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pimatic-shell-execute

pimatic shell execute plugin

This plugin let you define devices that execute shell commands. Additionally, it allows you to execute shell commands in rule actions. So you can define rules of the form:

if ... then execute "some command"

Configuration

You can load the plugin by editing your config.json to include:

{ 
   "plugin": "shell-execute"
}

Commands are executed parallel by default. With the optional boolean attribute sequentialset to trueshell commands are executed sequentially.

{ 
   "plugin": "shell-execute",
   "sequential": true
}

Optionally, it is also possible to define the shell to be used to execute commands. By default, '/bin/sh' is used on UNIX, and 'cmd.exe' on Windows. It is also possible to set the current working directory (cwd). By default, the current working directory of pimatic is used.

{ 
   "plugin": "shell-execute",
   "shell": "/bin/bash",
   "cwd": "/home/pi/scripts"
}

ShellSwitch Device

Devices can be defined by adding them to the devices section in the config file. Set the class attribute to ShellSwitch. For example:

{ 
  "id": "light",
  "name": "Lamp",
  "class": "ShellSwitch", 
  "onCommand": "echo on > /home/pi/switchState",
  "offCommand": "echo off > /home/pi/switchState",
  "getStateCommand": "echo /home/pi/switchState",
  "interval": 10000,
  "forceExecution": false
}

If the getStateCommand option is set and the interval option is set to a value greater than 0, the getStateCommand is executed in this ms interval to update the state of the switch.

ShellSensor Device

You can define a sensor device with an attribute which gets updated with the output of shell command:

{ 
  "id": "temperature",
  "name": "Room Temperature",
  "class": "ShellSensor", 
  "attributeName": "temperature",
  "attributeType": "number",
  "attributeUnit": "°C",
  "attributeAcronym": "Room",
  "command": "echo 42.0"
}

If you're running pimatic on a RaspberryPi, you can use the following sensors for a quick overview of your system health:

{
  "id": "wlan-strength",
  "name": "WLAN Strength",
  "class": "ShellSensor",
  "attributeName": "wlan-strength",
  "attributeType": "number",
  "attributeUnit": "%",
  "command": "iwconfig wlan0 | grep Signal | sed -n -e 's/^.*Signal level.\\([0-9]*\\).*/\\1/gp'",
  "interval": 15000
},
{
  "id": "mem-usage",
  "name": "Memory Usage",
  "class": "ShellSensor",
  "attributeName": "mem-usage",
  "attributeType": "number",
  "attributeUnit": "MB",
  "command": "free -m | awk '$5 ~ /[0-9.]+/ { print $3 }'",
  "interval": 60000
},
{
  "id": "disk-usage",
  "name": "Disk Usage",
  "class": "ShellSensor",
  "attributeName": "disk-usage",
  "attributeType": "number",
  "attributeUnit": "%",
  "command": "df | awk '/^\\/dev\\/root/ { printf \"%.1f\", ($3/$2)*100 }'",
  "interval": 300000
},
{
  "id": "cpu-temp",
  "name": "CPU Temperature",
  "class": "ShellSensor",
  "attributeName": "cpu-temp",
  "attributeType": "number",
  "attributeUnit": "°C",
  "command": "/opt/vc/bin/vcgencmd measure_temp | cut -d \"=\" -f2 | cut -d \"'\" -f1",
  "interval": 60000
}

ShellPresenceSensor Device

You can define a presence sensor whose state gets updated with the output of shell command. In some use cases the shell command may only detect an external device triggered a "present" event, but cannot detect its absence. In such cases, when theShellPresenceSensor is "present" it needs to be automatically reset to "absent" after some time. For this you can set to autoReset property to true:

{
  "id": "presence",
  "name": "NGINX Server",
  "class": "ShellPresenceSensor",
  "command": "pgrep nginx >/dev/null && echo 1 || echo 0",
  "autoReset": false,
  "resetTime": 10000
}

For device configuration options see the device-config-schema file.