Merge pull request #1 from myDevicesIoT/feature/systeminfo-python

Replace the system info C library with Python code.

Author: jburhenn

README.rst

@@ -161,10 +161,10 @@ Loading/Unloading Bus Kernel Modules
 
 System info
 -----------
-Information about the device, including CPU, RAM, etc., is currently retrieved via several modules including a C library compiled for the Raspberry Pi, though that will be changed to a Python only implementation in the future. To support a different board you may need to update the agent code for the following items, if applicable:
+Information about the device, including CPU, RAM, etc., is currently retrieved via a few different modules. To support a different board you may need to update the agent code for the following items, if applicable:
 
 General System Info
-  General system info, including CPU, RAM, memory, etc. is retrieved via ``myDevices.os.systeminfo.py`` This is mostly implemented via a C library for the Raspberry Pi, though that will be changed to a Python only implementation in the future. If the C library doesn't work on your device you can disable the C library call until the Python implementation is available at which point you can modify it to support your board.
+  General system info, including CPU, RAM, memory, etc. is retrieved via ``myDevices.os.systeminfo.py`` and ``myDevices.os.cpu.py``. These are mostly implemented using cross platform libraries so they may already provide support for your board. If not, they should be modified or overridden to provide the appropriate system info. If your board does not support all the data values currently implemented you can just provide default values where necessary, though this may affect the data display in the Cayenne dashboard.
 
 Hardware Info
   Hardware info, including make, model, etc. is retrieved via ``myDevices.os.hardware.py``. This should be modified or overridden to provide the appropriate hardware info for your board.

libs/libSystemInformation.so

@@ -1,118 +1,69 @@
-#!/usr/bin/python 
-# -*- coding: utf-8 -*-
-
-'''
-Created on 04.12.2014
-
-@author: plagtag
-'''
+import psutil
+import os
+from glob import glob
 from time import sleep
+from myDevices.utils.logger import exception
 
+class CpuInfo(object):
+    """Class for retrieving CPU info"""
 
-class GetCpuLoad(object):
-    '''
-    classdocs
-    '''
-
-
-    def __init__(self, percentage=True, sleeptime = 1):
-        '''
-        @parent class: GetCpuLoad
-        @date: 04.12.2014
-        @author: plagtag
-        @info: 
-        @param:
-        @return: CPU load in percentage
-        '''
-        self.percentage = percentage
-        self.cpustat = '/proc/stat'
-        self.sep = ' '
-        self.sleeptime = sleeptime
-
-    def getcputime(self):
-        '''
-        http://stackoverflow.com/questions/23367857/accurate-calculation-of-cpu-usage-given-in-percentage-in-linux
-        read in cpu information from file
-        The meanings of the columns are as follows, from left to right:
-            0cpuid: number of cpu
-            1user: normal processes executing in user mode
-            2nice: niced processes executing in user mode
-            3system: processes executing in kernel mode
-            4idle: twiddling thumbs
-            5iowait: waiting for I/O to complete
-            6irq: servicing interrupts
-            7softirq: servicing softirqs
-
-        #the formulas from htop 
-             user    nice   system  idle      iowait irq   softirq  steal  guest  guest_nice
-        cpu  74608   2520   24433   1117073   6176   4054  0        0      0      0
-
-
-        Idle=idle+iowait
-        NonIdle=user+nice+system+irq+softirq+steal
-        Total=Idle+NonIdle # first line of file for all cpus
-
-        CPU_Percentage=((Total-PrevTotal)-(Idle-PrevIdle))/(Total-PrevTotal)
-        '''
-        cpu_infos = {} #collect here the information
-        with open(self.cpustat,'r') as f_stat:
-            lines = [line.split(self.sep) for content in f_stat.readlines() for line in content.split('\n') if line.startswith('cpu')]
-
-            #compute for every cpu
-            for cpu_line in lines:
-                if '' in cpu_line: cpu_line.remove('')#remove empty elements
-                cpu_line = [cpu_line[0]]+[float(i) for i in cpu_line[1:]]#type casting
-                cpu_id,user,nice,system,idle,iowait,irq,softrig,steal,guest,guest_nice = cpu_line
-
-                Idle=idle+iowait
-                NonIdle=user+nice+system+irq+softrig+steal
-                busy = user + nice + system + irq + softrig
-
-                Total=Idle+NonIdle
-                #update dictionionary
-                cpu_infos.update({cpu_id:{'total':Total,'idle':Idle, 'irq': irq, 'softirq': softrig, 'system': system, 'user': user, 'nice': nice, 'busy': busy,'iowait': iowait }})
-            return cpu_infos
-
-    def getcpuload(self):
-        '''
-        CPU_Percentage=((Total-PrevTotal)-(Idle-PrevIdle))/(Total-PrevTotal)
-        '''
-        start = self.getcputime()
-        #wait a second
-        sleep(self.sleeptime)
-        stop = self.getcputime()
-        cpu_load = {}
-        for cpu in start:
-            Total = stop[cpu]['total']
-            PrevTotal = start[cpu]['total']
-            Idle = stop[cpu]['idle']
-            PrevIdle = start[cpu]['idle']
-            CPU_Percentage=((Total-PrevTotal)-(Idle-PrevIdle))/(Total-PrevTotal)*100
-            CPU_Percentage=float('{0:.1f}'.format(CPU_Percentage))
-            cpu_load.update({cpu: CPU_Percentage})
-            del CPU_Percentage
-            CPU_Percentage = None
-        start = None
-        stop = None
-        return cpu_load
-    def build_info(self):
+    def get_cpu_info(self):
+        """Return CPU temperature, load average and usage info as a dict"""
         info = {}
         info['temperature'] = self.get_cpu_temp()
-        info["loadavg"] = self.get_loadavg()
-        info["usage"] = self.getcputime()['cpu']
+        info["loadavg"] = self.get_load_avg()
+        info["usage"] = self.get_cpu_usage()
         return info
+
+    def get_cpu_usage(self):
+        """Return dict with overall CPU usage"""
+        usage = {}
+        try:
+            fields = ('user', 'system', 'idle', 'nice', 'iowait', 'irq', 'softirq', 'steal')
+            usage = {key: value for key, value in psutil.cpu_times()._asdict().items() if key in fields}
+            usage['total'] = round(sum(usage.values()), 2)
+        except:
+            exception('Error getting CPU usage info')
+        return usage
+
+    def get_cpu_load(self, interval = 1):
+        """Return CPU load
+
+        :param interval: time interval in seconds to wait when calculating CPU usage
+        :returns: dict containing overall CPU load, as a percentage
+        """
+        cpu_load = {}
+        try:
+            cpu_load['cpu'] = psutil.cpu_percent(interval)
+        except:
+            exception('Error getting CPU load info')
+        return cpu_load
+
     def get_cpu_temp(self):
+        """Get CPU temperature"""
         info = {}
-        file = "/sys/class/thermal/thermal_zone0/temp"
+        thermal_dirs = glob('/sys/class/thermal/thermal_zone*')
+        thermal_dirs.sort()
         temp = 0.0
         try:
-            with open(file, 'r') as f_stat:
-                content = int(f_stat.read().strip())
-                temp = content/1000.0
-        except Exception as e:
-            print('Temp exception:' + str(e))
+            for thermal_dir in thermal_dirs:
+                try:
+                    thermal_type = ''
+                    with open(thermal_dir + '/type', 'r') as type_file:
+                        thermal_type = type_file.read().strip()
+                    if thermal_type != 'gpu_thermal':
+                        with open(thermal_dir + '/temp', 'r') as temp_file:
+                            content = int(temp_file.read().strip())
+                            temp = content / 1000.0
+                            break
+                except:
+                    pass
+        except Exception:
+            exception('Error getting CPU temperature')
         return temp
-    def get_loadavg(self):
+
+    def get_load_avg(self):
+        """Get CPU average load for the last one, five, and 10 minute periods"""
         info = {}
         file = "/proc/loadavg"
         one     = 0
@@ -121,15 +72,13 @@ def get_loadavg(self):
         try:
             with open(file, 'r') as f_stat:
                 content = f_stat.read().strip().split(' ')
-                one = content[0]
-                five = content[1]
-                ten = content[2]
-        except Exception as e:
-            print('Cpu Loadavg exception:' + str(e))
+                one = float(content[0])
+                five = float(content[1])
+                ten = float(content[2])
+        except Exception:
+            exception('Error getting CPU load average')
         info['one']     = one
         info['five']    = five
         info['ten']     = ten
         return info
 
-# gpl = GetCpuLoad()
-# print(gpl.build_info())