nginx-amplify-agent/amplify/ext/mysql/managers.py

263 lines
9.3 KiB
Python

# -*- coding: utf-8 -*-
import hashlib
import psutil
from amplify.agent.common.context import context
from amplify.agent.common.util import subp
from amplify.agent.managers.abstract import launch_method_supported
from amplify.agent.data.eventd import INFO
from amplify.ext.abstract.manager import ExtObjectManager
from amplify.ext.mysql.util import PS_CMD, master_parser, ps_parser
from amplify.ext.mysql import AMPLIFY_EXT_KEY
from amplify.agent.common.util.configtypes import boolean
from amplify.ext.mysql.objects import MySQLObject
__author__ = "Andrew Alexeev"
__copyright__ = "Copyright (C) Nginx Inc. All rights reserved."
__license__ = ""
__maintainer__ = "Mike Belov"
__email__ = "dedm@nginx.com"
class MySQLManager(ExtObjectManager):
"""
Manager for MySQL objects.
"""
ext = AMPLIFY_EXT_KEY
name = 'mysql_manager'
type = 'mysql'
types = ('mysql',)
def _discover_objects(self):
# save the current ids
existing_hashes = [
obj.definition_hash
for obj in self.objects.find_all(types=self.types)
]
discovered_hashes = []
if boolean(context.app_config['mysql'].get('remote', False)):
mysql_daemons = self._find_remote()
else:
mysql_daemons = self._find_local()
while len(mysql_daemons):
try:
data = mysql_daemons.pop()
definition = {
'type': 'mysql',
'local_id': data['local_id'],
'root_uuid': context.uuid
}
definition_hash = MySQLObject.hash(definition)
discovered_hashes.append(definition_hash)
if definition_hash not in existing_hashes:
# New object -- create it
new_obj = MySQLObject(data=data)
# Send discover event.
new_obj.eventd.event(
level=INFO,
message='mysqld process found, pid %s' % new_obj.pid
)
self.objects.register(new_obj, parent_id=self.objects.root_id)
elif definition_hash in existing_hashes:
for obj in self.objects.find_all(types=self.types):
if obj.definition_hash == definition_hash:
current_obj = obj
break
if current_obj.pid != data['pid']:
# PIDs changed... MySQL must have been restarted
context.log.debug(
'mysqld was restarted (pid was %s now %s)' % (
current_obj.pid, data['pid']
)
)
new_obj = MySQLObject(data=data)
# send MySQL restart event
new_obj.eventd.event(
level=INFO,
message='mysqld process was restarted, new pid %s, old pid %s' % (
new_obj.pid,
current_obj.pid
)
)
# stop and un-register children
children_objects = self.objects.find_all(
obj_id=current_obj.id,
children=True,
include_self=False
)
for child_obj in children_objects:
child_obj.stop()
self.objects.unregister(obj=child_obj)
# un-register old object
self.objects.unregister(current_obj)
# stop old object
current_obj.stop()
self.objects.register(new_obj, parent_id=self.objects.root_id)
except psutil.NoSuchProcess:
context.log.debug('mysqld is restarting/reloading, pids are changing, agent is waiting')
# check if we left something in objects (MySQL could be stopped or something)
dropped_hashes = list(filter(lambda x: x not in discovered_hashes, existing_hashes))
if len(dropped_hashes) == 0:
return
for dropped_hash in dropped_hashes:
for obj in self.objects.find_all(types=self.types):
if obj.definition_hash == dropped_hash:
dropped_obj = obj
break
context.log.debug('mysqld was stopped (pid was %s)' % dropped_obj.pid)
# stop and un-register children
children_objects = self.objects.find_all(
obj_id=dropped_obj.id,
children=True,
include_self=False
)
for child_obj in children_objects:
child_obj.stop()
self.objects.unregister(child_obj)
dropped_obj.stop()
self.objects.unregister(dropped_obj)
@staticmethod
def _find_local(ps=None):
"""
Tries to find all mysqld processes
:param ps: [] of str, used for debugging our parsing logic - should be None most of the time
:return: [] of {} MySQL object definitions
"""
# get ps info
try:
# set ps output to passed param or call subp
ps, _ = (ps, None) if ps is not None else subp.call(PS_CMD)
context.log.debug('ps mysqld output: %s' % ps)
except Exception as e:
# log error
exception_name = e.__class__.__name__
context.log.debug(
'failed to find running mysqld via "%s" due to %s' % (
PS_CMD, exception_name
)
)
context.log.debug('additional info:', exc_info=True)
# If there is a root_object defined, log an event to send to the
# cloud.
if context.objects.root_object:
context.objects.root_object.eventd.event(
level=INFO,
message='no mysqld processes found'
)
# break processing returning a fault-tolerant empty list
return []
if not any('mysqld' in line for line in ps):
context.log.info('no mysqld processes found')
# break processing returning a fault-tolerant empty list
return []
# collect all info about processes
masters = {}
try:
for line in ps:
parsed = ps_parser(line)
# if not parsed - go to the next line
if parsed is None:
continue
pid, ppid, cmd = parsed # unpack values
# match master process
if cmd.split(' ', 1)[0].endswith('mysqld'):
if not launch_method_supported("mysql", ppid):
continue
try:
conf_path = master_parser(cmd)
except Exception as e:
context.log.error('failed to find conf_path for %s' % cmd)
context.log.debug('additional info:', exc_info=True)
else:
# calculate local_id
local_string_id = '%s_%s' % (cmd, conf_path)
local_id = hashlib.sha256(local_string_id.encode('utf-8')).hexdigest()
if pid not in masters:
masters[pid] = {}
masters[pid].update({
'cmd': cmd.strip(),
'conf_path': conf_path,
'pid': pid,
'local_id': local_id
})
except Exception as e:
# log error
exception_name = e.__class__.__name__
context.log.error('failed to parse ps results due to %s' % exception_name)
context.log.debug('additional info:', exc_info=True)
# format results
results = []
for payload in masters.values():
# only add payloads that have all the keys
if 'cmd' in payload and 'conf_path' in payload and 'pid' in payload and 'local_id' in payload:
results.append(payload)
else:
context.log.debug('MySQL "_find_all()" found an incomplete entity %s' % payload)
return results
@staticmethod
def _find_remote():
"""
:return: [] of {} MySQL object definition for remote mysqld process
"""
results = []
try:
cmd = "/usr/sbin/mysqld"
conf_path = "/etc/mysql/my.cnf"
# calculate local_id
local_string_id = '%s_%s' % (cmd, conf_path)
local_id = hashlib.sha256(local_string_id.encode('utf-8')).hexdigest()
results.append({
'cmd': 'unknown',
'conf_path': 'unknown',
'pid': 'unknown',
'local_id': local_id
})
except Exception as e:
# log error
exception_name = e.__class__.__name__
context.log.error('failed to parse remote mysql results due to %s' % exception_name)
context.log.debug('additional info:', exc_info=True)
return results