def _get_validator_pid(self, node_name):
pid_file = os.path.join(self._state_dir, "{}.pid".format(node_name))
max_attempts = 3
attempts = 0
while attempts < max_attempts:
if os.path.exists(pid_file):
with open(pid_file, 'r') as fd:
try:
return int(fd.readline())
except ValueError:
if attempts >= max_attempts:
raise ManagementError(
"invalid pid file: {}".format(pid_file))
time.sleep(1)
attempts = attempts + 1
raise ManagementError("no such file: {}".format(pid_file))
def is_running(self, node_name):
pid_file = os.path.join(self._state_dir, "{}.pid".format(node_name))
if os.path.exists(pid_file):
with open(pid_file, 'r') as fd:
try:
pid = int(fd.readline())
except ValueError:
raise ManagementError(
"invalid pid file: {}".format(pid_file))
if psutil.pid_exists(pid):
return True
return False
def get_executable_script(script_name):
'''
Searches PATH environmental variable to find the information needed to
execute a script.
Args:
script_name: the name of the 'executable' script
Returns:
ret_val (list<str>): A list containing the python executable, and the
full path to the script. Includes sys.executable, because certain
operating systems cannot execute scripts directly.
'''
ret_val = None
if 'PATH' not in os.environ:
raise ManagementError('no PATH environmental variable')
search_path = os.environ['PATH']
for directory in search_path.split(os.pathsep):
if os.path.exists(os.path.join(directory, script_name)):
ret_val = os.path.join(directory, script_name)
break
if ret_val is not None:
ret_val = [sys.executable, ret_val]
else:
raise ManagementError("could not locate %s" % (script_name))
return ret_val