diff --git a/tools/pypmmn/.gitignore b/tools/pypmmn/.gitignore new file mode 100644 index 00000000..0b7a733f --- /dev/null +++ b/tools/pypmmn/.gitignore @@ -0,0 +1,5 @@ +env +build +MANIFEST +dist +plugins diff --git a/tools/pypmmn/README.rst b/tools/pypmmn/README.rst new file mode 100644 index 00000000..083c24a9 --- /dev/null +++ b/tools/pypmmn/README.rst @@ -0,0 +1,68 @@ +PyPMMN +====== + +PyPMMN is a pure python port of pmmn_. One small change: Instead of using the +current working dir as ``plugins`` folder, it will look for a *subdirectory* +called ``plugins`` in the current working folder. This value can be overridden +by a command-line parameter! + +Requirements +============ + +PyPMMN does not have any requirements other than the python standard library. +For compatibility, it's targeted for Python 2.4 and up. + +Known Issues +============ + +* The stdin mode does not work correctly. Consider using the original pmmn_ + instead. +* It's not multithreaded. Only one connection is handled at a time. But given + the nature of munin, this should not be an issue. + +Installation +============ + +The python way +-------------- + +Download the folder and run:: + + python setup.py install + +This will install ``pypmmn.py`` into your system's ``bin`` folder. Commonly, +this is ``/usr/local/bin``. + +And of course, you can use virtual environments too! + +Manually +-------- + +Download the folder and copy both files ``pypmmn/pypmmn.py`` and +``pypmmn/daemon.py`` to a location of your choice and ensure ``pypmmn.py`` is +executable. + +Usage +===== + +All command-line parameters are documented. Simply run:: + + pypmmn.py --help + +to get more information. + +Example:: + + pypmmn.py -l /path/to/log-dir -d /path/to/plugins -p 4949 + +Daemon mode +----------- + +In daemon mode, it's very helpful to specify a log folder. It gives you a +means to inspect what's happening. In the case you specified a log folder, +pypmmn will also create a file called ``pypmmn.pid`` containing the PID of the +daemon for convenience. + + +.. _pmmn: http://blog.pwkf.org/post/2008/11/04/A-Poor-Man-s-Munin-Node-to-Monitor-Hostile-UNIX-Servers + diff --git a/tools/pypmmn/pypmmn/__init__.py b/tools/pypmmn/pypmmn/__init__.py new file mode 100644 index 00000000..e69de29b diff --git a/tools/pypmmn/pypmmn/daemon.py b/tools/pypmmn/pypmmn/daemon.py new file mode 100644 index 00000000..f966072a --- /dev/null +++ b/tools/pypmmn/pypmmn/daemon.py @@ -0,0 +1,210 @@ +## {{{ http://code.activestate.com/recipes/278731/ (r6) +"""Disk And Execution MONitor (Daemon) + +Configurable daemon behaviors: + + 1.) The current working directory set to the "/" directory. + 2.) The current file creation mode mask set to 0. + 3.) Close all open files (1024). + 4.) Redirect standard I/O streams to "/dev/null". + +A failed call to fork() now raises an exception. + +References: + 1) Advanced Programming in the Unix Environment: W. Richard Stevens + 2) Unix Programming Frequently Asked Questions: + http://www.erlenstar.demon.co.uk/unix/faq_toc.html +""" + +__author__ = "Chad J. Schroeder" +__copyright__ = "Copyright (C) 2005 Chad J. Schroeder" + +__revision__ = "$Id$" +__version__ = "0.2" + +# Standard Python modules. +import os # Miscellaneous OS interfaces. +import sys # System-specific parameters and functions. + +# Default daemon parameters. +# File mode creation mask of the daemon. +UMASK = 0 + +# Default working directory for the daemon. +WORKDIR = "/" + +# Default maximum for the number of available file descriptors. +MAXFD = 1024 + +# The standard I/O file descriptors are redirected to /dev/null by default. +if (hasattr(os, "devnull")): + REDIRECT_TO = os.devnull +else: + REDIRECT_TO = "/dev/null" + +def createDaemon(): + """Detach a process from the controlling terminal and run it in the + background as a daemon. + """ + + try: + # Fork a child process so the parent can exit. This returns control to + # the command-line or shell. It also guarantees that the child will not + # be a process group leader, since the child receives a new process ID + # and inherits the parent's process group ID. This step is required + # to insure that the next call to os.setsid is successful. + pid = os.fork() + except OSError, e: + raise Exception, "%s [%d]" % (e.strerror, e.errno) + + if (pid == 0): # The first child. + # To become the session leader of this new session and the process group + # leader of the new process group, we call os.setsid(). The process is + # also guaranteed not to have a controlling terminal. + os.setsid() + + # Is ignoring SIGHUP necessary? + # + # It's often suggested that the SIGHUP signal should be ignored before + # the second fork to avoid premature termination of the process. The + # reason is that when the first child terminates, all processes, e.g. + # the second child, in the orphaned group will be sent a SIGHUP. + # + # "However, as part of the session management system, there are exactly + # two cases where SIGHUP is sent on the death of a process: + # + # 1) When the process that dies is the session leader of a session that + # is attached to a terminal device, SIGHUP is sent to all processes + # in the foreground process group of that terminal device. + # 2) When the death of a process causes a process group to become + # orphaned, and one or more processes in the orphaned group are + # stopped, then SIGHUP and SIGCONT are sent to all members of the + # orphaned group." [2] + # + # The first case can be ignored since the child is guaranteed not to have + # a controlling terminal. The second case isn't so easy to dismiss. + # The process group is orphaned when the first child terminates and + # POSIX.1 requires that every STOPPED process in an orphaned process + # group be sent a SIGHUP signal followed by a SIGCONT signal. Since the + # second child is not STOPPED though, we can safely forego ignoring the + # SIGHUP signal. In any case, there are no ill-effects if it is ignored. + # + # import signal # Set handlers for asynchronous events. + # signal.signal(signal.SIGHUP, signal.SIG_IGN) + + try: + # Fork a second child and exit immediately to prevent zombies. This + # causes the second child process to be orphaned, making the init + # process responsible for its cleanup. And, since the first child is + # a session leader without a controlling terminal, it's possible for + # it to acquire one by opening a terminal in the future (System V- + # based systems). This second fork guarantees that the child is no + # longer a session leader, preventing the daemon from ever acquiring + # a controlling terminal. + pid = os.fork() # Fork a second child. + except OSError, e: + raise Exception, "%s [%d]" % (e.strerror, e.errno) + + if (pid == 0): # The second child. + # Since the current working directory may be a mounted filesystem, we + # avoid the issue of not being able to unmount the filesystem at + # shutdown time by changing it to the root directory. + os.chdir(WORKDIR) + # We probably don't want the file mode creation mask inherited from + # the parent, so we give the child complete control over permissions. + os.umask(UMASK) + else: + # exit() or _exit()? See below. + os._exit(0) # Exit parent (the first child) of the second child. + else: + # exit() or _exit()? + # _exit is like exit(), but it doesn't call any functions registered + # with atexit (and on_exit) or any registered signal handlers. It also + # closes any open file descriptors. Using exit() may cause all stdio + # streams to be flushed twice and any temporary files may be unexpectedly + # removed. It's therefore recommended that child branches of a fork() + # and the parent branch(es) of a daemon use _exit(). + os._exit(0) # Exit parent of the first child. + + # Close all open file descriptors. This prevents the child from keeping + # open any file descriptors inherited from the parent. There is a variety + # of methods to accomplish this task. Three are listed below. + # + # Try the system configuration variable, SC_OPEN_MAX, to obtain the maximum + # number of open file descriptors to close. If it doesn't exists, use + # the default value (configurable). + # + # try: + # maxfd = os.sysconf("SC_OPEN_MAX") + # except (AttributeError, ValueError): + # maxfd = MAXFD + # + # OR + # + # if (os.sysconf_names.has_key("SC_OPEN_MAX")): + # maxfd = os.sysconf("SC_OPEN_MAX") + # else: + # maxfd = MAXFD + # + # OR + # + # Use the getrlimit method to retrieve the maximum file descriptor number + # that can be opened by this process. If there is not limit on the + # resource, use the default value. + # + import resource # Resource usage information. + maxfd = resource.getrlimit(resource.RLIMIT_NOFILE)[1] + if (maxfd == resource.RLIM_INFINITY): + maxfd = MAXFD + + # Iterate through and close all file descriptors. + for fd in range(0, maxfd): + try: + os.close(fd) + except OSError: # ERROR, fd wasn't open to begin with (ignored) + pass + + # Redirect the standard I/O file descriptors to the specified file. Since + # the daemon has no controlling terminal, most daemons redirect stdin, + # stdout, and stderr to /dev/null. This is done to prevent side-effects + # from reads and writes to the standard I/O file descriptors. + + # This call to open is guaranteed to return the lowest file descriptor, + # which will be 0 (stdin), since it was closed above. + os.open(REDIRECT_TO, os.O_RDWR) # standard input (0) + + # Duplicate standard input to standard output and standard error. + os.dup2(0, 1) # standard output (1) + os.dup2(0, 2) # standard error (2) + + return(0) + +if __name__ == "__main__": + + retCode = createDaemon() + + # The code, as is, will create a new file in the root directory, when + # executed with superuser privileges. The file will contain the following + # daemon related process parameters: return code, process ID, parent + # process group ID, session ID, user ID, effective user ID, real group ID, + # and the effective group ID. Notice the relationship between the daemon's + # process ID, process group ID, and its parent's process ID. + + procParams = """ + return code = %s + process ID = %s + parent process ID = %s + process group ID = %s + session ID = %s + user ID = %s + effective user ID = %s + real group ID = %s + effective group ID = %s + """ % (retCode, os.getpid(), os.getppid(), os.getpgrp(), os.getsid(0), + os.getuid(), os.geteuid(), os.getgid(), os.getegid()) + + open("createDaemon.log", "w").write(procParams + "\n") + + sys.exit(retCode) +## end of http://code.activestate.com/recipes/278731/ }}} + diff --git a/tools/pypmmn/pypmmn/pypmmn.py b/tools/pypmmn/pypmmn/pypmmn.py new file mode 100644 index 00000000..4d38dc5e --- /dev/null +++ b/tools/pypmmn/pypmmn/pypmmn.py @@ -0,0 +1,411 @@ +#!/usr/bin/python +""" +A very simple munin-node written in pure python (no external libraries +required) +""" +from datetime import datetime +from logging.handlers import RotatingFileHandler +from optparse import OptionParser +from os import listdir, access, X_OK, getpid +from os.path import join, isdir, abspath, dirname, exists +from subprocess import Popen, PIPE +from time import sleep +import logging +import socket + +import sys + +LOG = logging.getLogger(__name__) +LOG_FORMAT = '%(asctime)s - %(name)s - %(levelname)s - %(message)s' +SESSION_TIMEOUT = 10 # Amount of seconds until an unused session is closed + +from daemon import createDaemon + + +__version__ = '1.0b1' + + +class CmdHandler(object): + """ + This handler defines the protocol between munin and this munin node. + Each method starting with ``do_`` responds to the corresponding munin + command. + """ + + def __init__(self, get_fun, put_fun, options): + """ + Constructor + + :param get_fun: The function used to receive a message from munin + :param put_fun: The function used to send a message back to munin + :param options: The command-line options object + """ + self.get_fun = get_fun + self.put_fun = put_fun + self.options = options + + def do_version(self, arg): + """ + Prints the version of this instance. + """ + LOG.debug('Command "version" executed with args: %r' % arg) + self.put_fun('# munin node at %s\n' % ( + self.options.host, + )) + + def do_nodes(self, arg): + """ + Prints this hostname + """ + LOG.debug('Command "nodes" executed with args: %r' % arg) + self.put_fun('%s\n' % self.options.host) + self.put_fun('.\n') + + def do_quit(self, arg): + """ + Stops this process + """ + LOG.debug('Command "quit" executed with args: %r' % arg) + sys.exit(0) + + def do_list(self, arg): + """ + Print a list of plugins + """ + LOG.debug('Command "list" executed with args: %r' % arg) + try: + LOG.debug('Listing files inside %s' % self.options.plugin_dir) + for filename in listdir(self.options.plugin_dir): + if not access(join(self.options.plugin_dir, filename), X_OK): + LOG.warning('Non-executable plugin %s found!' % filename) + continue + LOG.debug('Found plugin: %s' % filename) + self.put_fun("%s " % filename) + except OSError, exc: + self.put_fun("# ERROR: %s" % exc) + self.put_fun("\n") + + def _caf(self, plugin, cmd): + """ + handler for ``config``, ``alert`` and ``fetch`` + Calls the plugin with ``cmd`` as only argument. + + :param plugin: The plugin name + :param cmd: The command which is to passed to the plugin + """ + plugin_filename = join(self.options.plugin_dir, plugin) + + # Sanity checks + if isdir(plugin_filename) or not access(plugin_filename, X_OK): + msg = "# Unknown plugin [%s] for %s" % (plugin, cmd) + LOG.warning(msg) + self.put_fun(msg) + return + + # for 'fetch' we don't need to pass a command to the plugin + if cmd == 'fetch': + plugin_arg = '' + else: + plugin_arg = cmd + + try: + cmd = [plugin_filename, plugin_arg] + LOG.debug('Executing %r' % cmd) + output = Popen(cmd, stdout=PIPE).communicate()[0] + except OSError, exc: + LOG.exception() + self.put_fun("# ERROR: %s\n" % exc) + return + self.put_fun(output) + self.put_fun('.\n') + + def do_alert(self, arg): + """ + Handle command "alert" + """ + LOG.debug('Command "alert" executed with args: %r' % arg) + self._caf(arg, 'alert') + + def do_fetch(self, arg): + """ + Handles command "fetch" + """ + LOG.debug('Command "fetch" executed with args: %r' % arg) + self._caf(arg, 'fetch') + + def do_config(self, arg): + """ + Handles command "config" + """ + LOG.debug('Command "config" executed with args: %r' % arg) + self._caf(arg, 'config') + + def do_cap(self, arg): + """ + Handles command "cap" + """ + LOG.debug('Command "cap" executed with args: %r' % arg) + self.put_fun("cap ") + if self.options.spoolfetch_dir: + self.put_fun("spool") + else: + LOG.debug('No spoolfetch_dir specified. Result spooling disabled') + + self.put_fun("\n") + + def do_spoolfetch(self, arg): + """ + Handles command "spoolfetch" + """ + LOG.debug('Command "spellfetch" executed with args: %r' % arg) + output = Popen(['%s/spoolfetch_%s' % (self.options.spoolfetch_dir, + self.options.host), + arg]).communicate()[0] + self.put_fun(output) + self.put_fun('.\n') + + # aliases + do_exit = do_quit + + def handle_input(self, line): + """ + Handles one input line and sends any result back using ``put_fun`` + """ + line = line.strip() + line = line.split(' ') + cmd = line[0] + if len(line) == 1: + arg = '' + elif len(line) == 2: + arg = line[1] + else: + self.put_fun('# Invalid input: %s\n' % line) + return + + if not cmd: + return + + func = getattr(self, 'do_%s' % cmd, None) + if not func: + # Give the client a list of supported commands. + commands = [_[3:] for _ in dir(self) if _.startswith('do_')] + self.put_fun("# Unknown command. Supported commands: %s\n" % ( + commands)) + return + + func(arg) + + def is_timed_out(self): + return (datetime.now() - self._last_command).seconds > SESSION_TIMEOUT + + def reset_time(self): + self._last_command = datetime.now() + + +def usage(option, opt, value, parser): + """ + Prints the command usage and exits + """ + parser.print_help() + sys.exit(0) + + +def get_options(): + """ + Parses command-line arguments. + """ + parser = OptionParser(add_help_option=False) + parser.add_option('-p', '--port', dest='port', + default=None, + help='TCP Port to listen on. (If not specified, use stdin/stdout)') + parser.add_option('-d', '--plugin-dir', dest='plugin_dir', + default='plugins', + help=('The directory containing the munin-plugins.' + ' Default: /plugins')) + parser.add_option('-h', '--host', dest='host', + help=('The hostname which will be reported in the plugins.' + ' Default: %s' % socket.gethostname()), + default=socket.gethostname()) + parser.add_option('-n', '--no-daemon', dest='no_daemon', + default=False, + action='store_true', + help='Run in foreground. Do not daemonize. ' + 'Will also enable debug logging to stdout.') + parser.add_option('-l', '--log-dir', dest='log_dir', + default=None, + help='The log folder. Default: disabled') + parser.add_option('-s', '--spoolfech-dir', dest='spoolfetch_dir', + default=None, + help='The spoolfetch folder. Default: disabled') + parser.add_option('--help', action='callback', callback=usage, + help='Shows this help') + + options, args = parser.parse_args() + + # ensure we are using absolute paths (for daemonizing) + if options.log_dir: + options.log_dir = abspath(options.log_dir) + + if options.spoolfetch_dir: + options.spoolfetch_dir = abspath(options.spoolfetch_dir) + + if options.plugin_dir: + options.plugin_dir = abspath(options.plugin_dir) + + return (options, args) + + +def process_stdin(options): + """ + Process commands by reading from stdin + """ + rfhandler = RotatingFileHandler( + join(abspath(dirname(__file__)), 'log', 'pypmmn.log'), + maxBytes=100 * 1024, + backupCount=5 + ) + rfhandler.setFormatter(logging.Formatter(LOG_FORMAT)) + logging.getLogger().addHandler(rfhandler) + handler = CmdHandler(sys.stdin.read, sys.stdout.write, options) + handler.do_version(None) + LOG.info('STDIN handler opened') + while True: + data = sys.stdin.readline().strip() + if not data: + return + handler.handle_input(data) + + +def process_socket(options): + """ + Process socket connections. + + .. note:: + + This is not a multithreaded process. So only one connection can be + handled at any given time. But given the nature of munin, this is Good + Enough. + """ + + retcode = 0 + if options.no_daemon: + # set up on-screen-logging + console_handler = logging.StreamHandler(sys.stdout) + console_handler.setFormatter(logging.Formatter(LOG_FORMAT)) + logging.getLogger().addHandler(console_handler) + else: + # fork fork + retcode = createDaemon() + + # set up a rotating file log + rfhandler = RotatingFileHandler( + join(options.log_dir, 'daemon.log'), + maxBytes=100 * 1024, + backupCount=5 + ) + rfhandler.setFormatter(logging.Formatter(LOG_FORMAT)) + logging.getLogger().addHandler(rfhandler) + + # write down some house-keeping information + LOG.info('New process PID: %d' % getpid()) + pidfile = open(join(options.log_dir, 'pypmmn.pid'), 'w') + pidfile.write(str(getpid())) + pidfile.close() + LOG.info('PID file created in %s' % join(options.log_dir, + 'pypmmn.pid')) + + LOG.info('Socket handler started.') + + host = '' # listens on all addresses TODO: make this configurable + port = int(options.port) + + s = socket.socket(socket.AF_INET, socket.SOCK_STREAM) + s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1) + s.bind((host, port)) + s.listen(1) + + LOG.info('Listening on host %r, port %r' % (host, port)) + + conn, addr = s.accept() + handler = CmdHandler(conn.recv, conn.send, options) + handler.do_version(None) + handler.reset_time() + + LOG.info("Accepting incoming connection from %s" % (addr, )) + while True: + data = conn.recv(1024) + if not data.strip(): + sleep(1) + if handler.is_timed_out(): + LOG.info('Session timeout.') + conn.shutdown(socket.SHUT_RDWR) + conn.close() + + LOG.info('Listening on host %r, port %r' % (host, port)) + + conn, addr = s.accept() + handler.reset_time() + handler.get_fun = conn.recv + handler.put_fun = conn.send + handler.do_version(None) + + LOG.info("Accepting incoming connection from %s" % (addr, )) + try: + data = conn.recv(1024) + except socket.error, exc: + LOG.warning("Socket error. Reinitialising.: %s" % exc) + conn, addr = s.accept() + handler.reset_time() + handler.get_fun = conn.recv + handler.put_fun = conn.send + handler.do_version(None) + + LOG.info("Accepting incoming connection from %s" % (addr, )) + + if data.strip() == 'quit': + LOG.info('Client requested session end. Closing connection.') + conn.shutdown(socket.SHUT_RDWR) + conn.close() + + LOG.info('Listening on host %r, port %r' % (host, port)) + + conn, addr = s.accept() + handler.reset_time() + handler.get_fun = conn.recv + handler.put_fun = conn.send + handler.do_version(None) + + LOG.info("Accepting incoming connection from %s" % (addr, )) + + continue + + handler.handle_input(data) + + sys.exit(retcode) + + +def main(): + """ + The main entry point of the application + """ + options, args = get_options() + + # Handle logging as early as possible. + if options.log_dir: + if not exists(options.log_dir): + raise IOError('[Errno 2] No such file or directory: %r' % ( + options.log_dir)) + # set up logging if requested + root_logger = logging.getLogger() + root_logger.setLevel(logging.NOTSET) # TODO: Make configurable + + # Start either the "stdin" interface, or the socked daemon. Depending on + # whether a port was given on startup or not. + if not options.port: + process_stdin(options) + else: + process_socket(options) + + +if __name__ == '__main__': + main() diff --git a/tools/pypmmn/setup.py b/tools/pypmmn/setup.py new file mode 100644 index 00000000..0d3ac57d --- /dev/null +++ b/tools/pypmmn/setup.py @@ -0,0 +1,22 @@ +from distutils.core import setup +from pypmmn.pypmmn import __version__ + +PACKAGE = "pypmmn" +NAME = "pypmmn" +DESCRIPTION = "Python port of the 'Poor man's munin-node'" +AUTHOR = "Michel Albert" +AUTHOR_EMAIL = "michel@albert.lu" + +setup( + name=NAME, + version=__version__, + description=DESCRIPTION, + long_description=open("README.rst").read(), + author=AUTHOR, + author_email=AUTHOR_EMAIL, + license="BSD", + url='https://github.com/exhuma/munin-contrib/tree/master/tools/pypmmn', + packages=['pypmmn'], + scripts=['pypmmn/pypmmn.py'], +) +