Package Summary

scriptable_monitoring

Maintainer: Igor Makhtes <igor AT cogniteam DOT com>
Author: Igor Makhtes <igor AT cogniteam DOT com>
License: MIT
Source: git https://github.com/cogniteam/scriptable_monitoring.git (branch: master)

Contents

Example script
1. Predicate
2. Python
Documentation
1. Scripts
  1. Configuration parameters

The node manages script addition, removal and execution. It also provides an information retrieval interface for available scripts and some useful details about each script.

Example script

Suppose we have a node that publishes current CPU usage to the /cpu topic. Each message contains an array named cores with usage information for each core. We also have a topic with configuration information: /config.

Now we will create a simple script which will warn about high cpu usage.

Predicate

   1 #! type predicate
   2 #! name cpu_monitor
   3 #! interval 1
   4 #! hardware_id lab_pc_1
   5 #! fail warn
   6 core1 = {/cpu/cores[0:1]}
   7 core2 = {/cpu/cores[1:2]}
   8 core3 = {/cpu/cores[2:3]}
   9 core4 = {/cpu/cores[3:4]}
  10 cpu_th = {/config/cpu_threshold}
  11 core_th = {/config/core_threshold}
  12 average = (core1 + core2 + core3 + core4) / 4.0
  13 average < cpu_th
  14 core1 < core_th
  15 core2 < core_th
  16 core3 < core_th
  17 core4 < core_th

Python

   1 #! name cpu_monitor
   2 #! interval 1
   3 #! hardware_id lab_pc_1
   4 #! fail warn
   5 core1 = topic("/cpu/cores[0:1]")
   6 core2 = topic("/cpu/cores[1:2]")
   7 core3 = topic("/cpu/cores[2:3]")
   8 core4 = topic("/cpu/cores[3:4]")
   9 cpu_th = topic("/config/cpu_threshold")
  10 core_th = topic("/config/core_threshold")
  11 average = (core1 + core2 + core3 + core4) / 4.0
  12 validate.is_true(average < cpu_th, "Cpu usage too high")
  13 validate.is_true(core1 < core_th, "core1 usage too high")
  14 validate.is_true(core2 < core_th, "core2 usage too high")
  15 validate.is_true(core3 < core_th, "core3 usage too high")
  16 validate.is_true(core4 < core_th, "core4 usage too high")

You can activate the script using rqt plugin - http://wiki.ros.org/scriptable_monitor_rqt

Adding new script

Documentation

Scripts

Configuration parameters

Parameters are preceded by '#!'. Syntax:

 #! parameter_name parameter_value

There is one required parameter: "name" - the identification name of the script, it must be unique.

Example:

 #! name cpu_monitor