#!/usr/bin/env python3 # MonitoringInstance.py - Class implementing a PVC monitor in pvchealthd # Part of the Parallel Virtual Cluster (PVC) system # # Copyright (C) 2018-2022 Joshua M. Boniface # # This program is free software: you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by # the Free Software Foundation, version 3. # # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # # You should have received a copy of the GNU General Public License # along with this program. If not, see . # ############################################################################### import concurrent.futures import time import importlib.util from os import walk from datetime import datetime from json import dumps from apscheduler.schedulers.background import BackgroundScheduler class PluginError(Exception): """ An exception that results from a plugin failing setup """ pass class PluginResult(object): def __init__(self, zkhandler, config, logger, this_node, plugin_name): self.zkhandler = zkhandler self.config = config self.logger = logger self.this_node = this_node self.plugin_name = plugin_name self.current_time = int(time.time()) self.health_delta = 0 self.message = "N/A" self.data = {} self.runtime = "0.00" def set_health_delta(self, new_delta): self.health_delta = new_delta def set_message(self, new_message): self.message = new_message def set_data(self, new_data): self.data = new_data def set_runtime(self, new_runtime): self.runtime = new_runtime def to_zookeeper(self): self.zkhandler.write( [ ( ( "node.monitoring.data", self.this_node.name, "monitoring_plugin.name", self.plugin_name, ), self.plugin_name, ), ( ( "node.monitoring.data", self.this_node.name, "monitoring_plugin.last_run", self.plugin_name, ), self.current_time, ), ( ( "node.monitoring.data", self.this_node.name, "monitoring_plugin.health_delta", self.plugin_name, ), self.health_delta, ), ( ( "node.monitoring.data", self.this_node.name, "monitoring_plugin.message", self.plugin_name, ), self.message, ), ( ( "node.monitoring.data", self.this_node.name, "monitoring_plugin.data", self.plugin_name, ), dumps(self.data), ), ( ( "node.monitoring.data", self.this_node.name, "monitoring_plugin.runtime", self.plugin_name, ), self.runtime, ), ] ) class MonitoringPlugin(object): def __init__(self, zkhandler, config, logger, this_node, plugin_name): self.zkhandler = zkhandler self.config = config self.logger = logger self.this_node = this_node self.plugin_name = plugin_name self.plugin_result = PluginResult( self.zkhandler, self.config, self.logger, self.this_node, self.plugin_name, ) def __str__(self): return self.plugin_name # # Helper functions; exposed to child MonitoringPluginScript instances # def log(self, message, state="d"): """ Log a message to the PVC logger instance using the plugin name as a prefix Takes "state" values as defined by the PVC logger instance, defaulting to debug: "d": debug "i": informational "t": tick/keepalive "w": warning "e": error """ if state == "d" and not self.config["debug"]: return self.logger.out(message, state=state, prefix=self.plugin_name) # # Primary class functions; implemented by the individual plugins # def setup(self): """ setup(): Perform setup of the plugin; run once during daemon startup This step is optional and should be used sparingly. If you wish for the plugin to not load in certain conditions, do any checks here and return a non-None failure message to indicate the error. """ pass def run(self, coordinator_state=None): """ run(): Run the plugin, returning a PluginResult object The {coordinator_state} can be used to check if this is a "primary" coordinator, "secondary" coordinator, or "client" (non-coordinator) """ return self.plugin_result def cleanup(self): """ cleanup(): Clean up after the plugin; run once during daemon shutdown OPTIONAL """ pass class MonitoringInstance(object): def __init__(self, zkhandler, config, logger, this_node): self.zkhandler = zkhandler self.config = config self.logger = logger self.this_node = this_node # Get a list of plugins from the plugin_directory plugin_files = next(walk(self.config["plugin_directory"]), (None, None, []))[ 2 ] # [] if no file self.all_plugins = list() self.all_plugin_names = list() successful_plugins = 0 # Load each plugin file into the all_plugins list for plugin_file in sorted(plugin_files): try: self.logger.out( f"Loading monitoring plugin from {self.config['plugin_directory']}/{plugin_file}", state="i", ) loader = importlib.machinery.SourceFileLoader( "plugin_script", f"{self.config['plugin_directory']}/{plugin_file}" ) spec = importlib.util.spec_from_loader(loader.name, loader) plugin_script = importlib.util.module_from_spec(spec) spec.loader.exec_module(plugin_script) plugin = plugin_script.MonitoringPluginScript( self.zkhandler, self.config, self.logger, self.this_node, plugin_script.PLUGIN_NAME, ) failed_setup = plugin.setup() if failed_setup is not None: raise PluginError(f"{failed_setup}") # Create plugin key self.zkhandler.write( [ ( ( "node.monitoring.data", self.this_node.name, "monitoring_plugin.name", plugin.plugin_name, ), plugin.plugin_name, ), ( ( "node.monitoring.data", self.this_node.name, "monitoring_plugin.last_run", plugin.plugin_name, ), "0", ), ( ( "node.monitoring.data", self.this_node.name, "monitoring_plugin.health_delta", plugin.plugin_name, ), "0", ), ( ( "node.monitoring.data", self.this_node.name, "monitoring_plugin.message", plugin.plugin_name, ), "Initializing", ), ( ( "node.monitoring.data", self.this_node.name, "monitoring_plugin.data", plugin.plugin_name, ), dumps({}), ), ( ( "node.monitoring.data", self.this_node.name, "monitoring_plugin.runtime", plugin.plugin_name, ), "0.00", ), ] ) self.all_plugins.append(plugin) self.all_plugin_names.append(plugin.plugin_name) successful_plugins += 1 self.logger.out( f"Successfully loaded monitoring plugin '{plugin.plugin_name}'", state="o", ) except Exception as e: self.logger.out( f"Failed to load monitoring plugin: {e}", state="w", ) self.zkhandler.write( [ ( ("node.monitoring.plugins", self.this_node.name), " ".join(self.all_plugin_names), ), ] ) if successful_plugins < 1: self.logger.out( "No plugins loaded; pvchealthd going into noop loop. Incorrect plugin directory? Fix and restart pvchealthd.", state="e", ) return self.logger.out( f'{self.logger.fmt_cyan}Plugin list:{self.logger.fmt_end} {" ".join(self.all_plugin_names)}', state="s", ) # Clean up any old plugin data for which a plugin file no longer exists plugins_data = self.zkhandler.children( ("node.monitoring.data", self.this_node.name) ) if plugins_data is not None: for plugin_key in plugins_data: if plugin_key not in self.all_plugin_names: self.zkhandler.delete( ( "node.monitoring.data", self.this_node.name, "monitoring_plugin", plugin_key, ) ) self.run_plugins() self.start_check_timer() def __del__(self): self.shutdown() def shutdown(self): self.stop_check_timer() self.run_cleanups() return def start_check_timer(self): check_interval = self.config["monitoring_interval"] self.logger.out( f"Starting monitoring check timer ({check_interval} second interval)", state="s", ) self.check_timer = BackgroundScheduler() self.check_timer.add_job( self.run_plugins, trigger="interval", seconds=check_interval, ) self.check_timer.start() def stop_check_timer(self): try: self.check_timer.shutdown() self.logger.out("Stopping monitoring check timer", state="s") except Exception: self.logger.out("Failed to stop monitoring check timer", state="w") def run_plugin(self, plugin): time_start = datetime.now() try: result = plugin.run(coordinator_state=self.this_node.coordinator_state) except Exception as e: self.logger.out( f"Monitoring plugin {plugin.plugin_name} failed: {type(e).__name__}: {e}", state="e", ) # Whatever it had, we try to return return plugin.plugin_result time_end = datetime.now() time_delta = time_end - time_start runtime = "{:0.02f}".format(time_delta.total_seconds()) result.set_runtime(runtime) result.to_zookeeper() return result def run_plugins(self): if self.this_node.coordinator_state == "primary": cst_colour = self.logger.fmt_green elif self.this_node.coordinator_state == "secondary": cst_colour = self.logger.fmt_blue else: cst_colour = self.logger.fmt_cyan active_coordinator_state = self.this_node.coordinator_state runtime_start = datetime.now() self.logger.out( "Starting monitoring healthcheck run", state="t", ) total_health = 100 plugin_results = list() with concurrent.futures.ThreadPoolExecutor(max_workers=99) as executor: to_future_plugin_results = { executor.submit(self.run_plugin, plugin): plugin for plugin in self.all_plugins } for future in concurrent.futures.as_completed(to_future_plugin_results): plugin_results.append(future.result()) for result in sorted(plugin_results, key=lambda x: x.plugin_name): if ( self.config["log_keepalives"] and self.config["log_keepalive_plugin_details"] ): self.logger.out( result.message + f" [-{result.health_delta}]", state="t", prefix=f"{result.plugin_name} ({result.runtime}s)", ) total_health -= result.health_delta if total_health < 0: total_health = 0 self.zkhandler.write( [ ( ("node.monitoring.health", self.this_node.name), total_health, ), ] ) runtime_end = datetime.now() runtime_delta = runtime_end - runtime_start runtime = "{:0.02f}".format(runtime_delta.total_seconds()) time.sleep(0.2) if isinstance(self.this_node.health, int): if self.this_node.health > 90: health_colour = self.logger.fmt_green elif self.this_node.health > 50: health_colour = self.logger.fmt_yellow else: health_colour = self.logger.fmt_red health_text = str(self.this_node.health) + "%" else: health_colour = self.logger.fmt_blue health_text = "N/A" self.logger.out( "{start_colour}{hostname} healthcheck @ {starttime}{nofmt} [{cst_colour}{costate}{nofmt}] result is {health_colour}{health}{nofmt} in {runtime} seconds".format( start_colour=self.logger.fmt_purple, cst_colour=self.logger.fmt_bold + cst_colour, health_colour=health_colour, nofmt=self.logger.fmt_end, hostname=self.config["node_hostname"], starttime=runtime_start, costate=active_coordinator_state, health=health_text, runtime=runtime, ), state="t", ) def run_cleanup(self, plugin): return plugin.cleanup() def run_cleanups(self): with concurrent.futures.ThreadPoolExecutor(max_workers=99) as executor: to_future_plugin_results = { executor.submit(self.run_cleanup, plugin): plugin for plugin in self.all_plugins } for future in concurrent.futures.as_completed(to_future_plugin_results): # This doesn't do anything, just lets us wait for them all to complete pass # Set the node health to None as no previous checks are now valid self.zkhandler.write( [ ( ("node.monitoring.health", self.this_node.name), None, ), ] )