monitor

monitor

Monitor is a small Node.js application that runs an arbitrary number of plugins either at an interval, or at specific times of day. These plugins can perform any function from checking train delays, polling other Node.js services, to controlling other applications through requests.

• Standard Plugins
• Plugin Arguments

Standard Plugins

Adding a plugin is easy. Simply place it in the plugins directory and export a single function as the exports. See existing plugins as examples. The plugin will be called according to its configuration in config.json. Specify either AT with a specific time (or 'start'), EVERY to be called at that many minutes interval.

For example to run delays.js every 15 minutes:

"plugins": [
  { "ENABLED": true, "FILE_NAME": "delays.js", "EVERY": 15 }
]

Any plugin can be supplied with arguments at runtime specified in the configuration by adding the ARGS property as the object to provide at invocation in the plugins item.

For example, a list of scheduled requests to update LED lights:

"plugins": [
  { "ENABLED": true, "FILE_NAME": "visuals-scheduler.js", "EVERY": 1,
    "ARGS": {
      "EVENTS": [
        { "NAME": "Morning", "ON": "07:30", "OFF": "08:00", "COLOR": [128, 128, 128] },
        { "NAME": "Nightlight", "ON": "17:30", "OFF": "00:00", "COLOR": [25, 25, 25] },
      ]
    }
  }
]

module.exports = args => {
  const { EVENTS } = args;

  // ...
};

Plugin Arguments

The table below details the arguments available for each provided plugin.

8hr-forecast.js

Show a forecast of one hour per LED on a Mote or Blinkt strip.

Name	Type	Description
LED	Number	Index of LED on connected Mote/Blinkt strip to use for error state.
DARKSKY_KEY	String	Darksky API key.
LATITUDE	Number	Device latitude.
LONGITUDE	Number	Device longitude.
HOURS_AHEAD	Number	Number of hours ahead to look.
TEMP_COLD	Number	Minimum comfortable temperature.
TEMP_HOT	Number	Maximum comfortable temperature.

conduit.js

Send a Conduit packet on a schedule.

For this plugin, the entire ARGS object is the packet to be sent.

delays.js

Show state of select National Rail lines on connected LEDs.

Name	Type	Description
LED	Number	Index of LED to use.

devices.js

Disused.

enviro-datalogger.js

Datalog sensor values from Enviro HAT to file.

This plugin has no ARGS required.

fan-control.js

Control connected 40mm fan based on CPU reported temperature.

Name	Type	Description
GPIO_PIN	Number	GPIO pin on which fan control is connected (FET base, for example).
THRESHOLD	Number	Minimum temperature to turn on the fan.

mdstat.js

Monitor status of one connected RAID disk array with /proc/mdstat.

This plugin has no ARGS required.

post.js

Send a HTTP POST request on a schedule.

Name	Type	Description
URL	String	URL to send POST request to.
JSON	Object	POST payload data.

services.js

Monitor state of local or remote node-microservices apps.

Name	Type	Description
HOST	String	Host where apps are running.
LED	Number	Index of LED to use for status display.

visuals-scheduler.js

Schedule Visuals lights on and off.

Name	Type	Description
EVENTS	Array	List of events.

Each event has the following structure:

Name	Type	Description
NAME	String	Name of the event, like 'wakeup glow'.
ON	String	HH:MM on time.
OFF	String	HH:MM off time.
COLOR	Array	RGB numbers for the color to display.

weather.js

Show general weather conditions on a single LED, prioritising harsh conditions.

Name	Type	Description
LED	Number	Index of LED to show status on.
DARKSKY_KEY	String	Darksky API key.
LATITUDE	Number	Device latitude.
LONGITUDE	Number	Device longitude.
TEMP_COLD	Number	Minimum comfortable temperature.
TEMP_HOT	Number	Maximum comfortable temperature.

web-datalogger.js

Scrape and log value of a portion of a web page on a schedule.

Name	Type	Description
URL	String	URL to read.
BEFORES	Array	Array of string portions to help locate start point.
AFTER	String	String after end point.
ATTIC_KEY	String	Key if required to store values in Attic app instance.