fix: exiting earlier to avoid exceptions from gRPC calls (#3463)

* feat: adding logging and avoid recursively trying to exit even if we have already tried.

* feat: adding logging and avoid recursively trying to exit even if we have already tried.

* feat: avoid issuing gRPC calls when exiting. Added more logging while exiting.

* chore: adding changelog file 3463.fixed.md

* fix: test

---------

Co-authored-by: pyansys-ci-bot <[email protected]>

doc/changelog.d/3463.fixed.md

@@ -0,0 +1 @@
+fix: exiting earlier to avoid exceptions from gRPC calls

src/ansys/mapdl/core/errors.py

@@ -323,6 +323,7 @@ def wrapper(*args, **kwargs):
             except grpc.RpcError as error:
 
                 mapdl = retrieve_mapdl_from_args(args)
+                mapdl._log.debug("A gRPC error has been detected.")
 
                 i_attemps += 1
                 if i_attemps <= n_attempts:
@@ -443,9 +444,11 @@ def handle_generic_grpc_error(error, func, args, kwargs, reason="", suggestion="
     else:
         # Making sure we do not keep executing gRPC calls.
         mapdl._exited = True
+        mapdl._exiting = True
 
         # Must close unfinished processes
         mapdl._close_process()
+        mapdl._exiting = False
         raise MapdlExitedError(msg)
 
 

src/ansys/mapdl/core/mapdl_grpc.py

@@ -1061,14 +1061,19 @@ def exit(self, save=False, force=False, **kwargs):
         >>> mapdl.exit()
         """
         # check if permitted to start (and hence exit) instances
+        self._log.debug(
+            f"Exiting MAPLD gRPC instance {self.ip}:{self.port} on '{self._path}'."
+        )
 
         if self._exited is None:
+            self._log.debug("'self._exited' is none.")
             return  # Some edge cases the class object is not completely initialized but the __del__ method
             # is called when exiting python. So, early exit here instead an error in the following
             # self.directory command.
             # See issue #1796
         elif self._exited:
             # Already exited.
+            self._log.debug("Already exited")
             return
 
         if save:
@@ -1091,10 +1096,9 @@ def exit(self, save=False, force=False, **kwargs):
                 return
 
         self._exiting = True
-        self._log.debug("Exiting MAPDL")
 
         if not kwargs.pop("fake_exit", False):
-            # This cannot should not be faked
+            # This cannot/should not be faked
             if self._local:
                 mapdl_path = self.directory
                 self._cache_pids()  # Recache processes
@@ -1152,6 +1156,10 @@ def _kill_server(self):
         a local process.
 
         """
+        if self._exited:
+            self._log.debug("MAPDL server already exited")
+            return
+
         try:
             self._log.debug("Killing MAPDL server")
         except ValueError:
@@ -1233,6 +1241,7 @@ def _close_process(self, timeout=2):  # pragma: no cover
         if self.is_alive:
             raise MapdlRuntimeError("MAPDL could not be exited.")
         else:
+            self._log.debug("All MAPDL processes exited")
             self._exited = True
 
     def _cache_pids(self):
@@ -1243,6 +1252,7 @@ def _cache_pids(self):
         processes.
 
         """
+        self._log.debug("Caching PIDs")
         self._pids = []
 
         for filename in self.list_files():
@@ -1264,11 +1274,15 @@ def _cache_pids(self):
             try:
                 parent = psutil.Process(parent_pid)
             except psutil.NoSuchProcess:
+                self._log.debug(f"Parent process does not exist.")
                 return
+
             children = parent.children(recursive=True)
 
             self._pids = [parent_pid] + [each.pid for each in children]
 
+        self._log.debug(f"Recaching PIDs: {self._pids}")
+
     def _remove_lock_file(self, mapdl_path=None):
         """Removes the lock file.
 
@@ -2625,10 +2639,16 @@ def is_alive(self) -> bool:
         if self._exited:
             self._log.debug("MAPDL instance is not alive because it is exited.")
             return False
+
         if self.busy:
             self._log.debug("MAPDL instance is alive because it is busy.")
             return True
 
+        if self._exiting:
+            # It should be exiting so we should not issue gRPC calls
+            self._log.debug("MAPDL instance is expected to be exiting")
+            return False
+
         try:
             check = bool(self._ctrl("VERSION"))
             if check:
@@ -2642,6 +2662,9 @@ def is_alive(self) -> bool:
             return check
 
         except Exception as error:
+            if self._exited:
+                return False
+
             self._log.debug(
                 f"MAPDL instance is not alive because retrieving version failed with:\n{error}"
             )