def start(self):
"""Start the daemon.
Args:
None
Returns:
"""
# Check for a pidfile to see if the daemon already runs
try:
with open(self.pidfile, 'r') as pf_handle:
pid = int(pf_handle.read().strip())
except IOError:
pid = None
if pid:
log_message = (
'PID file: {} already exists. Daemon already running?'
''.format(self.pidfile))
log.log2die(1062, log_message)
# Start the daemon
self.daemonize()
# Log success
log_message = ('Daemon {} started - PID file: {}'
''.format(self.name, self.pidfile))
log.log2info(1070, log_message)
# Run code for daemon
self.run()
def populate(self, data_in):
"""Populate data for agent to eventually send to server.
Args:
data_in: dict of datapoint values from agent
timeseries: TimeSeries data if True
Returns:
None
"""
# Initialize data
data = deepcopy(data_in)
# Validate base_type
if len(data) != 1 or isinstance(data, defaultdict) is False:
log_message = 'Agent data "{}" is invalid'.format(data)
log.log2die(1025, log_message)
# Get a description to use for label value
for label in data.keys():
description = self._lang.label_description(label)
data[label]['description'] = description
break
# Add data to appropriate self._data key
if data[label]['base_type'] is not None:
self._data['devices'][self._devicename]['timeseries'].update(data)
else:
self._data['devices'][self._devicename]['timefixed'].update(data)
def _ip_binding():
"""Create IPv4 / IPv6 binding for Gunicorn.
Args:
None
Returns:
result: bind
"""
# Initialize key variables
config = CONFIG
ipv4 = False
ip_address = config.listen_address()
# Check IP address type
try:
ip_object = ipaddress.ip_address(ip_address)
except:
log_message = (
'The {} IP address in the configuration file is incorrectly '
'formatted'.format(ip_address))
log.log2die(1234, log_message)
# Is this an IPv4 address?
ipv4 = isinstance(ip_object, ipaddress.IPv4Address)
if ipv4 is True:
result = '{}:{}'.format(ip_address, config.bind_port())
else:
result = '[{}]:{}'.format(ip_address, config.bind_port())
return result
def agent_cache_directory(self):
"""Determine the agent_cache_directory.
Args:
None
Returns:
value: configured agent_cache_directory
"""
# Initialize key variables
key = 'main'
sub_key = 'agent_cache_directory'
# Get result
_value = _key_sub_key(key, sub_key, self._config_dict)
# Expand linux ~ notation for home directories if provided.
value = os.path.expanduser(_value)
# Check if value exists
if os.path.isdir(value) is False:
log_message = ('agent_cache_directory: "{}" '
'in configuration doesn\'t exist!'.format(value))
log.log2die(1031, log_message)
# Return
return value
def log_directory(self):
"""Get log_directory.
Args:
None
Returns:
result: result
"""
# Get result
sub_key = 'log_directory'
result = None
key = 'main'
# Get new result
_result = _key_sub_key(key, sub_key, self._config_dict)
# Expand linux ~ notation for home directories if provided.
result = os.path.expanduser(_result)
# Check if value exists
if os.path.isdir(result) is False:
log_message = ('log_directory: "{}" '
'in configuration doesn\'t exist!'.format(result))
log.log2die(1010, log_message)
# Return
return result
def stop(self):
"""Stop the daemon.
Args:
None
Returns:
"""
# Get the pid from the pidfile
try:
with open(self.pidfile, 'r') as pf_handle:
pid = int(pf_handle.read().strip())
except IOError:
pid = None
if not pid:
log_message = ('PID file: {} does not exist. Daemon not running?'
''.format(self.pidfile))
log.log2warning(1063, log_message)
# Not an error in a restart
return
# Try killing the daemon process
try:
while 1:
if self.lockfile is None:
os.kill(pid, signal.SIGTERM)
else:
time.sleep(0.3)
if os.path.exists(self.lockfile) is True:
continue
else:
os.kill(pid, signal.SIGTERM)
time.sleep(0.3)
except OSError as err:
error = str(err.args)
if error.find("No such process") > 0:
self.delpid()
self.dellock()
else:
log_message = (str(err.args))
log_message = ('{} - PID file: {}'.format(
log_message, self.pidfile))
log.log2die(1068, log_message)
except:
log_message = ('Unknown daemon "stop" error for PID file: {}'
''.format(self.pidfile))
log.log2die(1066, log_message)
# Log success
self.delpid()
self.dellock()
log_message = ('Daemon {} stopped - PID file: {}'
''.format(self.name, self.pidfile))
log.log2info(1071, log_message)
def daemonize(self):
"""Deamonize class. UNIX double fork mechanism.
Args:
None
Returns:
None
"""
# Create a parent process that will manage the child
# when the code using this class is done.
try:
pid = os.fork()
if pid > 0:
# Exit first parent
sys.exit(0)
except OSError as err:
log_message = 'Daemon fork #1 failed: {}'.format(err)
log_message = '{} - PID file: {}'.format(log_message, self.pidfile)
log.log2die(1060, log_message)
# Decouple from parent environment
os.chdir('/')
os.setsid()
os.umask(0)
# Do second fork
try:
pid = os.fork()
if pid > 0:
# exit from second parent
sys.exit(0)
except OSError as err:
log_message = 'Daemon fork #2 failed: {}'.format(err)
log_message = '{} - PID file: {}'.format(log_message, self.pidfile)
log.log2die(1061, log_message)
# Redirect standard file descriptors
sys.stdout.flush()
sys.stderr.flush()
f_handle_si = open(os.devnull, 'r')
f_handle_so = open(os.devnull, 'a+')
f_handle_se = open(os.devnull, 'a+')
os.dup2(f_handle_si.fileno(), sys.stdin.fileno())
os.dup2(f_handle_so.fileno(), sys.stdout.fileno())
os.dup2(f_handle_se.fileno(), sys.stderr.fileno())
# write pidfile
atexit.register(self.delpid)
pid = str(os.getpid())
with open(self.pidfile, 'w+') as f_handle:
f_handle.write(pid + '\n')
def purge(self):
"""Purge data from cache by posting to central server.
Args:
None
Returns:
success: "True: if successful
"""
# Initialize key variables
agent_id = self._data['agent_id']
# Add files in cache directory to list only if they match the
# cache suffix
all_filenames = [
filename for filename in os.listdir(self._cache_dir)
if os.path.isfile(os.path.join(self._cache_dir, filename))
]
filenames = [
filename for filename in all_filenames
if filename.endswith(self._cache_filename_suffix)
]
# Read cache file
for filename in filenames:
# Only post files for our own UID value
if agent_id not in filename:
continue
# Get the full filepath for the cache file and post
filepath = os.path.join(self._cache_dir, filename)
with open(filepath, 'r') as f_handle:
try:
data = json.load(f_handle)
except:
# Log removal
log_message = (
'Error reading previously cached agent data file {} '
'for agent {}. May be corrupted.'
''.format(filepath, self._agent_name))
log.log2die(1064, log_message)
# Post file
success = self.post(save=False, data=data)
# Delete file if successful
if success is True:
os.remove(filepath)
# Log removal
log_message = ('Purging cache file {} after successfully '
'contacting server {}'
''.format(filepath, self._url))
log.log2info(1029, log_message)
def read_yaml_files(config_directory):
"""Read the contents of all yaml files in a directory.
Args:
config_directory: Directory with configuration files
Returns:
config_dict: Dict of yaml read
"""
# Initialize key variables
yaml_found = False
yaml_from_file = ''
all_yaml_read = ''
if os.path.isdir(config_directory) is False:
log_message = ('Configuration directory "{}" '
'doesn\'t exist!'.format(config_directory))
log.log2die(1009, log_message)
# Cycle through list of files in directory
for filename in os.listdir(config_directory):
# Examine all the '.yaml' files in directory
if filename.endswith('.yaml'):
# YAML files found
yaml_found = True
# Read file and add to string
file_path = '{}/{}'.format(config_directory, filename)
try:
with open(file_path, 'r') as file_handle:
yaml_from_file = file_handle.read()
except:
log_message = ('Error reading file {}. Check permissions, '
'existence and file syntax.'
''.format(file_path))
log.log2die(1065, log_message)
# Append yaml from file to all yaml previously read
all_yaml_read = '{}\n{}'.format(all_yaml_read, yaml_from_file)
# Verify YAML files found in directory. We cannot use logging as it
# requires a logfile location from the configuration directory to work
# properly
if yaml_found is False:
log_message = (
'No configuration files found in directory "{}" with ".yaml" '
'extension.'.format(config_directory))
print(log_message)
sys.exit(1)
# Return
config_dict = yaml.safe_load(all_yaml_read)
return config_dict
def _mkdir(directory):
"""Create a directory if it doesn't already exist.
Args:
directory: Directory name
Returns:
None
"""
# Do work
if os.path.exists(directory) is False:
os.makedirs(directory, mode=0o775)
else:
if os.path.isfile(directory) is True:
log_message = ('{} is not a directory.' ''.format(directory))
log.log2die(1043, log_message)
def agents(self):
"""Get agents.
Args:
None
Returns:
result: list of agents
"""
# Initialize key variables
key = 'agents'
result = None
# Verify data
if key not in self._config_dict:
log_message = ('No agents configured')
log.log2die(1100, log_message)
# Process agents
result = self._config_dict[key]
# Return
return result
