pixelstatus

[WORK IN PROGRESS]

Build color-coded status screens with LED pixels, Raspberry Pi and fadecandy.
Configure section colors using expectations on a HTTP response.
Provides a daemon with task runner, REST API and Web UI.

Demo

OpenGL Simulator:

git clone https://github.com/eins78/pixelstatus
cd pixelstatus
npm install
npm run demo

Configuration

Overview

• SECTION a section of continuos PIXELS on a strip
  has one:

  • TASK something to do (HTTP request, shell command)
    has one:
    • COMPARISON rule(s) to compare against result of a TASK (expect)
      has one:
      • REACTION a state to set on the SECTION

• STATE what to with the PIXELS of a SECTION (set them to a color)

JSON object

See the "Full" (JSON, YAML) and "Minimal" (JSON, YAML) example configuration files and consult this description should questions arise. The "Full" example has two sections, the first is the most minimal, the other is the most verbose config for a section.

• colors: Object. Keys are names of colors to be used in rest of config, values are valid CSS color strings (names, hex, hsl, …).

• sections: Array of Objects with keys:

  • id: unique short name of section (word-characters allowed)
  • description: optional description of the section
  • start: the first pixel which belongs to the section, it will go to the end or one pixel before the next section
  • a key for one of the runners, like:
    • command: run a shell command
    • request: make a HTTP request
  • expect: hash of expectations on (at least one of) the following values (see below for possible expectations):
    • status: exit status of command, or http status of request
    • output: stdout of command, or res of request
    • error: stderr of command, or err of request

• ok: if assert was true, set section to this color

• fail: if assert was false, set section to this color

Tasks

request

Make a HTTP request powered by the request module.

See API there, short synopsis below.

1. Setting it to an URL string makes a GET request to this URL.

   {
     "request": "http://example.com"
   }

2. Setting it to an hash enables all the bells and whistles:

   {
     "request": {
       "method": "GET",
       "url": "https://example.com",
       "qs": { "query": "foobar" },
       "auth": {
         "user": "username",
         "pass": "password",
         "sendImmediately": false
       },
       "headers": {
         "User-Agent": "pixelstatus"
       }
     }
   }

Comparisons

The is only one option at the moment:

expect

Can be in one of the following forms

• simple value (number, string): must be exactly equal to compared value
• hash of "comparators" from the ruler module and the value to compare.

CLI

./draft.coffee examples/config.json -vv

config

First argument must be the path to a config file. It can be a JSON-file as described above, or (structurally equivalent) YAML.

loglevel

Set console log level by appending one or more -v's. -v is 'info', -vv is 'verbose', -vvv is 'debug'.

Credits

The whole project uses lots of great free/open modules and projects:

• https://github.com/scanlime/fadecandy
• http://openpixelcontrol.org
• https://lodash.com
• also see package.json for all the npm packages that are used

It is written in CoffeScript.