", pid)
             return process_running(pid)
 
         return False
