T7363: add pid aware initialization

2 files changed, 44 insertions, 23 deletions

diff --git a/python/vyos/configsession.py b/python/vyos/configsession.py
index 6490e6feb..a070736cd 100644
--- a/python/vyos/configsession.py
+++ b/python/vyos/configsession.py
@@ -179,26 +179,29 @@ class ConfigSession(object):
             self._vyconf_session = None
 
     def __del__(self):
-        try:
-            output = (
-                subprocess.check_output(
-                    [CLI_SHELL_API, 'teardownSession'], env=self.__session_env
+        if self._vyconf_session is None:
+            try:
+                output = (
+                    subprocess.check_output(
+                        [CLI_SHELL_API, 'teardownSession'], env=self.__session_env
+                    )
+                    .decode()
+                    .strip()
                 )
-                .decode()
-                .strip()
-            )
-            if output:
+                if output:
+                    print(
+                        'cli-shell-api teardownSession output for sesion {0}: {1}'.format(
+                            self.__session_id, output
+                        ),
+                        file=sys.stderr,
+                    )
+            except Exception as e:
                 print(
-                    'cli-shell-api teardownSession output for sesion {0}: {1}'.format(
-                        self.__session_id, output
-                    ),
+                    'Could not tear down session {0}: {1}'.format(self.__session_id, e),
                     file=sys.stderr,
                 )
-        except Exception as e:
-            print(
-                'Could not tear down session {0}: {1}'.format(self.__session_id, e),
-                file=sys.stderr,
-            )
+        else:
+            self._vyconf_session.teardown()
 
     def __run_command(self, cmd_list):
         p = subprocess.Popen(
diff --git a/python/vyos/vyconf_session.py b/python/vyos/vyconf_session.py
index 506095625..cbf2fc873 100644
--- a/python/vyos/vyconf_session.py
+++ b/python/vyos/vyconf_session.py
@@ -15,6 +15,7 @@
 #
 #
 
+import os
 import tempfile
 import shutil
 from functools import wraps
@@ -24,6 +25,7 @@ from vyos.proto import vyconf_client
 from vyos.migrate import ConfigMigrate
 from vyos.migrate import ConfigMigrateError
 from vyos.component_version import append_system_version
+from vyos.utils.session import in_config_session
 
 
 def output(o):
@@ -35,14 +37,35 @@ def output(o):
 
 
 class VyconfSession:
-    def __init__(self, token: str = None, on_error: Type[Exception] = None):
+    def __init__(
+        self, token: str = None, pid: int = None, on_error: Type[Exception] = None
+    ):
+        self.pid = os.getpid() if pid is None else pid
         if token is None:
-            out = vyconf_client.send_request('setup_session')
+            # CLI applications with arg pid=getppid() allow coordination
+            # with the ambient session; other uses (such as ConfigSession)
+            # may default to self pid
+            out = vyconf_client.send_request('session_of_pid', client_pid=self.pid)
+            if out.output is None:
+                out = vyconf_client.send_request('setup_session', client_pid=self.pid)
             self.__token = out.output
         else:
+            out = vyconf_client.send_request(
+                'session_update_pid', token=token, client_pid=self.pid
+            )
+            if out.status:
+                raise ValueError(f'No existing session for token: {token}')
             self.__token = token
 
         self.on_error = on_error
+        self.in_config_session = in_config_session()
+
+    def __del__(self):
+        if not self.in_config_session:
+            self.teardown()
+
+    def teardown(self):
+        vyconf_client.send_request('teardown', token=self.__token)
 
     @staticmethod
     def raise_exception(f):
@@ -116,8 +139,3 @@ class VyconfSession:
             path = []
         out = vyconf_client.send_request('show_config', token=self.__token, path=path)
         return output(out), out.status
-
-    def __del__(self):
-        out = vyconf_client.send_request('teardown', token=self.__token)
-        if out.status:
-            print(f'Could not tear down session {self.__token}: {output(out)}')