#!/usr/bin/env python
"""
USAGE

    dell_changeme [config] [autoconfig]

    Copy script to two files: dell_fans and dell_temps.
    Example: cat dell_changeme | tee dell_fans > dell_temps

DESCRIPTION

    A Munin plugin to graph the fan speeds and chassis temperatures of Dell
    hardware. Requires Dell's OpenManage software, specifically omreport. OMSA
    services must be started prior to plugins use. Script expects omreport to
    be in /usr/sbin/, you may need to add a symlink.

    omreport accesses the proc filesystem and as such this plugin must be ran
    as root. Alternatively, you could modify script to use sudoers, or setuid.

    To run script as root add the following lines to munin's plugin-conf.d dir.

    [dell*]
    user root
    group root

    Troubleshooting info: http://www.ryanbowlby.com/infotech/munin-plugin-dell/

AUTHOR

    Ryan Bowlby <rbowlby83 yahoo>

LICENSE

    This script is in the public domain, free from copyrights or restrictions.
"""
# Magic markers (optional) - used by munin-node-configure:
#
#%# family=auto
#%# capabilities=autoconf

import sys
import subprocess as sp

class Statistics(object):
    """A base class that runs omreport and prints the filtered results."""

    def __init__(self, command):
        self.command = command.split()
        self.data = sp.Popen(self.command,stdout=sp.PIPE).stdout.readlines()
        self.count = 0
        # Make sure omreport returns at least one sensor block.
        for item in self.data:
            if item.startswith("Probe Name") or item.startswith("Reading"):
                self.count += 1
        if self.count < 2:
            raise ValueError("No output from omreport. Is OMSA running?")

    def print_omreport_results(self):
        """Prints names and values for each sensor."""
        self.count = 0
        for item in self.data:
            if "Reading" in item:
                # Extract variable length integer.
                self.value = float(item.split(":")[1].split()[0])
                print "%s_%s.value %s" % (self.command[-1], self.count, self.value)
                self.count += 1

    def print_config_dynamic(self):
        """Prints Munin config data with "label" values from omreport data."""
        self.name = []
        for item in self.data:
            if "Probe Name" in item:
                self.name.append(item.split(":")[1].replace("RPM","").strip())
        for index, item in enumerate(self.name):
            print "%s_%s.label %s" % (self.command[-1], index, item)


class FanSpeed(Statistics):
    """A subclass that includes the Munin "config" output."""

    def __init__(self, command):
        Statistics.__init__(self, command)

    def print_config(self):
        print "graph_title Dell Fan Speeds"
        print "graph_args --base 1000 -l 0"
        print "graph_vlabel speed (RPM)"
        print "graph_category Chassis"
        print "graph_info This graph shows the speed in RPM of all fans."
        print "graph_period second"
        # Print remaining non-static values.
        self.print_config_dynamic()


class ChassisTemps(Statistics):
    """A subclass that includes the Munin "config" output."""

    def __init__(self, command):
        Statistics.__init__(self, command)

    def print_config(self):
        print "graph_title Dell Temperature Readings"
        print "graph_args --base 1000 -l 0"
        print "graph_vlabel Temp in Degrees Celsius"
        print "graph_category Chassis"
        print "graph_info This graph shows the temperature for all sensors."
        print "graph_period second"
        # Print remaining non-static values.
        self.print_config_dynamic()


if __name__ == '__main__':
    try:
        if "fans" in sys.argv[0]:
            cmd = "/usr/sbin/omreport chassis fans"
            omdata = FanSpeed(cmd)
        elif "temps" in sys.argv[0]:
            cmd = "/usr/sbin/omreport chassis temps"
            omdata = ChassisTemps(cmd)
        else:
            print >> sys.stderr, "Change filename to dell_fans or dell_temps."
            sys.exit(1)
    except (OSError, ValueError), e:
        # omreport returns 0 results if OMSA services aren't started.
        print >> sys.stderr, "Error running '%s', %s" % (cmd, e)
        sys.exit(1)

    # Munin populates sys.argv[1] with "" (an empty argument), let's remove it.
    sys.argv = [x for x in sys.argv if x]

    if len(sys.argv) > 1:
        if sys.argv[1].lower() == "autoconf":
            # omreport ran earlier, since we got this far autoconf is good.
            print "true"
        elif sys.argv[1].lower() == "config":
            omdata.print_config()
    else:
        omdata.print_omreport_results()

