[CLI][Multi ASIC] Allow commands that don't support "-n" option to be run with "sudo ip netns.." option.

src/sonic-py-common/sonic_py_common/multi_asic.py

@@ -136,17 +136,49 @@ def get_asic_id_from_name(asic_name):
  raise ValueError('Unknown asic namespace name {}'.format(asic_name))
 
 
+def get_current_namespace():
+ """
+ This API returns the network namespace in which it is
+ invoked. In case of global namepace the API returns None
+ """
+
+ net_namespace = None
+ command = ["/bin/ip netns identify", str(os.getpid())]
+ proc = subprocess.Popen(command,
+ stdout=subprocess.PIPE,
+ shell=True,
+ stderr=subprocess.STDOUT)
+ try:
+ stdout, stderr = proc.communicate()
+ if proc.returncode != 0:
+ raise RuntimeError(
+ "Command {} failed with stderr {}".format(command, stderr)
+ )
+ if stdout.rstrip('\n') != "":
+ net_namespace = stdout.rstrip('\n')
+ except OSError as e:
+ raise OSError("Error running command {}".format(command))
+
+ return net_namespace
+
+
 def get_namespaces_from_linux():
  """
  In a multi asic platform, each ASIC is in a Linux Namespace.
- This method returns list of all the Namespace present on the device
+ This method returns the asic namespace under which this is invoked,
+ if namespace is None (global namespace) it returns list of all
+ the Namespace present on the device
 
  Note: It is preferable to use this function only when config_db is not
  available. When configdb is available use get_all_namespaces()
 
  Returns:
  List of the namespaces present in the system
  """
+ current_ns = get_current_namespace()
+ if current_ns:
+ return [current_ns]
+
  ns_list = []
  for path in glob.glob(NAMESPACE_PATH_GLOB):
  ns = os.path.basename(path)