scripts / nagios-plugins

Commit 2349fc1add0c1f5d2b38dafb8d52d3fc473b6abb

Authored by Frederik Lindenaar
1 parent d54130d1

Added support for I2C MCP9808 sensor (closes #4) based on https://github.com/Con… 

…trolEverythingCommunity/MCP9808/blob/master/Python/MCP9808.py
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Showing 1 changed file with 86 additions and 20 deletions
plugins/check_temperature
  View file @2349fc1
... ... @@ -2,10 +2,10 @@
2 2 #
3 3 # check_temperature - Nagios temperature check for DS18B20 sensor on RaspberryPi
4 4 #
5   -# Version 1.1, latest version, documentation and bugtracker available at:
  5 +# Version 1.2, latest version, documentation and bugtracker available at:
6 6 # https://gitlab.lindenaar.net/scripts/nagios-plugins
7 7 #
8   -# Copyright (c) 2017 Frederik Lindenaar
  8 +# Copyright (c) 2017 - 2019 Frederik Lindenaar
9 9 #
10 10 # This script is free software: you can redistribute and/or modify it under the
11 11 # terms of version 3 of the GNU General Public License as published by the Free
... ... @@ -27,15 +27,21 @@ from argparse import ArgumentParser as StandardArgumentParser, FileType, \
27 27 import logging
28 28  
29 29 # Constants (no need to change but allows for easy customization)
30   -VERSION="1.1"
  30 +VERSION="1.2"
31 31 PROG_NAME=splitext(basename(__file__))[0]
32 32 PROG_VERSION=PROG_NAME + ' ' + VERSION
33   -SENSOR_SCALE=1000
  33 +
  34 +CPU_SENSOR_DEV = '/sys/class/thermal/thermal_zone0/temp'
  35 +I2C_MCP9808_CONFIG_ADDR=0x1
  36 +I2C_MCP9808_CONFIG = [ 0x00, 0x00 ] # continuous conversion (power-up default)
  37 +I2C_MCP9808_PRECISION_ADDR=0x08
  38 +I2C_MCP9808_PRECISION=3 # 0=0.5, 1=0.25, 2=0.125, 3=0.0625 degr. C
  39 +I2C_MCP9808_TEMP_ADDR=0x05
34 40 W1_SENSOR_DEV_DIR = '/sys/bus/w1/devices/'
35 41 W1_SENSOR_DEV_PREFIX = '28-'
36 42 W1_SENSOR_DEV_SUFFIX = '/w1_slave'
37 43 W1_SENSOR_READ_RETRIES=10
38   -CPU_SENSOR_DEV = '/sys/class/thermal/thermal_zone0/temp'
  44 +W1_SENSOR_SCALE=1000
39 45  
40 46 LOG_FORMAT='%(levelname)s - %(message)s'
41 47 LOG_FORMAT_FILE='%(asctime)s - ' + LOG_FORMAT
... ... @@ -81,15 +87,15 @@ class SetLogFile(StoreAction):
81 87  
82 88 ###############################################################################
83 89  
84   -def convert_celcius(temp_read):
  90 +def convert_celcius(temp_read, scale = 1):
85 91 """Converts raw temperature sensore value to degrees Celcius"""
86   - return float(temp_read) / float(SENSOR_SCALE)
  92 + return float(temp_read) / float(scale)
87 93 CONVERT_CELCIUS = ( convert_celcius, 'C', 'Celcius' )
88 94  
89 95  
90   -def convert_farenheit(temp_read):
  96 +def convert_farenheit(temp_read, scale = 1):
91 97 """Converts raw temperature sensore value to degrees Farenheit"""
92   - return float(temp_read * 9) / float(5 * SENSOR_SCALE) + 32.0
  98 + return float(temp_read * 9) / float(5 * scale) + 32.0
93 99 CONVERT_FARENHEIT = ( convert_farenheit, 'F', 'Farenheit' )
94 100  
95 101  
... ... @@ -98,6 +104,11 @@ def isempty(string):
98 104 return string is None or len(string) == 0
99 105  
100 106  
  107 +def hex_int(string):
  108 + """Use int()'s auto-detection to parse 10-base and 16-base (0x..) numbers"""
  109 + return int(string, 0);
  110 +
  111 +
101 112 def read_rpi_cpu_temp(args):
102 113 """Reads CPU temperature and converts it to desired unit, returns temperature"""
103 114 with open(args.file, 'r') as f:
... ... @@ -111,6 +122,51 @@ def read_rpi_cpu_temp(args):
111 122 return temp, 1
112 123  
113 124  
  125 +def read_i2c_mcp9808_temp(args):
  126 + """Returns temperature from I2C MCP9808 sensor in desired unit"""
  127 +
  128 + try:
  129 + import smbus
  130 + except ImportError:
  131 + try:
  132 + import smbus2 as smbus
  133 + except ImportError:
  134 + logger.critical("Unable to import either smbus or smbus2 library");
  135 + raise ImportError("missing I2C library, please install python-smbus or smbus2");
  136 +
  137 + try:
  138 + bus = smbus.SMBus(args.i2cbus) # Get I2C bus
  139 + except OSError as e:
  140 + logger.critical(e)
  141 + raise IOError("Invalid I2C bus: %d" % args.i2cbus)
  142 +
  143 + try:
  144 + bus.write_i2c_block_data(args.address, I2C_MCP9808_CONFIG_ADDR,
  145 + I2C_MCP9808_CONFIG)
  146 + bus.write_byte_data(args.address, I2C_MCP9808_PRECISION_ADDR,
  147 + I2C_MCP9808_PRECISION)
  148 + sleep(0.5)
  149 +
  150 + # Read temperature (0x05), 2 bytes (MSB, LSB)
  151 + data = bus.read_i2c_block_data(args.address, I2C_MCP9808_TEMP_ADDR, 2)
  152 + logger.debug('Temperature sensor data from MCP9808 %#02x: 0x%02x%02x',
  153 + args.address, data[0], data[1])
  154 +
  155 + # Convert the data to 13-bits
  156 + temp_read = ((data[0] & 0x1F) * 256) + data[1]
  157 + if temp_read > 4095 :
  158 + temp_read -= 8192
  159 +
  160 + temp = args.converter[0](temp_read, 16)
  161 + logger.debug('Temperature sensor value %d is %.2f%s',
  162 + temp_read, temp, args.converter[1])
  163 + return temp, 1
  164 + except IOError as e:
  165 + logger.critical(e)
  166 + raise IOError("Error while communicating with I2C device %#02x" %
  167 + args.address)
  168 +
  169 +
114 170 def get_w1_sensor_device_filename(args, dev_dir=W1_SENSOR_DEV_DIR,
115 171 prefix=W1_SENSOR_DEV_PREFIX, suffix=W1_SENSOR_DEV_SUFFIX):
116 172 """Auto-determine sensor datafile name (unless args.file is set)"""
... ... @@ -138,8 +194,8 @@ def get_w1_sensor_device_filename(args, dev_dir=W1_SENSOR_DEV_DIR,
138 194 return filename
139 195  
140 196  
141   -def read_w1_temp(args):
142   - """Reads sensor data and converts it to desired unit, returns temperature"""
  197 +def read_w1_ds18b20_temp(args):
  198 + """Returns temperature from 1-wire ds18b20 sensor in desired unit"""
143 199 device_file = get_w1_sensor_device_filename(args)
144 200 lines=[ '' ]
145 201 tries = 0
... ... @@ -160,7 +216,7 @@ def read_w1_temp(args):
160 216 errmsg = 'temperature sensor data format is not supported'
161 217 else:
162 218 temp_read = int(lines[1][equals_pos+2:])
163   - temp = args.converter[0](temp_read)
  219 + temp = args.converter[0](temp_read, W1_SENSOR_SCALE)
164 220 logger.debug('Temperature sensor value %d is %.2f%s', temp_read,
165 221 temp, args.converter[1])
166 222 return temp, tries
... ... @@ -174,11 +230,7 @@ def parse_args():
174 230  
175 231 # Setup argument parser, the workhorse gluing it all together
176 232 parser = ArgumentParser(
177   - epilog='(*) by default the script will look for the first device that '
178   - 'matches %s* in %s, if multiple entries are found -s or -f must '
179   - 'be used to specify which sensor to read.' %
180   - (W1_SENSOR_DEV_PREFIX, W1_SENSOR_DEV_DIR),
181   - description='Nagios check plugin for 1-wire temp. sensor on RaspberryPi'
  233 + description='Nagios check plugin for temperature sensors on RaspberryPi'
182 234 )
183 235 parser.add_argument('-V', '--version',action="version",version=PROG_VERSION)
184 236  
... ... @@ -218,6 +270,16 @@ def parse_args():
218 270 help='read built-in Raspberry Pi CPU temperature')
219 271 cmdparser.set_defaults(func=read_rpi_cpu_temp, cmdparser=cmdparser, retries=0)
220 272  
  273 + i2cparser = ArgumentParser(add_help=False)
  274 + i2cparser.add_argument('-a', '--address', type=hex_int,
  275 + help='I2C Address of sensor, use 0x.. for hex (*)')
  276 + i2cparser.add_argument('-b', '--i2cbus', default=1, type=int,
  277 + help='I2C Bus to use (defaults to 1)')
  278 + cmdparser = subparser.add_parser('i2c_mcp9808', parents=[i2cparser],
  279 + help='read I2C connected MCP9808 sensor',
  280 + epilog='(*) default I2C address for an MCP9808 is 0x18')
  281 + cmdparser.set_defaults(func=read_i2c_mcp9808_temp, cmdparser=cmdparser, retries=0, address=0x18)
  282 +
221 283 w1parser = ArgumentParser(add_help=False)
222 284 pgroup = w1parser.add_mutually_exclusive_group(required=False)
223 285 pgroup.add_argument('-s', '--serial',
... ... @@ -228,8 +290,12 @@ def parse_args():
228 290 help='number of times to retry reading sensor data when'
229 291 ' unstable (defaults to %d)' % W1_SENSOR_READ_RETRIES)
230 292 cmdparser = subparser.add_parser('w1_ds18b20', parents=[w1parser],
231   - help='read 1-wire connected DS18b20 sensor')
232   - cmdparser.set_defaults(func=read_w1_temp, cmdparser=cmdparser)
  293 + help='read 1-wire connected DS18b20 sensor',
  294 + epilog='(*) by default the script will look for the first device that '
  295 + 'matches %s* in %s, if multiple entries are found -s or -f must '
  296 + 'be used to specify which sensor to read.' %
  297 + (W1_SENSOR_DEV_PREFIX, W1_SENSOR_DEV_DIR))
  298 + cmdparser.set_defaults(func=read_w1_ds18b20_temp, cmdparser=cmdparser)
233 299  
234 300 # parse arguments and post-process command line options
235 301 args = parser.parse_args()
... ... @@ -268,7 +334,7 @@ if __name__ == '__main__':
268 334 except (KeyboardInterrupt) as e:
269 335 nagios_exit(NAGIOS_UNKNOWN,'temperature sensor read aborted by user')
270 336  
271   - except (IOError, ValueError) as e:
  337 + except (IOError, ValueError, ImportError) as e:
272 338 nagios_exit(NAGIOS_UNKNOWN,'temperature sensor read failed: %s' % e)
273 339  
274 340 elapse = endtime-starttime
... ...